Viability of catfish (Clarias macrocephalus, Gunther) eggs fertilized at varying post‐ovulation times

HCG-induced (dose: 2 iug−1 body weight) ovulated eggs of catfish (Clarias macrocephalus) remained viable for artificial fertilization up to 10 h post-ovulation without apparent significant loss in fertility. At 12 h post-ovulation viability decreased significantly, showing little or no hatching at 20 h. A limit of 10 h between ovulation and egg-stripping was suggested for this species at an ambient temperature of 26–31° C.