“…It has long been recognized that different chicken breeds exhibit varying degrees of “susceptibility” to Eimeria species, including tolerance to infection and recovery rates from the pathological consequences of infection ( Attree et al, 2021 ). Progeny of 2 species of White Leghorns showed significantly different survival rates against high-dose challenge by E. tenella ( Palafox et al, 1949 ). Bumstead and Millard (2009) demonstrated that the total oocyst output of 8 inbred lines, including the Houghton Brown Leghorn Line ( BRL ) and the White Leghorn Line N, 151, C, 61, 72, 0, and WL, was significantly different when inoculated with the same dose of sporulated oocysts of E. tenella ( Bumstead and Millard, 2009 ).…”