Nickel Toxicity in the Young Bovine

Abstract

Twenty-three male dairy calves were fed a) 0, b) 62.5, c) 250, or d) 1000 ppm elemental nickel (Ni) as NiCO₂ in the total diet from 13 to 21 weeks of age. Three animals on each treatment were subjected to digestion and balance trials and killed for tissue histological comparisons, and a like number (two for 62.5 ppm) were fed the basal ration in a 6-week posttreatment recovery period. Feed intake and growth rate were slightly retarded by 250 ppm Ni. Even though the calves fed 1000 ppm Ni had greatly reduced feed intake and lost weight during the 8-week treatment period, they were not emaciated and appeared to be younger than the others. During the posttreatment recovery period, growth rate of those which had been given 1000 ppm Ni was at least equal to that of the others. Digestibility coefficients were not affected by the Ni treatments but nitrogen retention was significantly lowered by 1000 ppm Ni and was associated with reduced feed intake. On a molar percentage basis, propionate was increased and butyrate decreased in rumen fluid from animals on the higher levels of nickel supplementation. Relative to body weight, the fresh weight of lung, heart, spleen, liver, gall bladder, kidney, brain, and testis was unaffected by treatments. Nickel did not affect ruminal, abomasal, duodenal, liver and testicular tissues histologically. Kidneys were nephritic, and the degree of severity increased with nickel level.