Effect of various levels of egg yolk, milk, seminal plasma or blood serum on the respiration and reproductive efficiency of chicken spermatozoa.

Washed chicken spermatozoa were suspended in a phosphate buffer containing various concentrations of egg yolk, milk, seminal plasma or blood serum; sperm respiration, fertility and hatchability were measured. Concentrations of 4, 8, 16 and 32% chicken or turkey egg yolk decreased the respiration rate of spermatozoa after 120 min. of incubation at 41 degrees C., while pasteurized milk at similar concentrations stimulated oxygen uptake. Also, concentrations of 16% raw milk, 32% seminal plasma and 32% preovulation blood serum increased respiration rates. In general, fertility was not affected by most concentrations of seminal plasma, milk or turkey egg yolk. However, as the concentration of chicken egg yolk increased fertility decreased. All levels of blood serum significantly reduced the fertilizing capacity when compared to the 0% level. Hatchability was not affected by any of the additives tested.