We, humans, are known as social animals, who can suffer mentally and are prone to stress in isolation. As we have seen in the COVID-19 pandemic.
New research on the horse immune system shows that horses also feel stressed when they are alone or have no company of their own.
The study suggests that horses need more freedom and friends than they often get. The horses housed in individual stables are more likely stressed as compared to those in a group.
A German study published in PLOS ONE compared the psychology of horses those who are kept alone causes stress-related immunomodulation compared to those who are in a group
A total of 15 two and three years old German Warmblood castrated male horses were raised and housed in a 3.2 x 3.5-meter area. They have limited contact with their neighbor’s horses through barred windows. Water and hay were provided and the horses received grain three times a day. Only 30 minutes per day of free movement of horses was enabled.
After a period of eight days, blood samples were collected from the stabled horses. Blood tests result showed signs of a stressed immune system. A persistent increase in the ratio of neutrophils-to-lymphocytes (types of white blood cells) was seen, but not in horses who are in a group.
“The result of the new study shows that social isolation is a chronic stressor and can cause negative impacts on horses” Sonja Schmucker from the University of Hohenheim and one of the report’s authors.
“It can decrease immunocompetence and might increase disease exposure of the horses and will have a negative impact on their health and welfare”.
Mixed Response to Study
Not everyone is convinced by the author’s claim that due to isolation causes stress as seen in the new study. however.
Australian veterinarian of the University of New England, Paul McGreevy, who was not involved in this study said, “Horses are social animals and do not evolve to be isolated from each other”.
“Horses’ heart rates became lower when they groomed together. If they spend time together and mutually groom, they thrive” said McGreevy.
McGreevy said that the previous study was about the behavioral changes in boxed horses, but the new study is the first of its kind.
Another veterinary scientist Susan Hazel of the University of Adelaide that the study was well taken using “Validated Measures”.
However, she said that the findings of the study need to be confirmed. She said that the study measured horses over eight days, and it is not possible to conclude the effects on the immune system were long-lasting.
Veterinary scientist Charles El-Hage at the University of Melbourne agreed that horses are social animals and can change behaviors due to isolation. But he said that the effects seen in the study measure could also be due to different diets, or due to allergens in the environment.
Horses need ‘Foraging, Freedom and Friendy ‘
Dr. Kirrilly Thompson at the University of Newcastle, who studies the interaction between humans and horses as a cultural anthropologist, argued as said the horses need to be in the group.
“Individual Stabling is Stressful for Horses” ~ Dr Kirrilly
Horses are designed to walk and graze with their head down most of the time. They use their peripheral vision to keep an eye on the others in their group, Thompson said.
“If a horse is grazing and sees another horse with head up or tense, then that horse will also put his head up. They will put their heads up and will run off”.