Vitamin A requirements of Heterobranchus longifilis fingerlings
2012
Ibiyo, L.M.O. | OjO, D.H.
The growth response of Heterobranchus longifilis fingerlings (0.86~c0.07g) to supplementation of graded levels of vitamin A (0, 500, 1000, 1500 or 2000 mg/kg; Bio-Organics Nutrient System Limited, Lagos) into a 42.5% crude protein basal diet was investigated. Completely randomized design with triplicates was used in a mini flow through system after 2 weeks acclimatization for 20 weeks in New Bussa, Niger State, Nigeria. There was significant difference (P>0.05) in feed intake, weight gain and survival between fish fed control diet (Omg vitamin A kg-1 diet) and the supplemented groups. The significantly (P<0. 05) poorest feed conversion ratio, protein conversion ratio and specific growth rate were recorded in the group fed 2000 mg vitamin A kg-1 diet. However, whole body vitamin A concentration was significantly (P<0.05) higher in the supplemented groups than the control but no significant different (P>0.05) between supplemented groups. It was concluded that a diet containing adequate amount of macro and micro-nutrients with good lipid source will be able to provide vitamin A that can favour good growth in H. longifilis fingerlings. There is need to determine the response of the fish to vitamin A supplementation in an outdoor environment as vitamin A is required for the regeneration of light-sensitive compound rhodopsin.
显示更多 [+] 显示较少 [-]Includes: 3 tables and 1 figure;Also includes: 13 refs.
显示更多 [+] 显示较少 [-]