Eimeria maxima (Apicomplexa): A Comparison of Sporozoite Transport in Naive and Immune Chickens

Abstract

This study compared the early stages of infection in naive and immune chickens infected with Eimeria maxima. An immunoperoxidase stain was developed and used to detect sporozoites and early schizonts in tissue sections of intestinal epithelium. A significantly higher proportion of sporozoites was present in the crypts of naive chickens, 48 hr postinoculation of oocysts, compared to immune chickens. Sporozoites in immune birds tended to remain in the lamina propria rather than migrate to the crypts. Sporozoites were found within intraepithelial lymphocytes (IEL's) in the epithelium, the lamina propria, and the crypts of both naive and immune chickens. Parasites in IEL's of immune birds at the ultrastructural level and there were no apparent morphological abnormalities. Livers and spleens, of both immune and naive chickens that had been inoculated with Eimeria maxima, produced patent infections when fed to susceptible chickens. Infections could be transferred up to 72 hr post-inoculation of the donor birds. Peak oocyst production in the recipient birds occurred 7-8 days after the transfers. This time period approximates the prepatent period in a natural infection and thus implies that the extraintestinal stage was a sporozoite.

Coccidia of rabbit: a review

“…Their experiments showed that this effect was due, at least partially, to the failure of sporozoites transported by IELs to be transferred to crypt enterocytes. Riley and Fernando (1988) found that in immune birds, as compared to nonimmune, a significantly greater number of IELs harbouring sporozoites of E. maxima tended to remain in the lamina propria rather than to migrate to the crypts.…”

Localization of the Initial Developmental Stages of Loma salmonae in Rainbow Trout (Oncorhynchus mykiss)

“…Because of the small size of the fish, whole heart, stomach, and small and large intestine were sampled from five fish at 1, 2,4,8,12,18,24,30,36,42,48,60, and 72 hours PE and 4, 5, 6, and 7 days PE. Every sample was fixed in 4% paraformaldehyde (Sigma) in phosphate-buffered saline (PBS) for 40 minutes at room temperature and then stored at 5 C in 70% ethanol until processed further.…”

Coccidia: A review of recent advances on immunity and vaccine development

“…In E. maxima-immune birds, inhibition of sporozoite transport from the LP to the crypts was reported (Riley & Fernando, 1988). In the case of E. tenella, however, sporozoite transfer from IEL to crypt enterocytes rather than sporozoite transport, is inhibited (Rose et al, 1984c).…”

“…Eimeria vermiformis has been transmitted to uninfected mice by feeding them blood or homogenized lung or liver tissue, but not spleen, from infected mice at 1, 2 and 3 dpi (Ball et al, 1990). Transfer of coccidia between chickens is also possible by feeding blood or homogenates of lung, liver, or heart tissue and, less consistently, spleen, from infected birds at 3 and 4 dpi to uninfected recipients -, Riley & Fernando, 1988. Parenteral administration of oocysts or sporozoites results in the typical intestinal infections (Ball et al, 1989).…”