Richards M P, Augustine P C
Nonruminant Animal Nutrition Laboratory, US Department of Agriculture, Beltsville, MD 20705.
Biol Trace Elem Res. 1988 Sep-Dec;17:207-19. doi: 10.1007/BF02795457.
Two-wk-old broiler chicks were inoculated via crop intubation with Eimeria acervulina at two doses: 10(5) or 10(6) sporulated oocysts/bird or with Eimeria tenella at a dose of 10(5) sporulated oocysts/bird. Serum and liver samples were collected on days 3 and 6 post-inoculation (PI). There were no significant changes in serum or liver zinc, copper, and iron concentrations in any of the infected groups by 3 d PI. However, on d 6, PI serum protein was significantly reduced in all of the infected groups compared to their pair-fed controls. The chicks infected with E. tenella had significantly reduced serum zinc (1.20 vs 1.77 micrograms/mL) and iron (0.44 vs 1.28 micrograms/mL) concentrations and significantly elevated serum copper (0.28 vs 0.17 micrograms/mL) and ceruloplasmin levels (20.33 vs 11.11 micrograms/mL) compared to their pair-fed counterparts. Those chicks infected with E. acervulina (10(6) oocysts/bird) exhibited significantly reduced serum iron concentration by 6 days PI (0.90 vs 1.14 micrograms/mL). Liver zinc was significantly increased in the chicks infected with E. tenella (349 vs 113 micrograms/g dry liver wt), as was copper (24 vs 19 micrograms/g), whereas liver iron concentration was significantly reduced (172 vs 243 micrograms/g) compared to pair-fed controls. At both dose levels, the chicks infected with E. acervulina exhibited a significant reduction in liver iron by 6 d PI. Hepatic cytosol metals generally reflected whole tissue levels. Metallothionein (MT)-bound zinc was significantly elevated in the chicks infected with E. tenella. Iron bound to a high molecular weight, heat-stable protein fraction (presumably cytoplasmic ferritin) was significantly reduced in chicks infected with E. acervulina, as well as those infected with E. tenella. Collectively, the changes in serum zinc, copper, and iron concentrations, as well as the changes in hepatic zinc and MT-zinc concentrations in the chicks infected with E. tenella were similar to changes evoked during an acute phase response to infection. It is possible that a secondary bacterial infection or inflammation stemming from erosion of the lining of the cecum may play a role in the response of trace element metabolism to the E. tenella infection.
10(5) 或 10(6) 个孢子化卵囊/只鸡，或接种剂量为 10(5) 个孢子化卵囊/只鸡的柔嫩艾美耳球虫。在接种后（PI）第 3 天和第 6 天采集血清和肝脏样本。在接种后 3 天，任何感染组的血清或肝脏锌、铜和铁浓度均无显著变化。然而，在接种后第 6 天，与配对饲养的对照组相比，所有感染组的血清蛋白均显著降低。与配对饲养的对应组相比，感染柔嫩艾美耳球虫的雏鸡血清锌（1.20 微克/毫升对 1.77 微克/毫升）和铁（0.44 微克/毫升对 1.28 微克/毫升）浓度显著降低，血清铜（0.28 微克/毫升对 0.17 微克/毫升）和铜蓝蛋白水平（20.33 微克/毫升对 11.11 微克/毫升）显著升高。那些感染堆型艾美耳球虫（10(6) 个卵囊/只鸡）的雏鸡在接种后 6 天血清铁浓度显著降低（0.90 微克/毫升对 1.14 微克/毫升）。感染柔嫩艾美耳球虫的雏鸡肝脏锌显著增加（349 微克/克干肝重对 113 微克/克），铜也增加（24 微克/克对 19 微克/克），而与配对饲养的对照组相比，肝脏铁浓度显著降低（172 微克/克对 243 微克/克）。在两个剂量水平下，感染堆型艾美耳球虫的雏鸡在接种后 6 天肝脏铁均显著降低。肝细胞溶质金属含量一般反映整个组织水平。感染柔嫩艾美耳球虫的雏鸡中金属硫蛋白（MT）结合的锌显著升高。感染堆型艾美耳球虫以及感染柔嫩艾美耳球虫的雏鸡中，与高分子量、热稳定蛋白部分（推测为细胞质铁蛋白）结合的铁显著降低。总体而言，感染柔嫩艾美耳球虫的雏鸡血清锌、铜和铁浓度的变化，以及肝脏锌和 MT - 锌浓度的变化，与感染急性期反应引起的变化相似。盲肠内衬侵蚀引发的继发性细菌感染或炎症可能在微量元素代谢对柔嫩艾美耳球虫感染的反应中起作用。
