The effect of protein levels in fermentation feed supplemented lumbricus sp. extract as feed additive on growth performance and body chemical composition of milkfish, Chanos chanos forskal 1775

Abstract

Abstract Protein is the main nutrient in feed and is sourced from relatively expensive feed ingredients, so it is necessary to optimize use by providing feed additives. This study aims to determine the levels protein of fermented feed supplemented Lumbricus sp. extracts as a feed additive that provides the best response to milkfish growth performance and body chemical composition. Milkfish with an initial weight of 8.52±0.29 g head-1 maintained a density of 30 fish per hapa measuring 1 m3 of 24 units. Hapa installed in ponds with a water height of ±60 cm. The study was designed in a completely randomized design with the treatment of various levels of feed protein, namely 20, 25, 30, and 35%. Before printing into pellets, the feed material is fermented with microorganisms mix for seven days and supplemented with 300 mL kg-1 of feed ingredients Lumbricus sp. extracts. During 50 days of rearing fed 5% given of body weight per day three times a day morning, afternoon and evening. The results showed various levels of feed protein gave the same results on milkfish growth performance and body chemical composition. The resulting relative weight growth ranged from 58.47±2.11-60.46±0.40%, survival rate 88.89±3.85-94.44±5.09%, feed efficiency 40.44±1.98-43.06±1.27%, body chemical composition (including protein content 67.52±0.52-68.59±0.67%, fat 13.77±0.56 13.84±0.22%, fiber 1.59±0.03-1.66±0.13%, nitrogen-free extract 2.19±0.33-2.57±0.24%, and ash 13.41±0.44-14.60±1.61%), body energy levels 3545.31±31.24-3585.61±14.94 cal kg-1, liver glycogen 5.16±0.71-6.34±0.11-6.34±0.11 mg g-1 and muscle 4.46±0.30-5.11±0.10 mg g-1, and hepatosomatic index 2.28±0.07-2.32±0.11. Thus, 20% protein content in fermented feed supplemented with Lumbricus sp. extracts is enough to meet the needs of milkfish.