GROWTH RESPONSE, NUTRIENT UTILIZATION AND SURVIVAL OF NILE TILAPIA (Oreochromis niloticus) FED VARYING LEVELS OF CHAYA LEAF (Cnidoscolus Chayamansa) MEAL

Abstract

A feeding trial was designed and carried out to assess the growth response, nutrient utilization and survival of Oreochromis niloticus fed graded levels of Chaya leaf meal based diets. Two hundred and seventy (270) fingerlings of O. niloticus of average weight of 3.75 ± 0.14g were fed with six  iso-nitrogenous diets containing 35% crude protein. The Chaya leaf meal (CLM) protein replaced     soybean meal in the diets in the following proportions: Diet 1 (0% CLM), Diet II (20%CLM), Diet III (40% CLM), Diet IV (60% CLM), Diet V (80% CLM) and Diet VI (100%CLM). At the end of the trial, the mean weight gain of fish was highest in diet 1 with a value of 5.07g and lowest in diet VI with a value of 3.29g. There was no significant difference (P>0.05) in the mean weight gain (MWG) of fish fed diet 1 and fish fed diet II. Feed conversion ratio (FCR) was best in fish fed diet II (2.44) but not significantly different (P>0.05) from fish fed diet I (2.50). The highest specific growth rate (SGR) of 0.66%/day in fish fed diet I was significantly higher (P<0.05) than others except fish fed diet II with a value of 0.61%/day.  The  highest protein efficiency ratio (PER) was obtained for fish fed diet I with a value 0.98 while the lowest value was obtained for fish in diet VI with a value of 0.74. There was no significant difference (P>0.05) in MWG, FCR, SGR and PER between fish fed diet I and II. The highest net protein utilization (NPU) recorded was also significantly higher (P<0.05) in diet I which was 51.40% while the lowest value of 13.13% was recorded in diet VI which was  13.13%. Percentage survival was highest (100%) in fish fed diets V and VI, while fish fed diets I and II recorded 90% each. It was however observed that chaya leaf meal protein can favourably replace 20% of soybean meal protein in the diets of Nile tilapia, O. niloticus.