Morphological and molecular characterization of a pure isolate of Eimeria lata, identified for the first time in domestic chickens in Brazil.

Coccidiosis of domestic chickens is caused by seven Eimeria species, in addition to three recently proposed species: Eimeria lata, Eimeria nagambie, and Eimeria zaria. This study reports the first identification of E. lata in domestic chickens in Brazil, the successful establishment of a pure E. lata isolate, and its morphological and molecular analyses. Fecal samples were collected from six extensive production systems in the state of São Paulo, Brazil, and screened for the 10 Eimeria species of domestic chickens through species-specific PCRs. To obtain E. lata oocysts, a mixture of oocysts from various Eimeria species was sequentially administered to commercial broiler chickens vaccinated against coccidiosis. Subsequently, a pure isolate of E. lata was obtained by micromanipulation and propagated in chickens. Eimeria lata oocysts were further subjected to morphological and molecular characterization. In conclusion, these findings constitute the first documentation of E. lata in domestic chickens in Brazil. The Brazilian E. lata isolate, designated BR-AMC, exhibited molecular and morphological characteristics similar to those of E. lata isolates from other countries.