The question of whether Thoroughbred stallions are overused often arises due to reports of elite stallions covering up to 250 mares per season. However, focusing on the number of mating events (rather than just the number of mares) shows that the demands on stallions in managed programs are comparable to, if not lighter than, those on their wild counterparts. Additionally, it’s essential to address a common misconception: stallions cannot be forced to breed.
Are Stallions Forced to Breed?
Simply put, no. Breeding is a natural behavior, and a stallion cannot be coerced into mating if he does not want to. This is why covering numbers vary from stallion to stallion. Factors like temperament, libido, and physical condition play a significant role in how many mares a stallion can cover.
The Case of Extreme Choice
Take Extreme Choice, for example, a highly sought-after Australian stallion due to his incredible success rate. Despite the demand, however, his fertility issues mean he cannot physically handle a large book of mares. As a result his books are deliberately kept small, prioritising his health and maximising his effectiveness.
Care and Rest Are Essential
Breeding stallions are closely monitored by veterinarians and handlers to ensure they are physically and mentally capable of covering mares. If a stallion shows signs of stress, fatigue, or lack of interest, his workload is adjusted accordingly ensuring stallions only cover what they can safely handle. It is also important to note that stallions are often extremely valuable animals, and hence, their wellbeing is in the very best interest of those managing them.
Wild Stallions: Frequent Mating to Ensure Conception
In the wild, stallions manage harems of 2 to 12 mares (Ransom et al., Ecological Applications). During the breeding season, mares enter estrus 8–10 times, with each cycle lasting 4–7 days. To ensure conception, wild stallions often mate with a mare 2–3 times daily during her estrus.
This results in:
- 200–300 mating events annually, depending on harem size and estrous overlaps (McDonnell, The Equid Ethogram).
- Significant physical strain on mares, which endure repeated matings within each cycle.
Thoroughbred Stallions: Managed Breeding with an Aim for Efficiency
In Thoroughbred breeding programmes, the goal is to achieve conception with just one cover per mare per cycle, although not all mares conceive on the first attempt. Veterinary intervention helps minimise the need for repeated covers
Most stallions in Australia cover 30–50 mares per season, resulting in roughly 40–70 mating events annually (Thoroughbred Breeders Association). Only a handful of elite stallions, covering up to 250 mares, may reach 300+ mating events.
The Clear Comparison
| Wild Stallions | Thoroughbred Stallions |
|---|---|
| 2–12 mares per harem | Covers 30–50 mares on average |
| 10–20 matings per mare | Aim for 1 mating per mare |
| 200–300 matings/year | 30–70 (average), up to 300 (elite stallions) |
So in conclusion, wild stallions and elite Thoroughbred stallions can both engage in 300 mating events annually, but the approach is vastly different.
Managed programmes aim for efficiency, with the aim of one cover per mare, reducing repetitive strain on both stallions and mares.
Breeding programs also respect the natural limits of each stallion. Examples like Extreme Choice show that the industry prioritises stallion welfare, ensuring they only cover what they can physically manage.
Sources
- McDonnell, S.M. (2003). The Equid Ethogram: A Practical Field Guide to Horse Behavior. Eclipse Press.
- Ransom, J.I., et al. (2016). “Feral Horse Ecology and Management.” Ecological Applications.
- Thoroughbred Breeders Association. (2019). Australian Breeding Report. Retrieved from tbaus.com.
- Aurich, J.E., & Wulf, M. (2020). “Management and Nutrition in Breeding Stallions.” Animal Reproduction Science.
