The present study is designed to evaluate the impact of potential probiotics Enterococcus faecium QAUEF01 in single and its mix-culture with Geotrichum candidum QAUGC01 on the Labeo rohita (Hamilton, 1822). In the mix-culture, both bacteria and yeast survived comparatively better under mimic gut conditions and showed higher hydrophobicity. Moreover, mix-culture showed comparatively more antipathogenic activity. A feeding trial of 90 days for L. rohita fingerlings comprising of three treatments, control group fed on basal diet, second group fed on E. faecium supplemented diet and third group was fed on mix-culture probiotics supplemented diet. Mix-culture probiotics fed group showed significantly higher (P<0.05) growth as compared to control. Better specific growth rate (SGR) was significantly correlated with the feed conversion ratio (FCR) and feed conversion efficiency (FCE), protease and cellulase activity in probiotic fed fishes. The applied probiotics established well in fish gut and shown no harmful impact on fish physiology. Probiotic application distinctly modulated fish gut microbiome evident by increased level of friendly microbiota and exclusion of potential fish pathogens. The results suggested an effective eco-friendly strategy to boost the fish productivity.

Assessment of current scenario related to food quality and safety determine that pathogenic microflora have gained resistance towards microbial agents through DNA vertical and horizontal transmission as a result of continual utilization of beneficial microflora [1]. As a result, these pathogenic microflora causes spoilage of food or make them unable for consumption. To resolve this reckless issue, scientists from all over the world are engaged to discover microorganisms (probiotics) proved to be beneficial to feed living organisms.