Hormones and Stallion Reproduction
There is less chance to use hormones to manipulate stallion reproduction. Use of exogenous lights will cause and earlier increase in sperm production (lights on Dec 1 gives increased sperm production Feb 1). It is unclear if levels of sperm production can be maintained since some studies show a decrease in sperm production by May 1 if Dec 1 lights are used. The number of breedings per week after May 1 may need to be decreased if high fertility is desired. Since lighting in barns must be changed for mares, it is often changed for stallions at the same time. This does assure maximal sperm production with the increased lights from February - April.
