No abstract

Rietje J.M. Bokau*), Dian Febriani, Nur Indariyanti, and Rakhmawati. 2018. DOSAGE Optimization Of Artificial Digestive Enzymes In Feed To Improve The Digestibility And Growth Of Osphronemus gourami. Aquacultura Indonesiana, 19(2): 83-89. One of the obstacles often encountered in the cultivation of gourami is a relatively slow rate of growth compared with other freshwater fishes. This slow growth is partly due to the incomplete and unbalanced nutritional content and the low ability of the fish to digest a certain type of feed materials. The ability to digest fish feed types depends on the quality and quantity of feed and enzymes present in the digestive tract. The enzymes released by the glands in the gut have the function to digest food elements. Among the enzymes involved in digestion are amylase, protease, lipase, cellulase, pectinase, and pullulanase. To improve digestion, the use of artificial enzymes in certain doses is combined with natural food such as papaya to optimize the dose of artificial enzymes. The use of papaya is already widely used as a food supplement, especially in the gourami grow-out culture. Aside from being natural food, papaya leaves can also serve as a natural source of digestive enzymes. The objective of this study was to determine the optimal dose of artificial enzymes added to feed which can improve the digestibility and growth of gourami. In this study, treatments of artificial feeding of gourami were used addition of artificial enzymes amounting to 1% (A), 2% (B), 3% (C), papaya leaves and pellets (D), and pellets alone (E). Results after two months rearing showed that the digestibility of feed supplemented with natural enzymes in papaya (papain) can be further improve optimized by the addition of artificial digestive enzymes in a dose of 3% of the weight of the feed, the fish of this treatments group showed that faster growth compared with other treatments.

The objective of this research was to study the effect of replacement of fish meal with maggot meal for growth and survival rate and to determine the best percentage of substitution maggot meal in the diets of nile tilapia (Oreochromis niloticus) growing. Maggot used was the result of mass culture through the rearing of Black Soldier Fly (BSF) in the cage to produce eggs. Furthermore, the eggs harvested and spread on the medium of palm kernel cake for bioconversion process for 10 days and harvested, dried and milled. Replacement of fish meal with maggot meal in diets as a treatment was A (0%), B (10%), C (20%), D (30%), and E (40%) with a feed protein content 30%. The total of 350 nile as test fish with an average weigth 10-12g were cultivated in 15 units of aquarium 60 l and nurtured for 49days. The experimental method used was a completly randomized design and were analyzed by ANOVA and multiple comparisons. Among treatment means were made with Duncan's multiple comparison test using the Statistical Analysis Software Program of SPSS version 21 for Windows. all probability values were considered statistically significant at the level of P< 0.05. The result of this study show that replacement fish meal with maggot meal at various percentages of dietary treatments have a significant effect on growth, survival rate, and FCR, nevertheless the most optimal percentage is at 30%.