Almond P K, Bilkei G
Bilkei, Swine Ethology Studio, Raubbühlstrasse 4, CH-8600 Dübendorf, Switzerland.
Aust Vet J. 2005 Jun;83(6):344-6. doi: 10.1111/j.1751-0813.2005.tb15627.x.
To demonstrate the occurrence of seasonal infertility of sows in large production units in Eastern Europe.
Weaners in this trial originated from a 1000 sow Croatian herd that weaned piglets at 14 or 28 days of age. The production records of 15 indoor (795 to 1849 sows per herd) pig farms with identical feeding, similar genetics and health status, were evaluated. The reproductive performance of sows when the average daily (9 am to 4 pm) temperature was more than 35 degrees C, was compared with the weeks when it was lower than 30 degrees C.
During periods of high temperature (> 35 degrees C) sows had significantly (P < or = 0.05) longer weaning to service intervals and more regular returns to service (P < or = 0.05) compared to weeks of less than 30 degrees C daily temperature in the same summer season. Irregular returns to service were low and showed no significant differences during the same time periods. Farrowing rates and total litter sizes were lower (P < or = 0.05) for periods of higher than 35 degrees C daily temperature compared to weeks of less than 30 degrees C daily temperature in the same summer season.
When daily temperatures are higher than 35 degrees C, reproductive performance is likely to be depressed in large pig production units.
证明东欧大型生产单位中母猪季节性不育的发生情况。
本试验中的断奶仔猪来自克罗地亚一个拥有1000头母猪的猪群，该猪群在仔猪14日龄或28日龄时断奶。对15个室内猪场（每个猪场有795至1849头母猪）的生产记录进行了评估，这些猪场具有相同的饲养方式、相似的遗传背景和健康状况。将平均每日（上午9点至下午4点）温度高于35摄氏度时母猪的繁殖性能，与温度低于30摄氏度的几周进行了比较。
在高温期（>35摄氏度），与同一夏季日温度低于30摄氏度的几周相比，母猪的断奶至配种间隔显著更长（P≤0.05），且返情更规律（P≤0.05）。同期不规则返情率较低，且无显著差异。与同一夏季日温度低于30摄氏度的几周相比，日温度高于35摄氏度期间的产仔率和总产仔数更低（P≤0.05）。
当日温度高于35摄氏度时，大型养猪生产单位的繁殖性能可能会受到抑制。
