Photoperiodic time measurement is maintained in undernourished lambs with delayed puberty.

摘要: Beginning at 42 weeks of age undernourished females that had been maintained outdoors were exposed to long days (15L:9D) or short (9L:15D). After 6 weeks, both groups placed on days, and ad-libitum feeding was begun. Rapid 'catch-up' growth occurred similarly in groups. However, the response oestradiol negative feedback regulation LH secretion differed greatly. Short-day lambs remained hyperresponsive inhibition, circulating low, a condition typifies immaturity system governing secretion. In long-day-short-day sequence, began increase 10 after end days; this change is characteristic neuroendocrine alteration occurs during puberty. These findings indicate growth-retarded lamb can differentiate from therefore continue accumulate photoperiod information prolonged periods undernutrition.