N. BOZAKOVA1, S. POPOVA-RALCHEVA2, V. SREDKOVA2, V. GERZILOV3, S. ATANASOVA4, A. ATANASOV1, L. SOTIROV1 and N. GEORGIEVA1
1 Faculty of Veterinary Medicine, Trakia University, BG - 6000 Stara Zagora, Bulgaria
2 Institute for Information Serving of the System, Agricultural Academy, BG - 1113 Sofia, Bulgaria
3 Faculty of Animal Breeding, Agricultural University, BG - 4000 Plovdiv, Bulgaria
4 Agricultural Faculty, Trakia University, Student campus, BG - 6000 Stara Zagora, Bulgaria
BOZAKOVA, N., S. POPOVA-RALCHEVA, V. SREDKOVA, V. GERZILOV, S. ATANASOVA, A. ATANASOV, L. SOTIROV and N. GEORGIEVA, 2012. Mathematical welfare assessment model of chicken breeder flocks. Bulg. J. Agric. Sci., 18: 278-287
The aim of the present study was to evaluate the mathematical welfare assessment model of New Hampshire breeder flocks reared under different production systems and to examine the effect of welfare improvement during the hot period by dietary supplementation with zinc and vitamin C. For this purpose, changes in poultry behaviour, blood corticosterone concentrations and some biochemical blood indices were determined.
Using a mathematical welfare assessment model, the integrated assessment of poultry welfare (PW) of breeders reared indoor on litter was PW = 33.33 %. It was based upon statistically significant changes in different behavioral traits, higher blood corticosterone (P < 0.001), cholesterol (P < 0.001), glucose (P < 0.001), triglycerides (P < 0.01), compared to birds reared in the free-range system. Free range- reared breeders had a PW = 60%.
The dietary supplementation of 35 mg/kg zinc and 250 mg/kg vitamin C contributed to reduction of the adverse effect of stressors in both rearing systems and to improvement of poultry welfare to PW = 60% in indoor-reared breeders and up to 80% in free range-reared breeders.