Sulfur Requirement of Lactating Dairy Cows. I. Sulfur Balance and Dietary Supplementation

Two experiments measured the effects of sulfur supplementation of rations for lactating cows. In Experiment 1, a basal diet (Ration 1) containing .10% sulfur was a semipurified concentrate mix and corn silage fed in a 1:1 ratio on a dry basis. Sodium sulfate was added to the basal diet to produce rations containing .15% (Ration 2) and .18% sulfur (Ration 3). The sulfur content of the basal ration was a/so increased to .18% by supplementation with methionine hydroxy analog (Ration 4). Sulfur supplementation of the basal diet increased dry matter intake and dry matter digestibility. Methionine hydroxy analog fed at 43 g/day decreased dry matter intake to the intake of the sulfur deficient diet without affecting daily milk production. Both sodium sulfate and methionlne hydroxy analog improved the sulfur balance of lactating cows with supplements of .15 and .18% sulfur in the complete diet.