| Wanxi white goose, a superordinary species in our country, which is characterized with faster growth in the early stage, bearing roughage, low consumption, good quality of meat and pure white feather. However, Wanxi white goose has a lower egg production, poor productivity and high cost for breeding of young goose, all these have restricted the development of goose industry. Zinc is a minor element which is very important to animal growth, development and breeding. In this research, Zinc methionine was added into bait vessel with different doses to study its effect on production performance and reproductive ability from nutrition metabolism and endocrine secretion.In this experiment, four hundred two-year-old Wanxi white goose were randomly divided into four groups with three hundred and twenty female and eighty male goose. With 15% Zinc methionine, Zinc was added into the basic with dose of 0, 60, 80, and 100 mg/kilogram respectively, The results were showed as follow:1. Zinc has no obvious influence on the average egg weight and laying rate of the Wanxi white goose (P>0.05). However, the fertility rate and hatchability of the experimental group were conspicuously higher than the control group when 100mg/kg Zinc was added.2. Zinc has significant effect on some biochemical indicator in serum of Wanxi white goose. During the laying period, serum uric acid for group III was notably lower than the control group (P<0.05); In the highest and resting laying period, the Cu Zn-SOD activity for group III compared with increased 25.03% and 28.06% (P<0.05) respectively. During the whole experiment, ALT and AST production in serum showed no obvious difference not only between the three experiment groups and the control group, but also among the three experimental groups.3. In the initial laying period, for FSH, there is no obvious among between group I, group II and the control group. However, there is significant difference between the group III and the control group. For LH, group II and group III are different from the group I and the control group. For E2, all of the three experimental groups are significantly different from the control group (P<0.05). Furthermore, the group III is extremely different from group I and group II (P<0.01).During the middle of the laying season, for FSH, only the group III appeared to be quite different compared with the control group (P<0.05). Group I and group II showed only a little difference compared with the control group. For LH, all the three experimental groups exhibited conspicuous difference compared with the control group. There was no obvious difference among these three groups. For E2, group II and group III were different from the control group (P<0.01), while the group I showed little difference against the control group (P>0.05).In the resting period, there was no obvious difference between the experimental groups and the control group, considering the contents of FSH and LH in the serum of the Wanxi white goose (P>0.05). The E2 contents for group I and group II was increased (P<0.01);there was no difference between the group III and the control group (P>0.05).4. Zinc can obvious improve the integrity of dodecadactylon and oviducal epithelial tissue, and ameliorate the structure of the epithelial pilus. Immunohistochemistry indicated that there are lots of FSH and LH secreting cells in the pituitary, hypothalamus and ovary tissues.5. Results of immunohistochemistry indicated that FSH and LH secreting cells in the goose serum were not enlarged. So, it maybe that Zinc enhanced the secreting ability of FSH and LH secreting cells, that results in the increase of FSH and LH in serum.Conclusions: adding 100mg/kg Zinc to the basic diet can increase the contents of FSH, LH and E2 in the serum of the Wanxi white goose, enhance the CuZn-SOD activity and cut down the content of unic acid;all these did not obviously change the activity of AST and ALT. |
