Effect of dietary vitamin D 3 supplementation on meat quality of naked neck chickens

Consumers’ interest of indigenous chicken meat is increasing. An experiment was conducted to determine the effect of vitamin D 3 supplementation on meat quality of indigenous male naked neck chickens. Different supplementation levels of 0, 2000, 4000, 6000 and 8000 IU of vitamin D 3 per kg DM of feed were used. 13 weeks old male naked neck chickens with a mean live weight of 1200 ± 3 g were supplemented with vitamin  D 3 for a period of seven days before slaughter. A 2 (cooking or not) x 2 (postmortem agings of 0 or 24 hs) x 5 (vitamin D 3 levels) factorial arrangement in a complete randomized design was used for shear force analysis of raw or cooked naked neck chicken meat. A 2 (postmortem agings of 0 or 24 hs) x 5 (vitamin D 3 levels) factorial arrangement in a complete randomized design was used for sensory evaluation of the meat. A quadratic equation was used to determine vitamin D 3 supplementation levels for optimum shear force value and sensory attributes. Vitamin D 3 supplementation did not improve (P>0.05) shear force values of unaged or aged raw and cooked naked neck chicken meat. Shear force values of unaged raw or cooked meat were optimized at different levels of 3735 (r 2 =0.832) and 2512 (r 2 =0.669) IU of vitamin D 3 per kg DM feed, respectively. Shear force values of aged raw or cooked meat were optimized at different levels of 6728 (r 2 =0.274) and 4249 (r 2 =0.873) IU of vitamin D 3 per kg DM feed, respectively. Vitamin D 3 supplementation had no effect (P>0.05) on unaged meat tenderness, juiciness and flavour. However, vitamin D 3 supplementation improved (P<0.05) aged meat tenderness and flavour. Tenderness, juiciness and flavour of aged naked neck chicken meat were optimized at supplementation level of 6830 (r 2 =0.839), 6894 (r 2 =0.683) and 9795 (r 2 =0.657) IU of vitamin  D 3 per kg DM. It was concluded that vitamin D 3 supplementation improved tenderness and flavour of aged naked neck chicken meat. However, shear force values of unaged or aged raw or cooked naked neck chicken meat were not improved by vitamin D 3 supplementation. Keywords : Shear force, postmortem aging, calpains, connective tissue, tenderness, juiciness, flavor African Journal of Biotechnology Vol. 12(22), pp. 3576-3582