Evidence of high-efficiency cross fertilization in Eimeria acervulina revealed using two lines of transgenic parasites

Forward genetic analysis of monensin and diclazuril resistance in Eimeria tenella

“…Since the likelihood of fusion of macro- and micro-gametocytes developed from different schizonts was rare in Eimeria species, most of the output oocysts were self-crossed offspring ( Shirley and Harvey, 1996 ; Liu et al, 2022 ). It will be difficult to isolate a single oocyst from recombinant F1 progeny and also oocysts representing all genotypes after F1 self-crossing.…”

“…This can be explained by the likelihood of cross-over of macro- and micro-gametocytes developed from different parents. Liu et al (2022) demonstrated that about 3–11% of the oocysts were recombinant offspring, while the rest of the oocysts were self-bred from each parent. Thus, different doses of infection or parents with different fitness will result in a biased or polarized distribution of SNPs in the unselected F1 population.…”

“…Experimental evolution and re-sequencing-based methodologies have been successfully used to identify molecular markers for artemisinin-resistant Plasmodium ( Ariey et al, 2014 ) and Toxoplasma ( Rosenberg et al, 2019 ); classical genetic linkage mappings have been performed to identify key virulence factors in T. gondii by crossing with different genotypes of parasites ( Saeij et al, 2006 ; Behnke et al, 2011 ). In the case of Eimeria species, it parasitizes a single host and undergoes both asexual and sexual development during its life-cycle, and genetic crossing could effectively occur at the gamogony stage between different strains ( Liu et al, 2022 ). On the other hand, it is inefficient to isolate single clones for the crossed progeny and also laborious to perform phenotypic analysis of recombinant clones.…”

Microneme-located VP2 in Eimeria acervulina elicits effective protective immunity against infectious bursal disease virus

“…Our work here builds on our recent development of a series of genetically engineered E. acervulina ( 14 , 16 ). For the two transgenic E. acervulina strains which correctly targeted VP2 of IBDV to specific subcellular locations (microneme versus cell surface), microneme-located VP2 was immunogenic enough to induce specific antibody responses against the IBDV, but the surface-located VP2 was suboptimal, in immunized animals.…”

“…Meanwhile, although E. mitis is less pathogenic than E. acervulina , the latter is more practical as it is more prevalent in the field ( 15 ) and commonly used in oocysts-based live vaccines against coccidiosis. Extensive research on E. acervulina , including the selection of precocious and serotinous lines, high-quality and high-resolution genome assembly, as well as the optimization of genetic hybridization system ( 16 ), have resulted in an in-depth knowledge of E. acervulina . Therefore, E. acervulina , with its high immunogenicity ( 17 ), holds greatest potential as a carrier for multivalent vaccines when compared with three other sibling species.…”