The effect of probiotic bacteria in culture media using organic fertilizer for population density, biomass production and nutrient quality of Phronima sp. as natural feed

Phronima sp. is a natural feed with high nutrient content, and it can be an alternative substitute for Artemia. The existence of probiotic bacteria in culture media aims to improve water quality through biodegradation, maintain microbial balance and control pathogenic bacteria, so that nutrients in culture media can be utilized by Phronima sp. This study aimed to determine the effect of fermented organic fertilizer by probiotic bacteria in mass culture media on the population density, biomass production and nutrient content of Phronima sp. and to find the best culture media composition for mass culture of Phronima sp. The study was conducted with a completely randomized design with five treatments and three replications. The treatments were as follows: A: 0% chicken manure, 50% rice bran, 50% tofu waste; B: 25% chicken manure, 37.5% rice bran, 37.5% tofu waste; C: 50% chicken manure, 25% rice bran, 25% tofu waste; D: 75% chicken manure, 12.5% rice bran, 12.5% tofu waste and E: 100% chicken manure. The test animals were Phronima sp., and during cultivation, fertilization was carried out every 3 days. Population density and biomass were observed, and proximate analysis, amino acid profile analysis and fatty acid profile analysis were performed. The highest population density was at treatment B, with a peak population of 98 individuals/L that occurred on the 16th day of maintenance culture, and the highest biomass of 0.51 g was at the same treatment. The highest nutrient content was obtained at treatment B, for which the highest protein proximate analysis value was 58.90%, the proportion of the fatty acids comprised of eicosapentaenoic acid was 7.53%, and lysine amino acids were found at 44.16 ppm.