Langendijk P, Dieleman S J, Gerritsen R, Hazeleger W, Mainsant M-L, Soede N M, Kemp B
South Australian Research and Development Institute, Roseworthy Campus, Roseworthy, SA 5371, Australia.
Reprod Fertil Dev. 2007;19(8):961-6. doi: 10.1071/rd07117.
The present paper describes luteal phase luteinising hormone (LH) in sows that ovulated due to a limited nursing regimen (LN). The LN regimen was imposed either at Day 14 or at Day 21 of lactation. At ovulation, lactation was terminated (n = 8) or sows remained lactating throughout early pregnancy (n = 8). Blood samples were collected every 15 min for 8 h during the day, around Day 11 after ovulation. In addition, lactating sows were bled during the night, when piglets were allowed to suckle. The LH pattern was typical for the luteal phase, with one to five pulses per 8 h. The LH characteristics (frequency, base, average, pulse area) did not differ between lactating and weaned sows, except for the amplitude of LH pulses, which was higher in weaned sows compared with lactating sows (1.22 +/- 0.15 v. 0.76 +/- 0.11 ng mL(-1), respectively; P < 0.05). In lactating sows, average LH, basal LH and the frequency of LH pulses were significantly lower during the night, when piglets were allowed to suckle. The sage of lactation at which LN was imposed did not influence LH. In conclusion, it is unlikely that the small difference in LH explains the considerable difference between lactating and weaned sows in progesterone at Day 12 of pregnancy (24.1 +/- 1.3 v. 43.3 +/- 4.0 ng mL(-1), respectively; P < 0.01). Moreover, the difference in progesterone already exists during the early luteal phase (Day 0-10), when secretion of the corpora lutea is still independent of LH.
本文描述了因有限哺乳方案（LN）而排卵的母猪黄体期促黄体生成素（LH）的情况。LN方案在泌乳第14天或第21天实施。排卵时，泌乳终止（n = 8）或母猪在妊娠早期全程保持泌乳状态（n = 8）。在排卵后第11天左右的白天，每隔15分钟采集一次血样，共采集8小时。此外，泌乳母猪在夜间仔猪吮乳时采血。LH模式为黄体期典型模式，每8小时有1至5个脉冲。泌乳母猪和断奶母猪的LH特征（频率、基线、平均值、脉冲面积）无差异，但LH脉冲幅度除外，断奶母猪的LH脉冲幅度高于泌乳母猪（分别为1.22±0.15和0.76±0.11 ng mL⁻¹；P < 0.05）。在泌乳母猪中，夜间仔猪吮乳时，平均LH、基础LH和LH脉冲频率显著降低。实施LN的泌乳阶段不影响LH。总之，LH的微小差异不太可能解释泌乳母猪和断奶母猪在妊娠第12天孕酮水平上的显著差异（分别为24.1±1.3和43.3±4.0 ng mL⁻¹；P < 0.01）。此外，在黄体早期（第0 - 10天）孕酮差异就已存在，此时黄体分泌仍独立于LH。
