detection of antibodies in trypanosome-infected cattle by means of a microplate enzyme-linked immunosorbent assay.a micromodification of the enzyme-linked immunosorbent assay (elisa) was evaluated for its potential application in the immunodiagonsis of bovine trypanosomiasis. serum samples from infected and non-infected zebu cattle and samples from friesian cattle with experimental infections were exmained for the presence of trypanosomal antibodies. there were significant differences between the microelisa values obtained with samples from infected and non-infected cattle. during the course of infection mi ...1977333677
east coast fever immunisation trials in uganda: field exposure of zebu cattle immunized with three isolates of theileria parva. 1977413226
exposure of ankole and crossbred cattle to theileriosis in rwanda.susceptible ankole (sanga: bos indicus/bos taurus) and crossbred ankole x jersey (b. taurus) and ankole x sahiwal (b. indicus) cattle derived from a farm in rwanda with no recent history of theileriosis, were infected with theileria parva stocks from rwanda either by feeding infected rhipicephalus appendiculatus ticks on the ears, inoculation of tick derived stabilate or natural exposure to tick challenge. the ankole cattle originated from local stock born and bred in east coast fever (ecf) ende ...19911796523
evaluation of infection and treatment methods in immunization of improved cattle against theileriosis in an endemic area of kenya.five experiments were carried out to determine the efficacy of immunization against theileriosis in an endemic area of kenya using artificial infection with a mixture of stabilates of theileria parva stock or natural infection and treatment with parvaquone or several formulations of oxytetracyclines. for the first four experiments, introduced, susceptible sahiwal/friesian crosses were used and in the fifth, calves of boran/maasai zebu crosses born on the site. cattle were infected either artific ...19902343540
response of nkedi zebu and ankole cattle to tick infestation and natural tick-borne, helminth and trypanosome infections in uganda.a cross-sectional study was conducted in soroti district of uganda to establish important traits of nkedi zebu and ankole cattle regarding their production performance responses to natural infections of trypanosomes, gastrointestinal nematodes, theileria parva, babesia bigemina, anaplasma marginale and tick infestations. over four visits between october 2006 to august 2007, tick counts were performed and blood, faecal samples and sera were collected from the nkedi zebu (295) and ankole (165) cat ...201121350849
demonstration of differences in virulence between two theileria parva areas with a low incidence of infection due to unimodal presence of ticks, theileria parva has been observed to induce a disease with relatively low pathology. this is followed by a carrier state, rather than death and therefore provides a better chance of transmission of the parasite back to the tick vector since in unimodal conditions, the different tick stages occur at different times. one isolate from such an area in zambia, t. parva chitongo, was compared for virulence with t. parva mugu ...201020044208
clinical features associated with seroconversion to anaplasma marginale, babesia bigemina and theileria parva infections in african cattle under natural tick challenge.a longitudinal study was conducted in southeast uganda for 14 months on 640 zebu cattle kept under natural tick challenge, with a view to identifying clinical features for prediction of seroconversion to anaplasma marginale, babesia bigemina and theileria parva infections. physical examination, condition scoring and tick counts were undertaken on all cattle every 4 weeks. in addition, 5300 sera were collected and analysed for antibodies against a. marginale, b. bigemina and t. parva infections u ...200818579313
evaluation of the recognition of theileria parva vaccine candidate antigens by cytotoxic t lymphocytes from zebu cattle.east coast fever (ecf) is a highly fatal lymphoproliferative disease of cattle caused by theileria parva, a tick-borne intracellular apicomplexan parasite. parasite antigens that are targets of protective cytotoxic t lymphocyte (ctl) responses are required to formulate a sub-unit vaccine against ecf. a number of ctl target antigens have recently been identified and initial evaluation has shown their vaccine potential. this study aimed to evaluate whether these antigens were recognised by ctl obt ...200817983665
in vivo comparison of susceptibility between bos indicus and bos taurus cattle types to theileria parva infection.the objective of this study was to determine whether bos taurus cattle differ form bos indicus in their susceptibility to infection with the muguga stabilate of theileria parva and in their resistance to the resultant disease. ten friesians (b. taurus), ten improved borans (b. indicus), ten unimproved borans (b. indicus) and ten zebus (b. indicus) born to dams from an east coast fever (ecf) endemic area were inoculated with an infective dose50 dilution of t. parva muguga stabilate 147. all the a ...200515991702
some preliminary observations on the susceptibility and resistance of different cattle breeds to theileria parva infection.theileria parva-naïve friesian (bos taurus), boran (bos indicus) and maasai zebu steers (b. indicus) were infected with a t. parva sporozoite stabilate dose which had previously been shown to induce an estimated 50% mortality rate in boran cattle. all the cattle developed patent infections with no significant differences in the length of the prepatent period to development of macroschizonts (p > 0.05) between the three groups. clinical theileriosis occurred in all eight the friesians (100%), fiv ...200515991701
evaluation of pcr to detect theileria parva in field-collected tick and bovine samples in tanzania.the ability of pcr to detect infections of theileria parva, the cause of east coast fever, in field-collected tick and bovine samples from tanzania was evaluated. pcr-detected infection prevalence was high (15/20, 75%) in unfed adult rhipicephalus appendiculatus ticks that fed as nymphs on an acutely-infected calf, but low (22/836, 2.6%) in unfed adult r. appendiculatus collected from field sites in tanzania. tick infection prevalence was comparable to that in previous studies that used salivary ...200312591193
identification of a target population for immunisation against east coast fever in coastal kenya.two experiments were carried out to identify the target population of cattle for immunisation against east coast fever (ecf) using the infection-and-treatment method. firstly, a sentinel-calf study was used to determine the age window for ecf immunisation by determining ages at clinical detection of infection with theileria parva. six groups of five naive cross-bred (bos taurus/bos indicus) male calves, introduced at intervals of 2 months at a mean age of 26 days, were exposed to natural tick ch ...200111566376
seroprevalences of vector-transmitted infections of small-holder dairy cattle in coastal kenya.a cross-sectional study was carried out from july to september 1989 in kaloleni division, coast province, kenya to estimate the prevalence of vector-transmitted diseases in small-holder dairy cattle and to identify the risk factors associated with different management systems. one hundred and thirty of the 157 herds with dairy cattle in kaloleni division were surveyed. these were from three agro-ecological zones (coconut-cassava, cashew nut-cassava and livestock-millet), comprised two management ...200111566374
the current epidemiological status of bovine theileriosis in eastern zambia.results of a longitudinal study conducted in the eastern province of zambia from 1994 to 1997 indicate that it is doubtful whether a state of endemic stability of east coast fever (ecf) can be reached in the near future. even in endemic areas, the mortality of theileria parva infections is still estimated above 50%. the main factors limiting progress towards endemic stability are high innate susceptibility of the zebu cattle, the virulence of the parasite and the climate. the unimodal rainfall p ...199910540309
immunization against east coast fever in field cattle with low infectivity theileria parva stabilate--preliminary assessment.two theileria parva sporozoite stabilates stored at -196 degrees c, then at -70 degrees c for six weeks (stabilate 1) and more than six months (stabilate 2) were inoculated into four eight-month old male calves, 1 and 2 (stabilate 1), and 3 and 4 (stabilate 2). calves 1 and 2 developed pyrexia, enlargement of lymph nodes, and the former died of east coast fever. calves 3 and 4 showed slight enlargement of lymph nodes without fever. lymph node smears from all calves (from day 10 to 20 post-inocul ...19989652382
severe anaemia due to haematopoietic precursor cell destruction in field cases of east coast fever in tanzania.examinations were made on erythrocytes, thrombocytes, leukocytes, lymph nodes, thymus, haemal nodes and bone marrow in field cases of east coast fever (ecf) in tanzania. seventy-six clinically sick short-horn zebu and taurine-zebu crosses, positive for theileria parva piroplasms and schizonts and 55 apparently healthy cattle were studied. the syndrome observed was characterised by severe pancytopenia, with massive normocytic, normochromic anaemia, panleukopenia and thrombocytopenia, but no retic ...19948073608
theileria parva carrier state in naturally infected and artificially immunised cattle.rhipicephalus appendiculatus adult ticks, collected in the field from zebu (bos indicus) and exotic (bos tarus) cattle with high antibody titres to theileria parva schizont antigen, transmitted theileria parva infection typical of east coast fever to susceptible cattle. uninfected r. appendiculatus nymphs applied to naturally recovered zebu and exotic cattle kept under tick-free conditions in the laboratory for 16 and 7 months respectively, transmitted fatal theileriosis to susceptible cattle. c ...19957770947
the response of bos taurus and bos indicus cattle types to inoculation of lymphoblastoid cell lines infected with theileria parva a preliminary experiment eight bos indicus type cattle were inoculated with 10(9) cells of a bos taurus lymphoblastoid cell line infected with theileria parva schizonts. four cattle showed patent infections and one died of theileriosis. on challenge of the surviving cattle with a tick derived stabilate of the same stock of t. parva no animal died of theileriosis. to test the susceptibility of bos taurus and bos indicus cattle to cell lines of both cattle types infected with t. parva of the sa ...19826808728
the initial stages of infection of cattle cells with theileria parva sporozoites in vitro.large numbers of theileria parva sporozoites were separated from rhipicephalus appendiculatus adult ticks by filtration and were then concentrated by centrifugation. the sporozoites were incubated at 37 degrees c with leucocytes from 6 cattle of bos indicus and b. taurus types. giemsa-stained smears and living preparations under interference contrast microscopy were used to follow the course of the infection of the leucocytes with sporozoites. sporozoites were seen to attach rapidly to about 25% ...19816791118
effects of tick infestation on boran (bos indicus) cattle immunised against theileriosis in an endemic area of kenya.boran (bos indicus) heifers were immunised by infection with local theileria parva parva, t p lawrencei and t mutans stocks and treated with parvaquone and later exposed to natural tick and tick-borne disease challenge in the trans-mara division of kenya. the theileria species parasites in the challenge were maintained in african buffalo and cattle and the tick vectors were supported by several species of wild bovidae and domestic livestock present in the area. thirty immune cattle were observed ...19854081331
maintenance of theileria parva parva infection in an endemic area of kenya.the maintenance of theileria parva parva infection in an endemic area of kenya on the shore of lake victoria was studied in the field and laboratory. high prevalences of antibodies against t. parva and t. mutans and intra-erythrocytic piroplasms were detected in local zebu (bos indicus) cattle. the mean infection rate of theileria parasites in the tick, rhipicephalus appendiculatus, in field collections was 1.1%. most of the infection was attributed to t. parva parva by application of field tick ...19863092172
immunization of cattle with a theileria parva bovis stock from zimbabwe protects against challenge with virulent t.p. parva and t.p. lawrencei stocks from kenya.following inoculation of 34 bos indicus (boran) cattle with a theileria parva bovis (boleni) stock from zimbabwe, 18 animals underwent mild theilerial reactions, 12 underwent moderate reactions, three suffered severe reactions and one died. when these animals were subsequently challenged with different virulent stocks of either t.p. parva (muguga, marikebuni or mariakani) or t.p. lawrencei (ngong 1 or nanyuki) from kenya, all except two animals resisted challenge. the two reactors were part of t ...19892506688
a clinical trial of buparvaquone in the treatment of east coast fever.a clinical trial was conducted to test buparvaquone (butalex; coopers pitman-moore) in the treatment of east coast fever under field conditions in kenya. data from 229 cases were analysed following treatment with one (69), two (142) or three (18) doses at 2.5 mg/kg. the majority of cattle (95.2 per cent) were exotic (bos taurus) or improved (bos taurus cross bos indicus) and 39.3 per cent were infected with anaplasma marginale. there was an overall recovery rate of 85.6 per cent, with 90.1 per c ...19921441098
population genetic structure of theileria parva field isolates from indigenous cattle populations of uganda.theileria parva causes east coast fever (ecf) a protozoan infection which manifests as a non-symptomatic syndrome among endemically stable indigenous cattle populations. knowledge of the current genetic diversity and population structure of t. parva is critical for predicting pathogen evolutionary trends to inform development of effective control strategies. in this study the population genetic structure of 78 field isolates of t. parva from indigenous cattle (ankole, n=41 and east african short ...201626613662
sequence diversity between class i mhc loci of african native and introduced bos taurus cattle in theileria parva endemic regions: in silico peptide binding prediction identifies distinct functional clusters.there is strong evidence that the immunity induced by live vaccination for control of the protozoan parasite theileria parva is mediated by class i mhc-restricted cd8(+) t cells directed against the schizont stage of the parasite that infects bovine lymphocytes. the functional competency of class i mhc genes is dependent on the presence of codons specifying certain critical amino acid residues that line the peptide binding groove. compared with european bos taurus in which class i mhc allelic po ...201626852329
a review on prevalence, control measure, and tolerance of tanzania shorthorn zebu cattle to east coast fever in tanzania, control of east coast fever (ecf) has predominantly relied on tick control using acaricides and chemotherapy, little on ecf vaccination, and very little on dissemination regarding animal immunization. in this paper, the prevalence, control measure, and tolerance of tanzania shorthorn zebu (tshz) cattle to ecf are reviewed. in addition, the opportunities available for reducing the use of acaricides for the benefit of the farmers in terms of reduction of costs of purchasing acaricides ...201728332070
parasite co-infections and their impact on survival of indigenous natural populations, individuals may be infected with multiple distinct pathogens at a time. these pathogens may act independently or interact with each other and the host through various mechanisms, with resultant varying outcomes on host health and survival. to study effects of pathogens and their interactions on host survival, we followed 548 zebu cattle during their first year of life, determining their infection and clinical status every 5 weeks. using a combination of clinical signs obs ...201424586220
geographic distribution of non-clinical theileria parva infection among indigenous cattle populations in contrasting agro-ecological zones of uganda: implications for control strategies.non-clinical theileria parva infection among indigenous cattle occurs upon recovery from primary disease during the first year of life. continuous exposure to infection through contaminated tick infestations with absence of clinical disease gives rise to endemic stability. endemic stable populations may become sources of infection if contaminated tick vectors are shared with susceptible exotic cattle. this study aimed at establishing a nationwide distribution of non-clinical t. parva infection a ...201425175844
parasite co-infections show synergistic and antagonistic interactions on growth performance of east african zebu cattle under one year.the co-occurrence of different pathogen species and their simultaneous infection of hosts are common, and may affect host health outcomes. co-infecting pathogens may interact synergistically (harming the host more) or antagonistically (harming the host less) compared with single infections. here we have tested associations of infections and their co-infections with variation in growth rate using a subset of 455 animals of the infectious diseases of east africa livestock (ideal) cohort study surv ...201324001119
tick burden and prevalence of theileria parva infection in tarime zebu cattle in the lake zone of tanzania.this study was carried out to assess the distribution, abundance of different tick genera and prevalence of theileria parva infection in tarime zebu cattle kept in selected wards of serengeti and tarime districts in mara region. adult ticks were identified and counted from half body parts of 360 animals which were extensively managed in communal land with natural pastures. concurrently, blood samples were collected and thereafter dna extracted and a nested polymerase chain reaction (npcr) was do ...201425092591
relationship between burden of infection in ungulate populations and wildlife/livestock southern african transfrontier conservation areas (tfcas), people, livestock and wildlife share space and resources in semi-arid landscapes. one consequence of the coexistence of wild and domestic herbivores is the risk of pathogen transmission. this risk threatens local livelihoods relying on animal production, public health in the case of zoonoses, national economies in the context of transboundary animal diseases, and the success of integrated conservation and development initiatives. the ...201323442901
the effect of dexamethasone and promethazine in combination with buparvaquone in the management of east coast fever.the effects of dexamethasone and promethazine on the amelioration of pulmonary oedema in east coast fever were investigated. the clinical effects of these drugs were further investigated when used in conjunction with the antitheilerial drug, buparvaquone. in the first experiment, 15 crossbred (friesian x zebu) steers were divided into four groups. with the exception of the animals in group iv, that served as a control group all the others were infected with theileria parva sporozoites. on the se ...200415373334
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