Stable 'vices' in horses, negative habitual behaviour that can devalue a thoroughbred, may be linked to feeding practices according to researchers. Anna Nolan reports.
'We pride ourselves in Ireland on how well our horses learn, but we don't know how they learn," says Prof Sean Arkins, professor of equine science at the University of Limerick. "In fact, equine behaviour is under-researched generally worldwide."
UL is doing something about this however with a number of research projects looking at horse behaviour. One has identified "handedness" in horses and provides an explanation for why male horses often make better jumpers. Another involves potentially harmful characteristic behaviours in horses which have now been linked to feeding practices.
Professor Arkins advised researcher Jack Murphy on a study of visuo-spatial ability in horses. Mr Murphy, in a recent paper in Applied Animal Behaviour Science, showed that, on average, male horses had superior ability to distinguish depth than females.
A mature PhD student funded by the Irish Research Council for Science, Engineering and Technology, Murphy had worked with horses for several years before studying at UL, and had noticed the strong preference for male horses in show-jumping, dressage and eventing.
"Male horses are bigger and have more muscles, but I was not satisfied that this was the only reason, so I looked at depth perception," said Murphy.
He devised tests, with advice on the apparatus from Thomas Waldmann, also of UL, in which the horses had to find food. The food was placed in four stalls, with barriers to access, but only one barrier was shallow enough to allow the horses to reach the food. The barriers were moved around, and six different tests were used. Overall, the males strongly out-performed the females.
Murphy thinks that depth perception may be linked to having a more developed right hemisphere of the brain, as in humans. He has recently been looking at laterality, that is whether the horse is right-handed or left-handed - left-handedness is linked to using the right side of the brain.
In a paper about to be published in Applied Animal Behaviour Science, he reports that of 20 male and 20 female horses he studied, 65 per cent of the males were predominantly left- handed, and 75 per cent of the females were strongly right- handed. He was advised on test procedures by Alistair Sutherland of UL.
Arkins says research on equine welfare is also important for UL. In this area, Noelle Carroll has carried out the first study in Ireland of "stereotypies" in thoroughbred horses in race training.
Some domesticated horses weave around, walk up and down beside a fence or inside a stable, suck air, chew wood or display other behaviour not seen in wild horses. These behaviours, formerly called "stable vices", are now called "stereotypies".
As well as equine welfare, there are financial considerations. Some stereotypies such as pacing lead to loss of weight, and if a horse is sold at auction and then found to display stereotypies, it can be returned.
Carroll, whose research was supported by IAWS, carried out in-depth interviews with a random sample of 105 horse trainers, representing 28.5 per cent of all trainers in the State. The interviews covered 1,368 racehorses, 33.5 per cent of all thoroughbred horses in training in Ireland. She followed up with study and videotaping of some horses in their stables.
"Factors that led to stereotypies were the management regime, the amount of feed the horses were given and the frequency with which they were fed."
A wild horse forages for between 10kg and 20kg of feed daily. In the stable, however, many horses are given an average of 4.9kg of hay and other equivalent food and almost 7kg of concentrate.
"In the wild, the horse forages for 80 per cent of the day and 70 per cent of the night," she said. "When fed a lot of concentrates they have too much free time, and the more they are given the more they exhibit stereotypies."
She also found that the more the horse was out of the stable, and the more time it spent with other horses, the fewer stereotypies there were. And horses trained six days a week with one day off had fewer stereotypies than those trained every day.