Christensen V L, Grimes J L, Wineland M J, Davis G S
Department of Poultry Science, College of Agriculture and Life Sciences, North Carolina State University, Raleigh, North Carolina 27695-7608, USA.
Poult Sci. 2003 Dec;82(12):1863-8. doi: 10.1093/ps/82.12.1863.
The hypothesis was proposed that shorter incubation periods and faster growth rates for long-stored eggs would improve embryonic survival and poult hatchling quality. Increased incubation temperatures were tested for their efficacy in improving embryonic livability in fertilized eggs stored for 15 d prior to setting in the incubator compared to controls stored for only 3 d. Two temperature treatments were applied. In experiment 1, a 37.8 degrees C set point for dry bulb temperature was used to accelerate development for the initial 2 wk compared to the controls at 37.5 degrees C. Following treatment, the accelerated embryos were returned to the same machine as the controls. In experiment 2, higher temperature exposure was only for the initial week of incubation. The temperature and storage treatments were in a completely random 2 x 2 factorial arrangement of treatments. At the completion of 28 d of incubation, survival rates of all treatments were determined by opening all nonhatching eggs to differentiate truly fertilized eggs from unfertilized. Hatchability was determined by dividing the total number of poults on a hatching tray by the number of fertilized eggs on a tray. Incubator trays were the experimental unit. Tissues were sampled in both experiments to verify treatment effects on growth and metabolism. Hatching times were observed at 4-h intervals during the actual hatching process beginning at 25 d of incubation. It was concluded that delayed growth and depressed metabolism of fertilized turkey eggs stored for 15 d can be compensated for by exposure to higher incubation temperatures for the initial 1 or 2 wk of incubation.
长期储存的种蛋孵化期缩短和生长速度加快会提高胚胎存活率和雏禽孵化质量。与仅储存3天的对照种蛋相比，测试了提高孵化温度对储存15天的受精种蛋孵化时胚胎存活力的影响。采用了两种温度处理方式。在实验1中，与设定干球温度为37.5℃的对照组相比，在最初2周使用37.8℃的设定温度来加速胚胎发育。处理后，加速发育的胚胎与对照组胚胎放回同一台孵化机。在实验2中，较高温度处理仅在孵化的第一周进行。温度和储存处理采用完全随机的2×2析因设计。孵化28天后，通过打开所有未孵化的种蛋以区分真正的受精蛋和未受精蛋来确定所有处理的存活率。孵化率通过将孵化盘上雏禽总数除以盘上受精蛋数来确定。孵化盘是实验单位。在两个实验中都采集了组织样本，以验证处理对生长和代谢的影响。在孵化第25天开始的实际孵化过程中，每隔4小时观察一次出雏时间。得出的结论是，储存15天的受精火鸡种蛋生长延迟和代谢受抑制的情况可通过在孵化的最初1或2周内采用较高孵化温度来弥补。
