اثرسطوح متفاوت جايگزيني پودر شفيره كرم ابريشم به جاي پودر ماهي در رشد، بقاء و تركيب بدن ماهي قزل آلاي رنگين كمان (Oncorhynchus mykiss)

Effects of fish meal replacement by silkworm pupae on growth, survival and body chemical composition of rainbow trout(Oncorhynchus my kiss)

Silkworm pupae meal is a non-conventional animal protein feedstuff. It is the by-product after the silk thread has been wound off from the cocoon. To investigate the effects of animal protein on growth and survival of rainbow trout {Oncorhynchus my kiss), a sixty-day feeding experiment was conducted. Four replacement levels (0, 5, 10 and 15 percent) of silkworm pupae meal were compared using a completely random design. We used 360 juvenile rainbow trout (average weight 55±3.42g) divided into 4 groups and 3 replications, each containing 30 trout for 60 days. Sampling for nutritional effects was carried out every 10 days and at the end of the experiment, weight gain, feed conversion ratio, specific growth rate, protein and efficiency ratio were compared which showed no significant differences (P>0.05) among the treatments. Total length and survival rate were not significantly affected in the treatment groups. The highest percentage of carcass protein and the lowest percentage of carcass fat belonged to the control treatment. Our findings showed that silkworm pupae meal could replace 15% of fish meal diet in rainbow trout culture.