The UC Davis Dairy is an on-campus animal facility of the Department of Animal Science located on Dairy Road. An average of 100 cows are milked twice daily, with all the milk being sold to Hilmar Cheese to be made into delicious dairy products. The closed herd consists of two of the six dairy breeds: Holsteins and Jerseys.
For those who like to complain, the dairy "is the primary reason that UCD has a stigma of smelling like cows. It is indeed the source of the Essence of Davis. This teaching facility, located well within smell range of the Tercero dorms (especially for that of buildings B and C), helps animal science majors learn the fine art of milking cows."
For more information, see the Dairy's website