Evaluasi Penambahan Ragi Limbah Produksi Bir dalam Pakan terhadap Kinerja Pertumbuhan dan Daya Tahan Ikan Lele Clarias sp. akibat Infeksi Aeromonas hydrophila

Abstract

The purpose of the study was to test on field-scale the addition of brewer’s yeast Saccharomyces cerevisiae which was considered as brewery by-product in feed on growth performance and immunity of catfish against the infection of Aeromonas hydrophila. Catfish weighed 2.09 ± 0.01 g with average length of 6.42 ± 0.07 cm were stocked in tarpaulin ponds 200 x 200 x 80 cm3 as much as 1.000 fish/pond with 2 treatments and 3 replications. Fish were fed commercial feed without brewer’s yeast addition (K), and brewer’s yeast added feed (RB) for 30 days and the growth response were observed. Fish were challenged in aquariums 60 x 30 x 25 cm3 using 3 treatments and 3 replications which consisted of K- (PBS injected fish), K+ (A. hydrophila injected fish), and RB (A. hydrophila injected fish). After injection, fish were fed K feed for 10 days and the mortality rate were observed. The results showed that feeding with RB feed increased the growth rate of the fish and decreased the feed conversion ratio. Cost analysis showed that RB treatment could decrease feed production cost toRp 33917 from Rp 39418 (control). Fish immunity were increased with increasing total blood leukocytes, suppressed A. hydrophila infection indicated by lighter clinical symptoms showed, and suppressed mortality rate (71.67%) compared to K+ (95.00%).