ISSN:
1550-7408
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
SYNOPSIS. The ceca of 2-week-old chicks were surgically removed. One week post-operation each cecectomized bird was given 2 × 106 sporulated Eimeria tenella oocysts per os. Birds from the same hatch, with intact ceca, served as controls and were infected the same time as the cecectomized birds. However, in order to reduce mortality, control birds were each given 1 × 104 sporulated E. tenella oocysts per os. Four cecectomized and 5 control birds were killed 12, 24, 48, 72, 96, 120, and 144 hours after inoculation. Tissues from the small and large intestine of each bird proximal to the cecal junction were removed, processed by the dioxan method, and studied microscopically for developmental stages of the parasite. Developmental stages of the parasite were observed in all sections from the large intestine of cecectomized chickens. Initial sporozoite penetration and subsequent development of the parasite in this location was similar to that observed in the cecal mucosa of non-cecectomized chickens. No parasites were observed in sections of the small intestine of cecectomized birds 12 or 24 hours after inoculation, and findings after 48 and 72 hours were inconsistent. However, numerous parasites were observed in sections 96, 120, and 144 hours post-inoculation. In contrast, endogenous stages of the parasite were not seen in tissue sections of the small and large intestine of birds with intact ceca until 120 hours after inoculation. Numerous young gametocytes were then observed in sections from all birds. Similarly, mature gametocytes were observed in all fixed sections 144 hours after inoculation. No evidence was found that would indicate whether or not infection in the small and large intestine of birds with intact ceca or the small intestine of cecectomized birds was initiated by sporozoites or merozoites, nor was evidence found to suggest that development of any stage of the parasite was suppressed in these organs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1550-7408.1969.tb02262.x
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