IntroductionFluorine occurs throughout the world in soils, plants, water, and animal tissues.Because of its chemical reactivity, it is found in nature in a combined form.Cattle normally ingest variable amounts of fluorides ( u p to 15 ppm F in dry matter) throughout their lives with no known adverse effects. If amounts above the borderline critical level (which varies with the animal species and the type of fluoride) are ingested over long periods of time, fluorine toxicosis may result. Because fluorine is cumulative in the animal body as long as the animal continues to ingest a constant or increasing amount, the major fluorine problem in livestock has involved chronic toxicosis. This has become an important toxicologic problem in some areas in this and other countries.Various sources may contribute to the total fluorine intake by animals. The most commonly encountered sources of excessive fluoride are: ( 1 ) forages subjected to air-borne contamination in areas near certain industrial operations that heat fluorine-containing materials to high temperatures and expel fluorides; (2) drinking water high in fluoride content; ( 3 ) feed supplements and mineral mixtures high in fluoride content; and (4) vegetation growing on soils high in fluoride content.It is generally accepted that the toxicity of a fluoride compound increases as its aqueous solubility increases. Recent experiments with dairy cattle that were fed controlled amounts of different fluorides have indicated that calcium fluoride is less toxic than sodium fluoride or than hay containing fluoride emitted from a n industrial plant (FIGURE 1).Elevated vegetation levels of fluorine generally result from increased atmospheric fluorides. In at least some cases, a large fraction of these fluorides seems to be deposited on the surface of the leaves and, thus, can be readily removed by rain or washing. Particulate fluorides are more likely to accumulate on plant surfaces than gaseous fluorides. Surface contamination of plants by fluoride in dust o r mud splashed on leaves near the ground may also occur and contribute

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Bursas were taken weekly as normal turkeys developed from 3 to 22 weeks of age, and no specific bacterial or viral infection was found. Bacterial cultures were also made of condemned bursas taken at processing. Of 144 collected, 91% were sterile; the others had staphylococci, streptococci, or coliform organisms. Experiments with turkeys measured the effect of strain, body conformation, completeness of breast-feather cover, protection of the keel with sheepskins, age when put on range, and type of range on the incidence of enlarged sternal bursas. The strain difference of 25.4% breast blisters against 11.5% was highly significant (99% confidence). In one experiment the effect of feather cover was significant at the 95% level of confidence (61.7% breast blisters with no feather cover, versus 40% with complete feather cover). The effect of protecting the breast with sheepskin was significant at the 95% level of confidence in reducing incidence of breast blisters. There was no significant difference in the incidence of breast blisters in relation to body conformation, age, or type of range.

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