Effect of Lysine and Poultry Slaughterhouse by Product Meal on Growth Performance, Feed Efficiency, and Blood Profile of Sangkuriang Catfish (Clarias gariepinus var. Sangkuriang)

The increasing demand for livestock and poultry feeds results in the lack of fish meals (FM). Poultry slaughterhouse by-product (PSB) is one promising strategy due to its high protein content despite the limited content of lysine. Thus, supplementing lysine in dietary fish feed is necessary. The present study aimed to investigate how different lysine doses in feed with PSB and FM as animal protein sources affected protein digestibility, feed utilization, growth, hematology, and body composition of Sangkuriang catfish (Clarias gariepinus var. Sangkuriang). Sangkuriang catfish at the grow-out stage (15.54±0.17 g/fish) were used. The fish were fed six experimental diets with similar protein and energy content but different lysine levels at 1.25%, 1.75%, 2.25%, 2.75%, 3.25%, and 3.75%/kg (treatments 1 to 6). The addition of lysine to feed had a significant (P<0.05) effect on protein digestibility (ADCp), efficiency of feed utilization (EFU), and relative growth rate (RGR) of Sangkuriang catfish at a grow-out stage but had no significant (P>0.05) effect on survival rate, hematology, and nutrient content. The optimal doses of dietary lysine with PSB and FM to improve ADCp, EFU, and RGR of Sangkuriang catfish were 2.59%, 2.63%, and 2.62%/kg diet, respectively. However, the supplementation of PSB in experimental diets had no significant effect on glucose, triglyceride, total protein, urea, calcium, magnesium, albumin, globulin, hemoglobin, hematocrit, phosphorous, and mean corpuscular hemoglobin concentration (MCHC). The lysine addition in feed formulated with PSB and FM could improve the growth performance and increase the feed digestibility of Sangkuriang catfish at the grow-out stage.