Zinc toxicity, zinc deficiency and zinc-copper interrelationship in Eimeria acervulina-infected chicks
Southern, L.L.; Baker, D.H.
Journal of Nutrition 113(3): 688-696
1983
ISSN/ISBN: 0022-3166 PMID: 6827384 Document Number: 206849
In 3 experiments with young chicks the effect was studied of duodenal coccidiosis caused by Eimeria acervulina infection on Zn toxicity, Zn deficiency and the interrelation between Zn and Cu. The coccidial infection depressed both rate and efficiency of weight gain. Zn at 2000 mg/kg diet depressed performance only slightly, but at 4000 mg/kg reduced both gain and gain:feed ratio. The coccidial infection seemed to have an ameliorative effect on Zn toxicity as assessed by performance and by blood values. Excess Zn (2000 and 4000 mg/kg) dramatically increased liver, pancreas and bone Zn values. The coccidial infection, however, decreased tissue Zn. Copper toxicity caused by Cu 500 mg/kg diet was exacerbated by E. acervulina infection. A Zn-Cu antagonism was observed in control and coccidiosis-infected chicks. Excess dietary Zn decreased tissue Cu deposition, but excess Cu did not affect tissue Zn deposition. Cu partially ameliorated Zn toxicity signs. The efficacy of Cu in overcoming the Zn-induced depressed blood values, however, was improved slightly by coccidiosis. E. acervulina infection did not affect the chick's Zn requirement. Growth results were more reliable as indicators of the Zn requirement than were blood or bone values.