[Fluorosis in cattle].

Fluorosis is a chronic disease caused by the body weight produces clinical signs after continued continued ingestion of small but toxic amounts of ingestion. fluorine in the diet or drinking water over a long duration In case of pregnant cows the fluorine content of leading the cumulative effect, while acute poisoning bones of new born calves depends on the dam’s intake occurs due to inhalation of fluorine containing gases by of fluorine in the last 3-4 months of pregnancy. smoke, vapours, dust from industries of aluminum, Epidemiology copper, glass, enamel, iron, steel and super The common causes are drinking water from phosphate. Dust from volcanic eruptions also contain deep wells, artesian bores, industrial contamination of large amount of fluorine. Accidental administration of pasture and the feeding of fluorine from phosphatic large amount of fluorine leads to fluorosis. rock supplements / limestone usually occurs in animals Etiology suffering from phosphorus deficiency. Death losses are The toxic effects of fluorine depend on the rare and restricted largely to acute poisoning. But the major losses are due to the unthriftiness caused by amount ingested into the body, the solubility and bioavailability of it. When level exceeds 100 ppm of chronic fluorosis. fluorine in ration utilizing the source of fluorine as rock Pathogenesis & Necropsy Findings phosphate or cryolite likely to cause diseases in cattle. Normal cattle have blood levels of up to 0.2 mg Calcium fluoride or sodium fluorosilicate is relatively fluorine per deciliter of blood and 2-6 ppm in urine. The non-toxic and an intake of 400 mg to 2 gm/kg of body detoxification process takes place if intake is very high weight is necessary to have fatal effects. Sodium fluoride is nearly twice toxic and general level of 50 ppm in the form of deposition of fluorine in association with phosphate before irruption of teeth. The deposition is of dry ration should not be exceeded, otherwise induces fluorosis. Mottling of tooth enamel occurs at 27 greatest in long bones on periosteal surfaces and ppm, moderate effects at 49 ppm level. Where as bony exostosis occurs due to excessive mobilization of light lesions are observed at 27 ppm, moderate at 49 calcium and phosphorus at any age in life. The bone ppm level and marked at 93 ppm. Milk production in les ions l i ke os teomalec ia , os teoporos is , dairy cows is not affected at 50 ppm of fluorine in the osteofluorosis, hip lameness and stiffness of limbs, diet up to fourth lactation. Fluorine in excess of 2 ppm in painful gait, un-thriftiness are the characteristic clinical water is toxic to animals. symptoms. Palpably and visibly enlarged bones Minor teeth lesion occurs at 5 ppm, while when particularly the mandible, sternum, metacarpal, the level exceeds of 10 ppm the excessive wear and metatarsal and phalanges become short, thicker, tear of tooth occurs. More systemic effects occur when broader, porous, brittle, hence are prone to fracture. the water contains 30 PPM of fluorine. Chronic Periosteal hyperostosis or exostosis at joint or at intoxication occurs when bore water contains 12 – 19 places of attachment of ligaments and tendons cause ppm fluorine. shifting pain and lameness. Degenerative changes are When daily intake of fluorine is 0.5 to 1.7 mg/kg seen kidney, liver, adrenal glands, heart muscle, body wt. in the form of sodium fluoride produces dental adrenal glands and central nervous system, bone lesions in growing animals without affecting general marrow and aplastic anemia. Fluorine does not pass health, whereas the adult animals can tolerate double placental barrier hence new borns are not affected until the dose of the above intake i.e. 1 to 3.5 mg/kg. body they begins to drink water. weight per day is sufficient to cause severe dental Clinical findings fluorosis without affecting growth rate or reproductive function. An intake of 1 mg/kg body weight is the In case of acute intoxication there is ruminal maximum safe limit for ruminants. An intake of 2 mg/kg stasis, constipation or gastroenteritis occurs due to