Estimated copper requirements of Angus and Simmental heifers1
- 1 April 2003
- journal article
- applied animal-science
- Published by Oxford University Press (OUP) in Journal of Animal Science
- Vol. 81 (4), 865-873
- https://doi.org/10.2527/2003.814865x
Abstract
In Exp. 1, Simmental (n = 21) and Angus (n = 21) heifers, approximately 9 mo of age, were used in a 160-d study to determine the effect of dietary Cu on growth and Cu status. Two- or three-yr-old first-calf heifers (21 Angus and 21 Simmental) entering into their last trimester of pregnancy were used in Exp. 2 to estimate Cu requirements of the two breeds during gestation and early lactation. Treatments in both studies consisted of 0 (control), 7, or 14 mg of supplemental Cu (as CuSO4)/kg of DM. The control corn silage-based diets contained 6.4 and 4.4 mg of Cu/kg of DM in Exp. 1 and 2, respectively, and 1.2 mg of Mo/kg. Dietary Cu did not affect performance in either breed in Exp. 1. Copper supplementation generally did not affect plasma Cu concentrations in Angus heifers, but increased (P < 0.05) plasma Cu in Simmental heifers from d 37 until the end of Exp. 1. Final liver Cu concentrations were lower (P < 0.05) than initial concentrations in control Angus and Simmental heifers; however, liver Cu increased (P < 0.01) in Cu-supplemented heifers. In Exp. 2, Cu supplementation of the control diet increased (P < 0.05) plasma Cu during gestation and greatly increased (P < 0.01) liver Cu in both breeds. Calves born to cows not supplemented with Cu also had lower plasma Cu concentrations than Cu-supplemented calves by 73 d of age. In both studies, control Simmental heifers had lower (P < 0.05) plasma Cu concentrations than Angus on most sampling dates. When Cu was supplemented at 7 or 14 mg/kg of DM, few differences in plasma Cu concentrations were observed between breeds. Results suggest that Angus heifers have a lower minimal Cu requirement than Simmental. Based on liver Cu, the control diets containing 4.4 or 6.4 mg of Cu/kg of DM did not meet the Cu requirement of either breed during gestation and lactation or growth. Addition of 7 mg of Cu/kg of DM to the control diets met Cu requirements of both breeds.Keywords
This publication has 11 references indexed in Scilit:
- Effects of breed (Angus vs Simmental) and copper and zinc source on mineral status of steers fed high dietary iron1,2Journal of Animal Science, 2003
- Differences in copper status and copper metabolism among Angus, Simmental, and Charolais cattleJournal of Animal Science, 1995
- Effect of dietary copper, iron, and molybdenum on growth and copper status of beef cows and calvesJournal of Animal Science, 1994
- Effects of dietary copper, molybdenum and sulfur on biliary copper and zinc excretion in Simmental and Angus cattleCanadian Journal of Animal Science, 1994
- REVIEW OF COPPER DEFICIENCY AND METABOLISM IN RUMINANTSCanadian Journal of Animal Science, 1989
- A SURVEY OF MATERNAL COPPER STATUS AND FETAL TISSUE COPPER CONCENTRATIONS IN SASKATCHEWAN BOVINECanadian Journal of Animal Science, 1989
- The long-term accumulation and depletion of copper in the liver of different breeds of sheep fed diets of differing copper contentThe Journal of Agricultural Science, 1983
- Breed differences in copper metabolism in sheepThe Journal of Agricultural Science, 1978
- Relationship between the Level of Copper in the Blood Plasma and Liver of CattleJournal of Animal Science, 1975
- Uses of Aspiration Biopsy TechniqueJournal of Animal Science, 1956