A COMPARISON OF 2 SPAWNING-INDUCING AGENTS FOR COMMON CARP

Two spawning-inducing agents, Dagin and calibrated carp pituitary extr act (CPE), were compared under routine hatchery conditions in Israel d uring the 1994 breeding season. Comparison was made of three parameter s: (a) variance of latency, i.e. the variation in the period between h ormone administration and ovulation; (b) spawning ratio, i.e. the numb er of females which ovulated after injection divided by the total numb er of injected females and (c) embryo viability, i.e. the number of vi able embryos divided by the total number of eggs (x 100%). Results sho wed that variance of latency is greater when Dagin is administered. Th e spawning ratios of the two agents did not differ. Also, there were n o significant differences in embryo viability although it was higher a fter administration of CPE.