Journal or Book Title
Genetics of the Pig
Reproduction, a process essential to maintenance of a species, must be under relatively strict genetic control. This genetic control must ensure that the steps in the reproductive process are repeated with great certainty and precision. Natural selection influenced these steps well before the pig was domesticated over 5000 years ago and humans applied artificial selection. However, nature did not remove genetic variation entirely and humankind has effectively altered the pig to fit social, food and environmental needs.
Rothschild, M. F. and Bidanel, J. P., "Biology and Genetics of Reproduction" (1998). Animal Science Publications. 416.