The Interactive Effects of Zinc Source and Feed Grade Medication on Weanling Pig Growth Performance
Kansas State University Swine Research. Two hundred eight-eight weanling pigs (initially 12.3 lbs and 18 d of age) were used in a 27-d growth assay to determine the interactive effects of Zn source and feed grade medication on growth performance. Experimental treatments were arranged in a 2 3 factorial with main effects of medication (none or 50 g/ton of carbadox) and Zn source (none, 250 ppm of Zn from a Zn amino acid complex, or 3,000 ppm of Zn from ZnO). The results suggest that dietary Zn improved growth performance primarily from d 0 to 14 and feed grade medication improved growth performance from d 14 to 27. Pigs fed diets containing ZnO had better growth performance than pigs fed diets containing no additional Zn, and pigs fed diets containing ZnAA had intermediate responses.