Effects of Feeding Cobalt Glucoheptonate and Metal Specific Amino Acid Complexes of Zinc, Manganese, and Copper on Lactation and Reproductive Performance of Dairy Cows

Abstract The objective of this review was to evaluate the effects of feeding a combination of cobalt glucoheptonate and specific amino acid complexes of zinc, manganese, and copper ( CTM ; 4-Plex®; Zinpro Corporation, Eden Prairie, MN) on lactation and reproductive performance of dairy cows. In each of eight trials, cows consumed daily 360 mg of zinc from zincmethionine ( ZM ) complex, 200 mg of manganese from manganese-methionine complex, 125 mg of copper from copperlysine complex, and 25 mg of cobalt from cobalt glucoheptonate. In four studies, control and treatment diets contained an equivalent amount of zinc, manganese, and copper. In three studies, control and treatment diets contained an equivalent amount of zinc from zinc-methionine complex. In one study, two comparisons were made; these included complexes vs control and complexes vs sulfates. For evaluation purposes, each trial was considered a block, and each treatment least squares mean within a trial was treated as an observation. Cows fed CTM produced more (P≤ 0.05) milk (36.8 vs 35.7 kg/d), energy-corrected milk (37.9 vs 36.7 kg/d), 3.5% fat-corrected milk (37.7 vs 36.6), milk fat (1.35 vs 1.30 kg/d), and milk protein (1.17 vs 1.14 kg/d) than control cows. The CTM in the diet reduced (P≤ 0.05) days to first service (74 vs 81 d) and days open (115 vs 131 d) and tended to reduce (P≤ 0.10) somatic cell count of milk (301,000 vs 343,000). This summary of eight dairy trials indicates that dietary CTM increases lactation and reproductive performance of cows.