Evaluating the effects of dietary allicin-rich extract on the production performance, egg quality, caecal bacterial population and lipid profile of laying hens

Abstract

Abstract Consumers' need to prefer pathogen-free animal products has led nutritionists to increasingly look for alternatives to synthetic additives, of which garlic has been considered as a natural additive. Therefore, a 12-week feeding trial was conducted to determine the potential of the dietary allicin-rich extract on the performance of laying hens. Eight hundred and forty (840) 28 weeks old Bovans Brown laying hens were randomly allotted to two experiments; the first study had four dietary treatments with 6 replicates and 20 birds and the second study had three treatments with 6 replicates and 20 birds per pen using a completely randomised design. The dietary treatments consisted of a negative control (Ncon./C, standard diet without antibiotics), positive control (Pcon./C +, standard diet + 1.0Â g/l oxytetracycline), allicin-rich extract with low concentration (AEL, Ncon. + 0.5Â ml/kg), allicin-rich extract with high concentration (AEH, Ncon. + 1.0Â ml/kg) and allicin-rich extract in drinking water (AE/C - + 1.0Â ml/l of fresh drinking water). No statistical differences (PÂ >Â 0.05) were observed in feed consumption and egg weight among all the treatments but egg production, egg mass and feed conversion ratio were significantly improved (PÂ <Â 0.05) by the addition of allicin-rich extract at 0.50Â ml/kg. Albumen was significantly superior (PÂ <Â 0.05) in the AE group compared to the positive control group. With age, viable total coliform, E. coli and Clostridium perfringens were significantly lower (PÂ <Â 0.05) in the experimental groups compared to the negative control group. Significantly lower (PÂ <Â 0.05) concentrations of total cholesterol, triglycerides and low-density lipoprotein were recorded in the AE group. It can be concluded that the incorporation of dietary allicin-rich extract reduced pathogenic bacteria and boosted feed efficiency, egg production and blood lipid depending on the mode of application.