Effects of Feeding Zinc, Manganese, and Copper Amino Acid Complexes and CobaltGlucoheptonate to Dairy Replacement Heifers on Claw Disorders

Abstract

AbstractFive hundred seventy-two Holstein replacement heifers were fed a control diet or control diet plus complex trace minerals (CTM), which included 360mg zinc/d, 200mg manganese/d, and 125mg copper/d from amino acid complexes and 12mg cobalt/d from cobalt glucoheptonate. Dietary treatments were fed from 12 mo of age until 1 mo prepartum. Heifer claws were examined at 12 mo of age, 1 mo prepartum, and 2 mo postpartum. All claws disorders were identified and scored for severity on a scale of 1 = mild to 3 = severe. A claw disorder incidence and severity index (CIS) was calculated by multiplying, for each disorder, number of zones affected in each claw by average severity score of the disorder by 10. Heifers with claw disorders at 12 mo of age or at 1 mo prepartum had increased odds (P≤0.05) of developing claw disorders at 2 mo postpartum. Supplementing growing heifers with CTM increased (P≤0.05) CIS for sole hemorrhages and tended to increase (P≤0.15) CIS for claw disorders and heel erosion at 1 mo prepartum. Compared with control heifers, heifers fed CTM during rearing had a lesser (P≤0.05) CIS for white line separation and tended to have a lesser (P≤0.15) CIS for overall claw disorders and sole ulcers at 2 mo postpartum. In conclusion, presence of claw disorders during rearing increased risk of heifers developing claw disorders during lactation. Feeding CTM to heifers did not reduce incidence of claw disorders during rearing, but reduced incidence of claw disorders in early lactation.