Toxicological Considerations in Livestock Production

Livestock production practices may result in the distribution of toxic substances to the environment. This has been especially true with concentrated livestock feeding operations that produce large amounts of waste products in small areas. The crowding of animals in these kinds of operations is conducive to the spread of disease so that antibiotics and other agents are often fed to the animals, and these materials and their metabolites appear in livestock wastes. 

Antibiotics are another class of feed additives used in concentrated livestock feeding operations to control disease and increase weight gain. The greatest concern with the long-term subtherapeutic use of antibiotics in livestock feed is the evolution of antibiotic-resistant bacteria. 

FIGURE 10.5 Two organoarsenic compounds that were widely used as additives in chicken feed to control parasites and augment weight gain. 

What is the system called in which plants are grown without soil How does such a system work For what kinds of plants is it used  

A common soil mineral is orthoclase (KAlSijOg). Suggest the kind of secondary mineral found in soil that would be formed by the weathering of orthoclase. 

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