The primary reasons for citing sources in a research paper are to give credit to the authors whose work you have drawn upon and to allow readers to track down your sources, should they wish to explore further. There are many style guides for formatting citations and creating bibliographies. Many Animal Science professors ask that you use the format from the Journal of Animal Science, but you may be called upon to use others.
Use the citation format from the Journal of Animal Science. Here's an example for a journal:
McKendree, M. G. S. , C. C. Croney and N. J. O. Widmar. 2014. . J. Animal Sci. 92:3161-3173.
For more examples, check the "Instructions for Authors" section of the journal. Here's the link: