INDUCTION OF SPERMIATION AND OVULATION IN THE LOCAL TOAD, BUFO MELANOSTICTUS SCHNEIDER

Abstract

The effects of different dosages of toad pituitaries, human chorionic gonadotrophin (HCG), pregnant mare serum (PMS) and a combination of serum and chorionic gonado- trophins on the abundance of sperm released, the time of spermiation and the duration of spermiation were studied in the common toad, Bufo melanostictus. The relation between dosage of hormone and abundance of sperm released was difficult to qualify. The time of spermiation was found to decrease with increase in dosage of hormone. A longer duration of sperm. released was generally obtained with higher dosage. Among the hormones used, the homologous pituitary was still a better inducer of spermiation. HCG appeared to be more effective than PMS. Ovulation was success- fully induced in B. melanostictus with its own pituitary hormones. The effect was enhanced by 17 K - hydroxyproges- terone but the injection of 17 « - hydroxyprogesterone alone did not induce any ovulation. However, oviducal jelly secretion could be provoked by 17 « - hydroxypro- gesterone.