Gene expression profiles of LH, prolactin and their receptors in female Zi geese (Anser cygnoides) during development.

The objective of this work was to elucidate the gene expression profiles of luteinizing hormone (LH), prolactin (PRL) and their receptors during the developmental and egg laying stage. The expression of genes encoding pituitary LH and PRL, as well as those for the ovarian LH receptor (LHR) and PRL receptor (PRLR), was determined by quantitative real-time PCR in Zi geese on day 1 and at 1, 2, 3, 4, 5, 6, 7 and 8 months of age, respectively. The expression of LH and LHR fluctuated and increased as the geese aged. The expression of LH was significantly higher at 5 to 8 months of age than in 1 day old geese (P < 0.05). The expression of LHR was higher at 8 months than at 1 day, at 1 to 4 months and at 6 months (P < 0.05). The expression of PRL decreased from day 1, followed by an increase from 3 months, and reached the highest values at 8 months of age in the study. The difference in PRL expression between 7 and 8 months of age was significant (P < 0.05). The expression of PRLR decreased initially and this was followed by a fluctuating increase from 5 months until 8 months of age. The expression of PRLR in 1 to 8 month old geese was significantly lower than at day 1 (P < 0.05). These results suggest that LH and PRLR may play an important role in ovarian development and the egg-laying process in Zi geese.