Most cited article - PubMed ID 14574560
The rabbit coccidium Eimeria flavescens Marotel and Guilhon, 1941: an electron microscopic study of its life cycle
To study the immune response to coccidiosis, the suckling rabbits were inoculated with 2,000 oocysts of either Eimeria intestinalis or Eimeria flavescens at 19, 22, 25, 29, and 33 days of age (DA) and in the case of E. intestinalis at 14 and 16 DA as well and sacrificed 14 days later. Another group served as an uninfected control and the rabbits were killed at the same age as their infected counterparts. Unlike the antibody response, the parameters reflecting cellular immunity (total number of leukocytes in mesenteric lymph nodes, lymphocyte proliferation upon stimulation with specific antigen and the dynamics of CD4+ and CD8+ cell proportions in the intestinal epithelium at the specific site of parasite development) were significantly changed from about 25 DA onwards. In contrast to the rabbits infected with weakly immunogenic coccidium E. flavescens, the proportions of CD4+ and CD8+ lymphocytes in intraepithelial lymphocytes from the specific site of parasite development were considerably changed after infection with highly immunogenic species E. intestinalis. As the immune system of sucklings from about 25 DA reacts to the infection, this age may be considered in terms of vaccination against coccidiosis.
- MeSH
- Lymphocyte Activation MeSH
- CD4-Positive T-Lymphocytes immunology MeSH
- CD8-Positive T-Lymphocytes immunology MeSH
- Eimeria classification immunology isolation & purification pathogenicity MeSH
- Animals, Suckling immunology MeSH
- Coccidiosis immunology parasitology MeSH
- Rabbits MeSH
- Specific Pathogen-Free Organisms MeSH
- Antibodies, Protozoan blood MeSH
- Age Factors MeSH
- Animals MeSH
- Check Tag
- Rabbits MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Antibodies, Protozoan MeSH
Suckling rabbits from six litters were orally inoculated at various ages with oocysts of Eimeria flavescens or Eimeria intestinalis. The total number of oocysts in the ceca served to estimate parasite reproduction. The rabbits at 14 and 16 days old remained uninfected, and in 19-day-old animals, low or no oocyst shedding was observed. All the older rabbits were infected and the number of oocysts in the ceca increased with the age of animals at inoculation. The dependence of oocyst production on the age of inoculated rabbits was similar in both coccidian species.
The SPF rabbits were inoculated with oocysts of Eimeria flavescens and the first newly developed oocysts were recovered. They were used for inoculation of other rabbits which consequently excreted oocysts sooner than in the previous passage. By repeated use of this method, the prepatent period was shortened after 18 passages by more than 60 h. The endogenous development of this precocious line (PL) differed from that of the original strain (OS). Compared to OS, two asexual generations, second (or third) and fourth, were absent in PL. The first merogony took place in the jejunum and ileum in OS and, in contrast, in the large intestine in PL. Like in other rabbit coccidia, two types of meronts (A and B) were seen in each generation. However, the ratio of B: A meronts in the last (fifth) asexual generation as well as ratio of microgamonts:macrogamonts differs in OS and PL.
- MeSH
- Eimeria growth & development pathogenicity ultrastructure MeSH
- Coccidiosis parasitology transmission veterinary MeSH
- Rabbits MeSH
- Oocysts growth & development MeSH
- Specific Pathogen-Free Organisms MeSH
- Intestinal Diseases, Parasitic pathology transmission veterinary MeSH
- Sporozoites growth & development MeSH
- Life Cycle Stages * MeSH
- Intestinal Mucosa parasitology pathology MeSH
- Intestine, Small parasitology pathology MeSH
- Intestine, Large parasitology pathology MeSH
- Microscopy, Electron, Transmission veterinary MeSH
- Animals MeSH
- Check Tag
- Rabbits MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
