An Australian forensic veterinary pathologist has found evidence that horses are not as “thick-skinned” as many believe, raising questions around whip use.
Dr Lydia Tong, who is with the New South Wales Department of Primary Industries, found that horse skin was thicker than human skin, but by less than 1 millimetre.
The difference, she said, was primarily in the deep collagen tissue, which sits below the superficial pain-sensing fibres.
“The horse epidermis – the very top-most layer of skin where the pain sensing nerves are found – was actually thinner than the human epidermis,” she told Catalyst, an Australian science show screened on ABC.
This meant that horses had fewer skin cells lying between the source of pain, such as a whip, and its sensitive nerve endings.
“In some ways you could therefore argue that when it comes to pain, the horse’s skin is thinner,” she said.
Tong conducted her research at the request of Catalyst, which posed the question: Is there any anatomical reason to believe that horses don’t feel pain like we do?
“This small pilot study suggests that horse skin really doesn’t have all the supposed ‘padding’ from pain that we often assume larger animals have,” she reported.
“And even more revealing than that, the skin of the body – where we whip horses – may have even more sensation than ours.”
Tong noted that while there was some information available about horse-skin thickness, it appeared that no-one had ever looked specifically at the pain-sensing fibres in the skin of horses.
She set out to see if horse-skin thickness and nerves were really that different to human skin.
She took a piece of horse skin from the flank area, as well as a piece of skin from the equivalent area on a human. She examined both the structure of the skin and the precise location and amount of nerve tissue.
Her work under a microscope revealed that horse skin was less than 1mm thicker than human skin, but that the horse epidermis was actually thinner than the human epidermis. She described both findings as surprising.
Tong then employed a special stain that coloured only nerve tissue, revealing that horses appeared to have considerably more nerve endings in their skin than humans, including the nerves in the epidermis where the pain sensation primarily occurs.
“We were astounded by these simple findings,” Tong said.
She said she intended to extend her work into a full-sized research project.
“I believe that the best way to make a decision about horse whipping is by establishing the facts through science.
“Are we using pain to make horses run faster? So far, it certainly looks like it.”
Australian Racing Board chief executive Peter McGauran told Catalyst that the industry was satisfied, on all the available veterinary advice that, if jockeys kept to the limit of strikes allowed under the rules, there was no cruelty to a horse.
The whip used in horse-racing was padded, he noted.
“There are strict rules as to how often a jockey can strike a horse and in what manner. And I believe this does not inflict pain on a horse.
“It’s instead part of the urging of a horse to extract the best possible performance. If there was any aspect of cruelty to it, neither I nor the many thousands of people who care tenderly and lovingly for these horses would have a part of it.”
He acknowledged that if evidence emerged that it inflicted pain, then the industry would do away with the whip.