Showing papers on "Babesia published in 1981"

Bovine babesiosis: protection of cattle with culture-derived soluble Babesia bovis antigen

Abstract: Adult Hereford (Bos taurus) cattle were protected from severe reactions and death caused by the tick-borne protozoan hemoparasite Babesia bovis, 3 months after vaccination with a cell culture--derived immunogen. The immunogen consisted of filtered, freeze-dried supernatant fluid collected from long-term cultures of Babesia bovis in vitro. It was reconstituted with saponin adjuvant and injected twice subcutaneously at 2-week intervals. Serum collected from vaccinated cattle caused thickening of the merozoite surface coat, aggregation, and lysis of merozoites in vitro. This reaction was identical to that caused by serum from immune carrier cattle suggesting that the protective antigen present in culture fluids is merozoite surface coat antigen. No mortality occurred among vaccinated cattle, whereas mortality among unvaccinated cattle and Babesia bigemina--immune cattle was 62.5 percent indicating that immunity to bovine babesiosis is species-specific.

Studies on a bovine Babesia transmitted by Hyalomma marginatum rufipes Koch, 1844

Abstract: A Babesia sp. was recently observed in Hyalomma marginatum rufipes and found to be transmissible to bovines. Further observations were carried out on this parasite and a study made of the morphology of stages in both erythrocytes and tick haemolymph. Apart from Babesia divergens, intra-erythrocytic parasites were not readily distinguishable from bovine Babesia spp. Merozoites in tick haemolymph morphologically resembled those of Babesia bigemina, but they were significantly larger. This Babesia sp. proved to be highly infective for adult H. m. rufipes, with transmission taking place transovarially and next generation nymphae and adults transmitting the infection. Features of the infection were its very low pathogenicity, even in splenectomized animals, and the tendency of parasitized erythrocytes to accumulate in capillaries. Serologically, this species could be differentiated from babesia bigemina, B. divergens, B. bovis and B. major. A serological survey of 25 farms showed a wide distribution of this species in south Africa and its high rate of transmission on most properties. It was concluded that this is a true but hitherto undescribed bovine Babesia sp. and the name Babesia occultans n. sp. is proposed.

Schizonts and Tick Stages in Immunization Against Theileria annulata Infection

Abstract: Almost 60 years ago Sergent et al (1924) noted that blood from cattle acutely ill with Theileria annulata invariably produced theileriosis when inoculated into susceptible cattle. This fact provided a solid basis for using blood from infected cattle for immunization purposes, as was being done in the case of other bovine intracellular hemoparasites (Babesia and Anaplasma). The initially high mortality, caused by needle transmitted infection with field isolates, was partially overcome by using isolates of naturally low virulence (Sergent et al, 1932). However, even such strains produced clinical theileriosis in most inoculated cattle and resulted in 1.8% mortality (Tsur, 1949).

Babesia crassa n.sp. (Sporozoa, Babesiidae) of domestic sheep in Iran.

Abstract: Summary A large Babesia sp., isolated from a sheep in Iran, proved to be serologically and morphologically different from B. motasi and B. ovis. The parasite, designated B. crassa n. sp., is characterized by the frequent occurrence of four organisms in one erythrocyte, which is the result of quadruple division and, in other cases, of two successive binary divisions. Parasites resulting from the first of two successive binary divisions are exceptionally broad. B. crassa appears to be of low pathogenicity for sheep and goats, to which it is also infective. The vector is unknown.

Infections with blood parasites in the small British rodents Apodemus sylvaticus, Clethrionomys glareolus and Microtus agrestis.

Abstract: Three populations of small wild British rodents were studied by capture–recapture methods over a period of 3 years, a fourth group was studied for 1 year and a fifth was sampled annually for 4 years. Blood smears were taken from 3 species of rodents: the woodmouse A podemus sylvaticus, the bank vole Clethrionomys glareolus (and an island sub-species C.g. skomerensis) and the short-tailed vole Microtus agrestis. The smears were examined microscopically. Four genera of haemoparasites Babesia, Hepatozoon, Trypanosoma and Grahamella were detected. Babesia was absent from C.g. skomerensis, Hepatozoon was rarely found in A. sylvaticus and M. agrestis and Trypanosoma was rare in A. sylvaticus. More males were infected than females but the difference was only statistically significant for the infection with Hepatozoon in adult C.g. skomerensis. Infections with Babesia and Hepatozoon were more prevalent in adult animals and infections with Trypanosoma were more prevalent in younger individuals. Only in C.g. skomerensis was there a significant difference between age classes in the prevalence of infection with Grahamella – there being more adults infected. Concurrent infections were detected, Hepatozoon being the parasite most commonly involved. The prevalence of infections was found to be approximately proportional to the number of animals known to be alive, regardless of the season.

[A study on the transmission (transstadial, transovarial) of Babesia microti, strain "Hannover i", in its tick vector, Ixodes ricinus (author's transl)].

Abstract: Transstadial, transovarial and combined transstadial-transovarial transmission of Babesia microti in its tick vector, Ixodes ricinus, was studied. The ticks used (larvae, nymphs, females) were part of the progeny of nymphs collected in an area nearby Hanover. Specimens to be infected alimentarily were fed on parasitaemic Golden Hamsters (Mesocricetus auratus). The ability to infect mammalian hosts of a tick stage was examined by feeding it on negative Golden Hamsters. B. microti was found to be transmitted transstadially from the alimentarily infected larva to the following nymphal stage, only. Thus, this nymph is the only stage transmitting the Babesia to mammalian hosts. Transovarial transmission could not be observed.

Raccoon babesiosis in connecticut, usa: babesia lotori sp. n.

Abstract: A species of Babesia which infects raccoons, Procyon lotor, is described and named Babesia lotori. Twelve of 14 raccoons captured from five counties in Connecticut developed parasitemia after splenectomy. Preoperative levels were subpatent or less than 1%. Parasitemia peaked anywhere from less than 5% to 36.6% in splenectomized raccoons, and all but one survived and possessed low infection rates (less than or equal to 3%) at the end of the experiment. An indirect fluorescent antibody test is described and shown to be useful in detecting antibodies to B. lotori. Seropositive raccoons were obtained from six counties. Two, Babesia-free, splenectomized raccoons developed parasitemia with corresponding increases in antibody titers after they were inoculated with infected blood. Antibody titers of naturally infected raccoons following splenectomy either remained stable or increased fourfold. Babesia was observed in three of four young raccoons which had been naturally confined to chimneys. Two of these four young raccoons were infested with a nest-dwelling tick, Ixodes texanus.

Isolation and transmission of an unidentified Babesia sp. infective for cattle.

Abstract: Engorged adult female ticks submitted from farms in South Africa were routinely screened for protozoan parasites by examination of haemolymph smears. An unidentified Babesia sp. was found in Hyalomma marginatum rufipes and its transmission to susceptible cattle was achieved both biologically (tick feeding) and mechanically (injection of infected blood). Attempts to transmit this species to susceptible rabbits and a horse using similar methods did not produce evidence of infection. This Babesia sp. was of low pathogenicity, even in splenectomized cattle. Morphologically, intra-erythrocytic piroplasms and merozoites in tick haemolymph resembled other bovine Babesia spp. in many respects. Although it could be classified as a large Babesia, it was intermediate in size between the other species.

Field use of an irradiated blood vaccine to protect cattle against redwater (Babesia divergens infection) on a farm in Dorset

Abstract: A field trial was conducted in Dorset to determine whether calves could be protected against babesiosis by the prior inoculation of irradiated blood infected with Babesia divergens. The trial involved 99 Friesian heifers. Forty were inoculated with infected blood from a donor calf after the blood had been irradiated to a dose of 28 kilorads, 31 were immune animals which had grazed on the infected site the previous year and 28 were susceptible animals. After exposure on a hillside where there was a high risk of contracting the disease, 21 of 28 susceptible animals became clinically affected by redwater and required treatment whereas no animals in the other two groups were affected. It was shown that there was a 100 per cent risk of disease at the site and serological and haematological evidence corroborated the clinical results in demonstrating total protection of the vaccinated animals. Vaccination against redwater appears preferable to therapy, since vaccination before exposure on an infected pasture can replace frequent monitoring of the animals and subsequent therapy late in the course of the disease.

Investigations on a Babesia isolated from Scottish sheep.

Abstract: The pathognomic, serologie and morphometric identity of a Babesia sp. recently isolated from sheep in Argyllshire was studied. Initially, problems were encountered due to the occurrence of Eperythrozoon ovis as a contaminant of the isolate and treatment with neoarsphenamine failed to remove it. Finally, a combination of oxytetracycline therapy and rapid passage allowed isolation of the Babesia sp. and its preservation in the form of a glycerolized, infected blood stabilate. Inoculation of the stabilate into splenectomized sheep produced a mild non-pyrogenic disease. Serologically the parasite was seen to have no affinity with either of the two Babesia recognized as parasitizing sheep, but some affinity with the cattle parasite B. divergens. Morphometrically it was seen to have affinity with the deer parasite B. capreoli and with the Babesia sp. isolated from red deer in Scotland, and the low number of budding forms of the parasite seen suggested that the parasite might be reproducing slowly in an alien host. It was concluded that the parasite was likely to be B. capreoli derived from red deer via the tick Ixodes ricinus.

Bovine Theileriosis and Its Control in Japan

Abstract: The cattle population of Japan was about 3.7 million in 1974 and increased to approximately 4.2 million by 1979 following implementation of grazing programmes to increase the production of animal protein in Japan. A nationwide survey conducted in 1970 revealed that piroplasmosis was the most important disease affecting grazing cattle, and this situation still remains. As mixed infection with Theileria and Babesia is common in Japan, theileriosis and babesiosis have collectively been called piroplasmosis.

Inhibition of Babesia spp. by plastics.

Abstract: Five commercially available plastic containers were compared with glass for toxicity toward Babesia rodhaini and Babesia bigemina. Comparisons were made by using infectivity tests in mice (B. rodhaini) and cattle (B. bigemina). Low-density polypropylene and polystyrene containers were not toxic, but two of the three polyvinyl chloride containers tested significantly reduced the viability of both species of Babesia. Plasticizer present in various amounts on the surface of the toxic containers was most likely the inhibitory material.

Transmission expérimentale de Babesia bigemina à des moutons à l'aide de larves infectantes de la tique Boophilus decoloratus

Abstract: Babesia bigemina is known to be transmitted in Nigeria by Boophilus decoloratus which parasitises cattle (DIPEOLU, 1975). In another survey on ectoparasites of cattle, sheep and goats, DIPEOLU (1975) found out that Boophilus decoloratus also > parasitises sheep. Although Babesia motasi and B. ovis are the Babesia species found in sheep in Nigeria Babesia bigemina has not been demonstrated or reported in the blood of sheep.

Effect of experimental Babesia bigemina infection on the haematological values of splenectomized white Fulani calves.

Abstract: Quatre veaux blancs Fulani ont été splénectomisés. Trois ont été expérimentalement infectés par Babesia bigemina à l’aide de larves infectieuses de Boophilus decolorancs ; le quatrième a servi de témoin. L’évolution des principaux paramètres de leur sang a Bt6 observée pendant 40 jours avec les résultats suivants : chez les veaux infectés, tant les valeurs de Phématocrite que celles des érythrocytes ont progressivement diminué à partir du 5= jour après l’infection alors que ces valeurs sont restées constantes chez le veau témoin. Par contre, le taux de leucocytes a augmente chez les quatre animaux mais de façon plus sensible chez les veaux splénectomisés, cc qui semblerait indiquer que cette augmentation est à mettre pour une faible partie seulement au compte du stress opératoire.