Evaluation of pineapple waste crude extract in improving growth performance and resistance to Aeromonas hydrophila in Nile tilapia (Oreochromis niloticus)

The study on the antibacterial activity of fruit, peel, stem, and core of the pineapple, Ananas comosus crude extract against Aeromonas hydrophila and the effect of supplementing the diet with pineapple waste crude extract on growth performance and resistance against A. hydrophila in Nile tilapia, Oreochromis niloticus were conducted. The best result of antibacterial screening was performed by disc method and the minimum inhibitory concentration was found in pineapple fruit extract with an inhibition zone of 7.96±0.20 mm and the minimum inhibitory concentration value was 125 mm per liter. The minimum bactericidal concentration value was not observed in all parts of the pineapple extract at any concentration. Furthermore, Nile tilapia (2.34±0.82 g) were stocked in 12 aquaria and fed a diet supplemented with 4 different doses of pineapple peel extract (0, 1, 2 and 3%) for 8 weeks. The results revealed that the best value of weight gain, average daily weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and feed utilization efficiency was observed in fish fed 1% pineapple peel extract and additionally, the mortality of fish challenged by Aeromonas hydrophila was recorded for 10 days after the challenge. The result showed that fish-fed diet containing 1% pineapple peel extract had significantly the lowest mortality and the highest relative survival percentage.