Index of Proteolytic Bacterial Activity in Rice-Fish Farming System

Abstract

Rice-fish farming system cultivation is one of the developments in fisheries cultivation technology that can increase the economic value of society. However, fish farming activities carried out in rice-fish farming system ponds will produce organic waste from metabolic waste and inedible feed. The organic waste in the water is used to grow and reproduce bacteria. This study aimed to determine the number of bacteria and the proteolytic bacterial activity index in the water of rice cultivation ponds. Purposive sampling method was employed in the study, namely by taking water samples in each rice-fish farming system cultivation pond at predetermined points and representing the population. Bacterial isolation was conducted on general bacterial media and skim milk agar media. Then Gram, catalase, and oxidase tests were conducted and the proteolytic activity index was calculated. The results obtained from this study were bacterial counts ranging from 0.18-0.8 x 10⁴ CFU/mL. Pond A's proteolytic bacterial activity index at the inlet point was 0.22, the middle was 1, and the outlet was 0.54. The results of the proteolytic activity index for the Pond E at the inlet point was 0.84, middle, and it was 1.2, and outlet 0.84. Apart from that, the average proteolytic activity index, in Pond A it was 0.5, and in Pond E the average proteolytic activity index was 0.9.