Effects of Cold Stress on Broiler Performance and Ascites Susceptibility |
A. Ipek*, U. Sahan |
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Correspondence:
A. Ipek, |
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Abstract |
The present study was conducted to determine the effect of cold stress on broiler performance and ascites susceptibility. Male chicks were obtained from a commercial strain of broiler breeders. The trial was divided into two treatments (control and cold stress groups). Ascites was induced in broiler chickens in the trial by exposing the chickens to low temperature (Ta) and by supplying a pelleted diet. The two experimental treatments consisted of: 1) Control group, 33.3째C the 1st wk, 30.2째C the 2nd wk, and 27.5째C the 3rd wk. 2) Cold stress group, 29.0째C the 1st wk, 26.4째C the 2nd wk, and 23.1째C the 3rd wk. From the end of the 3rd wk all broilers were reared to 6 wk of age at a constant temperature of 21째C. There was significant difference in live BW during wk 1 to 5. The control group was consistently the heaviest; however, at 6 wk of age, both groups weighed the same. Body weight gain up to 3 wk was significantly decreased by cold stress. During wk 3 and 6 the chicks in the cold stress group had greater BW gain compared with the chicks in the control group. There were significant differences in mortality due to ascites between the groups. During wk 3 and 6 the cold stress group exhibited the most ascites mortality (9.52%) when compared with the control group (1.90%). At 5 wk of age cold stress condition caused significant changes in packed cell volume (PCV), hemoglobin (Hb) and red blood cell counts (RBC). Right ventricle weight was significantly heavier in the cold stress group than the control. There were also significant differences in right ventricle/total ventricle (RV/TV) ratios at 5 wk. the right ventricle/total ventricle ratios in the cold stress group was higher (0.25) than the control group (0.20). It was concluded that, fast growth and cold temperatures are the primary triggers for ascites during commercial broiler production. |
Keywords:
Broiler; Ascites; Performance Parameters; Cold Stress; Physiological Traits |
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