The Effects of Dietary Levels of Protein and Greenhouse on Growth, Behaviour and Fecundity of Nile tilapia (Oreochromis niloticus L.) Broodstock

The aim of the study was to assess the main and interactive effects of greenhouse and dietary crude protein levels on growth, behavior and fecundity of Nile tilapia at Kegati aquaculture research station, Kisii, Kenya from July to August, 2012. Mixed sex tilapia broodtock (251.761.57g) were distributed at random among 12 hapa (1m3), 6 under greenhouse and 6 in open pond, 6 fish in each hapa at the ratio of 1male: 2 females. With the exception of temperature, there was no significant (p greater than 0.05) variation in water quality parameters between greenhouse and open pond. Greenhouse was able to raise water temperature with an average of 7.82 0C above the open pond conditions. Dietary crude protein level and greenhouse had a strong interactive effect on WG ( %), SGR, fecundity and spawning frequency of tilapia broodstock. The current study suggests that the recommended maximum level of dietary crude protein level to maintain the welfare and performance of Nile tilapia broodstock is between 25-30 % with a maximum advantage of greenhouse culture