Comparative scanning electron microscopical studies were carried out on Chonopeltis australis Boxshall, 1976 collected from different localities in the Orange-Vaal River System in South Africa and on material of Chonopeltis minutus Fryer, 1977 and Chonopeltis australissimus Fryer, 1977 on loan from the Albany Museum, Grahamstown. This elucidates the fine structure of morphological features, which are of taxonomic importance and illustrates the significance of the copulatory structures on the legs as a taxonomic tool. It was also concluded that C. australissimus is the same as C. minutus, with C. australissimus the junior synonym.
To study the possibility of immunization against Cryptosporidium baileyi Current, Upton et Haynes, 1986 with the attenuated anticoccidial vaccine, Paracox™ and oocysts of C. parvum Tyzzer, 1912, chickens were inoculated orally with either 3 x 10’ vaccine oocysts or 8 x I O5 C, baileyi or C. parvum oocysts at 1 week of age. The inoculation with Paracox™ vaccine and C. parvum oocysts was repeated at 2 and 3 weeks of age. Uninfected birds served as controls. All animals with the exception of one uninfected group were challenged orally with either 8 x 105 C. baileyi or 3 x 10s Eimeria tenella Railliet et Lucet, 1891 oocysts at 4 weeks of age. Sera were collected at 4 weeks of age, and were examined by ELISA using C. baileyi antigens. Birds inoculated with C. parvum oocysts did not shed C. parvum oocysts in their faeces, but anticryptosporidial antibodies could be detected in the sera. The total oocyst output of C. parvum inoculated chickens was 17% of that of previously uninfected birds after the oral challenge with C. baileyi. Considering that antibodies play no or only a minor role in resistance to C. baileyi, these results suggest that inoculation of chickens with C. parvum oocysts stimulated also cellular immune response. Based on the relative body weight gain, faecal scores, oocyst output, mortality, and caecal lesions in the birds immunized with Paracox™ vaccine and challenged with E. tenella, the vaccination induced only a moderate protection against the reinfection. The results of crossimmunization of chickens with Eimeria spp. and C. baileyi suggest that attenuated anti-eimerian vaccines do not induce any protection against cryptosporidial infection.
In Capillaria pterophylli Heinze, 1933, two lateral bacillary bands extend along the whole body in female and male worms. A ventral bacillary band is present in females only. The bacillary bands consist of glandular and non-glandular cells, and in the region between the nerve ring and the end of the sticliosome, ciliated sense receptors in tight connection with gland cells are present.
The contribution of woodiniee (Apodemus sylvaticus), yellow-necked mice (Apodemus flavicollis) and bank voles (Clethrionomys glareolus) was compared in a focus of Lyme borreliosis in Switzerland during a 7 months’ study. All three species of mice and one species of shrews (Sorex araneus) were shown parasitized by infected Ixodes ricinus immatures. About 14% of larvae and 50% of nymphs collected on small mammals were infected with B. burgdorferi. Spirochetes were isolated from blood of 3 woodmice and one yellow-necked mouse. The infectious status of rodents was estimated by tick xenodiagnosis. Prevalence of infected rodents ranged from 20% to 44%. Mice presented a higher potential infectivity than voles. The prevalence of infected rodents showed a seasonal variation.
The methods of spatial statistics were applied to assess the geographical pattern of risk of Lyme borreliosis in Central Bohemia, the Czech Republic, based on retrospective data on disease contractions. The statistical risk was then compared at 15 selected localities with the infection challenge presented by ticks and insects carrying borreliae. Over 5,000 Ixodes ricinus (L.) ticks and 390 hacmatophagous dipterans were screened by direct immunofluorescence method, and the spatial and seasonal variance of infection rates were studied. Infected ticks were found at each locality throughout the warm season; in nymphs, sample infection rates ranged from 4.9% to 23.1% with a mean of 14.5% in spring, from 7.7% to 28.7% with a mean of 16.1% in summer, and from 7% to 20.6% with a mean of 13.6% in autumn. The statistical risk was found to correlate well with an average nymphal infection challenge, i.e. I. ricinus nymphal abundance x infection rate, at a given locality. Statistically significant cumulation of insect-history recalling patients into several, generally wetland, areas was ascertained; borreliae were revealed in 0.5% of the dipterans examined.
Fourteen three-month-old rabbits spontaneously-infected with the microsporidium Encephalilozoon cuniculi Levaditi, Nicolau et Schoen, 1923 were inoculated intravenously with lymphocytes (Ly) from seropositive bovine leukemia virus infected cattle (Ly/BLV) or with fetal lamb kidney cells infected with bovine fetal leukemia (FLK/BLV). Thirteen rabbits were seropositive to BLV at least for a period of three months. Six rabbits died of pulmonary lesions. Chronic inflammatory lesions of ence-phalitozoonosis were found in six rabbits killed between 454 and 548 days of the observation period. Five animals bore subcutaneous granulomas. Immunohistochemically, E. cuniculi was demonstrated in the inflammatory lesions of rabbits studied. Control animals also spontaneously infected with E. cuniculi did not show clinical signs of encephalitozoonosis. Morphological changes were found incidentally in the form of small glial foci and focal interstitial nephritis in these animals. The combined action of BLV - E. cuniculi on the bodies of rabbits is proposed as a suitable model for the study of encephalitozoonosis in man with human immunodeficiency virus (HIV) infection.