Effects of dietary sulfur concentrations on the incidence and pathology of polioencephalomalicia in weaned beef calves.

Abstract

Fourteen heifer calves weighing 174.5+/-17.7 kg were used to evaluate the effects of 3 levels of dietary sulfur. Sodium sulfate added to basal diet made treatments designated moderate (3860 ppm sulfur), moderatey high (5540 ppm sulfur) and high (7010 ppm sulfur). Clinical polioencephalomalacia occurred in all calves assigned to the moderately high and high treatments. The calves did not acclimate to the dietary sulfur as polioencephalomalacia occurred in 4 animals on d 35 and in 1 calf on d 37. Microscopic lesions confirmed polioencephalomalacia in the calves on moderately high and high diets. Microscopic lesions also were present in 4 moderate diet calves although clinical signs were not seen. High dietary sulfur did not limit feed intake. Diets containing sulfur levels >4000 ppm sulfur produced polioencephalomalacia in 10 calves and sub-clinical brain lesions occurred in 4 calves consuming <4000 ppm sulfur.