Chapman D P, Bacon W L, Long D W, Kurima K, Burke W H
Department of Poultry Science, Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691-4096.
Gen Comp Endocrinol. 1994 Oct;96(1):63-74. doi: 10.1006/gcen.1994.1159.
Changes in the secretory pattern of luteinizing hormone (LH) were determined in turkey hens during initiation of reproduction. Photosensitive hens were switched from a short day photoschedule of 6L:18D (light:dark) to 14L:10D and serially bled six times during the next 6 weeks of photostimulation and early after ovulatory cycles had begun. The pattern of LH secretion at 0-1 day of photostimulation was characterized by a low baseline concentration of LH with numerous low frequency, high amplitude pulses. This pattern changed at Days 4-5 and 11-12 of photostimulation (hens photostimulated but not yet laying) to a pattern characterized by a high baseline with few ill defined pulses of very short duration. Once the hens had initiated egg production, ovulatory surges of LH (duration of 358 +/- 104 min) were superimposed on the basic pattern seen during photostimulation. The ascending limb of the ovulatory surge was much shorter in duration than the descending limb. No diurnal variation was detected in baseline concentration before or during photostimulation or after egg production had begun. It was concluded that photosensitive turkey hens secrete LH in low frequency; high amplitude pulses superimposed on a low baseline. During photostimulation, this pattern changes to one characterized by a high baseline with few pulses of low amplitude and short duration. This pattern of secretion is stimulatory to the ovary and continues until egg laying begins when it is modified by ovulatory surges of LH, characterized by short duration ascending limbs and longer duration descending limbs, which are superimposed on the high baseline pattern noted during photostimulation.
在母火鸡繁殖初期，对促黄体生成素（LH）分泌模式的变化进行了测定。将对光敏感的母鸡从6小时光照：18小时黑暗的短日照光照周期转换为14小时光照：10小时黑暗的光照周期，并在接下来6周的光照刺激期间以及排卵周期开始后的早期连续采血6次。光照刺激0 - 1天时LH的分泌模式特点是LH的基础浓度较低，伴有大量低频、高幅度脉冲。这种模式在光照刺激的第4 - 5天和第11 - 12天（母鸡接受光照刺激但尚未产蛋）发生改变，变为基础浓度较高且伴有少数持续时间极短、界限不清的脉冲的模式。一旦母鸡开始产蛋，LH的排卵峰（持续时间为358±104分钟）叠加在光照刺激期间所见的基础模式之上。排卵峰的上升支持续时间比下降支短得多。在光照刺激前、光照刺激期间或产蛋开始后，未检测到基础浓度的昼夜变化。得出的结论是，对光敏感的母火鸡以低频分泌LH；高幅度脉冲叠加在低基础浓度之上。在光照刺激期间，这种模式转变为以高基础浓度为特征、伴有少数低幅度和短持续时间脉冲的模式。这种分泌模式对卵巢有刺激作用，并持续到开始产蛋，此时会被LH的排卵峰所改变，排卵峰的特征是上升支持续时间短、下降支持续时间长，且叠加在光照刺激期间所观察到的高基础浓度模式之上。
