Effect of probiotic administration methods on carcass quality and lipid - protein oxidation rate in Japanese Quail's meat

A total of 336 one-day old Japanese quail chicks were divided in 7 groups for investigating the effect of probiotic administration methods on carcass quality of Japanese quail (Coturnix coturnix japonica). Protexin (Protexin, Somerset, UK) was used as a probiotic. Experimental groups were including: 1. Control group (no probiotics treatment), 2. Continuous in-drinking water probiotic supplemented, 3. Intermittent in-drinking water probiotic supplementation in every 2 d out of 4 d pattern, 4. Intermittent in-drinking water probiotic supplementation in every 1 d out of 5 d pattern, 5. Continuous in-feed probiotic supplemented, 6. Intermittent in-feed probiotic supplementation in every 2 d out of 4 d pattern, 7. Intermittent in-feed probiotic supplementation in every 1 d out of 5 d pattern. The in-feed probiotic supplemented groups received 150 g/ton and 100 g/ton probiotic product in the starter (1-14) and the finisher (15-35), respectively. As the drinking water is approximately two folds of feed intake, the drinking water groups received half amount of probiotic, which was supplemented in feed to balance for different in water and feed consumptions. Carcass weight and percentages of ether extract, protein and ash in dry matter did not show significant differences between administration methods and control group (P>0.05). Dry matter percentage significantly increased by using probiotic (P<0.05). Tiobarbituric acid reactive substances (TBARS) were determined as an index of lipid oxidation development. Data analyseis showed significant differences in TBARS content measured in fresh samples (P<0.01). Carcasses of continuous in-feed probiotic supplemented birds had the lowest lipid oxidation (P<0.01). The other methods only showed insignificant reduction of TBARS. Carbonyl content of fresh samples was determined as an index of protein oxidation development. All administration methods except intermittent in-feed (1 d out of 5 d) resulted in significant reduction of protein oxidation (P<0.05).