Can horse owners tell when their horse is stressed? If the animal is in pain? And can they tell the difference between the two?
Recently, thanks to FitoCavallo® pain infographics, the use of facial expressions in horses, especially for the purpose of pain detection, has been gaining ground in our country. But what about stress?
It is a very subjective thing to "feel", to intuitively sense when a horse is unhappy, uncomfortable, stressed or in pain. No doubt many riders intuitively sense this, but judging from photos of Facebook and Instagram posts, it seems that even more riders are 'not getting it'. The proud, smiling faces of the riders and the stressed or pained grimaces of the horse underneath them reflect contradictory states and make for a very disharmonious picture.
Whether the horse is ridden by a novice or an advanced rider, care should be taken to ensure that the animal is not caused pain and/or increased stress by the human's amusement. Novice riders should preferably be given a level of exercise appropriate to their ability. For example, riders who are not yet able to ride with a calm, sensitive hand, or to give the horse clear and comprehensible instructions, should not be sent to a 'harmless' home competition where they are asked to ride a skill level that exceeds their own. When photos of such events pop up on Facebook, no one should be surprised if some riders are critical of the pictures, the knowledge of the riders and the competence and attitude of the trainers.
Before criticising our fellow riders, we have to recognise that it can be difficult as a novice to know what it is like to see a horse make an "unhappy face". However, it is a rightly expected knowledge from trainers, equine professionals and veterinarians. Being able to objectively recognise how a horse is feeling can make a significant difference to the way riders, trainers and carers deal with animals and the problems they face.
Lundblad* and his fellow researchers decided to study the facial expressions of horses when the animals are under stress. They used a standard coding program - EquiFACS - to record the signals. EquiFACS records not just the facial activity that scientists think they should be looking for, but all the signals.
(*: Johan Lundblad, PhD candidate at the Department of Anatomy, Life Sciences and Biochemistry, Swedish University of Agricultural Sciences, Uppsala).
Because stress and pain show very similar facial expressions in humans and other animals, scientists studying horses fear that such grimaces may be difficult to decipher in horses.
To carry out the study, the researchers put the horses on horse carriages and locked them in stalls, one by one, separated from their peers. During these two stressful situations, they watched the horses' facial expressions, looking for signs of stress - as these situations apparently did not cause pain in the already healthy horses.
In the stressful situations, the following were observed on the animals' faces:
increased visibility of eye proteins
elevation of the inner eyebrows
lifting of the upper lip
tongue extension (licking of lips)