Effect of Adding Antibiotic, Oregano Essential Oil and Garlic Powder on Growth Performance, Carcass Traits and Intestinal Pathogenic Microrganisms of Quails

Abstract

This study was conducted to evaluate the effects of dietary supplementation of antibiotic, oregano essential oil and garlic powder as feed additives in quail diets on the productive performance. A total number of 540 unsexed one week old Japanese chicks were randomly distributed into nine experimental treatments, each of 60 birds (3 replicates of 20 birds each). Chicks of the 1 st experimental group were fed on basal diet without additives and considered as a control group. Chicks of the 2 nd and 3 rd experimental groups were fed on basal diets supplemented with Oxytetracycline at levels of 0.5 and 1.0 g/kg diet, respectively. Chicks of the 4 th , 5 th and 6 th groups were fed on basal diets supplemented with oregano essential oil (OEO) at levels of 0.5, 1.0 and 1.5 g/kg diet, respectively. While, chicks of the 7 th , 8 th and 9 th groups were fed basal diets supplemented with garlic powder (GP) at levels of 0.1, 0.2 and 0.3 g/kg diet, respectively. The present results showed that highly significant differences (p≤0.001) were found in the average body weight (LBW), body weight gain (BWG), growth rate (GR), feed intake (FI), feed conversion (FC), carcass traits, mortality rate, economic efficiency (EE) and the total microbial population count in small intestine. The highest significant improvement in (LBW), (BWG), (GR), (FI), (FC), carcass traits, (EE) and the lowest intestine pathogenic populations content and mortality rate were observed in the group of chicks that were fed diet supplemented with OEO at levels of 1.5 and 1.0 g/kg diet, respectively compared with the other experimental groups and the control group, followed by those that were fed diet supplemented with 0.2 g/kg GP. However, from the economic point of view, it could be concluded that feeding on the basal diet supplemented with GP level of 0.2 g/kg diet showed lower feed cost than feeding basal diet supplemented with OEO at both levels 1.5 and 1.0 g/kg diet. It was clear from the obtained results that the control chicks had the lowest productive performance and the higher mortality rate. Therefore, it could be recommended to use OEO at levels of 1.5 and 1.0 g/kg diet and GP at levels 0.2 g/kg diet as growth promoters instead of antibiotics, to improve the productive performance and the economic efficiency of quails.