Metal concentrations and histopathological changes in goats (Capra hircus) reared near an industrial area of West Bengal, India.

The present investigation was performed to assess the concentrations of four heavy metals-lead (Pb), cadmium (Cd), copper (Cu), and cobalt (Co)-in goats reared in the vicinity of an industrial area of West Bengal, India, including soil, water, and feedstuffs; tissues of liver, kidney, lung, spleen, and muscle; and milk and faeces. In addition, histopathological changes in liver, lung, kidney, spleen, and muscle samples were examined. Mejia block as an industrial polluted site and Vatar block as a reference site (without any industrial activities and 120 km away from the polluted site) were selected for this study. The results showed that concentrations of these heavy metals in soil, water feedstuffs, all tissues, milk, and faeces were greater (P < 0.05) in the polluted site than the reference site. The largest concentrations of Cd and Pb were found in kidney followed by liver, lung, spleen, and muscle. However, Co and Cu accumulations in the tissues were in following order: liver > kidney > lung > spleen > muscle. Concentrations of heavy metals were greater in older animals than in young ones. Haemoglobin, total protein, packed cell volume, total erythrocyte counts, and total leucocytes counts were significantly (P < 0.01) decreased in blood of goats in the polluted site compared with the reference site. Serum glucose, creatinine, aspartate amino transferase, alanine amino transferase, and alkanline phosphatase were significantly (P < 0.05 to P < 0.01) increased. Histological examination showed several pathological alterations including degeneration, vacuolation, and tubulitis in kidney; congestion, degeneration, periportal necrosis, and focal haemorrhages in liver; and congestion and diffuse haemorrhage in lungs. It was concluded that natural exposure to these environmental heavy metals significantly increases toxic heavy-metal concentrations in several visceral organs resulting in pathological changes in these tissues. Thus, consumption of the meat of goats reared in the polluted site may pose human health hazards.