Abstract:
A 45- days randomized factorial design 3×2 (Three levels 25,50 and
75%) of palm date pits, three level (Non, with and without) of 3% bakery
yeast (Saccharomyces cerevisiae) and three replicates. The experiment was
conducted in twenty one plastic aquaria .The all-male Nile tilapia
(Orechromis niloticus) fingerlings were placed in each aquaria. Each
aquarium supplied with well-aerated and precipitated dechlorinated tap water
with an average weight 1.9±1.11 g/fish (10 fish/aquaria) and total length
5.18±0.69 cm/fish. Fish were fed three times/day (10 days, at 8.30-11.30 -
3.30 A.M) at a rate of 12, 8 and 4% of body weight, to study the Effect of
partial replacement of animal protein (fish meal) in the diet on growth
performance, carcass composition, feed utilization, condition factor(k) and
feed cost . Seven experimental diets were prepared; control diet (T0, CP
36.84) contained 45% (fish meal) as animal protein and 0% (palm date pit
meal) plant protein. Tested diets (T1, T2 and T3 ) contained 25, 50, 75% with
3% bakery yeast (CP 35.71, 35.53, 34.74) and 25,50,75% without
yeast(CP36.01, 36.27 and 35.57) respectively ; in order to substituting about
75, 50, and 25 of fish meal diet respectively. The results revealed that, tilapia
fed on T1 , T2 and T4 diets (25, 50 and 25%) replacement with and without
yeast respectively recorded the best growth performance, feed and protein
utilization than other experimental as compared to control diet, also they
represent the highest condition factor(K) values which indicate that the fish
are in good health. Tilapia fed on diet T3 (25%fish meal ) T5,T6 (50 and
25%fish meal) with and without yeast respectively had poor growth and
differ significantly (p<0.05) from the rest diets . Diet composition
significantly affect carcass composition. These data suggested that Palm date
Pit with and without yeast Saccharomyces cerevisiae can partially replacefish meal (animal protein) in fingerlings all-male Nile tilapia diet at level up
