Effect of garlic peel on growth, hematological parameters and disease resistance against Aeromonas hydrophila in African catfish Clarias gariepinus(Bloch) fingerlings

Abstract

Objective To evaluate the efficacy of dietary doses of garlic ( Allium sativum L.) peel on the hematological and disease resistance of African catfish [ Clarias gariepinus(C. gariepinus)] fingerlings against the infections caused by opportunistic bacterial pathogen Aeromonas hydrophila. Methods Powdered garlic peel was incorporated into the diets at (0%, 0.5%, 1.0% and 1.5%) and fed to catfish fingerlings for 20 days. After the feeding trial, biochemical (serum total protein, albumin and globulin), hematological parameters (white blood cells and red blood cells) of the fish were examined. Fish were challenged with Aeromona hydrophila (A. hydrophila) after 20 days of post feeding and percentage mortalities were recorded up to 10 days after post challenge. Results Enhanced serum protein, albumin and globulin in fish fed with all the dosages of garlic peel when compared to control group. Significantly highest red blood cell and white blood cell counts were recorded in garlic peel incorporated diet fed groups compared to control group. The results also demonstrate that low survival rate (55.5±11.0)% in control groups and significantly higher survival rates were recorded in all the garlic peel fed groups after challenging with A. hydrophila. However no significant impact was noticed with regard to body weight gain, specific growth rate and food conversion ratio of fish fed with different levels of garlic peel inclusion and control group. Conclusions These results indicate that garlic peel enhances the hematological parameters even at a low level (0.5%) incorporation and makes C. gariepinus highly immunopotent and more resistant to infection by A. hydrophila.