Reproduction in rats and mice isoimmunized with homogenates of ovary or testis with epididymis, or sperm suspensions

Female rats and mice were injected with homologous spermatozoa without adjuvant, or with homogenates of ovary or testis+ epididymis in adjuvant. Ovulation was not inhibited and the numbers of eggs released were normal. Fertilization rates were significantly reduced in the mouse by all tissues injected and in the rat by injection of ovarian homogenate only. Fracture of and a weak precipitate on the zona pellucida of the eggs were observed in the mouse but not in the rat after injection of ovarian homogenates. The number of pregnancies and litter sizes were reduced following the first and second mating after treatment in the mouse but not in the rat. When eggs with or without follicular cells were examined in vitro, fertilizability was very low if the donor had been treated with ovarian homogenate, better with testis+epididymis homogenate and best after treatment with sperm suspension. Failure of fertilization appeared to be the major cause of infertility after such treatments.