Studies on the growth, chemotherapy and enzyme variation of Eimeria acervulina var. diminuta and E. acervulina var. mivati.

Eimeria acervulina var. diminuta was serially passaged 12 times in chicken embryos, but growth in cultured chick kidney cells was limited to 2 generations of schizonts. After 7 embryo passages the sensitivities of E. acervulina var. diminuta and an embryo-adapted strain of E. acervulina var. mivati to the anticoccidial drugs amprolium, methyl benzyquate, robenidine and sulphaquinoxaline were compared. Both parasites were sensitive to all the anticoccidials but E. acervulina var. diminuta was more sensitive to sulphaquinoxaline and amprolium. The chicken-maintained strain of E. acervulina var. diminuta was extremely sensitive to clopidol, sulphaquinoxaline and decoquinate. Electrophoretic analyses of several enzymes from E. acervulina var. diminuta revealed enzyme profiles with similarities and differences to the embryo-adapted strain of E. acervulina var. mivati.