Immunity to coccidiosis: maternal transfer in Eimeria maxima infections

Abstract

Chicks hatched from eggs laid in the third and fourth weeks after inoculation of the hens with oocysts of E. maxima excreted fewer oocysts in response to a challenge inoculum of E. maxima given at 1 week of age than controls hatched from the eggs of uninfected hens. A λ-livetin fraction prepared from the yolks of eggs laid by hens 14–22 days after a single inoculation of oocysts of E. maxima and injected subcutaneously into 2-week-old chicks caused a similar reduction in oocyst yield from a challenge inoculum. The serum of the donor hens, obtained at the corresponding time intervals was protective. These results confirm that immunity to infection with E. maxima is, at least in part, mediated by humoral antibodies.