Emma Lethbridge Horsemanship

The Different Techniques Known as Clicker Training

January 30, 2014February 1, 2014 Skynetlikesponies

When considering a way to train their horse using positive reinforcement, most horse owners find themselves investigating clicker training. However, once the horse owner starts to read into clicker training, or visits a few clinics, it soon becomes apparent that different trainers use clicker training in different ways. Clicker training is not one singular technique, but a tool, applied in different ways by different trainers. The benefits and potential difficulties associated with each of these approaches to clicker training will be discussed in this article, with the aim that this will hopefully this will abate some of the confusion that can be experienced by owners new to clicker training.

Before we begin, I will quickly review the basics of clicker training theory as applied to practical horse training. Very simply clicker training is a form of positive reinforcement training. Positive reinforcement being the addition of something pleasurable to the horses environment in consequence to the horse performing a desirable behaviour. Positive reinforcement encourages the desired behaviour to reoccur in the future. Anything that the horse finds pleasurable, for example food rewards or stroking, can be used for the purposes of positive reinforcement training, although food rewards are most commonly used. During positive reinforcement the reward must be delivered immediately as the desired behaviour is performed by the horse, so that only the desired behaviour is reinforced.

The definition of positive reinforcement – An increase in the future frequency of a behaviour due to the addition of a pleasurable stimulus immediately following said behaviour.

Positive reinforcement alone is a very effective training method, however, it relies on the immediate delivery of the reward as the horse performs the desired behaviour. Clicker training makes reinforcement of behaviour at the correct moment easier, because, rather than having to deliver the reward to the horse’s mouth at the moment they perform the desire behaviour, the click noise can mark the desire behaviour and the reward can be delivered as soon as possible. The association of the click noise with food reward, transforms the click noise into a secondary reinforcer, which simply means that the click has taken on reinforcing properties and thus become rewarding. Once an association between the click and food reward has been establish, and the click has become a secondary reinforcer, the click can then be used to communicate to the horse when they have performed a desired behaviour. Marking the behaviour using the audible ‘click’ of the clicker is beneficial to any training where the trainer can’t deliver reward immediately following a correct behavioural response, e.g. when the horse is at distance or being ridden. The click of the clicker is a good sound for marking correct behavioural responses because it is short and crisp. Some trainers prefer to use a ‘cluck’ sound made by the tongue for the same purpose. Currently, there is no scientific evidence to suggest that the use of a tongue ‘cluck’ is less or more effective than the use of a clicker.

The definition of a secondary reinforcer – A secondary reinforcer, also known as a conditioned reinforcer, is a stimulus (such as a click) that when consistently paired with a pleasurable stimulus (such as food) functions as a reinforcer.

The use of the click sound within clicker training has been applied in different ways by different horse trainers. The key factor, which will be discussed in this article, is how different trainers apply the clicker practically during training. To address this topic, we will consider the use of the click as a terminal bridge and as an intermediate bridge. Now the key to understanding the use of clicker in training is to understand, but not get bogged down in, the terminology. I will explain the theory, but also how the theory is practically applied in everyday horse training. The first thing that needs to be explained is that the click of the clicker is know as a bridging stimulus, this is because it bridges the gap between the desired behaviour and the arrival of the food reward. The click says to the horse ‘yes that’s the behaviour I want and your reward is coming’. However, the click can be one of two types of bridge. It can be a terminal bridge that says ‘yes, well done, finished’, or an intermediate bridge which says to the horse ‘yes, keep going your on the right track’. In practise this mean that the click sound either signals to the horse that they were performing the desired behaviour and they can stop for reward (a terminal bridge), or in the case of the intermediate bridge, the click signals to the horse that they are doing the correct behaviour and to continue until the terminal bridge, which will be a different signal.

It is most common in training to use the click sound of the clicker as a terminal bridge. In practical terms this means that the click is used to signal to the horse to stop and receive their reward. For example, if you were teaching a horse to touch a target with there muzzle, you would click the horse once they touch the target and then reinforce the behaviour with the food reward. If you wanted the targeting behaviour to last longer you would shape the behaviour by gradually leaving longer periods of time between the start of the targeting behaviour and the click. This method of clicker training is used by Alexander Kurland (2001) and Becky Holden, amongst others. There are both pros and cons to this method.

The pros of the terminal bridge clicker training method –

◦This method can be used to teach everything, from basic ground work to advanced riding exercises.

◦The horse can be easily rewarded for desired behaviour, even at a distance or whilst ridden.

◦Owners can usually pick up this method easily under instruction.

The cons of the terminal bridge clicker training method –

◦The method doesn’t include a intermediate bridge stimulus so the horse can be told to stop to be rewarded but not to keep performing the same behaviour, instead the behaviour is modified using shaping or chaining.

Now to discuss the use of the clicker as an intermediate bridge stimulus. When the click sound is used as an intermediate bridge the click says to the horse – ‘Yes, keep going you’re on the right track’. Using the targeting example given earlier, to teach a horse to touch a target using the click as an intermediate bridge, the trainer would click the horse for touching the target to encourage the horse to continue touching the target, until the terminal stimulus was given. The click, which can occur a variable amount of times before the terminal stimulus is given, encourages the horse to continue the behaviour they are currently performing. Ben Hart (2008) is the most famous trainer that uses the clicker as an intermediate bridge stimulus. Ben trains using the hand going to the reward holder as the terminal stimulus. There are also pros and cons to the intermediate bridge method of clicker training.

The pros of the intermediate bridge clicker training method –

◦This method can be used to teach all ground work activities.

◦The horse can be easily rewarded for desired behaviour, even at a distance.

◦The horse can be given guidance as to whether or not the behaviour they are performing is desirable, and be given confidence to continue the behaviour, without stopping for reward.

The cons of the intermediate bridge clicker training method –

◦Some owners find applying the clicker as an intermediate bridge stimulus more difficult, although I suspect this is because most of the literature available describes the terminal bridge method.

◦The terminal bridge stimulus of this method of clicker training often isn’t audible, and thus this method is a little more difficult to apply if the horse can’t directly see the hander, e.g. during ridden work.

Both these methods of clicker training are effective modes of communication with the horse, as such both methods have been applied with great success to training horses for many jobs. Interestingly, neither method has been scientifically shown to be more effective than the other, therefore the deciding factor when choosing how to apply clicker training with your own horses must be which method best suits your horse, your ability and your training. I highly recommend reading literature from many different clicker trainers, and ideally, also seeing the methods demonstrated, before you decide which method will be best for you and your horse.

References

Alexandra Kurland (2001). Clicker Training For Your Horse. Ring Books.

Ben Hart (2008). The Art and Science of Clicker Training for Horses: A Positive Approach to Training Equines and Understanding Them. Souvenir Press Ltd.

Positively Encouraging Behaviour

January 30, 2014 Skynetlikesponies

For those embarking on training their horses and wishing to use mostly or completely training which is based in positive reinforcement, the problem of how to encourage the behaviours they want to train to occur, so that they may be rewarded and propagated, is often encoutered. In conventional training desired behaviours are often encouraged through the use of pressure and there is the misconception that only free-shaping is available to those who practise positive reinforcement training. In free-shaping the trainer waits for the horse to perform the desired behaviour and then rewards its presentation. However, there are methods which can be used to encourage behaviour without the use of pressure or, indeed, waiting for the behaviour to occur of its own volition.

Targeting is the most popular positive method of encouraging wanted behaviour in the horse. For the purpose of targeting the horse is taught, using clicker training or another positive reinforcement method, to go to or follow a target object on command. This can be a static marker or a movable object. Once trained, the horse can easily learn to perform new and/or wanted behaviours by following the target. Full guides on how to teach targeting can be found in most clicker training books and my own book (http://www.amazon.co.uk/Knowing-Your-Horse-Learning-Behaviour/dp/1405191643/ref=sr_1_1?ie=UTF8&qid=1339968870&sr=8-1).

Teaching your horse to target can be invaluable for training both basic and complex behaviours; really the only limitation to training is the imagination of the trainer. Once the wanted behaviour is reliably occurring in response to the target, it can be put on an appropriate cue and the target is gradually removed over a short period of time. A common misconception in clicker training is that the target remains as part of the trained behaviour forever; however, this does not represent the goal of target training.

Some common applications of targeting training in horse training include:

Leading, head-lowering, staying in a desired location, basic safety behaviours (e.g. backing and coming on cue), head collar/bridling routines, mounting/dismounting, spook busting, teaching lungeing, and loading into trailers or horse boxes.

Target training has also been studied scientifically, and been observed to be an effective method of horse training. The links below describe research which investigated training horses to load using targeting.

Click to access Hendriksen%202011%20postive%20negative%20reinforcement.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1284337/

http://www.ncbi.nlm.nih.gov/pubmed/21310219

The second most popular method of positively encouraging the horse to present a wanted behaviour is ‘lure and reward’. The term ‘lure’ can often put people off due to negative associations with the word; a better name for this technique is possibly ‘guide and reward’. At its core the method is very similar to the previously describe target training, the horse follows a food guide, thereby performing a desired behaviour and receiving reward. Most

trainers reward from a treat held in the other hand. Obviously doing this training with horses who have not yet learnt not to mug is unwise. However, other than this caveat, the training can be very effective and enjoyable for both horse and trainer. Again, once the horse is reliably performing the behaviour with the target a cue is given and the guide gradually removed. The guide should not be the cue. This process should not take longer than a few sessions, especially for a basic behaviour. Interestingly, this is one of the most commonly used training methods employed by respected dog trainers. Again comprehensive instructions on how to successful use this method with your horse can be found on the internet or in appropriate books.

Finally, using a cue to mean ‘well done, keep going’ as well as a separate ‘good, finish’ cue, can be useful for encouraging the expression of new desired behaviours. How you apply this in training will depend on the individual preferences of the trainer and the previously employed method of positive training. Personally, I like to use to different sounding clicks, which I make with my mouth rather than a clicker, but this is not the only possible method of application. One click sound means ‘continue as you are’, the other communicates ‘finish’. This allows me a more elegant flow of communication to the horse, as well as an active means of encouraging the horse to perform a wanted behaviour in a positive manner. Once the horse has performed the desired behaviour, they may be given the finish signal to indicate they did well and to rest and wait for reward (particular useful if the horse is at a distance from the handler).

If you would like more information on these training techniques briefly discussed here, please feel free to comment or message me at my email address

Can Horses Learn Over Night?

January 30, 2014 Skynetlikesponies

Over the years many horse owners have said to me ‘why does my horse seem to learn things over night and perform better the next day?’ Well that’s because your horse really does learn over night through a process called latent learning. Latent learning is really interesting! It is a psychological phenomena whereby information is better recalled 12 – 24 hours later than at the time of learning without further reinforcement. So if your horse, or indeed you, learn a new piece of information, over night your brain will consolidated the short term memories into long term ones and you will better be able to recall this information. Memory consolidation is also thought to be a key function of sleep, sleep thus aids learning, which is why it is not a good idea to stay up the night before an exam cramming information. The recall of this information will not be as good as if it had been learnt a night or so before. With regards to latent learning mammal brains behave in very similar ways, so you and your horse will have this learning process in common.

The science bit. Neurologically latent learning is thought to occur because neurons in the brain require time in order to create connections, or strengthen present ones, which encode the new information. The creation of connections in the brain is how we learn new information. For information to be transferred to long term memory from the short term memory engaged at the time of learning, something called Long Term Potentiation (LTP) needs to occur within Hebbian learning. Bare with me! Hebbian learning can be simply defined as the formation of new neural connections in response to new information to encode memory. These new connections require LTP to form a strong connections between neurons at the cellular level. LTP is how the neuron cells in the brain stregthen their connections.

The brain comunicates messages from cell to cell through the use of chemical messengers known as neurotransmitters. LTP is the formation of new neurotransmitter receptors which responds to the neurotransmitters release by connecting cells. The more receptors there are at the connection the stronger the response of the neuron cell will be. Stronger connections mean more effective consolidation of memories from short term to long term memory and thus better learning. For the protein necessary for LTP to be synthesised takes up to 24 hours and is aided by sleep. After 24 hours your horse will have a consolidated long term memory of their training.

(Interestingly, it is also theorised that the forgetting of information is caused by the weakening of neuron connections, known as long term depression.)

At the level of training this means that after you have achieved a reasonably high correct response rate in your horse, even if this has taken only a short amount of time, there is no point in continuing to drill the horse as LTP will still require time to convert the information into long term memories. Letting the horse ‘sleep on it’ is really the best thing you can do, because until the horse has had time to form the new neural connections and possibly strengthen old ones the horse can not perform at a higher level, even if the trainer drills them. In fact, if the trainer continues to drill the horse the horse may become bored or tired which would have the opposite of the desired effect. Not only will the horse be unable to produce a better response but, in addition, the horse may become bored or tired and thus have negative memories of the training. However, if the horse is allow to rest after the trainer has acheived a desirable correct response rate, the horse will be better able to perform the trained behaviour after this time as the new information will be encoded through enhanced connections in brain. Allowing time for latent learning to occur will mean that the horse will be more able to provide the correct response reliably during subsequent training sessions.

For example – You are training a new behaviour, say training your horse to perform a basic turn-on-the-forehand. After 15-20 min your horse is producing turn on the forehand steps on cue 8 or 9 times out of ten. Rather than continuing to drill the horse in turn on the forehand for an hour and maybe getting a 9 out of 10 correct response ratio, not to mention a very fed up horse, it would be best to reward the horse greatly for their correct response and end the session or move on to a different activity. The next day the horse will have consolidated the turn-on-the-forehand cue to long term memory and will be better able to respond correctly and the trainer able to continue refining the movement with out drilling the poor horse. This is the brilliance of the latent learning phenomena!

If you have any questions on anything included in this article feel free to leave a comment and I will get back to you.

Thanks you for reading.

Equine Science News 3

January 30, 2014January 30, 2014 Skynetlikesponies

Welcome to my round up of some of the latest releases in equine science. These scientific equine papers have provided some interesting information sure to spark debate and inform our equine management and training practises; including a most important paper which provides evidence that horses ridden in hyperflexion may experience difficulty breathing because of airway obstruction.

Factors in Horse Training

Does learning performance in horses relate to fearfulness, baseline stress hormone, and social rank?

By Janne Winther, Line Christensen Peerstrup Ahrendt, Randi Lintrup, Charlotte Gaillard, Rupert Palme, Jens Malmkvist

“The ability of horses to learn and remember new tasks is fundamentally important for their use by humans. Fearfulness may, however, interfere with learning, because stimuli in the environment can overshadow signals from the rider or handler. In addition, prolonged high levels of stress hormones can affect neurons within the hippocampus; a brain region central to learning and memory. In a series of experiments, we aimed to investigate the link between performance in two learning tests, the baseline level of stress hormones, measured as faecal cortisol metabolites (FCM), fearfulness, and social rank. Twenty-five geldings (2 or 3 years old) pastured in one group were included in the study. The learning tests were performed by professional trainers and included a number of predefined stages during which the horses were gradually trained to perform exercises, using either negative (NR) or positive reinforcement (PR). Each of the learning tests lasted 3 days; 7min/horse/day. The NR test was repeated in a novel environment. Performance, measured as final stage in the training programme, and heart rate (HR) were recorded. Faeces were collected on four separate days where the horses had been undisturbed at pasture for 48h. Social rank was determined through observations of social interactions during feeding. The fear test was a novel object test during which behaviour and HR were recorded.

Performance in the NR and PR learning tests did not correlate. In the NR test, there was a significant, negative correlation between performance and HR in the novel environment (rS=−0.66, P<0.001, i.e. nervous horses had reduced performance), whereas there was no such correlation in the home environment (both NR and PR). Behavioural reactions in the fear test correlated significantly with performance in the NR test in the novel environment (e.g. object alertness and final stage: rS=−0.43, P=0.04), suggesting that performance under unfamiliar, stressful conditions may be predicted by behavioural responses in a fear test. There was a negative correlation between social rank and baseline stress hormones (rS=−0.43, P=0.04), i.e. high rank corresponded to low FCM concentrations, whereas neither rank nor FCM correlated with fearfulness or learning performance. We conclude that performance under stressful conditions is affected by activation of the sympathetic nervous system during training and related to behavioural responses in a standardised fear test. Learning performance in the home environment, however, appears unrelated to fearfulness, social rank and baseline FCM levels.”

http://www.journals.elsevierhealth.com/periodicals/applan/article/S0168-1591(12)00168-2/abstract

Equine Welfare

Effect of head and neck position on intrathoracic pressure and arterial blood gas values in Dutch Warmblood riding horses during moderate exercise.

By Sleutjens J, Smiet E, van Weeren R, van der Kolk J, Back W, Wijnberg ID.

“OBJECTIVE:To evaluate the effect of various head and neck positions on intrathoracic pressure and arterial oxygenation during exercise in horses.

ANIMALS:7 healthy Dutch Warmblood riding horses.

PROCEDURES:The horses were evaluated with the head and neck in the following predefined positions: position 1, free and unrestrained; position 2, neck raised with the bridge of the nose aligned vertically; position 4, neck lowered and extremely flexed with the nose pointing toward the pectoral muscles; position 5, neck raised and extended with the bridge of the nose in front of a vertical line perpendicular to the ground surface; and position 7, neck lowered and flexed with the nose pointing towards the carpus. The standard exercise protocol consisted of trotting for 10 minutes, cantering for 4 minutes, trotting again for 5 minutes, and walking for 5 minutes. An esophageal balloon catheter was used to indirectly measure intrathoracic pressure. Arterial blood samples were obtained for measurement of Pao(2), Paco(2), and arterial oxygen saturation.

RESULTS:Compared with when horses were in the unrestrained position, inspiratory intrathoracic pressure became more negative during the first trot (all positions), canter and second trot (position 4), and walk (positions 4 and 5). Compared with when horses were in position 1, intrathoracic pressure difference increased in positions 4, 2, 7, and 5; Pao(2) increased in position 5; and arterial oxygen saturation increased in positions 4 and 7.

CONCLUSIONS AND CLINICAL RELEVANCE:Position 4 was particularly influential on intrathoracic pressure during exercise in horses. The effects detected may have been caused by a dynamic upper airway obstruction and may be more profound in horses with upper airway disease.”

http://www.ncbi.nlm.nih.gov/pubmed/22452499

More information on the above paper can be found at http://www.thehorse.com/ViewArticle.aspx?ID=20201

On the significance of adult play: what does social play tell us about adult horse welfare?

By Martine Hausberger, Carole Fureix, Marie Bourjade, Sabine Wessel-Robert and Marie-Annick Richard-Yris

“Play remains a mystery and adult play even more so. More typical of young stages in healthy individuals, it occurs rarely at adult stages but then more often in captive/domestic animals, which can imply spatial, social and/or feeding deprivations or restrictions that are challenging to welfare, than in animals living in natural conditions. Here, we tested the hypothesis that adult play may reflect altered welfare states and chronic stress in horses, in which, as in several species, play rarely occurs at adult stages in natural conditions. We observed the behaviour (in particular, social play) of riding school horses during occasional outings in a paddock and measured several stress indicators when these horses were in their individual home boxes. Our results revealed that (1) the number of horses and rates of adult play appeared very high compared to field report data and (2) most stress indicators measured differed between ‘players’ and ‘non-players’, revealing that most ‘playful’ animals were suffering from more chronic stress than ‘non-playful’ horses. Frequency of play behaviour correlated with a score of chronic stress. This first discovery of a relationship between adult play and altered welfare opens new lines of research that certainly deserves comparative studies in a variety of species.”

http://www.springerlink.com/content/a773802p37590541/

Training the Ridden Horse

Horse walker use in dressage horses

By T.J. Walker, S.N. Collins and R.C. Murray

“Horse walkers have become popular in the modern exercise regime for dressage horses, however recent investigations of injury risk factors have indicated a significant association between horse walker use and lameness. A detailed telephone questionnaire was conducted to document horse walker usage and assess whether horse walker use could predispose dressage horses to lameness. Information on horse walker features and use, and individual horse lameness history was recorded. Chi-squared tests were performed to identify horse walker variables associated with lameness. Although analyses failed to establish a direct link between lameness and any specific horse walker feature, the high proportion of lame horses in this study suggests that there is an underlying and, as yet, unidentified cause of lameness related to horse walker usage.”

http://wageningenacademic.metapress.com/content/j3q3511435340324/

The effect of double bridles and jaw-clamping crank nosebands on temperature of eyes and facial skin of horses

By Paul McGreevy, Amanda Warren-Smith and Yann Guisard

“Any apparatus that restricts a horse’s movement can compromise welfare. Eye temperature as measured remotely using infrared thermography is emerging as a correlate of salivary cortisol concentrations in horses. This article explores the effect on the temperature of the eyes and facial skin of horses wearing devices that restrict jaw movements. In certain equestrian disciplines, unacceptable equine oral activity, such as gaping of the mouth, is penalized because it reflects poor training and lack of compliance. This explains the wide range of nosebands and flash straps designed to prevent the mouth opening. Some of these nosebands are banned from higher-level dressage competitions in which double bridles are mandatory, possibly because they are regarded as restrictive. Nevertheless, the current international rules overlook the possibility that noseband can appear innocuous even though some designs, such as the so-called crank noseband, can be ratcheted shut to clamp the jaws together. Some equestrian manuals and competition rule books propose that “two-fingers” be used as a spacer to guard against overtightening of nosebands but fail to specify where this gauge should be applied. The vagueness of this directive prompted us to undertake a small random survey of the finger dimensions of adult men (n = 10) and women (n = 10). There were significant sex differences in the measurements of fingers of adults (P < 0.001), thus illustrating that the “two-finger rule” is not a reliable guide for standardized noseband fastening. Infrared thermography was used to measure the temperature of facial skin and eyes of adult horses (n = 5) wearing a double bridle with and without a cavesson noseband.

A taper gauge was developed based on the mean circumference of adult index and middle fingers (9.89 ± 0.21 cm), and this was used as a spacer at the nasal planum or beside the mandible when tightening the noseband. The nosebands were fastened significantly tighter when the taper gauge was used beside the mandible than at the nasal planum (P = 0.02). Wearing double bridles and nosebands that had been tightened with and without the taper gauge caused an increase in eye temperature compared with baseline values (P = 0.012), and the tighter the noseband was fastened, the cooler the facial skin of the horse (and, presumably, the greater the impairment of vascular perfusion) when compared with baseline values (P = 0.016). This study suggests that horses wearing double bridles and tight nosebands undergo a physiological stress response and may have compromised vascular perfusion. Consequently, on welfare grounds, the use of nosebands that cause any constriction of jaw movement should be reviewed as soon as possible.”

http://www.journalvetbehavior.com/article/S1558-7878(11)00143-2/abstract

Pilot study of behavior responses in young riding horses using 2 methods of making transitions from trot to walk

By Agneta Egenvalla, Marie Eisersiöb and Lars Roepstorffc

“According to the principles of negative reinforcement, when an aid has been given to an animal, it should be released as soon as the desired response has been achieved, and, if performed well, may be associated with fewer conflict behaviors than otherwise. In riding, pressure in the horse’s mouth from the bit is used to give signals to the horse, and both rein tension and patterns of releasing this tension will vary. The aim of this pilot study was to study horse behavior during 2 different methodologies used to shape relatively naïve horses to a deceleration signal while making downward transitions from trot to walk. Method 1 involved relief from rein tension at the first attempt to perform a correct response (M1), and method 2 entailed that rein tension was relieved at the completed correct response (M2). Four horses were ridden by 4 riders over 4 days (1 rider each day), and each horse made 10 transitions each day for each method, which produced 320 transitions. Rein tension was recorded, and horse behavior and rider signal behaviors were evaluated from video recordings. Horse behavior was divided into the following 3 different categories: “pushing against the bit,” “moving away from the bit,” and “decelerating.” Linear models were constructed tracking the percent of the transition time that horses demonstrated at least 1 behavior in the “pushing against the bit,” “moving away from the bit,” and “decelerating” categories, and with random effects for rider, horse, and transition number nested within horse. Fixed effects analyzed were the methods, proportion of the transition time above 30 N for each rein, and the rider signal behaviors. M1 and M2 had on average 19% (standard deviation: 16) and 38% (standard deviation: 23) of the time with >30 N per rein, respectively. In the models for the “pushing against the bit” behaviors, M2 increased rein tension and “exerting pressure on the reins” increased the level of these behaviors. “Releasing pressure” interacted with “pulling back on the reins”; this combination was associated with an increased level of “pushing against the bit” behaviors. The “decelerating” behavior was associated with lower rein tension. In the “decelerating” behavior models, “pulling back on the reins” led to decreased “decelerating” behavior, whereas “still hand” and “releasing pressure” led to increased “decelerating” behavior; however, the interaction “pulling back on the reins” and “releasing pressure” led to decreased “decelerating” behavior. “Moving away from the bit” had no significant determinants. We concluded that fewer “pushing against the bit” behaviors were created by M1 and that a lower rein tension was associated with the “decelerating” behavior. Reinforcing the horse’s attempts, to assist in finding the correct response, benefits the welfare of the horse, and importance of a light hand should be continuously emphasized during riding education.”

http://www.sciencedirect.com/science/article/pii/S1558787811001481

Equipment and training risk factors associated with ridden behaviour problems in UK leisure horses

By Jo Hockenhull and Emma Creighton

“Ridden behaviour problems are prevalent in the UK leisure horse population and may have implications for horse welfare and rider safety. This study aimed to identify risk factors associated with ridden behaviour problems in UK leisure horses from the training approaches and equipment used with them. An Internet survey was used to collect data on 1326 horses from a convenience sample of leisure horse owners. The survey asked owners to report the frequency their horses displayed fifteen ridden behaviour problems over the previous week. Data on the frequency of occurrence of behaviour in four components of related ridden behaviour problems were explored for association with details of the horse’s working life, including the type of tack, equipment and training used, and the frequency the professional services of saddlers and farriers were employed using logistic regression analyses. Behaviour data were generated for 791 individual horses. Risk factors associated with the ridden behaviour problems emerged as three themes. One related to the design and fit of the saddle, with dressage and working hunter saddles associated with a reduced risk of ridden behaviour problems compared to general purpose saddles. The horse’s footcare and shoeing regime was associated with three of the four groups of behaviour problems. An extended interval (seven weeks or more) between farrier visits was associated with an increased risk of discomfort behaviour. Taking an outcome-centred approach to training, for example through the use of artificial training aids, was associated with an increased risk of behaviour problems while spending more time with the horse outside of training situations, a more horse-centred approach, was associated with a reduced risk of problems. Further research is required to understand the causal relationships behind these associations, with the aim of improving the welfare of the horse and the well-being and safety of its rider.”

http://www.journals.elsevierhealth.com/periodicals/applan/article/S0168-1591(12)00020-2/abstract

I hope you enjoy this collection of abstracts as much as I did. If you have a question about any of the abstracts or the terminology used, please feel free to leave a comment or email me and I will happily answer your questions.

Equine Science News 2

January 30, 2014 Skynetlikesponies

Here are a collection of briefs (abstracts) from the latest papers published in Equine science. The abstracts below include information which may inform your training, your husbandry or at least provide some interesting commentary on equine-kind and how we as humans interact with them in the domestic environment. Included are a collection of abstracts from the latest scientific papers published this year and so provide the most current insight into the horse and their behaviour. Whether you are a casual rider or a professional horse person this is information that you need to know. I hope you enjoy this collection of abstracts as much as I did. If you have a question about any of the below abstracts, or the terminology used, please feel free to leave a comment and I will happily answer your questions.

Behaviour

Concurrent Lactation and Pregnancy: Pregnant Domestic Horse Mares Do Not Increase Mother-Offspring Conflict during Intensive Lactation

Jitka Bartošová, Martina Komárkova, Jana Dubcová,Luděk Bartoš, Jan Pluháček

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0022068

Lactation is the most energy demanding part of parental care in mammals, so parent-offspring conflict arises over milk provided by the mother. In some species females commonly become pregnant shortly after parturition of previous young. This further intensifies mother-offspring conflict due to concurrent pregnancy and lactation. In equids it has been well established that pregnant females wean their foals earlier than non-pregnant ones. Intensified mother-offspring conflict was presumed to associate with pregnancy also during the period of intensive lactation, i.e., before the weaning process starts. We investigated the effect of pregnancy on suckling behaviour characteristics as indicators of mother-offspring conflict in domestic horses. Contrary to expectation, here we provide evidence of a decreased mother-offspring conflict related to pregnancy in lactating females during first two trimesters of pregnancy. Pregnant mares provided longer suckling bouts and did not reject or terminate suckling of their foals more often than non-pregnant mares. Our results suggest that pregnant mares cope with parallel investment into a nursed foal and a foetus through enhancing nursing behaviour in early stages of pregnancy before the initially low requirements of the foetus increase. They compensate their suckling foal with the perspective of its early weaning due to ongoing pregnancy.

Effects of Repeated Regrouping on Horse Behaviour and Injuries

Janne Winther Christensen, Eva Søndergaard, Karen Thodberg, Ulrich Halekoh

Applied Animal Behaviour Science

Volume 133, Issues 3-4, Pages 199-206, September 2011

Domestic horses are faced with social challenges throughout their lives due to limitations in social contact, space restrictions and frequent changes in social companionship. This is in contrast to natural conditions where horses live in relatively stable harem bands. Currently, little is known about how repeated regrouping affect horse behaviour and welfare, and it is unknown whether horses may adapt to regrouping. In this study, we aimed to investigate the effects of an unstable group structure, caused by weekly regroupings, on behaviour and frequency of injuries in young horses. Forty-five horses were included in the study and were randomly assigned to the treatments; Stable (S; seven groups of three horses) or Unstable (U; eight groups of three horses). The experimental period lasted 7 weeks, during which horses in Stable groups remained in the same group, whereas one horse was exchanged between Unstable groups every week. The groups were kept in 80 m × 80 m grass-covered enclosures and were fed additional roughage on the ground daily. Social interactions were recorded in Unstable groups immediately after each regrouping (30 min), and in both Stable and Unstable groups on day 1, 3 and 6 after each regrouping (2 × 20 min/group/day). Injuries were scored by the end of the experimental period. The level of aggression shown by horses in Unstable groups immediately after regrouping was not affected by week (F5,35 = 0.42, P = 0.83), indicating that horses neither habituated, nor sensitized, to repeated regrouping. Compared to horses in Stable groups, more agonistic behaviour was shown by horses in Unstable groups (i.e. non-contact agonistic; F1,65 = 5.60, P = 0.02), whereas there was no treatment effect on other variables. The level of play behaviour appeared, however, to be more variable in Unstable groups. There was a significant effect of week on the level of contact agonistic interactions as well as greeting behaviour, due to a high occurrence in weeks 4–6. Non-contact agonistic interactions constituted the major part of agonistic interactions (66%). Possibly as consequence, no serious injuries were registered and there was no treatment effect (U = 184; P = 0.11). We conclude that the behaviour of young horses is affected by group management, and that horses appear not to adapt to weekly regroupings.

Competition Horses Housed in Single Stalls (II): Effects of Free Exercise on the Behavior in the Stable, the Behavior during Training, and the Degree of Stress

Hanna Werhahn MS, Engel F. Hessel Prof Dr, Herman F.A. Van den Weghe Prof Dr Ir

Journal of Equine Veterinary Science

July 2011

Although housing horses in single stalls limits their natural behavior to a great extent, this housing system is widespread in Germany, especially for competition horses. To improve the welfare of this system, free exercise on pastures or paddocks is deemed suitable, but it is also feared because of injuries and decreased willingness or motivation to perform. In the present study, three treatments were investigated with regard to their effect on the behavior of six competition horses in the stable, behavior during training, and on their degree of stress: daily training without free exercise (no turnout [NT]), solitary turnout for 2 hours after training, and 2-hour turnout in groups of two after training (group turnout). The horses’ behavior in the stable was continuously analyzed through video recordings (2 pm to 6 am) on 3 days at the end of each treatment. The degree of stress was evaluated daily by heart rate variability at rest. The behavior during training was evaluated by a questionnaire answered by the riders, and the distance covered during training was measured by global positioning system. When NT was allowed, the horses showed less lying in the stable compared with the treatments with turnout. Heart rate variability measurements resulted in great individual differences, but generally, there was a higher degree of stress shown with the treatment NT according to the following parameters: standard deviation of inter-beat-intervals (SDNN), square root of the mean of the sum of the squares of differences between successive inter-beat-intervals (RMSSD), and ratio between low frequency and high frequency (LF/HF). The willingness to perform was evaluated as being slightly better in the treatments with turnout than in the treatment without turnout.

Motivation for Social Contact in Horses Measured by Operant Conditioning

Eva Søndergaard, Margit Bak Jensen, Christine J. Nicol

Applied Animal Behaviour Science

Volume 132, Issues 3-4, Pages 131-137, July 2011

Although horses are social animals they are often housed individually with limited social contact to other horses and this may compromise their welfare. The present study included eight young female horses and investigated the strength of motivation for access to full social contact, head contact and muzzle contact, respectively, to a familiar companion horse. Horses were housed individually next to their companion horse and separations between pens prevented physical contact. During daily test sessions horses were brought to a test area where they could access an arena allowing social contact. Arena access during 3 min was given after completion of a predetermined number of responses on a panel. Fixed ratios (FR) of 8, 16, 24, 32 and 40 responses per arena access were applied in a random order, one per daily test session, within each test week (Monday to Friday), and the number of rewards per daily test session was recorded. All horses could access all three types of social contact in a cross-over design, and an empty arena was used as control. Motivational strength was assessed using elasticity of demand functions, which were estimated based on the number of rewards earned and FR. Elasticities of demand for the three types of social contact were low (−0.20), and not significantly different, although increasing FR still resulted in a decrease in rewards obtained for all three types of social contact (P < 0.001). Across FR-levels horses earned more rewards for social contact than for an empty arena, as shown by much higher intercept values (2.51 vs. 0.99; P < 0.001). However, the elasticity of demand for infrequent access to an empty arena (−0.08) was lower than for social contact (P < 0.01) and not significantly different from zero (P = 0.07). Horses performed more social behaviour the lesser the restriction on social contact (full > head > muzzle). However, the finding that horses showed a similar and high motivation for all three types of social contact suggests that they are valued equally highly in a situation where the alternative is no social contact.

Preference and Demand for Exercise in Stabled Horses

Joyce Lee, Toby Floyd, Hollis Erb, Katherine Houpt

Applied Animal Behaviour Science

Volume 130, Issues 3-4, Pages 91-100, March 2011

Operant conditioning and two choice preference tests were used to assess the motivation of horses to be released from straight and from box stalls. The motivations for food, a companion, and release into a paddock were compared when the horses had to work for each commodity at increasing fixed ratios of responses (panel presses) to reward in an equine operant conditioning stall. The motivation for food (mean ± SEM = 258 ± 143) responses was much greater than that for either release (38 ± 32) from a straight stall into a large paddock alone or into a small paddock with another horse (95 ± 41) (P = 0.04). When given a two choice preference test between exercise on a treadmill for 20 min or returning to their box stalls, eight of nine horses chose to return to their stalls. In a two choice preference test six of eight horses in box stalls chose to be released into a paddock alone. Horses were given a series of two choice preference tests to determine how long they preferred to be in a paddock. After 15 min in the paddock the horses were re-tested, but all chose the paddock when released into a paddock with three other horses. They were retested every 15 min until they chose to return to their stalls. They chose to stay out for 35 ± 6 min when other horses were in the paddock but for only 17 ± 2 min when they would be alone. When deprived of stall release for 48 h the horses chose to remain in the paddock with other horses for 54 ± 6 min, but showed no compensatory behavior when they were alone (duration chosen = 16 ± 4 min). These findings indicate that horses are not strongly motivated to exercise alone and will choose not to endure forced exercise on a treadmill. The social context of voluntary exercise is important; horses are willing to stay out of their stalls longer if other horses are present and will show compensatory behavior only if other horses are present. These finding have implications for optimizing turnout time for stalled horses.

Training

Does Attention make the Difference? Horses’ Response to Human Stimulus After 2 Different Training Strategies

Paolo Baraglia, Chiara Maritia, Leonardo Petria, Francesco De Giorgiob, Claudio Sighieria

Journal of Veterinary Behavior: Clinical Applications and Research

Volume 6, Issue 1, Pages 31-38, January 2011

We hypothesized that in an open environment, horses cope with a series of challenges in their interactions with human beings. If the horse is not physically constrained and is free to move in a small enclosure, it has additional options regarding its behavioral response to the trainer. The aim of our study was to evaluate the influence of 2 different training strategies on the horse’s behavioral response to human stimuli. In all, 12 female ponies were randomly divided into the following 2 groups: group A, wherein horses were trained in a small enclosure (where indicators of the level of attention and behavioral response were used to modulate the training pace and the horse’s control over its response to the stimuli provided by the trainer) and group B, wherein horses were trained in a closed environment (in which the trainer’s actions left no room for any behavioral response except for the one that was requested). Horses’ behavior toward the human subject and their heart rate during 2 standardized behavioral tests were used to compare the responses of the 2 groups. Results indicated that the horses in group A appeared to associate human actions with a positive experience, as highlighted by the greater degree of explorative behavior toward human beings shown by these horses during the tests. The experience of the horses during training may have resulted in different evaluations of the person, as a consequence of the human’s actions during training; therefore, it seems that horses evaluate human beings on daily relationship experiences.

Trailer-Loading of Horses: Is there a Difference Between Positive and Negative Reinforcement Concerning Effectiveness and Stress-Related Signs?

Payana Hendriksen, Katrine Elmgreen, Jan Ladewig

Journal of Veterinary Behavior: Clinical Applications and Research

Volume 6, Issue 5, Pages 261-266, September 2011

The traditional way to train horses is by the application of negative reinforcement (NR). In the past few years, however, the use of positive reinforcement (PR) has become more common. To evaluate the effectiveness and the possible stressor effect of the 2 training methods, 12 horses showing severe trailer-loading problems were selected and exposed to trailer-loading. They were randomly assigned to one of the 2 methods. NR consisted of various degrees of pressure (lead rope pulling, whip tapping). Pressure was removed as soon as the horse complied. PR horses were exposed to clicker training and taught to follow a target into the trailer. Heart rate (HR) was recorded every 5 seconds and behavior denoting discomfort was observed using one-zero sampling with 10 seconds sampling intervals. Training was completed when the horse could enter the trailer upon a signal, or was terminated after a maximum of 15 sessions. Of the 12 horses, 10 reached the criterion within the 15 sessions. One horse was eliminated from the study because of illness and 1 PR horse failed to enter the trailer. A Mann–Whitney U-test indicated that the horses trained with NR displayed significantly more discomfort behavior per training session than horses trained with PR (NR: 13.26 ± 3.25; PR: 3.17 ± 8.93, P < 0.0001) and that horses in the PR group spent less time (second) per session to complete the training criterion (NR: 672.9 ± 247.12; PR: 539.81 ± 166.37, P < 0.01). A Mann–Whitney U-test showed that no difference existed in mean HR (bpm) between the 2 groups (NR: 53.06 ± 11.73 bpm; PR: 55.54 ± 6.7 bpm, P > 0.05), but a Wilcoxon test showed a difference in the PR group between the baseline of HR and mean HR obtained during training sessions (baseline PR: 43 ± 8.83 bpm; PR: 55.54 ± 6.7 bpm, P < 0.05). In conclusion, the PR group provided the fastest training solution and expressed less stress response. Thus, the PR procedure could provide a preferable training solution when training horses in potentially stressing situations.

Using Differential Reinforcement to Improve Equine Welfare: Shaping Appropriate Truck Loading and Feet Handling

Charlotte Slater, Simon Dymond

Behavioural Processes

Volume 86, Issue 3, Pages 329-339, March 2011

Inappropriate behavior during common handling procedures with horses is often subject to aversive treatment. The present study replicated and extended previous findings using differential reinforcement to shape appropriate equine handling behavior. In Study 1, a multiple baseline across subjects design was used with four horses to determine first the effects of shaping target-touch responses and then successive approximations of full truck loading under continuous and intermittent schedules of reinforcement. Full loading responses were shaped and maintained in all four horses and occurrences of inappropriate behaviors reduced to zero. Generalization of the loading response was also observed to both a novel trainer and trailer. In Study 2, a changing criterion design was used to increase the duration of feet handling with one horse. The horse’s responding reached the terminal duration criterion of 1 min and showed consistent generalization and one-week maintenance. Overall, the results of both studies support the use of applied equine training systems based on positive reinforcement for increasing appropriate behavior during common handling procedures.

Fostering Adherence to Horse Behaviour Counselling

Ruth Jobling, Emma Creighton

Journal of Veterinary Behavior: Clinical Applications and Research

Volume 6, Issue 5, Pages 276-286, September-October 2011

Counseling services that aim to improve understanding of horse–human interactions are on the frontline of the horse welfare agenda. The aim of this research was to determine characteristics of horse owners seeking advice about their horse’s behavior that predicted their adherence to that advice. The established science of human behavioral change has largely been applied in the field of health psychology to identify predictors of behavior. A thorough review of human behavioral change literature identified 10 cognitive variables (e.g., attitude toward horse behavior counselors) that had the potential to predict adherence to the advice of a horse behavior counselor. Established self-report questionnaire methodology was adopted to survey an opportunistic sample of 52 clients of horse behavior counselors before they received the advice (initial cognitive profile), 10 days after (post-communication changes), and at 3-month follow-up (long-term changes). Data were preliminarily analyzed using correlation analyses and subsequently, multiple regression analyses were used to generate a model for adherence. Horse behavior counselors cannot influence what clients perceive when they come into the process, but are able to influence cognitive variables during the communication. The amount of post-communication change in value of the outcome of adhering to the advice (β = 0.338, P = 0.033) and attribution of the horse’s behavior problem to external factors (e.g., facilities, time; β = 0.309, P = 0.050) were significant elements of a multiple regression analysis that explained 23.6% of the variance in adherence 10 days after the communication (F2,35 = 6.700, P = 0.003). At 3-month follow-up, there were no associations between adherence and the earlier cognitive profiles, but clients who showed a 3-month increase in positive attitude toward horse behavior counselors were more likely to show long-term adherence (r = 0.389, P = 0.019). Horse behavior counselors may benefit clients by demonstrating the effects of their advice early in the communication, so that clients value their efforts to adhere to the advice and continue to do so. Horse behavior counselors may also foster adherence to their advice by emphasizing external causes of the horse’s behavior problem, which clients may find more controllable than internal causes such as their level of skill or fear. Developing the client’s perception of a controllable cause of their horse’s behavioral problem may build confidence in their ability to address the problem and encourage adherence.

Thanks for reading.

Equine Science News 1 and Other Useful Resources

January 30, 2014January 30, 2014 Skynetlikesponies

Abstracts

Attributing attention: the use of human-given cues by domestic horses (Equus caballus)

Leanne Proops and Karen McComb

Recent research has shown that domestic dogs are particularly good at determining the focus of human attention, often outperforming chimpanzees and hand-reared wolves. It has been suggested that the close evolutionary relationship between humans and dogs has led to the development of this ability; however, very few other domestic species have been studied. We tested the ability of 36 domestic horses to discriminate between an attentive and inattentive person in determining whom to approach for food. The cues provided were body orientation, head orientation or whether the experimenters’ eyes were open or closed. A fourth, mixed condition was included where the attentive person stood with their body facing away from the subjects but their head turned towards the subject while the inattentive person stood with their body facing the subject but their head turned away. Horses chose the attentive person significantly more often using the body cue, head cue, and eye cue but not the mixed cue. This result suggests that domestic horses are highly sensitive to human attentional cues, including gaze. The possible role of evolutionary and environmental factors in the development of this ability is discussed.

Link – http://www.springerlink.com/content/v277039731080470/

Post-conflict friendly reunion in a permanent group of horses (Equus caballus)

Alessandro Cozzi, Claudio Sighieri, Angelo Gazzano, Christine J. Nicol and Paolo Baragli

Gregarious animals living in permanent social groups experience intra-group competition. Conflicts over resources can escalate into costly aggression and, in some conditions, non-dispersive forms of conflict resolution may be favoured. Post-conflict friendly reunions, hence reconciliation, have been described in a variety of species. The aim of this study was to explore, for the first time, the occurrence of reconciliation in a group of domestic horses (Equus caballus) and learn more about strategies used to maintain group cohesion. The behaviour of seven horses living as permanent group in an enclosure for at least 2 years was observed by video for 108h from June to August 2007. We used a Post-Conflict/Matched Control method to assess the existence of reconciliation and third-party affiliation. Behaviours recorded Post-Conflict, or during Matched Control periods, were classified as affiliative based on previous descriptions of visual communication patterns in horses. The proportion of attracted pairs over total post-conflict situations was significantly greater than the proportion of dispersed pairs, both during dyadic interactions (p<0.001) and during triadic interactions (p=0.002). The results of the present study show that both dyadic reconciliation and third-party post-conflict affiliative interactions form important social mechanisms for managing post-conflict situations in horses.

Link – http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T2J-50M1RT9-1&_user=10&_coverDate=10%2F31%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1459832741&_rerunOrigin=scholar.google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=2e607ef1b0e15c2771e7ecc1d183f723&searchtype=a

Websites

The Horse (http://www.thehorse.com/)

The Horse website is free to join and has many articles on both equine health and horse behaviour written by professional in equestrian industry.

This is a particularly interesting article on ‘licking and chewing’ behaviour in horses which explores a possible biological explanation for this little understood behaviour. – http://www.thehorse.com/ViewArticle.aspx?ID=6346

Useful and Informative Forums

Equi-click (http://equi-click.proboards.com/index.cgi)

Whether you are a positive reinforcement pro or are thinking of trying clicker training for the first time, equi-click is a friendly community of well informed and supportive individuals. There are members from many backgrounds who contribute a wide range of scientific knowledge and practical know how. The forum requires you to register before you can view the content but it is well worth joining.

Thinking Horsemanship Forum (http://www.network54.com/Forum/235380/)

‘The Thinking Horsemanship Forum is for anyone (beginner, professional or somewhere in-between) who would like to understand more about the behaviour of horses (and other animals) and how they learn. We prefer to study the published science into learning and behaviour and its practical application to training than to follow any commercial methodology. In particular we aim to use positive reinforcement (sometimes although not always via clicker training) and increased motivation in order to train our horses, rather than the traditional methods of increasing pressure.

We welcome discussion on all topics within the areas of learning and behaviour and encourage lively debate over the various methods of equine training. But it should be made clear that no personal attacks or criticism will be tolerated and such posts will be edited or removed. We would also like to make it clear that we are not qualified experts offering advice and are not affiliated to any such experts or commercial organization. We are purely interested individuals who would like to learn more for the benefit of our horses.’

Joining The Equine Independent on Facebook

Please join our facebook group at http://www.facebook.com/group.php?gid=143081082369349&ref=ts

By Emma Lethbridge

The Battle with Obesity

January 30, 2014January 30, 2014 Skynetlikesponies

Summer is a great time for riders and horse owners alike, the long days and hopefully sunny weather bring greater opportunities for spending time with our much loved, four-legged friends. However, for some horse and pony owners summer can also be a worrying time and the start of an ongoing battle with their horse’s waistline. Despite our best intentions summer comes and our horse’s stomachs begin to expand like balloons at a birthday party. Some horses come out of winter the perfect weight but can start to inflate the minute the first spring grass appears, for others the issue of weight is a constant factor, especially for those with pony or cold blood genes in their DNA. If you own a horse who is a ‘good doer’ and he can seemingly live off air alone, it can seem like no management strategy or exercise regime will stop the spread. So what are the real risk factors of obesity and how can we prevent our horse’s becoming overweight this summer?

Obesity, in both horses and humans, is becoming an epidemic in the UK. The horse charity, World Horse Welfare, estimates that between 35 and 45 per cent of the UK’s 1.35million horses are obese^[1]. There are many worrying disorders that obesity is associated with, including; Laminitis, Equine Metabolic Syndrome and oxidative stress^[2]. All of the above disorders are of grave concern to owners! Laminitis is inflammation of the digital laminae of the hoof. The digital laminae are necessary for suspension of the skeleton within the hoof and spread the concussive forces experienced by the hoof during the horse’s locomotion. Inflammation of the laminae weakens the hoof and can have devastating effects on the horse’s physiology included; sinking and rotation of the coffin bone (known as founder), separation of the hoof wall from the hoof capsule, rotation of the coffin bone and penetration of the coffin bone through the sole of the hoof^[2]. These complications of Laminitis can cause permanent lameness and loss of use and can, in the worst cases, result in euthanasia.

Equine Metabolic Syndrome (EMS) is characterised by obesity, insulin resistance and intermittent bouts of Laminitis^[2]. Obese horses suffering with EMS become gradually more resistant to the action of insulin – insulin is a hormone which triggers cells in the liver, muscles and fat to take up glucose from the blood stream and store it as glycogen. This resistance to insulin consequently causes abnormally high levels of insulin to be secreted when the horse ingests food, especially foods high in sugars such as concentrate. In both horses and humans, insulin resistance seems to be correlated with obesity and the altered metabolism of fats^[3]. However, unlike in the human species, insulin resistance in horses due to obesity is very rarely type 2 diabetes (diabetes in horses is usually only associated with Cushing’s syndrome), instead insulin resistance is postulated to be a contributing factor to Laminitis and potentially certain vascular diseases^[3].

Laminitis and EMS are not the only concerns for the owners of horses who put on weight easily. Several adverse health effects can be correlated with the horses gain of fat deposits. The horse may become intolerant of exercise and his athleticism will be compromised. Just as obese humans can experience oxidative stress, fatigue and increased concussion on joints during exercise, horses can also experience these consequences of obesity. The performance of horses competing in races of duration 1 mile to 160km has been found to correlate to the horse’s body condition^[4-6]. The obese horse may also experience thermoregulatory difficulty, although fat deposits will insulate a horse during the winter months, in the summer excess fat can prevent the horse from effectively dissipating heat resulting in the horse overheating^[7]. Finally, abnormal reproductive performance has also been observed in obese mares ^[8], obesity can cause unnecessary complications in pregnancy and is therefore a welfare concern for both mare and foal. The risks of horse obesity are very worrying for horse owners so why are so many horses becoming obese in the UK?

Although ignorance on behalf of the horse owner is sometimes the underlying cause of equine obesity, most owners are aware when their horses are becoming overweight. Even the least observant owner can see their horse’s stomach increasing in girth, the neck becoming larger and developing a crest, and fat deposits occurring on the shoulders and flanks, but often the owner is struggling to set up a management regime that can control the weight of the horse. Owners are often restricted by factors such as; the residence of the horse, the management of the horse’s pasture or other environmental factors. But do not despair, here are a few ideas which could help to prevent the summertime spread this year.

1. Knowing how much you horse should weigh, finding an accurate way to measure your horse’s weight and keeping a record of change.

The first thing you will need to know when you embark on the battle with obesity is your horse’s ideal weight. Without a goal weight for your horse any measurement of the horse’s weight is going to be arbitrary. Although all horses differ with regards to their ideal weight, approximate ideals for your horse’s type and height can be found below. For each height range there is a range of ideal weights, if your horse is the top end of the height range or a draught bred then the horse’s ideal weight will be the top end of the range, and vice versa.

Height in hands	11	12	13	14	15	16	17
Ideal weight in kg	120-230	230-290	290-350	350-420	420-520	520-600	600-725

(Adapted from Baileys Horse feeds ^[9])

Once you know your horse’s ideal weight you will need to be able to measure the horse’s weight. There are many ways to measure a horse’s weight, some more accurate than others. The most accurate method of measuring a horse’s weight is a weighing bridge, however unless you are liveried at a very well equipped yard or have convenient access to veterinary facilities it is unlikely that you will have access to a weigh bridge.

A more common method of measuring a horse’s weight is by using a weight tape. Weight tapes are placed around the girth of the horse, just behind the withers, and give an estimation of the horse’s weight based on the circumference of the girth . The accuracy of these tapes is debatable however, the tape provides a quantitative measure of weight which can be recorded and which will provide notice of the horse’s weight changing over time. Weight tapes can be brought from most equestrian stores, and on occasion tapes specifically designed for draught horses and ponies can be acquired. Buying a tape designed for your horse’s body type will increase the accuracy of the measurement.

As an alternative measure of the horse’s weight and condition there are body condition scoring systems, one of the most popular is based on work by Henneke et al (1983)^[10]. Henneke et al’s body condition scoring uses the observation and ranking of the fat tissue present on specific areas of the body to score the condition of the horse. The areas observed for the accumulation of fatty tissue are; the neck, ribs, back, shoulder, wither and the top of the tail. When all the areas are taken into consideration an overall condition score, between 1 and 9, is attributed to the horse – 1 being of very poor condition with no fatty tissue present in the scored areas and 9 being of obese condition with significant fatty deposits visible on the . A picture chart explaining Heneke’s body condition scoring can be found at –http://www.admani.com/allianceequine/images/bodyconditionscoring/horse%20body%20condition%20score%20card.pdf , this picture chart is a good summary of the observations that should be made during condition scoring. A printable record sheet for Henneke et al’s body condition scoring mechanism can also be found at this link – http://www.blm.gov/pgdata/etc/medialib/blm/wo/Information_Resources_Management/policy/im_attachments/2009.Par.52473.File.dat/IM2009-041_att1.pdf

There are potential problems with using body condition scoring as a method of weight measurement in horses. Scoring body condition is a subjective method and it is therefore possible for owners to over or under score their horses and, if no additional methods of weight measurement are used, it is sometimes difficult to ascertain whether the horse is indeed of a healthy weight. Ideally two or three people should score the horse independently and the middle score taken to be correct, such a precaution will help to minimise the effect of subjective bias. The body score of the horse can be recorded and over time any change in the horse’s condition can be monitored accordingly.

Whichever method of weight measurement you decide to use with your horses, try to keep a record at least once a month of the horse’s weight. This record keeping will allow you to see changes in the horse’s condition early and allow you to change his management before serious complications arise.

2. Cutting out the concentrate feed!

This one may seem obvious, but if your horse is overweight it is not necessary to supplement the horse’s roughage feed with concentrate! Removing concentrate feed, and therefore unnecessary calories, from the diet of the horse will help to prevent, or treat, obesity. If the horse is feed ad-lib, quality roughage including pasture, and is a good weight it is not necessary to supplement the horse’s diet with calorie-dense, grain concentrate. Should the horse’s pasture and roughage be of poor quality it may be a prudent idea to add a vitamin and mineral supplement to the horse’s feed, this will prevent any dietary malnutrition. As long as the horse maintains weight and does not become thin, and is not in a heavy exercise regime, i.e. intermediate eventing or above, the horse does not require extra calories. Should the horse be currently in a routine where he is used to receiving concentrate meals at certain times and will become distressed if his routine is changed then some molasses-free chaff or grass chop can be feed at these times to placate him.

3. Pasture maintenance

There are many aspects of pasture maintenance that can be managed to help combat obesity and weight gain in the horse. Below I will tackle the most important factors of pasture maintenance that can be managed by horse and land owners –

The right grass?

Many grassland species have been selectively produced to feed domestic livestock on intensive grazing patterns, as such many grass species commonly found in horse grazing are high in sugars. Grass designed to keep livestock at a good weight is often too rich for horses who are designed by evolution to each a great amount of poorer roughage. See below abstract by Menard et al (2001)^[11] on the comparative forage intake of cattle and horses.

“Equids are generalist herbivores that co-exist with bovids of similar body size in many ecosystems. There are two major hypotheses to explain their co-existence, but few comparative data are available to test them. The first postulates that the very different functioning of their digestive tracts leads to fundamentally different patterns of use of grasses of different fibre contents. The second postulates resource partitioning through the use of different plant species. As domestic horses and cattle are used widely in Europe for the management of conservation areas, particularly in wetlands, a good knowledge of their foraging behaviour and comparative nutrition is necessary.

In this paper we describe resource-use by horses and cattle in complementary studies in two French wetlands. Horses used marshes intensively during the warmer seasons; both species used grasslands intensively throughout the year; cattle used forbs and shrubs much more than horses. Niche breadth was similar and overlap was high (Kulczinski’s index 0·58–0·77). Horses spent much more time feeding on short grass than cattle. These results from the two sites indicate strong potential for competition.

Comparative daily food intake, measured in the field during this study for the first time, was 63% higher in horses (144 gDM kg W−0·75 day−1) than in cattle (88 gDM kg W−0·75 day−1). Digestibility of the cattle diets was a little higher, but daily intake of digestible dry matter (i.e. nutrient extraction) in all seasons was considerably higher in horses (78 gDM kg W−0·75 day−1) than in cattle (51 gDM kg W−0·75 day−1). When food is limiting, horses should out compete cattle in habitats dominated by grasses because their functional response is steeper; under these circumstances cattle will require an ecological refuge for survival during winter, woodland or shrubland with abundant dicotyledons.

Horses are a good tool for plant management because they remove more vegetation per unit body weight than cattle, and use the most productive plant communities and plant species (especially graminoids) to a greater extent. They feed closer to the ground, and maintain a mosaic of patches of short and tall grass that contributes to structural diversity at this scale. Cattle use broadleaved plants to a greater extent than horses, and can reduce the rate of encroachment by certain woody species.”

Menard et al (2001)

As horses can consume great amounts of forage it is vital that the high-sugar, easily digestible and nutrient rich grass varieties fed to domestic livestock species are not feed in high quantity to horses. Obesity and laminitis will be difficult to avoid on rich grazing without restricting grazing, which in turn would be detrimental to the welfare of the horse. Sugars present in grass species, especially fructans have been correlated with laminitis in horses. Below is an informative short article on fructans from www.equinescienceupdate.co.uk.

“Recent studies suggest that fructans might be involved in pasture-induced laminitis in horses. Fructans are storage molecules produced by the grass when it produces more sugars by photosynthesis than are needed for immediate use. Fructans are poorly digested in the foregut of the horse. If large quantities reach the hindgut they are rapidly fermented by the microorganisms, leading to a cascade of events that may result in laminitis.

In a three year study Jürgen Grässler and Uwe von Borstel, working at the Landwirtschaftskammer in Hannover, Germany, looked at fructan content in the species of grasses that are commonly found in horse pasture. They harvested grass samples every two or three weeks during the growing season. Samples were collected at 11.00 each morning to prevent the results being influenced by time of day.

Dr Grässler presented their findings at the Equine Nutrition Conference held earlier this month in Hannover. They found that Lolium perrene (Perennial ryegrass) and Lolium multiflora (Italian ryegrass) contain the highest amounts of fructans – an average throughout the year of 5.7% on a dry matter basis. However, they found that the fructan content varied throughout the year, being highest in May and October. The fructan content fell during the summer. They also found a difference between strains of perennial ryegrass. One strain (“Anton”) had the highest fructan level of 14.2%DM in autumn 2003 and 13.6% DM in spring the same year.

All other pasture grasses contained low fructan concentrations – on average about 3.5% DM. Again, the highest fructan concentration was found in the first growth in May and in October. The fructan content of the grass was lowest during the summer.

The second part of the study looked at the fructan content of grass mixes that might be used for horse pasture. Grässler and von Borstel found that mixtures with a high proportion of Lolium perrene gave the highest fructan levels . The highest levels were found in pastures containing only Lolium perrene (15.2%). During the growing season the highest fructan content was measured in late June (11.4% DM average) and in October.

Grässler and von Borstel conclude that grass mixes with high amounts of Lolium perrene may contain high fructan concentrations, especially in spring and autumn, and are less suitable for feeding horses predisposed to laminitis.

To minimise the risk of laminitis they suggest that grass mixtures with reduced quantities of Lolium perrene should be used. Pastures with forage grasses such as Alopecurus pratensis (Meadow Foxtail) and Phleum pratense (Timothy) as the main components are suitable to produce low fructan concentrations.

Reference: Fructan content in pasture grass. Jürgen Grässler and Uwe von Borstel. Proceedings Equine Nutrition Conference. Pferdeheilkunde (2005) 21, 75 – 76.”^[12]

The key message of the above article is; when planning the reseeding of your pasture please consider the grass species you are using and choose low-sugar grass species, such as Meadow Foxtail and Timothy, which will protect your horses against obesity, insulin resistance and Laminitis. Herbs and legumes can also be included for variety and additional vitamin and mineral availability. Sugar-dense grasses used to feed domestic livestock, such as dairy cattle, should be avoided as they are not suitable for healthy horse grazing. Rye grass is the typical example and is currently very common in the pastures of Britain’s horses. If you are at the mercy of a land owner it may be possible through democratic negotiation to encourage the seeding of horse friendly grass species.

Pasture fertilisation

Traditionally pasture fertilisation is recommended in the spring and autumn months. It is suggested that proper fertilisation will provide pasture with the nutrients to produce a good quantity of grass cover, minimising weed growth. In addition it is postulated that the nutrients needed to provide horses with a healthy diet are also infused into the soil during fertilisation. However, the relationship between fertilisation and grass nutrition is not straight forward, especially when considering non-structural carbohydrate concentrations (sugars). It is often assumed that fertiliser increases the sugar content of grass, however, it is well noted in scientific journals that grass grown in an environment deficient in either nitrogen or phosphorus is observed to be significantly higher in sugars than grass grown in fertilised conditions ^{[13, 14, 15, 16]}. The discovery of this correlation between nitrogen availability and the sugar concentration in grass has led to the postulation that nitrogen maybe a limiting factor for growth and therefore if the grass becomes deficient in nitrogen, growth stops and, rather than being used for the production of new plant matter, fibre and energy, the sugars accumulate in the grass^[17].

In her 2005 paper titled – A Review of Unlikely Sources of Excess Carbohydrate in Equine Diets, Kathryn Watts considers data collected on the effect of pasture fertilisation on the non-structural carbohydrate (NSC) concentrations of grass, and how pasture should managed to prevent an excess in sugar in the equine diet^[17]. She writes “The following data was collected from the first cutting of forage from an established paddock of irrigated pasture at Rocky Mountain Research & Consulting, Inc. Each treatment was replicated 4 times in a randomized block design. The species represented are mostly Paddock meadow brome and Garrison meadow foxtail, which are standard commercial varieties in the area. Ammonia nitrate was broadcast in March, and irrigation was applied as needed for optimum growth to both fertilized and unfertilized plots. When the paddock was starting to head the end of May, samples for NSC were collected 4 PM, frozen immediately, and shipped frozen for analysis. A light frost occurred the night before sampling. The next day, 2 sq yards of plant material were hand clipped to ground level from each plot, and dried in an oven to obtain dry matter yield. The plots fertilized with ammonia nitrate yielded 3 times more dry matter, and were 29% lower in NSC concentration than unfertilized. This inverse relationship between nitrogen content and NSC concentration corroborates that found in plant science literature.

The determination as to whether NSC concentration or pounds of NSC per acre is more important will be dependent on how the individual horse’s intake is managed. If a horse has continual access to pasture, it is possible to limit grass intake by starving the grass for nitrogen and overgrazing such that the amount of available forage does not exceed or even meet caloric needs. In this scenario, additional hay is often required. Because hay is generally lower in NSC than fresh grass, the higher concentration of NSC in nitrogen deficient grass may be offset by the lower concentration generally found in hay. In this type of situation, susceptible horse’s may be at increased risk of over indulging if the pasture is fertilized or irrigated, or a drought breaking rain occurs, which would then create more pounds of NSC per acre, while removing the limitations to intake imposed by slow grass growth.

If the caretaker were limiting intake by restricting access to grass, by use of grazing muzzle, portable fencing, or removal to a dry lot for part of the day, then fertilization, which decreases the concentration of NSC per mouthful of grass, would be the best option.” ^[17]

When considering whether it is healthier for your horses to fertilise your paddock or to leave it to grow organically it is necessary to consider whether the higher yield of grass obtained through fertilisation is likely to cause your horse to have higher sugar in his diet than the lower yield, higher sugar concentration grass of organic pasture? If your horse’s residential property has a low horse-acreage ratio, then it is possible that the high yield gained by fertilisation will create to much pasture for the horses to graze without becoming overweight. However, if there are a significant amount of horses grazing the pasture of your horse’s residence the extra grass yield of fertilised pasture should be spread between enough animals that the lower sugar concentration of fertilised grass is beneficial. Optimum fertilisation is a balancing act, one that must be considered carefully by horse owners.

References

[1] http://www.worldhorsewelfare.org/

[2] Johnson P.J., Wiedmeyer C.E., Messer N.T., Ganjam V.K. Medical Implications of Obesity in Horses—Lessons for Human Obesity. J Diabetes Sci Technol. 2009; 3(1): 163–174.

[3] Hoffman R.M., Boston R.C., Stefanovski D, Kronfeld D.S., Harris P.A. Obesity and diet affect glucose dynamics and insulin sensitivity in Thoroughbred geldings. J Anim Sci. 2003;81(9):2333–2342.

[4] Kearns C.F., McKeever K.H., Kumagai K., Abe T. Fat-free mass is related to one-mile race performance in elite standardbred horses. Vet J. 2002;163(3):260–266

[5]Lawrence L.M., Jackson S., Kline K., Moser L., Powell D., Biel M. Observations on body weight and condition of horses in a 150-mile endurance ride. J Equine Vet Sci. 1992;12:320–324.

[6]Garlinghouse S.E., Burrill M.J. Relationship of body condition score to completion rate during 160 km endurance races. Equine Vet J Suppl. 1999;30:591–595.

[7] Cymbaluk N.F., Christison G.I. Environmental effects on thermoregulation and nutrition of horses. Vet Clin North Am Equine Pract. 1990;6(2):355–372.

[8] Henneke D.R., Potter G.D., Kreider J.L. Body condition during pregnancy and lactation and reproductive efficiency of mares. Theriogenology. 1984;21:897–909.

[9] http://www.baileyshorsefeeds.co.uk/feedingexplained/calculator.htm

[10] Henneke D.R., Potter G.D., Kreider J.L., Yeates B.F. (1983). Relationship between condition score, physical measurements and body fat percentage in mares. Equine Vet J. 15(4):371-2

[11] Menard C., Duncan P., Fleurance G., Georges J-Y., Lila M. (2001). Comparative foraging and nutrition of horses and cattle in European wetlands. Journal of Applied Ecology. 39 (1); 120-133.

[12] Article at http://www.equinescienceupdate.co.uk/fructan.htm on the paper- Fructan content in pasture grass. Jürgen Grässler and Uwe von Borstel. Proceedings Equine Nutrition Conference. Pferdeheilkunde (2005) 21, 75 – 76.

[13] Smith D. Nonstructural Carbohydrates. In Butler G.W., Bailey R.W. ed. Chemistry and Biochemistry of Herbage, vol 1. London: Academic Press, 1973;105-155.

[14] Belesky D.P., Wilkinson S.R., Stuedemann J.A. The influence of nitrogen fertilizer and Acremonium coenophialum on soluble carbohydrate content of grazed and non-grased Festuca arundinace., Grass Forage Sci 1991;46:159-166.

[15] Donaghy D.J., Fulkerson W.J. The impact of defoliation frequency and nitrogen fertilizer application in spring on summer survival of perennial ryegrass under grazing in subtropical Australia, Grass Forage Sci 2002;57(4):351.

[16] Morvan-Bertrand A., Boucaud J., Prud’homme M. Influence of initial levels of carbohydrates, fructan, nitrogen and soluble proteins on regrowth of Lolium perenne . L. cv. Bravo following defoliation. J Exper Bot 1999;50:1817-1826.

[17] Watts K.A. A Review of Unlikely Sources of Excess Carbohydrate in Equine Diets. Journal of Equine Veterinary Science. 2005; 25(8): 338-344