Evaluation of the effect of peptidyl membrane-interactive molecules on avian coccidia

Abstract

This study examined the lytic effect of seven different synthetic peptidyl membrane-interactive molecules (Peptidyl-MIMs) on sporozoites of five different species of Eimeria infecting chickens and merozoites of two different species that infect chickens. All Peptidyl-MIMs (pMIMs) demonstrated antiparasitic effects at concentrations of 1-50 microM during incubation periods varying from 1 to 20 min. In addition, electron microscopy showed that ultrastructural degeneration of the pellicle of sporozoite stages of the parasites occurred within 5-10 min of exposure to 5-microM concentrations of three different pMIMs. Pore-like openings were seen in the pellicle of the sporozoites at the ultrastructural level, which indicated that the pMIMs had the same mechanism of action on the parasites as that reported from studies done on bacteria. A reduction in lesion scores was seen in chickens treated orally with 10-, 50-, or 75-microM concentrations of two different proteolytic stabilized (methylated) pMIMs after challenge with three different species of avian coccidia in battery-cage trials. Collectively these data indicate that pMIMs may be useful in the control of coccidiosis in poultry.

Recent Advances in Biology and Immunobiology ofEimeriaSpecies and in Diagnosis and Control of Infection with These Coccidian Parasites of Poultry

“…Peptidyl membrane-interactive molecules are known to have antibacterial activities. Three of seven tested produced ultrastructural damage to sporozoite pellicles after a 5-to 10-min exposure to 5 M concentrations in vitro (67). Oral doses (10, 50, or 75 M) of two of them, which were methylated to prevent proteolysis, reduced lesion scores from challenge infections with E. acervulina, E. tenella, and E. maxima, suggesting that they have potential for coccidiosis control.…”