Limitations with current chemotherapeutic and vaccinal control of coccidiosis caused by Eimeria species continue to prompt development of novel controls, including the identification of new drug targets. Glucose-6-phosphate isomerase (G6-PI) has been proposed as a valid drug target for many protozoa, although polymorphism revealed by electrophoretic enzyme mobility has raised doubts for Eimeria. In this study we identified and sequenced the Eimeria tenella G6-PI orthologue (EtG6-PI) from the reference Houghton strain and confirmed its position within the prevailing taxonomic hierarchy, branching with the Apicomplexa and Plantae, distinct from the Animalia including the host, Gallus gallus. Comparison of the deduced 1647 bp EtG6-PI coding sequence with the 9016 bp genomic locus revealed 15 exons, all of which obey the intron-AG-/exon/-GT-intron splicing rule. Comparison with the Weybridge and Wisconsin strains revealed the presence of 33 single nucleotide polymorphisms (SNPs) and 14 insertion/deletion sites. Three SNPs were exonic and all yielded non-synonymous substitutions. Preliminary structural predictions suggest little association between the coding SNPs and key G6-PI catalytic residues or residues thought to be involved in the coordination of the G6-PI's substrate phosphate group. Thus, the significant polymorphism from its host orthologue and minimal intra-specific polymorphism suggest G6-PI remains a valid anti-coccidial drug target.
The present study was conducted to detect the therapeutic effect of Moringa oleifera and Thymus vulgaris oils on hepatic coccidiosis in experimentally infected rabbits. Also, immunomodulatory effect of the two oils was detected. Twenty-four Newzealand rabbits were used in this study and divided into 4 groups; healthy rabbits, experimentally infected rabbits with Eimeria stiedae oocysts, and two infected treated groups (one with moringa (200 mg/kg) and the other with thyme (500 mg/kg) oils). The results showed highly significant reduction in oocysts shedding (P<0.001 and P<0.05) in the two infected and treated rabbits than the infected non-treated rabbits in almost all days post infection (PI). Thyme oil was more potent and stopped oocysts shedding earlier at the day 34 PI compared to moringa oil at the day 41 PI. Microscopically, there was a damage in the oocysts shed by treated rabbits. Macroscopically, the livers of thyme oil treated rabbits showed more enhancement with protection percentage 75% than those treated with moringa oil in which protection percentage was 55%. The highest titer of antibodies was detected in moringa oil treated rabbits. It was concluded that both moringa and thyme oils had an anti-coccidial effect with thyme oil superiority. So, thyme oil could be useful as an alternative product for the control of rabbit coccidiosis.