Precis andrew hemmings

CHARITABLE TRUST • Andrew Hemmings

Pound of horseflesh teaches lots about animal behaviour Andrew Hemmings of the Royal Agricultural College, Cirencester, used a Farmers Club Charitable Trust Scholarship to visit Rome, Edinburgh and Aberystwyth to examine the effects of stress on, primarily, horses, and whether they obtain pleasure from ‘bad’ habits developed to alleviate such stress. This précis of his report makes fascinating reading.

THE INFAMOUS M6 was closed the only day in the year I didn’t listen to breakfast travel news, the only day I needed to get from Aberystwyth via Gatwick to Rome.

Consequently, as the parking compound at Gatwick neared, the flight in question banked into the dark November sky… without me on it.

Feelings were mixed; from anger, through helplessness to elation. Why elation?

Because I have a long standing, totally irrational fear of flying.

This aside, as part of my FCCT-sponsored study I needed to get to Rome to deliver a presentation at the Institute of Psychobiology. The overall aim was to extend knowledge of brain function in relation to farm animal behaviour and welfare.

And so, safely ensconced on the next flight, I considered my fate within this oversized, flying cigar tube. A fear of flying can be attributed to a lack of control… if we were to plunge from 30, 000 feet, there’s very little anyone could do about it. Because of this, the experience of flying can be perceived as ‘stressful’.

Coping tools All animals posses ‘tools’ or responses which allow them to cope with stressful circumstances. For example, behavioural responses which help animals escape predation, or immune responses to fight off invading pathogens. In other words, animals have evolved systems which allow them to ‘cope’ with the natural environment in which they live.

When taken out of a natural state and placed in domestic confines, these ‘coping tools’ may fail. It’s at this point that the animal can suffer reduced welfare. However, one of the amazing facets of life, as we know it, is its inherent adaptability and diversity.

Because of differences in individual personality and physical make-up, some cope better with stress than others, or some use different coping tools than others. For example, the

first thing I do when our perilous ascent is complete is order a large G&T (despite the £4.50 price tag). This is a coping response.

Other individuals may use chocolate, or more antisocial (and illegal) substances to cope with stress. The guy behind me has his eyes tightly closed and his fists firmly clenched, while the lady to the right maintained a constant stream of nervous chatter, making me wish I’d packed a parachute. Again, coping responses, but all fairly different.

Those of you who have visited any one of our country’s zoos will, perhaps, have noticed animals performing abnormal repetitive behaviours: pacing in big cats, repetitive swimming in polar bears, and elephants that rock (musical preference aside). Such actions are commonly known by scientists as ‘stereotypies’ or stereotypic behaviours.

Similar movements are also observed in our common farm species, such as pigs (bar chewing), and cattle (tongue rolling). So why do animals perform these stereotypic behaviours, which differ radically from anything observed in the natural environment?

Well, we can’t ask the animals, but we can ask humans, who can also be stereotypy prone.

Admit it, I bet some of you repetitively chew your finger nails or pace like caged tigers when under stress!

A prominent researcher in this field, Temple Grandin, is autistic and performs a kind of rocking stereotypy. She firmly believes that the rocking motion has a stress-reducing effect. In fact, when required to speak at international conferences, Temple admits to using her rocking ‘coping tool’ to alleviate the stress associated with public speaking.

Welfare question One main question arises here: Do animals also employ stereotypies in times of stress?

It’s an important welfare question that, so far, scientists have failed to answer.

It should also be mentioned, at this point, that those animals who do not develop stereotypy may be using other anti-stress responses, such as behavioural depression or withdrawal (a bit like the passenger with his eyes closed).

The Italian university system is somewhat different to ours, as literally anyone can walk from the street and into a lecture. A commendable system, although classes sometimes resemble a cross between a soup kitchen and Paddington Station at rush hour.

I stood in the university building facing the office door of my hero; Professor Simona Cabib, an expert in brain mechanisms controlling stereotypic behaviour in, wait for it, mice.

Anyway, Simona appeared and led us through several corridors and down multiple stairways thronged by students and vagrants (hard to tell the difference) until we reached

the basement labs where our presentation was to be heard. I had chosen to present information concerning stereotypies exhibited by the horse, mainly because they perform three distinct types of stereotypy: crib-biting, whereby the animal grasps a solid object with the incisors, flexes the neck muscles and produces a grunting sound; weaving, a lateral movement of the head, while shifting weight between both fore legs; and box walking, a repetitive circling of the stable confines.

Additionally, horses have always been close to my heart, having owned about five of the beasts down the years, mainly as part of profit-making exercises (less said about that the better… I was never a good judge of horse flesh. In fact, the only rich horse dealers I know at present are meat men.)

And, so, I discussed the ins and outs of equine stereotypy, and the fact that the only real difference between crib-biting, weaving, and box walking, and those behaviours performed by other species, is the way in which they are perceived by the owners.

Unwanted ‘vices’ Equine stereotypies are regarded as unwanted ‘vices’, which are contagious and performance-reducing. Despite neither evil being proven in the scientific press, up to 70% of horse owners make some attempt at stereotypy prevention.

Methods stem from electric stable doors, invasive operations, and the fitting of devices that hinder the neck movements required in crib-biting and weaving. While some of these practices have welfare considerations themselves, it is the prevention of a potential coping response that is most worrying. If cribbing is a stress-reduction tool, its prevention could leave the animal prone to the harmful effects of stress, such as stomach ulceration and depression of immune function.

To address the question of stereotypy function, a good friend from Aberystwyth University (Dr Sebastian McBride) and I had a closer look at the horse’s brain. The work conducted in Italy by Simona Cabib established that mice which perform stereotypic behaviours posses some well defined structural differences in two regions of the brain concerned with the generation of pleasurable sensation: the Nucleus Accumbens (NA), and Ventral Tegmental Area (VTA).

Both these areas are in contact with each other via bundles of nerve fibres. In fact, to generate a pleasurable sensation requires the flow of a brain hormone, or neurotransmitter, known as dopamine from the VTA into the NA. In the brains of those mice which had performed stereotypy, there are changes which mean that dopamine flows more readily from one region to the next, meaning that certain behaviours - which previously had no pleasurable feedback - over a period of time become ‘rewarding’.

Reward value

Given that these changes in the brain occur with stereotypy onset, it can be assumed that stereotypic behaviours have some reward value. This left me with the question: do similar differences occur in horses?

It also left me with the problem of finding brains from these horses, as being a welfarebased study, there was no way that animals were going to be sacrificed to meet these ends alone. Finally it was decided that horses already designated for slaughter would yield suitable samples.

Incidentally, there are several equine slaughter houses in the UK which do an excellent job of dispatching unwanted, potential welfare cases in a manner that is incredibly humane and welfare friendly.

Anyway, in order that I did not upset the meat production line, my place was the gut room, where the stomach and intestines would arrive for later disposal, where the acrid stench of fermented grass and faeces-to-be would enter the nose and literally attack the soul from within. Despite this, hacksaw in hand, brains were removed and immediately frozen for later analysis. All in all, the equine brain weighs approximately 1lb and is incredibly similar in structure to the human counterpart.

Meaningful experiment After 10 abattoir trips, enough brains had been collected to complete a meaningful experiment. But before lab analysis could begin, still more advice was required; this time from Edinburgh University, which thankfully did not require travel at the mercy of jet engines.

For an innocent Shropshire lad, used to delicacies such as fidget pie and fresh ale from the local brewery, Edinburgh was a bit of a change. From steak tartare through flambĂŠed lambs liver to sushi, the culinary roller coaster progressed, stopping only to sample cocktails which promoted abnormal behaviours on the night and reduced personal welfare in the morning.

Hedonism aside, the days spent in Scotland were incredibly useful, as a chap known as ‘Harry’ - a research worker and senior lecturer at the faculty of neuroscience - was happy to dedicate hours of his time towards my proposed experiment. Although he had never seen a horse brain, and refused to believe that horses are endowed which such organs, his work in the field of drug addiction used very similar methodologies, and tended to focus on the same brain regions (Nucleus Accumbens and Ventral Tegmental Area).

So, with this extra information in my head, and a few extra inches on the waist line, I journeyed to Aberystwyth, where the experimental work was to take place. Anyone who has set up an experiment from scratch will know the hard work required in the optimisation stage.

This took approximately four months, and at this point I must express sincere thanks to my long suffering employer, the Royal Agricultural College, for giving me this time away and for funding the experimental work. I’m glad that senior management at ‘the Royal’ recognises the importance of having research able staff in the tertiary education system, as there is nothing more rewarding than disseminating the results of personal research to students.

To cut short a long story, the equine experiments yielded similar data to that obtained in rodents, in that stereotypy horses displayed sensitised reward centres, which certainly suggests that these behaviours have hedonic qualities.

To confirm this conclusion, behavioural tests with live animals have also been conducted, which assume that, if crib-biting is rewarding, the horse should perform some form of work in order to crib.

Basically, all crib-biting surfaces in a stable were removed. When a crib-biting animal was placed in this stable, in order to obtain a cribbing surface it had to press a button (which is a form of work). If crib-biting is not a desirable commodity, animals will not be motivated to perform work to crib.

A total of six cribbers were used in this study, and in fact all pushed the button to obtain the cribbing surface. This certainly complements the results of the brain-based study, and suggests that this behaviour is rewarding. Therefore, physical prevention has the potential to significantly reduce the welfare of stereotypy-prone horses.

This work adds important knowledge to the ongoing stereotypy function debate. So, in my opinion, the hours spent removing brains in the stinking gut room are justified, as there’s certainly a lot to be learned from this particular pound of horseflesh!

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Andrew Hemmings can be contacted at the Royal Agricultural College, Cirencester, by emailing

Andrew.Hemmings@rac.ac.uk