CAFO refers to an agricultural facility housing a large number of animals for a period of 45 days or more, with no land being used for crops, grazing, or foraging.
CAFOs can be small, medium, or large based on the number of animals. A large cattle CAFO is anything at or above 1,000 cows, while a small turkey CAFO may have as many as 16,500 turkeys. The size of the CAFO determines its requirements under government regulations, including EPA oversight.
CAFOs are very different from traditional agriculture and animal husbandry practices, in that they create a controlled, overpopulated, and unhealthy environment, in contrast to a pasture-based farm.
We wrote a detailed FAQ on the subject matter including the negative environmental impact in this article.