Mehmet Akif Yörük

Effects of organically-complexed minerals on meat quality in chickens

1. The impact of combined lower concentrations of organically-complexed versus inorganic copper, zinc and manganese on meat quality in chickens was investigated. 2. A total of 200 male broiler chicks (Ross-308), 1-d-old and weighing approximately 40 g, were divided into 4 groups comprising three experimental groups and one control group, with each consisting of 50 chicks. All groups were also divided into 5 subgroups, with each containing 10 broiler chicks. 3. All birds were given a starter diet from d 1 to d 21, and a grower diet from d 22 to d 49. The diets were formulated according to the NRC recommendations. 4. The mineral contents of the control diet were supplied using a standard inorganic mineral premix (containing 8 mg Cu as CuSO4, 40 mg Zn as ZnSO4, and 60 mg Mn as MnO, per kg). For the experimental diets, a mineral premix was prepared using organically complexed forms of those minerals at 1/3 (L1), 2/3 (L2) and 3/3 (L3) proportions. 5. After slaughtering and evisceration, the carcases were stored at 3 ± 0·5°C for 10–12 h, and then the breast fillets removed from the carcases, and stored in a deep-freezer (−86°C) until analysis (for 30 d). For analyses, the breast muscles were then thawed at 4–6°C for 24 h. 6. The concentration of organically complexed mineral in the diet had no statistically significant effect on pH values of breast fillets. Treatments significantly affected the Thiobarbituric Acid Reactive Substances (TBARS) values. 7. Lightness (L* value) of the fillet from broilers fed the diet containing inorganic minerals was significantly lower than that for broilers fed on the diets containing organically complexed minerals. The redness (a* value) and Chroma (C* value) significantly decreased while Hues (H* value) were higher in the fillet from broilers fed organically complexed minerals compared with those fed inorganic minerals. The yellowness (b* value) was not changed by dietary treatment.

Laying Performance and Egg Quality of Hens Supplemented with Humate and Sodium Bicarbonate during the Late Laying Period

Abstract Yörük, M.A., Gül, M., Hayirli, A. and Laçin, E. 2004. Laying performance and egg quality of hens supplemented with humate and sodium bicarbonate during the late laying period. J. Appl. Anim. Res., 26: 17–21. To determine whether supplementation of humate plus NaHC03 amplifies the effects of their individual supplementation on egg production and quality during the late laying period, two hundred and forty Hisex Brown layers were assigned randomly to receive one of four diets containing no humate and NaHC03, humate (0.1%), NaHC03 (0.1%) or humate (0.1%) plus NaHC03 (0.1%) from week 54 to 66. The experimental diets did not affect the mortality rate. As compared to control (un-supplemented) humate improved egg production, egg weight and feed conversion efficiency, whereas NaHC03 alone or with humate increased feed intake and egg production. Egg quality parameters (specific gravity, shape index, shell stiffness, shell thickness, yolk colour, albumen index, yolk index and Haugh unit) were generally not affected by diet treatments except that NaHC03 alone decreased albumen index and Haugh unit. It is concluded that supplementation of humate or NaHC03 improved laying performance at similar magnitude. However, their combination did not amplify their individual effects.