Clinico-epidemiological observations of industrial bovine fluorosis in India

Abstract

Clinical examination of cattle population in 4 villages around (<3 km) super phosphate fertilizer units in Udaipur district (India) in the month of July for 2 consecutive years (1998 and 1999) revealed occurrence of fluorosis. Prevalence rate of the disease was 27.1% during 1998, Which increased to 46.8% in 1999. Lameness, bony exostosis and dental lesions with varying frequency clinically manifested the disease. Debility, inability to walk and defective mastication were also seen in severely affected animals. Exostosis of metatarsal and metacarpal bones was the most frequently observed sign in the first year, whereas exostosis of ribs was more common sign in the next year. Affected animals had higher concentration of fluoride in serum (range 0.31-1.07 mg/litre in 1998 and 0.13-2.02 mg/litre) and urine (range 5.10-89.10 mg/litre in 1998 and 7.64-51.10 mg/litre in 1999). The serum activity ofaminotransferases and amylase enzymes and concentrations of creatinine and cholesterol were within normal range in the affected animals, but they had higher level of serum urea (7.84 ±0.65 mmol/litre). High fluoride level in fodder (534.4±74.9 mg/kg) and surface water (0.782±0.249 mg/litre in 1998 and 1.186 ±0.286 mg/litre in 1999) contaminated from fertilizer manufacturing units, was suggested as the possible source of excess fluoride ingestion by animals. The study concluded that morbidity and mortality pattern rather than concentration of fluoride in serum or urine are better indicators of continuous exposure of animals to fluoride.