Ward J D, Spears J W, Kegley E B
Department of Animal Science, North Carolina State University, Raleigh 27695-7621, USA.
J Dairy Sci. 1996 Jan;79(1):127-32. doi: 10.3168/jds.S0022-0302(96)76343-9.
Two experiments were conducted to determine the relative bioavailabilities of Cu proteinate, CuCO3, and CuSO4. In Experiment 1, 30 heifers that had been depleted of Cu were us 1. Treatments were control, Cu proteinate A, Cu proteinate B, CuCO3, and CuSO4. Sources provided 50 mg of Cu/d. Supplementation increased plasma Cu by d 21, but there were no differences among the sources. Heifers supplemented with Cu had greater liver Cu concentrations on d 21 than did controls. Heifers receiving CuCO3 had lower liver Cu concentrations than the other heifers. In Experiment 2, 40 heifers were fed diets containing 0.15% of added S and 5 mg of added Mo/kg of DM. Treatments were control, CuSO4, CuCO3, and Cu proteinate A. All sources provided 5 mg of added Cu/kg of DM. Controls and heifers supplemented with CuSO4 had declining plasma Cu concentrations. Supplementation with CuCO3 or Cu proteinate A maintained plasma Cu concentrations. Heifers supplemented with Cu proteinate A had smaller decreases in liver Cu concentrations than did heifers supplemented with other Cu sources. In the absence of high Mo, Cu proteinates were similar in bioavailability to CuSO4. In the presence of high Mo, Cu proteinate A appeared to have a greater bioavailability than CuSO4. Copper carbonate increased or maintained plasma Cu concentrations but was not stored in the liver efficiently.
进行了两项试验以测定蛋白铜、碳酸铜和硫酸铜的相对生物利用率。在试验1中，选用30头已耗尽铜的小母牛。处理方式包括对照组、蛋白铜A、蛋白铜B、碳酸铜和硫酸铜。各来源提供50毫克/天的铜。到第21天时，补充铜使血浆铜含量增加，但各来源之间没有差异。补充铜的小母牛在第21天时肝脏铜浓度高于对照组。接受碳酸铜的小母牛肝脏铜浓度低于其他小母牛。在试验2中，给40头小母牛饲喂含0.15%添加硫和5毫克添加钼/千克干物质的日粮。处理方式包括对照组、硫酸铜、碳酸铜和蛋白铜A。所有来源均提供5毫克添加铜/千克干物质。对照组和补充硫酸铜的小母牛血浆铜浓度下降。补充碳酸铜或蛋白铜A可维持血浆铜浓度。补充蛋白铜A的小母牛肝脏铜浓度的下降幅度小于补充其他铜来源的小母牛。在没有高钼的情况下，蛋白铜的生物利用率与硫酸铜相似。在有高钼的情况下，蛋白铜A的生物利用率似乎高于硫酸铜。碳酸铜可提高或维持血浆铜浓度，但不能有效地储存在肝脏中。
