Probiotic yeast enhanced growth performance and disease resistance in freshwater catfish gulsa tengra, Mystus cavasius

Abstract

This study was carried out to evaluate the effects of commercially available baker’s yeast as feed additive on growth performance, feed utilization and disease resistance in freshwater catfish Mystus cavasius. Fish fry (0.5 ± 0.2 g) were randomly distributed into twelve glass aquaria (65 L) at a stocking density of 15 fish per aquarium. Fish were fed an experimental diet containing 0 (control, T1), 0.5 (T2), 1.0 (T3), 1.5 (T4) g yeast/kg diet for 75 days. After this period, fish of each treatment were challenged against fish pathogenic bacteria Pseudomonas fluorescens and the mortality rate was recorded for a week. Growth parameters (survival rate, weight gain, specific growth rate, and protein efficiency ratio) were significantly (P < 0.05) increased in fish treated with experimental diets T2, T3 and T4 compared to control T1. Weight gain (436.36%), condition factor (1.92 ± 0.03), specific growth rate (2.23 ± 0.04), and protein efficiency ratio (0.48 ± 0.05) were significantly highest in T3 than other treatments. The feed conversion ratio was significantly decreased in T3 treatment (P < 0.05). The lowest fish mortality rate (10%) was observed in the challenged fish of T3 treatment which was fed with 1.0 g yeast/kg diet. The results indicated that yeast supplement is a promising growth promoter and might be an alternative method to antibiotics for disease prevention of M. cavasius. Keywords: Gulsa tengra (Mystuscavasius), Probiotic, Yeast (Saccharomyces cerevisiae), Growth performance, Disease resistance