Al-Rukibat R K, Al-Zghoul M B, Hananeh W M, Al-Natour M Q, Abu-Basha E A
Department of Veterinary Pathology and Public Health, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P. O. Box 3030, Irbid-22110-Jordan
Department of Basic Medical Veterinary Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P. O. Box 3030, Irbid-22110-Jordan.
Poult Sci. 2017 Jan 1;96(1):234-240. doi: 10.3382/ps/pew298. Epub 2016 Sep 1.
The effects of thermal manipulation (TM) at 38.5°C and 40°C for 6 h at embryonic day (ED) 16, 9 h at ED 17, and 12 h at ED 18 on body weight (BW) and cloacal body temperature (T) during the first wk and later at post-hatch d 10, 14, 21, 28, and 42 were evaluated. Furthermore, chicks' ability to cope with a thermal challenge (TC; 41°C for 6 h) at post-hatch d 14 and 42 was also evaluated. A chick's response to TC was measured by determining the cloacal body temperature; the plasma thyroid hormones (thyroxin (T) and triiodothyronine (T)); the packed cell volume (PCV); the heterophil (H), lymphocyte (L), monocyte, basophil, and eosinophil percentages; and the heterophil-to-lymphocyte ratios (H/L). Thermal manipulation did not affect the hatchability. However, the body weight of TM chicken was higher compared with controls at marketing age (post-hatch d 42). At post-hatch d 14 and 42, no significant changes in T were observed among the different treatment groups. However, during TC at d 14 and 42, the T of TM chicks was lower compared with the controls. During TC, a significant increase in plasma T and a significant decrease in plasma T of TM chicks compared with controls were reported. Furthermore, during TC, a significant increase in the PCV and heterophil, monocyte, and H/L ratios, and a reduction in the lymphocyte percentages also were observed in TM chicks compared with the controls. Results of this study showed that chicks subjected to heat manipulation during late embryogenesis respond better to heat stress later in the growth and development period.
评估了在胚胎第16天于38.5°C和40°C进行6小时热调控（TM）、胚胎第17天进行9小时热调控以及胚胎第18天进行12小时热调控，对雏鸡出生后第1周以及随后在出生后第10、14、21、28和42天的体重（BW）和泄殖腔体温（T）的影响。此外，还评估了雏鸡在出生后第14天和42天应对热应激（TC；41°C，持续6小时）的能力。通过测定泄殖腔体温、血浆甲状腺激素（甲状腺素（T）和三碘甲状腺原氨酸（T））、红细胞压积（PCV）、嗜异性粒细胞（H）、淋巴细胞（L）、单核细胞、嗜碱性粒细胞和嗜酸性粒细胞百分比以及嗜异性粒细胞与淋巴细胞比率（H/L）来衡量雏鸡对热应激的反应。热调控不影响孵化率。然而，在上市日龄（出生后第42天），热调控雏鸡的体重高于对照组。在出生后第14天和42天，不同处理组之间未观察到体温有显著变化。然而，在第14天和42天的热应激期间，热调控雏鸡的体温低于对照组。在热应激期间，与对照组相比，热调控雏鸡的血浆T显著升高，血浆T显著降低。此外，在热应激期间，与对照组相比，热调控雏鸡的红细胞压积、嗜异性粒细胞、单核细胞和H/L比率也显著增加，淋巴细胞百分比降低。本研究结果表明，在胚胎发育后期接受热调控的雏鸡在生长发育期后期对热应激的反应更好。
