Last Updated on February 23, 2022 by Allison Price
Q: My gelding leads our herd and takes his job very seriously. He is always looking for his sisters, and gets anxious when they are separated. He is a distraction because he wants to know where his girls are. Although I have dealt with buddy-sour and barn horses before, this one is just so energetic and full of spirit that I don’t know if anything is working. I am open for suggestions and reassurance that it is a slow, long road.
Cristy WhatellPittsboro (North Carolina
A: This behavior is not uncommon for horses. This behavior is common in geldings. It is not dominance, but male sexual behavior. He could also be dominant, which is when he demands first access to resources like food or salt licks. Males tend to be dominant over mares. The problem is that he’s assumed the role as stallion within his group.Even after losing their testosterone supply, many geldings behave like stallions.
Castration of a horse results in the removal of his testicles, which are the source for testosterone. One of the most significant effects of testosterone is felt long before the colt’s castration. This is because the colt is still in utero. The mare’s hormones stimulate the foetus’s gonads, so his testes produce a lot male hormones called androgens. These androgens work on the brain to make it masculine. The brain of a male is very different to that of a woman. It has a more sexually dimorphic nucleus. Many geldings behave as stallions even though they have less testosterone.
It is possible that your horse wasn’t fully gelded. A horse that is a cryptorchid means one of his testes failed to fall into the scrotum will continue to secrete testosterone. Two blood samples are taken to identify cryptorchids. The first is to determine the horse’s testosterone level at rest. The second is taken after the horse has received an injection of human-chorionic gonadotropin. This will stimulate any remaining testicular tissue to produce testosterone and estrogen. If the hormone levels in the second sample are high, your horse is likely to be a cryptorchid. A surgeon would need to examine the abdomen for any remaining testicles.
It is likely that you are more interested in the solution than in the cause of this problem. Although training can help horses like this, it is difficult to change his biology. Management is the best way to avoid this problem. Don’t pasture geldings alongside mares. This might not be possible at smaller farms. Your veterinarian may prescribe medication to help reduce anxiety if you are unable to separate your horses from their mares. Cyproheptadine, an anti-androgen drug, might be able to help.
I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!