Potential of yeast (Saccharomyces cerevisiae) as feed stabilizer and growth promoter on Clarias gariepinus (Burchell, 1822) fingerlings

This research was carried out to examine the potential of yeast as a fish feed stabilizer and growth promoter on Clarias gariepienus with varying levels of baker’s yeast (Saccharomyces cerevisae). Clarias gariepinus fingerlings with mean weight of 2.40 grams fingerlings were obtained from Aliu Farms, Kaduna and transported to the Fishery unit located in the Zoological Garden of the school, Kaduna State University, Kaduna State Nigeria. The fish were acclimatized for two weeks in 60 Liters’ plastic tanks. Fish were stocked at 10 fingerlings per tank containing de-chlorinated tap water in triplicate. Four experimental diets with different inclusion levels of Saccharomyces cerevisiae as follows; Diet I (5%), Diet II (7.5%) Diet III (10%) and Diet IV (12.5%) and the control diet without Saccharomyces cerevisiae were formulated at 40% crude protein. Feed subjected to stability test clearly showed that stability increases with increased level of yeast with Diet IV (12.5%) having the highest at 30 minutes (76%) and 60 minutes (68%). The pelleted feeds were fed to fish at the rate of 5% of the fish biomass throughout the experimental period. The growth response was assessed in terms of daily weight gain, relative weight gain, specific growth rate, feed conversion ratio. The results showed that diet III (10%) gave the best growth performance with an average weight gain of 2.7 followed by diet IV (12.5%) of average weight gain of 2.39 g when compared to the control diet. Similarly, diet III (10%) recorded the highest survival rate of 80%. Thus, adding baker’s yeast cells into commercial fish feed at 10% improved growth and survival of Clarias gariepinus.