Hibiscus petals as sterility agent on Nile tilapia. – S. B. Ekanem, P. B. Oku, and F. S. Udoden
To determine if hibiscus petals can induce sterility in Nile tilapia and if the sterility so induced is reversible, matured Nile tilapia each 40g were treated for 30 days with a low dose (5.6g/kg/day) and high dose (11.2g/kg/day) of powdered hibiscus petals incorporated into their feed. Fish of similar sizes in the control experiment were fed with feed that did not contain hibiscus petals. Both the high and the low dose treatment induced irreversible sterility in male and female Nile tilapia. Fish in the control experiment spawned two weeks into the experiment and again in the fifth week but fish treated with hibiscus petals did not spawn after the treatment had been discontinued, not even when they were mated with untreated fish. High dose treatment caused a significant reduction in fish weight (P<0.05). The study showed that low dose of hibiscus petals, given through feed, could be used to control prolific breeding in Nile tilapia.