El-Damrawy., S., Abd El-Naby, F., Badawy, N., Zaky, S. (2008). EFFECT OF STOCKING DENSITY ON PERFORMANCE, PHYSIOLOGICAL STRESS INDICATORES, AND IMMUNOLOGICAL STATUS OF BROILERS. Journal of Animal and Poultry Production, 33(5), 3329-3337. doi: 10.21608/jappmu.2008.218004
S. Z El-Damrawy.; Fatma M. Abd El-Naby; Nemat A. Badawy; S. Zaky. "EFFECT OF STOCKING DENSITY ON PERFORMANCE, PHYSIOLOGICAL STRESS INDICATORES, AND IMMUNOLOGICAL STATUS OF BROILERS". Journal of Animal and Poultry Production, 33, 5, 2008, 3329-3337. doi: 10.21608/jappmu.2008.218004
El-Damrawy., S., Abd El-Naby, F., Badawy, N., Zaky, S. (2008). 'EFFECT OF STOCKING DENSITY ON PERFORMANCE, PHYSIOLOGICAL STRESS INDICATORES, AND IMMUNOLOGICAL STATUS OF BROILERS', Journal of Animal and Poultry Production, 33(5), pp. 3329-3337. doi: 10.21608/jappmu.2008.218004
El-Damrawy., S., Abd El-Naby, F., Badawy, N., Zaky, S. EFFECT OF STOCKING DENSITY ON PERFORMANCE, PHYSIOLOGICAL STRESS INDICATORES, AND IMMUNOLOGICAL STATUS OF BROILERS. Journal of Animal and Poultry Production, 2008; 33(5): 3329-3337. doi: 10.21608/jappmu.2008.218004
EFFECT OF STOCKING DENSITY ON PERFORMANCE, PHYSIOLOGICAL STRESS INDICATORES, AND IMMUNOLOGICAL STATUS OF BROILERS
1Animal Production Depart., Faculty of Agriculture, Tanta Univ., Egypt
2Poultry Production Depart., Faculty of Agriculture, Tanta Univ., Egypt
Abstract
The objective of this work was to investigate some physiological stress indicators and immunological status of commercial broilers grown to moderate and large weights with different housing densities. Three hundred and eight one-day-old hybrid broiler chicks were obtained from a commercial hatchery. Chicks were allotted to four groups according to stocking densities of 20, 30, 40, and 50 Kg/m2 (9.1, 13.6, 18.2, and 22.7 birds/m2, respectively). Stocking density was calculated based on an expected final body weight of 2.2 Kg live body weight per bird. Some of live performance traits, physiological stress indicators, and the weight of lymphoid organs were used as indicator of immunity status. The significant effect of 30 kg/m2 stocking density compared with 20 kg/m2 on live performance appeared only at 42 d of age. But increasing stocking density to 40 or 50 kg/m2 significantly decreased Body weight (BW), growth rate (GR), and feed intake (FI) at 28, 35, and 42 d of age. The physiological stress indicators showed that corticosterone (CS), Total Nitrites (TN), glucose (GL), and cholesterol (CHO) were not significantly affected by increasing stocking density (to 50kg/m2 ) up to 35 d of age. But at 42 d, CS, TN, and CHO were significantly increased, especially with 40 and 50 kg/m2. Only at 42 d of age in the present investigation, heterophil to lymphocyte (H:L) ratio was significantly increased by increasing stocking density. Absolute and relative weights of spleen, bursa, and thymus at 42 d of age were significantly decreased as stocking density increased. Thus it could be concluded that, broiler rearing up to 35 d of age (about 1750 g BW) with 20 or 30 kg/m2 stocking densities can protect the birds from the reduction in live performance, reduction immunological status, and increase in physiological stress indicators, especially that this weight (1750 g) is suitable for the marketing process.