In essence, the purpose of organic farming is to work as a partner with nature to promote natural and compassionate husbandry of plants and animals while conserving soil and water resources. As mandated by the USDA National Organic Standards, soil and plants are not treated with toxic chemicals or persistent pesticides. No toxic fertilizers or sewage sludge is used to promote growth, nor are genetically engineered seeds allowed. Animals are fed organic feeds and their natural behaviors must be accommodated to make their lives as comfortable and stress-free as possible. The use of synthetic growth hormones and antibiotics are forbidden.