Six growing female Nubian goats (average BW=34.8+/-0.55kg, 7-8 months of age) were randomly assigned to either a basal diet (BD, 10-15ppm Cu/DM), or to medium Cu (MC, BD+50mgCu), or to high Cu (HC, BD+100mgCu) diets for 9 weeks. This level would cause Cu toxicity in sheep, but none occurred in the goats. Therefore, Cu supplementation was then increased to 150 and 300mg per head per day, for the following 14 weeks; to 300 and 600mg per head per day, for the next 8 weeks; and to 600 and 1200mg per head per day, for an additional 4 weeks, in the MC and HC group, respectively. Body weight and vital signs were recorded and blood samples collected at different time intervals. Hematological parameters, plasma Cu, sorbitol dehydrogenase (SDH), glutamic oxaloacetic transaminase (GOT), and gamma-glutamyl transferase (GGT) were determined. At the termination of the study, tissue Cu concentration in different organs was also determined. During first 23 weeks (<300mgCu per day) of the study there were no apparent signs of Cu toxicity. Cu supplementation at 600mg per head per day in young Nubian does, had no effect on respiration rate (RR), heart rate (HR), and decreased (P<0.05) rectal temperature (RT) in the HC group only. Leukocyte counts were positively correlated with Cu supplementation (r=+0.296, P<0.02) and negatively correlated (r=-0.254, P<0.05) with RT in the HC group. Plasma SDH increased (P<0.05) when Cu supplementation was >/=300mg per head per day, thus, SDH may serve as an early indicator of Cu toxicosis in goats. Increases (P<0.05) in GOT were noted when Cu intake was >/=600mg per head per day. Contrary to the results observed for SDH and GOT, feeding goats 50mgCu per day or more, resulted in an increased plasma GGT as compared to BD goats. Levels of SDH, GOT and GGT of the BD goats were within normal range. Plasma Cu was not indicative of Cu status of animals. Copper improved ADG by 28% at the 100-150ppm level in diet. No relationship between Cu intake and hair Cu was found in the present study. Highest concentration of Cu was found in liver, followed by duodenum, rumen and brain. Results of this study indicate that goats are more resistant to Cu toxicity than sheep. This is one of the first reports documenting significant differences in Cu requirements and tolerance between goats and sheep.

中文翻译：

---

高铜补充剂对山羊性能、健康、血浆铜和酶的影响

六只生长中的雌性努比亚山羊（平均体重 = 34.8+/-0.55kg，7-8 个月大）被随机分配到基础饮食（BD，10-15ppm Cu/DM）或中等铜（MC，BD +50mgCu) 或高铜 (HC, BD+100mgCu) 饮食 9 周。这个水平会导致绵羊的铜中毒，但在山羊中没有发生。因此，在接下来的 14 周内，每头每天补充铜 150 和 300 毫克；在接下来的 8 周内，每头每天 300 和 600 毫克；MC 组和 HC 组分别增加 4 周，每头每天 600 和 1200 毫克。记录体重和生命体征，并在不同的时间间隔收集血样。测定了血液学参数、血浆铜、山梨糖醇脱氢酶 (SDH)、谷氨酸草酰乙酸转氨酶 (GOT) 和 γ-谷氨酰转移酶 (GGT)。在研究结束时，还测定了不同器官中的组织 Cu 浓度。在研究的前 23 周（每天 <300mgCu），没有明显的 Cu 毒性迹象。年轻的努比亚人每天每头补充 600 毫克铜，对呼吸率 (RR)、心率 (HR) 没有影响，并且仅在 HC 组中降低 (P<0.05) 直肠温度 (RT)。在HC组中，白细胞计数与Cu补充呈正相关（r=+0.296，P<0.02），与RT呈负相关（r=-0.254，P<0.05）。当每头每天补充铜>/=300mg时，血浆SDH增加（P<0.05），因此，SDH可以作为山羊铜中毒的早期指标。当每头每天的铜摄入量 >/=600 毫克时，注意到 GOT 增加（P<0.05）。与 SDH 和 GOT 观察到的结果相反，与 BD 山羊相比，每天给山羊喂食 50mgCu 或更多，导致血浆 GGT 增加。BD山羊的SDH、GOT和GGT水平在正常范围内。血浆铜并不代表动物的铜状态。在 100-150 ppm 的饮食水平下，铜将 ADG 提高了 28%。本研究未发现铜摄入量与头发铜之间存在关系。在肝脏中发现了最高浓度的铜，其次是十二指肠、瘤胃和脑。这项研究的结果表明，山羊比绵羊更能抵抗铜毒性。这是最早记录山羊和绵羊之间铜需求和耐受性显着差异的报告之一。血浆铜并不代表动物的铜状态。在 100-150 ppm 的饮食水平下，铜将 ADG 提高了 28%。本研究未发现铜摄入量与头发铜之间存在关系。在肝脏中发现了最高浓度的铜，其次是十二指肠、瘤胃和脑。这项研究的结果表明，山羊比绵羊更能抵抗铜毒性。这是最早记录山羊和绵羊之间铜需求和耐受性显着差异的报告之一。血浆铜并不代表动物的铜状态。在 100-150 ppm 的饮食水平下，铜将 ADG 提高了 28%。本研究未发现铜摄入量与头发铜之间存在关系。在肝脏中发现了最高浓度的铜，其次是十二指肠、瘤胃和脑。这项研究的结果表明，山羊比绵羊更能抵抗铜毒性。这是最早记录山羊和绵羊之间铜需求和耐受性显着差异的报告之一。