Hansen L H
Nord Vet Med. 1979 Mar;31(3):122-8.
In a herd of sows 106 sows having 4.3 litters on aver., were over a period of 10 weeks treated on Thursdays with 0.175 mg of cloprostenol on the 111th to 114th day of gestation; 93--95% of the sows treated on the 112th and 113th day farrowed within 33 hours after treatment, 73% after treatment on the 111th day (Table I); the mean period of gestation after treatment was 113.4 +/- 0.9 days. 8 sows that only farrowed 2--5 days after the treatment, had on 21 previous farrowings proved to have significantly longer mean periods of gestation, 115.6 days, than the 112 sows in the control group, having 3.6 litters on average, that farrowed in the same period and section of the piggery as the sows treated with cloprostenol. In total 32 weekend-farrowings occurred in the observation period including 7 farrowings after a period of gestation of 110--113 days, 6 cases of unsuccessfully induced parturition and 19 farrowings on the 114th to 119th day that could have been programmed to occur on Fridays; the number of weekend-farrowings, which for this herd in connection with the weaning procedure normally accounted for about 40--45% of farrowings, could thus be reduced to 7% of farrowings (Table II). Cloprostenol treatment on the 111th day resulting in farrowing on the 112th day leads to a significantly higher rate of piglet mortality after 3 weeks compared with the results after farrowing for control sows that farrowed on the 112th day (Table III); this category of control sows had on previous farrowings proved to have a significantly shorter mean period of gestation, 112.7 days, than that of the sows in the cloprostenol group farrowing on the 112th day which had been 114.3 days on previous farrowings. Farrowing and weaning results after induced parturition resulting in farrowing on the 113th to 115th day showed no significant differences from the results for control sows farrowing spontaneously on the 112th to 115th day of gestation. The incidence of MMA (Table II) was not influenced by the cloprostenol treatment, nor by the number of litters, the length of the period of gestation, or by the piling of farrowings on Fridays.
在一群母猪中，106头平均产仔4.3窝的母猪，在妊娠期的第111至114天，于每周四用0.175毫克氯前列醇治疗，为期10周；在第112和113天接受治疗的母猪中，93 - 95%在治疗后33小时内产仔，在第111天治疗后产仔的占73%（表I）；治疗后的平均妊娠期为113.4±0.9天。8头仅在治疗后2 - 5天产仔的母猪，在之前的21次产仔中，其平均妊娠期（115.6天）显著长于同期在猪舍相同区域产仔的112头对照组母猪，对照组母猪平均产仔3.6窝，这些对照组母猪与接受氯前列醇治疗的母猪同期产仔。在观察期内共发生32次周末产仔，其中包括110 - 113天妊娠期后的7次产仔、6例引产未成功以及19次在第114至119天的产仔，这些产仔本可安排在周五进行；该猪群与断奶程序相关的周末产仔数通常占产仔总数的40 - 45%，因此可降至产仔总数的7%（表II）。与在第112天产仔的对照组母猪相比，在第111天进行氯前列醇治疗并于第112天产仔的母猪，3周后仔猪死亡率显著更高（表III）；这类对照组母猪在之前的产仔中，其平均妊娠期（112.7天）显著短于在第112天产仔的氯前列醇组母猪，氯前列醇组母猪之前的平均妊娠期为114.3天。在第113至115天引产并产仔后的产仔和断奶结果，与在妊娠期第112至115天自然产仔的对照组母猪的结果无显著差异。MMA的发生率（表II）不受氯前列醇治疗、产仔数、妊娠期长短或周五产仔堆积情况的影响。
