EFFECTS OF VARYING DIETARY PROTEIN LEVELS ON DEVELOPMENT OF GONADS AND NUTRIENT RESERVES OF TANK RAISED Tilapia rendalli (BOULENGER, 1896)
RODGERS MAKWINJA *
Department of Fisheries Science, Mzuzu University, P/Bag 201, Luwinga, Mzuzu 2, Malawi.
FANUEL KAPUTE
Department of Fisheries Science, Mzuzu University, P/Bag 201, Luwinga, Mzuzu 2, Malawi.
WALES SINGINI
Department of Fisheries Science, Mzuzu University, P/Bag 201, Luwinga, Mzuzu 2, Malawi.
HASTINGS ZIDANA
Department of Fisheries, National Aquaculture Centre, P.O.Box 44, Domasi, Zomba, Malawi.
*Author to whom correspondence should be addressed.
Abstract
This study was carried out to investigate the effects of varying dietary protein levels in feed on reproductive performance of Tilapia rendalli. One hundred and eighty (180) Tilapia rendalli fingerlings with an average body weight of 9.8±0.02 g were stocked into 12 experimental concrete tanks at 15fish per 3m3. The fish were subjected to four level crude protein (CP) diets - 30%, 35%, 40% and 45% for 90 days. High nutrition reserves was realised in the fish fed on 40% CP compared to those fed on 30%, 35% and 45% CP diets. Conversely, dietary protein level within the range of 30 to 45% did not significantly affect gonadosomatic index. The study recommends that Tilapia rendalli should be fed on a diet containing 40% protein level to achieve high reproductive performance.
Keywords: Gonadosomatic index, hepatosomatic index, dietary protein, Tilapia rendalli