Use well-composted manure rather than fresh. Fresh manure has the potential to burn plants. For perennial crops such as asparagus and rhubarb, fertilize after the harvest season is completed. Avoid the use of cat, dog, or pig manures in gardens or compost piles. Some of the parasites found in these manures may survive and remain infectious for people.
Some people are especially susceptible to food-borne illnesses.
These people should use good food handling practices or avoid eating uncooked vegetables from manured gardens. Manure has and will continue to be an excellent garden fertilizer. As with many things we use, certain precautions should be taken to prevent potential problems. Iowa State University , Ames, Iowa. This information subject to a usage policy .