Effects of Different Levels of Supplemental Molybdenum on Utilization of Certain Trace Elements and Physiological Responses in Goats

Twelve Black Bengal bucks (8-9m; ~ 5.0 kg) were randomly divided into four equal groups to ascertain the effects of different levels of supplemental Molybdenum (Mo) on utilization of trace elements especially that of copper (Cu), iron (Fe) and zinc (Zn). Feeding of four levels of supplemental Mo at the rate of 0 (Control) 3.5 (T1), 7.5 (T2) and 15.0 (T3) ppm for 120 days did not affect the intake and digestibility of different nutrients. An increase in the level of dietary Mo intake produced a gradient fall in plasma Cu concentration and the lowest value was found in T3 (0.33±0.16 mg ml⁻¹) and T2 (0.33±0.13 mg ml⁻¹) groups of bucks. Increase in dietary Mo intake also reduced the plasma Fe in an identical fashion and at the end of the experiment the lowest plasma Fe concentration was found in T3 group (7.33±0.44 mg ml⁻¹). Supplemental Mo did not affect the plasma Zn level. Mo induced Cu deficiency and decreased (P<0.01) the hemoglobin level in T3 group of bucks followed by T2 (25.30) and T1 (24.22) groups. Consequent to the reduced Cu level in blood, bucks in T3 group exhibited significant (P<0.05) decline in erythrocyte count coupled with a shortened life span and maturation of the erythrocytes. No such effect on leukocyte count was found. It was concluded that higher levels of supplemental Mo induced a copper deficiency which in turn affected the utilization of Fe resulting in development of anemia in goats.