Yahav S, Rusal M, Shinder D
Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel.
Poult Sci. 2008 Jan;87(1):133-7. doi: 10.3382/ps.2007-00359.
Efficient ventilation affects thermoregulation and, thereby, the performance of domestic fowl. This became crucial as genetic selection for growth development significantly coupled with increased metabolic rate. The specific aims of this study were to elucidate a) the effects of different rates of ventilation on young turkey performance during exposure to constant 35, 30, and 25 degrees C and b) their effects on body temperature and surface temperature. In 3 separate experiments, turkeys were raised under regular conditions up to 3 wk of age. Thereafter, they were acclimated for 1 wk to the targeted ambient temperatures (T(a)) and to air velocities of 0.8, 1.5, 2.0, or 2.5 m/s and raised under those conditions up to 6 wk of age. Turkeys exposed to 35 degrees C performed optimally at an air velocity (AV) of 2 m/s; they exhibited significantly higher feed intake and significantly lower body temperature. At 30 degrees C, performance was optimal at AV of 1.5 to 2.5 m/s and significantly lower at 0.8 m/s. Performance of turkeys exposed to 25 degrees C did not vary with AV. Comparison of BW and feed intakes of turkeys exposed to the 3T(a) levels revealed significantly higher feed intake at 25 degrees C but similar BW compared with those exposed to 30 degrees C, meaning that those exposed to 25 degrees C used more energy for maintenance than for growth. In general, surface temperature of the body declined significantly with T(a), whereas that of the face and legs was significantly lower at 25 degrees C. It can be concluded that AV affects the performance of young turkeys. The range of AV within which BW was optimal expanded as T(a) declined. It can be further concluded that the combination of 30 degrees C with AV from 1.5 to 2.5 m/s was optimal for young turkeys.
高效通风会影响体温调节，进而影响家禽的生长性能。随着生长发育的基因选择与代谢率的显著提高紧密相关，这一点变得至关重要。本研究的具体目的是阐明：a）在持续暴露于35、30和25摄氏度的环境下，不同通风速率对幼火鸡生长性能的影响；b）这些通风速率对体温和体表温度的影响。在3个独立实验中，火鸡在常规条件下饲养至3周龄。此后，它们在目标环境温度（Ta）和0.8、1.5、2.0或2.5米/秒的风速下适应1周，并在这些条件下饲养至6周龄。暴露于35摄氏度的火鸡在风速为2米/秒时表现最佳；它们的采食量显著更高，体温显著更低。在30摄氏度时，风速为1.5至2.5米/秒时性能最佳，在0.8米/秒时显著更低。暴露于25摄氏度的火鸡的性能不受风速影响。比较暴露于3个Ta水平的火鸡的体重和采食量发现，25摄氏度时的采食量显著更高，但与暴露于30摄氏度的火鸡相比体重相似，这意味着暴露于25摄氏度的火鸡用于维持的能量比用于生长的能量更多。一般来说，身体的体表温度随Ta显著下降，而面部和腿部的体表温度在25摄氏度时显著更低。可以得出结论，风速会影响幼火鸡的生长性能。随着Ta下降，体重最佳时的风速范围扩大。还可以进一步得出结论，30摄氏度与1.5至2.5米/秒的风速相结合对幼火鸡最为适宜。
