Role of Compensatory Gain in Eimeria acervulina-Induced Liver Copper Accumulation in Chicks

Abstract

An investigation was conducted to determine whether the Eimeria acervulina-induced increase in liver Cu accumulation in chicks is the result of compensatory gain that accompanies the recovery phase of infection. In experiment 1, chicks inoculated one time with 1 X 10(6) sporulated E. acervulina oocysts had a faster rate of compensatory gain than chicks inoculated serially on three occasions with 4 X 10(5) oocysts. However, liver Cu accumulation was nearly identical for the two infection regimes. In experiment 2, rate of compensatory gain and liver Cu accumulation was compared in 1) ad libitum-fed chicks; 2) restricted-fed chicks fed 40% of ad libitum intake followed by ad libitum intake; 3) coccidiosis-infected chicks, 1 X 10(6) oocysts on d 2 of the experiment; and 4)-6) the same as 1)-3), respectively, but fed 500 mg Cu/kg diet. Restricted-fed chicks had a higher rate of compensatory gain than coccidiosis-infected chicks. Liver Cu accumulation was sixfold higher in coccidiosis-infected chicks than in restricted-fed chicks, however. In addition, liver Cu accumulation of the control (uninfected) chicks and the 40% restricted-fed chicks was identical. Thus compensatory gain during the recovery phase of coccidiosis is not responsible for the coccidiosis-induced increase in liver Cu accumulation.