Heavy metals in drinking water of dairy buffaloes

Dairy farms have emerged around big towns and the water supply is exposed to contaminants from industrial wastes, city drainage and water sewerage. Data were collected from 25 farms. Water and milk samples were analyzed for mineral contents. Mean Cd, Cr and Pb were 0.08, 0.95 and 0.67 (mg l-1) respectively. Zn (r=0.313, P< 0.001) concentration in milk increased with increasing intake of drinking water. Heavy metals Cr, Pb and Cd in milk increased with increasing intake of drinking water. The daily intake of toxic heavy metals Cd, Cr and Pb through milk were 1952.38%, 3896% and 1865.19% above the maximum daily intake of heavy metals from all sources. It is concluded that Mg, Zn and Fe were below the desirable limits while the toxic heavy metals (Cd, Cr and Pb) were above the maximum allowable intake in drinking water. The heavy metals intake through milk alone was much more than the total daily intake of these heavy metals from all sources. Free access to drinking water effected milk yield, body condition and fertility favorably. The higher intake of lead was associated with depressed milk and enhanced level of this element in milk.