EN
Concentration of selenium in serum samples was determined using a modified Watkinson's spectrofluorometric method. Selenium concentration averaged 0.021 ±0.008 µg/mL for water buffaloes and 0.074 ±0.017 µg/mL for dairy cows. The analysis of selenium concentrations in cows showed deficiency level in 2.0%, marginal level in 64%, and optimal level in 34% of the examined samples. In water buffaloes, deficiency level was found in 96.55% and marginal level in 3.45% of the animals. Selenium levels in cattle and water buffaloes should be periodically diagnosed to provide data for veterinarians to make appropriate decisions. The implementation of suitable prophylactic programmes will enable optimum levels of this element to be maintained.