Growth Response of Heterobranchus Longifilis Fingerlings Fed Diets Supplemented with Moringa Oleifera Leaf Meal as Replacement of Soybean Meal

Moringa leaf meal (MLM) is a source of protein from a highly valued plant Moringa oleifera. Its protein has a profile of amino acids similar to that of soybean. A completely randomized design with three replicates was used in a 42 days study to determine digestibility and growth performance of 150 Heterobranchus longifilis fingerlings. Graded levels (0, 5, 10, 15 or 20) % of dried MLM was used to replace soybean meal in a 42.5% crude protein H. longifilis diet fed at 5% in the first 2 weeks and subsequently 3% body weight. The results showed that there were significant differences in weight gain (WG) and specific growth rate (SGR) of the fish with the significant highest observed in the group that fed on diet 2 with 5% MLM supplementation (P<0.05) though not significantly different from the control (P>0.05). The significant poorest WG and SGR were obtained in the group that fed on diet with 20% level of MLM supplementation (P<0.05). There was no significant difference between treatments in terms of initial weight, feed intake and survival (P>0.05). However there were significant differences in feed conversion ratio (FCR), SGR, total length and standard length among the groups that fed on diets with 15% and 20% supplementations (P<0.05). The haematocrit and hemoglobin were also significantly reduced in the group that fed on the highest level of supplementation (P<0.05). The in-vitro trial revealed significant reduction in digestibility with increase in MLM supplementation level (P<0.05) the tannin and phytic-acid levels following the same trend. However there was no pathological defect observed in the fish from all the groups. There was no significant difference in the hepathosomatic index. The feed cost analysis showed a reduction in cost per 100kg feed with increased level of supplementation with 0.00, 11.50, 23.20, 34.00 and 50.64% for diets 1, 2, 3, 4 and 5 respectively. It was concluded that 5 – 10% MLM supplementation could be used in the diets of H. longifilis to obtain a reduction in cost of feeding it at 11.2% and 23.5% per 100Kg feed respectively. There is need to try other processing methods if the level could increase above that obtained from this study.

Keywords: Heterobranchus longifilis; Moringa leaf meal; Soybean meal; Digestibility and performance