Research On Serum Biochemical Parameter,Reproduction Hormone Level And Gnrh, Fsh Gene Expression Of Organization In Breeding Geese In Natural Photoperiod

Photoperiod is one of the most important environmental factors in poultry growth and reproduction process. It is proved that duration, intensity, color and wavelength of light, illumination stimulation between initiation and termination could certainly affect the growth and reproduction of poultry, but the mechanism of photoperiod stimulation on the poultry isn’t very clear. Therefore, treat Yangzhou geese as research materials, carry out colorimetric method, electrochemical luminescence method, radiation immune method to determine the serum biochemical and sex hormone level, real-time fluorescence quantitative method (RT-PCR) testing GnRH in hypothalamus and FSH in pituitary expression, seeking for the mechanism influencing Yangzhou geese reproduction performance. The main results are as follows:1, Extended light period leads to a rise in serum TP of Yangzhou geese, but excessive light period stimulation can cause a decrease in the level of TP. The level of serum ALB stays basic stability, which proves that the influence of photoperiod is relatively gentle and explains ALB has an important significance in keeping the stability of internal environment. Extended light period lead to a decline in serum ALP, dark period would increase ALP level, and the high level of ALP is beneficial to improve reproduction performance.Extended light period may apropriately decrease serum BUN level and increase synthesis utilization rate of protein, but as light period stimulation continuous, BUN level continues to rise, point out the body lose more protein.2, Extended light period increase FSH and LH level, which is helpful to the mature and ovulation of follicle.In July and December, female geese PRL level is too high too make an end of reproduction and broodiness traits. In July, male geese have the lowest level of PRL through the whole year, explains gonadal development suffering supression in this period, while at its highest level in December, maintain testicular secretion of testosterone and stimulate the development of sexual accessory gland with the effect of estrogen. In light period longer than dark period time, female geese have higher levels of serum E2than light period shorter than dark period, the change of male geese apears more complex, but excessive light period stimulation could lead to a rise in male geese E2level.3,The relative expression of GnRH in the hypothalamus has declined when light period is longer than dark period, in August, the expression come to the lowest level among the whole photoperiod. When dark period is longer than light period, the expression level shows rising trend, but to the longest dark period December, GnRH gene expression began to lower level,and lasted until march or April when light period began to extend, the expression return to higher level. When light period is longer than dark period, to start with, the relative expression of FSH decrease, then increase to the highest level in June, but in the period of July to September, expression fall to the lower level, meanwhile excessive dark period will also inhibit FSH gene expression.In summary, the four serum biochemical levels:TP, ALB, ALP and BUN, four sex hormone levels:FSH, LH, PRL and E2, GnRH, FSH gene expression of Yangzhou geese showing the corresponding changes with the change of brightness/darkness radio. It is quite likely that brightness/darkness radio among13L:11D at the beginning of reproduction and11L:13D in right reproduction period, in this illumination system, there would be an enhancement in reproduction performance of Yangzhou geese.