Evaluation of kombucha tea as a feed additive for improving the protein and lipid retention of African catfish (Clarias gariepinus)

Kombucha tea is the product of sugared tea fermentation by a symbiotic culture of bacteria and yeast. This beverage contains a high source of the microbial community, such as acetic acid bacteria, lactic acid bacteria, and yeast, which may serve as an alternate source of probiotics. The present study aimed to investigate the effect of dietary enriched kombucha tea at different levels on the protein and lipid retention of African catfish (Clarias gariepinus). A total of 400 fish, with an average initial weight of 5.26±0.11 g, were randomly divided into five treatments. The diet treatment containing different volumes of added kombucha tea (4 mL, 6 mL, 8 mL, and 10 mL per kg of feed) was given and compared to the control, without kombucha addition. The fed was given at satiation three times a day for 30 days. The result showed a significant increase (P<0.05) in protein and lipid retention in the groups that received kombucha tea addition, compared to the control group. Kombucha tea addition at 8 mL/kg of feed resulted in the highest protein and lipid retention, but the addition above this value showed a slight decrease in protein and lipid retention. Overall, the present study proved that the addition of kombucha at the optimum levels in diet could improve the protein and lipid retention of fish, which are related to the fish's somatic growth. These results provide evidence of the potential application of kombucha tea in the aquaculture industry as a feed additive, especially for probiotic sources.