5. Conclusions
The present study demonstrates that: (1) both kisspeptin and NKB are coexpressed in geese ovary; and (2) concentrations of kisspeptin and NKB vary during reproductive cycle of geese; (3) kisspeptin is positively correlated with NKB, but they are both inversely correlated with estradiol level in the serum of geese. These results are
suggestive of their role in the regulation of reproductive cycle in the geese.
Conflict of interest statement
We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work; there is no profes- sional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled.
Acknowledgments
This work was supported by the National Natural Science Foundation of China (Grant no. 31472096), and Specialized Research Fund for the Doctoral Program of Higher Education from Ministry of Education Science and Technology Development Center, Beijing, P. R. China (Grant no. 20123418110004).