Animals sold for food are frequently diseased due to poor living conditions and fattening practices, contaminating their bodies.

Original passage

Often animals are taken to market and sold for food when they are so diseased that their owners fear to keep them longer. And some of the processes of fattening them for market produce disease. Shut away from the light and pure air, breathing the atmosphere of filthy stables, perhaps fattening on decaying food, the entire body soon becomes contaminated with foul matter.