EFFECT OF THE FEMALE REPRODUCTIVE TRACT ON SPERM METABOLISM IN THE RABBIT AND FOWL

Abstract

Summary. A fourfold increase in oxygen uptake by rabbit spermatozoa incubated in the rabbit uterus and a twofold increase in cock spermatozoa incubated in the hen's oviduct over ejaculated spermatozoa is the first reproducible biochemical change to be demonstrated in spermatozoa residing in the female genital tract. It was shown that these rapidly respiring spermatozoa were capacitated because they fertilized 18% of the eggs tested as compared to no eggs fertilized by freshly ejaculated spermatozoa. It was found that oviduct fluid in vitro stimulates respiration fivefold in spermatozoa protected from light. Increase in oxygen consumption by spermatozoa residing in the female reproductive tract may be an important part of the capacitation process.