Line breeding
I’ve added some pedigree information regarding the coefficient of line breeding (google it ) basically it’s just a calculated percentage of how line bred your horse is.
Line breeding has always been a been a part of raising horses but as we’ve become so specialized, finding out crosses that are compatible is looking more and more difficult.
Other species, dogs in particular have issues with small litters, fertility problems, soundness and not to mention a terrible pr problem and horses seem to be not far behind.
I’m nut shelling here. But
with dogs lots of studies show that problems begin when coefficients get above 5%, some studies were done on thoroughbreds showing similar results with fewer Grade 1 stakes winners with coefficients above 5%. However they did note that with horses the performance wouldn’t likely be as affected as much as fertility, soundness and size.
Which makes me wonder if that’s why it’s so much more difficult to get mares to carry a foal now as opposed to 30 yrs ago. Not to mention 14-1 HH is far more common in the performance horse industry than 15 HH