Growth performance and feed utilization of keureling fish Tor tambra (Cyprinidae) fed formulated diet supplemented with enhanced probiotic.

Background: The objective of the present study was to determine the optimum dosage of probiotic in the diet of keureling fish ( Tor tambra ) fry. Methods: Lactobacillus casei from Yakult® was used as a starter, and enhanced with Curcuma xanthorrhiza , Kaempferia galanga and molasses. The mixture was fermented for 7 days prior to use as probiotic in a formulated diet containing 30% crude protein. Four levels of probiotic dosage; 0 ml kg -1  (control), 5 ml kg -1 , 10 ml kg -1  and 15 ml kg -1  were tested in this study. The fish was fed twice a day at 08.00 AM and 06.00 PM at the ration of 5% body weight for 80 days. Results: The results showed that growth performance and feed efficiency increased with increasing probiotic dosage in the diet from control (no probiotic) to 10 ml kg -1  of probiotic dosage and then decreased when the dosage was increased up to 15 ml kg -1 . Conclusions: The best values for all measured parameters were recorded at the dosage of 10 ml kg -1 . Therefore, it was concluded that the optimum dosage of enhanced probiotic for T. tambra fry was 10 ml kg -1  of feed.