The effect of garlic (Allium sativum) on growth and immune responses of hybrid tilapia (Oreochromis niloticus x Oreochromis aureus)

Abstract

Juvenile hybrid tilapia (Oreochromis niloticus x O.aureus) were held in 1000 l fiberglass tanks at 27 ºC supplied with a filter and an aeration system. Garlic (Allium sativum) was incorporated into diets (0 %, 0.5 % and 1 %) of juvenile hybrid tilapia, O. niloticus x O. aureus (25.5 ± 1.0 g). Non-specific cellular and humoral responses were evaluated at the beginning and after 2-4 weeks. Total leucocyte count, respiratory burst, phagyctic activity, phagocytic index and lysozyme activity were enhanced in garlic 0.5 % treated groups compared to the control group after 4 weeks. Fish fed with garlic supplemented diets at 0.5 % and 1 % did not exhibit any improvement in growth as compared to those fed with control diet after 2-4 weeks. It is concluded that garlic (A. sativum) at 0.5 % in diet stimulates the immunity of hybrid tilapia (O. niloticus x O.aureus). In addition, body weight gain in juvenile hybrid tilapia that received a diet supplemented with garlic has no growth improvement.