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sensitive and specific identification of neospora caninum infection of cattle based on detection of serum antibodies to recombinant ncp29.neosporosis is an economically important disease of dairy cattle caused by the protozoan neospora caninum. diagnostic tests for neosporosis are complicated by the potential for cross-reaction of antibodies to antigens that are similar between n. caninum and closely related parasites toxoplasma gondii and sarcocystis cruzi. to provide a sensitive and specific assay for detecting antibodies to n. caninum in the serum of infected animals, we have investigated a recombinant form of the antigen known ...200211986268
[clinical neosporosis in the dog: a review].neospora caninum is an intracellular protozoan parasite that was first recognized in dogs in 1988. n. caninum may cause neuromuscular disease in dogs. later, it was discovered that n. caninum has a wide host range and is an important cause of abortion in cattle. in this article, the literature on n. caninum in the dog is reviewed, with emphasis on clinical signs, pathology, diagnosis, treatment, and prognosis.200011060927
immunity to experimental neosporosis in pregnant sheep.neospora caninum is an important cause of fetal loss in cattle but has also infrequently been shown to cause disease in sheep and goats. experimental infection of pregnant sheep with n. caninum causes clinical and pathological changes very similar to those of neosporosis in cattle. an experiment in sheep was undertaken to examine whether infection with n. caninum before pregnancy conferred immunity to subsequent challenge with the parasite during pregnancy. primary inoculation of nc1 tachyzoites ...200111240899
[the role of the dog in the epidemiology of neosporosis in cattle].neospora caninum is an intracellular protozoan parasite that was discovered in a dog in 1988. since then, n. caninum has been demonstrated in a variety of animal species and it has been recognized as an important cause of abortion in cattle. an infection with n. caninum can be maintained in cattle herds for several generations by transplacental transmission from cow to calf. recently, it was demonstrated that dogs can act as definitive hosts of n. caninum and therefore may be a source of infecti ...200011060928
serological analysis of calves experimentally infected with neospora caninum: a 1-year study.a serological study was conducted with calves experimentally infected with the protozoan parasite neospora caninum. the animals were inoculated with either a low or high dose of n. caninum tachyzoites and temperature responses monitored daily for the first 2 weeks after inoculation. blood samples were collected before inoculation, and at regular intervals thereafter for 1 year. serological analysis was achieved using an indirect fluorescent antibody test (ifat), an enzyme-linked immunosorbent as ...200111182233
prevalence of neospora caninum antibodies in dogs from dairy cattle farms in parana, brazil.serum samples from 134 dogs from 22 cattle dairy farms in the northern region of parana state, brazil, were tested for antibodies to neospora caninum in an indirect fluorescent antibody test. antibodies (> or = 1:50) to n. caninum were found in 29 (21.6%) of the 134 dogs, and seropositive dogs were found on 14 (63.6%) of the 22 dairy cattle farrms. the antibody titers of dogs were 1:50 (3 dogs), 1:100 (7 dogs), 1:200 (7 dogs), 1:400 (6 dogs), and > or = 1:800 (6 dogs). the low prevalence (9%) in ...200212054023
epidemiological investigations of abortions due to neospora caninum on swiss dairy farms.abortions apparently due to neospora caninum in two swiss dairy herds were investigated by means of a pcr and elisa, and other potential causes were eliminated. in addition, a case-control study of 24 case herds and 24 control herds indicated that n caninum-associated abortions were more likely to occur in herds with antibodies to coxiella burnetii (with an odds ratio [or] of 3.38 with a 95 per cent confidence interval [ci] of 1.82 to 6.22), whereas the likelihood was less in herds with antibodi ...200212019533
a longitudinal study of neospora caninum infection on a dairy farm in new zealand.a 600-cow new zealand dairy herd experienced an abortion storm in 1997 and was monitored (blood sampling at about 3-month intervals) from may 1997 until january 1999. abortion risk reached 9% in 1997 and was highest in heifers at 19%. the abortion risk decreased in 1998 to 3.2% (still somewhat higher than during the years prior to the outbreak). the serological reaction pattern for neospora caninum showed an association with abortion risk only around the time of the 1997 outbreak when seropositi ...200212062516
characterization of neospora caninum surface protein ncsrs2 based on baculovirus expression system and its application for serodiagnosis of neospora infection.the baculovirus expression system has proved to be a useful tool for the production of recombinant proteins. here we have characterized the neospora caninum surface protein ncsrs2 produced by two types of the recombinant virus and also have developed an enzyme-linked immunosorbent assay (elisa) using recombinant ncsrs2 for the serologic diagnosis of neospora infection. western blot analysis showed two major protein bands that were detectable in insect cells infected with each recombinant baculov ...200111682519
validation of a commercially available monoclonal antibody-based competitive-inhibition enzyme-linked immunosorbent assay for detection of serum antibodies to neospora caninum in cattle.a previously described monoclonal antibody (mab)-based competitive-inhibition enzyme-linked immunosorbent assay (celisa) was modified to optimize performance, and the assay was validated in various defined cattle populations for detection of serum antibody to neospora caninum, a major cause of bovine abortion. modifications to the celisa included capturing native n. caninum antigen with a parasite-specific mab (mab 5b6-25) and directly conjugating the competitor mab (mab 4a4-2), with both mabs b ...200111682497
neospora caninum and waddlia chondrophila strain 2032/99 in a septic stillborn calf.characteristics of an intracellularly growing micro-organism isolated from an aborted bovine foetus are described. the organism replicated within cytoplasmic vacuoles, was resistant to penicillin and exhibited structural characteristics compatible with waddlia chondrophila. an elisa specific for chlamydia spp., immunofluorescence tests using antibodies directed against chlamydia spp. or simkania negevensis, and pcr using chlamydia-specific primers showed that the agent was distinct from chlamydi ...200211852195
neosporosis in a white rhinoceros (ceratotherium simum) calf.a 16-day-old white rhinoceros calf died suddenly while in excellent condition and showing no obvious previous clinical signs. it was the 9th calf of a mature female kept free-ranging with 11 other rhinoceros as well as various other game species on a 2000 hectare game breeding centre adjacent to the town of lichtenburg and outlying cattle farmlands in the northern province. at post mortem examination, death was ascribed to heart failure. there was marked multifocal to coalescing subacute parasit ...200212088073
vaccine development against neospora caninum infection.neospora caninum is a recognized protozoan parasite of a wide range of mammalian hosts, and was reported for the first time in 1988. the isolation of its oocysts in dog's faeces in 1998 led to its establishment as a parasitic species undergoing typical coccidian life cycle. infection with n. caninum causes paralysis and death in young livestock and companion animals, and is associated with abortions and stillbirth in cattle, and neurologic disease in calves. considering the economic and agricult ...200211853138
first confirmed case of neospora caninum-associated abortion outbreak in portugal.in a dairy herd experiencing an abortion outbreak, 49% of the 119 cows were positive for neospora caninum antibodies and the remaining 51% were seronegative. using immunohistochemical analysis of foetal brain tissue, neospora cysts and bradyzoite clusters were identified in two of the 15 aborted foetuses submitted for testing. other agents that commonly cause abortions were not found. these results, coupled with neurological clinical symptoms in new-born calves, implicated n. caninum as the majo ...200111928926
association between exposure to neospora caninum and milk production in dairy cows.to determine association between exposure to neospora caninum and milk production in dairy cows.200111549092
ranch-management factors associated with antibody seropositivity for neospora caninum in consignments of beef calves in texas, usa.a study was conducted with a 1998 retained-ownership population of texas (usa) beef calves to determine the ranch-management practices associated with calf seroprevalence to neospora caninum. management practices of 76 texas ranches that consigned 760 calves to a retained-ownership feedlot program were reviewed from a mailed questionnaire. ninety-nine of 760 (13%; 95% ci, 9.4%, 17.7%) calves were positive to n. caninum and 59% of the ranches consigned at least one positive calf. in the logistic ...200111566378
confirmation of the prevention of vertical transmission of neospora caninum in cattle by the use of embryo transfer. 200212224621
neospora then and now: prevalence of neospora caninum in maritime canada in 1979, 1989, and 1998.the seroprevalence of neospora caninum was compared among new brunswick, nova scotia, and prince edward island in 1998, 1989, and 1979. in 1998, the seroprevalence was lowest in prince edward island, where it was the same as in 1989. neospora caninum was present in 1979, but at a lower prevalence.200011126492
direct production losses and treatment costs from bovine viral diarrhoea virus, bovine leukosis virus, mycobacterium avium subspecies paratuberculosis, and neospora caninum.our purpose was to determine direct production losses (milk loss, premature voluntary culling and reduced slaughter value, mortaliy loss, and abortion and reproductive loss) and treatmetn costs (veterinary services, medication cost, and extra farm labour cost) due to four infectious diseases in the maritime provinces of canada: bovine viral diarrhoea (bvd), enzootic bovine leukosis (ebl), johne's disease (jd), and neosporosis. we used a partial-budget model, and incorporated risk and sensitivity ...200212350317
epidemiological pattern and risk factors associated with bovine viral-diarrhoea virus (bvdv) infection in a non-vaccinated dairy-cattle population from the asturias region of spain.a survey of bovine viral-diarrhoea virus (bvdv) infection was carried out in a non-vaccinated cattle population from the asturias region of spain in 1997 to assess seroprevalence and identify risk factors associated with infection. twenty-eight herds were included; 529 cows were bled. information regarding the herd and each animal sampled were recorded through a personal interview with the farmer. the true prevalence was estimated to be 21%. according to the antibody-age profiles and the herd-ma ...200111566379
prevalence of antibodies to neospora caninum in white-tailed deer, odocoileus virginianus, from the southeastern united states.serum samples from 305 white-tailed deer (odocoileus virginianus) from 14 states in the southeastern united states were examined for antibodies to neospora caninum using a direct agglutination test. positive agglutination titers were found in 145 (48%) of the white-tailed deer examined: 21 (7%) had titers of 1:25, 92 (30%) had titers of 1:50, and 32 (10%) had titers of > or = 1:500. these findings that antibodies to n. caninum are common in white-tailed deer support the concept that a sylvatic c ...200212054027
neospora caninum serostatus and milk production of holstein cattle.to determine whether neospora caninum serostatus was associated with milk production among holstein cattle in ontario.200212387387
protection against vertical transmission in bovine neosporosis.in this study we were interested to determine whether infection of cattle prior to pregnancy would afford any protection to the foetus if the dams were challenged with neospora caninum at mid-gestation. the experiment comprised four groups of cattle: group 1, uninfected controls; group 2, inoculated with n. caninum tachyzoites 6 weeks prior to mating and then challenged with n. caninum at mid-gestation; group 3, naive cattle challenged with n. caninum at mid-gestation and group 4 were infected w ...200111595240
a swiss case-control study to assess neospora caninum-associated bovine abortions by pcr, histopathology and serology.neospora caninum is one of the most frequent infectious organisms causing abortion in cattle worldwide. the present case-control study was designed to assess the importance of bovine neosporosis for causing abortion in swiss cattle and to identify selected risk factors. infection was primarily diagnosed by a n. caninum-specific pcr and serology, complemented with histopathology and immunohistochemistry. a total of 113 case and 113 corresponding control-farms were studied for 1.5 year. during thi ...200111705647
neosporosis in bovine dairy herds from the west of france: detection of neospora caninum dna in aborted fetuses, seroepidemiology of n. caninum in cattle and dogs.neospora caninum is considered one of the major causes of abortion in cattle in most parts of the world. in this study, the role of n. caninum was investigated in groups of aborted cattle and dairy herds from the west of france. good correlation was found between parasite dna detection in fetuses and serologic statuses of dams. in groups with documented abortion status and no antibodies to other pathogens, 17-45% of aborted animals were seropositive for n. caninum, and significant relationship b ...200111731070
in vitro antiprotozoal effects of artemisinin on neospora caninum.neospora caninum is an intracellular apicomplexan parasite that infects a wide range of mammals and has been associated with abortion in cattle worldwide. artemisinin is an effective antimalarial compound derived from a traditional chinese herbal remedy, qinghao or artemisia annua l. in the study reported, the cultured host cells (vero cells or mouse peritoneal macrophages) infected with n. caninum tachyzoites were incubated with alpha-mem (minimal essential medium) 10%hs supplemented with vario ...200211751000
neospora 2001.infection with the protozoan parasite neospora caninum is emerging as a major cause of reproductive loss in cattle worldwide. recent advances in research with the ultimate goal of devising effective and sustainable control measures were discussed at neospora 2001. neospora 2001 was held, 13-15 september 2001, at the moredun research institute, edinburgh, uk. the international meeting covered many aspects of bovine neosporosis including diagnosis, epidemiology and immunology.200211850000
first portuguese isolate of neospora caninum from an aborted fetus from a dairy herd with endemic neosporosis.neospora caninum was isolated from the brain of an aborted 4-month-old fetus from a dairy cow herd with endemic neosporosis in porto, portugal. the fetal brain homogenate was inoculated interperitoneally first into outbred swiss webster mice given dexamethasone and then the peritoneal exudates from these mice was co-inoculated with mouse sarcoma cells in the peritoneal cavity of mice given dexamethasone. n. caninum tachyzoites were seen in peritoneal exudate of the second passage. tachyzoites fr ...200212446085
seroprevalence of neospora caninum infection in dairy and beef cattle in paraguay.seroprevalence of neospora caninum in 879 beef and dairy cattle in different locations of paraguay was determined by an elisa. in the survey, 262 (29.8%) cattle were positive to n. caninum, and animals with anti-neospora antibody titre were observed in all the locations tested in the country. serum samples taken from a herd that exhibited persistent abortion had the highest percentage of animals being positive to the parasite (17/30, 56.7%). in the same herd, abortion was significantly more like ...200212446086
use of bulk milk for detection of neospora caninum infection in dairy herds in thailand.the relationship between the level of neospora caninum antibodies in bulk milk and the seroprevalence in lactating cows was investigated. bulk milk was also used to estimate the prevalence of n. caninum infection in dairy herds in the northeast and north thailand. bulk milk and individual serum from all lactating cows in 11 herds as well as 220 bulk milk samples from nine milk collection centres were analysed for presence of n. caninum antibodies using an iscom elisa. in the 11 herds the bulk mi ...200212446088
characterisation of the first australian isolate of neospora caninum from cattle.to isolate neospora caninum from a congenitally infected calf.200212465814
point source exposure of cattle to neospora caninum consistent with periods of common housing and feeding and related to the introduction of a dog.eight dairy herds with evidence of post-natal transmission of neospora caninum were used to test the hypothesis of a point source exposure by a retrospective analysis of the housing and feeding of infected age-groups. the first n. caninum-associated abortion or birth of n. caninum-seropositive offspring from the post-natally infected age-group was considered as the first indication of the infection. in seven of the eight dairy herds, a point source exposure to n. caninum of the infected age-grou ...200211900922
a method of probability diagnostic assignment that applies bayes theorem for use in serologic diagnostics, using an example of neospora caninum infection in cattle.to develop a method of probability diagnostic assignment (pda) that uses continuous serologic measures and infection prevalence to estimate the probability of an animal being infected, using neospora caninum as an example.200211911564
neospora caninum in persistently infected, pregnant cows: spontaneous transplacental infection is associated with an acute increase in maternal antibody.nine cows which were naturally and persistently infected with neospora caninum were housed and observed intensively throughout pregnancy. no recrudescence of a latent infection was detected by pcr tests on maternal blood but fetal infection, implying a recrudescence of maternal parasitosis, was associated with a marked increase in maternal antibody. the increase occurred in the second half of pregnancy in five cows which infected their calves, and before mid-pregnancy in one cow which aborted. t ...200111688746
risk of abortion associated with neospora caninum during different lactations and evidence of congenital transmission in dairy cows.to examine the relationship between exposure to neospora caninum and abortion in dairy cows during their first, second, third, and fourth or later lactations and to establish the main mode of transmission in female calves from birth until their first pregnancy was terminated by abortion or parturition.200212494973
diagnostic survey of bovine abortion in korea: with special emphasis on neospora caninum.causes of bovine abortion were surveyed in korea within a designated period from the cases submitted to the department of veterinary pathology, college of veterinary medicine, seoul national university. one hundred and eighty aborted fetuses and maternal sera were evaluated by necropsy, histopathology, bacteriology, virology, pcr, and serologic tests. the causes of abortion were identified in 108 (60%) cases, of which 38 (21.1%) were due to the infection with neospora caninum. none of the 38 cas ...200212520105
evaluation by different diagnostic techniques of bovine abortion associated with neospora caninum in spain.eighty foetuses from some of the main cattle-producing regions in spain were analysed to investigate the participation of neospora caninum in cases of bovine abortion. diagnosis of the infection was determined by histopathological analysis complemented with immunohistochemistry, serology (ifat and elisa) and pcr tests. a total of 38.8% of the bovine foetuses analysed were considered to be infected by at least one of the diagnostic techniques used. microscopic lesions consistent with neospora inf ...200312531290
factors associated with neospora caninum serostatus in cattle of 20 specialised costa rican dairy herds.twenty-five specialised costa rican dairy farms (located in the poás area) were used to determine neosporosis seroprevalence and the association of seropositivity with environmental and management factors. the farms involved were selected intentionally and all of them use vampp 5.1 (veterinary automated management and production control programme) as management-information system. holstein-friesian, jersey and crosses between them were the most-frequent breeds in these herds. the number of femal ...200211937233
fetal infection with neospora caninum in dairy and beef cattle in belgium.neospora caninum is a protozoan parasite, which causes fetal and neonatal mortality in livestock and companion animals. in 224 abortions in belgian cattle, different diagnostic methods were used to demonstrate infection, and the presence of n. caninum. an indirect fluorescent antibody test (ifat) was used to analyze fetal and maternal sera and immunohistochemistry (ihc) was performed when lesions consistent with neosporosis were observed in the brain, heart or liver. twenty dairy cattle sera out ...200212212893
immunological relationship between neospora caninum and besnoitia besnoiti.neospora caninum is a coccidian parasite identified as a major cause of abortion in cattle. a combined infection of n. caninum with another taxonomically related parasite of cattle, besnoitia besnoiti can occur in geographical areas endemic for both species. both infections are routinely diagnosed serologically, and incorrect diagnosis could occur if immunological cross-reactivity exists between the two parasites. to investigate the possible degree of cross-reactivity, we compared results obtain ...200211992709
quantitative detection of neospora caninum in bovine aborted fetuses and experimentally infected mice by real-time pcr.we report the development of a real-time pcr assay for the quantitative detection of neospora caninum in infected host tissues. the assay uses the double-stranded dna-binding dye sybr green i to continuously monitor product formation. oligonucleotide primers were designed to amplify a 76-bp dna fragment corresponding to the nc5 sequence of n. caninum. a similar method was developed to quantify the 28s rrna host gene in order to compare the parasite load of different samples and to correct for th ...200211923330
serological survey of neospora caninum infection in dairy cattle herds in aguascalientes, mexico.a serological survey for antibody activity to neospora caninum was carried out in aguascalientes, a state in the central part of mexico. one-hundred and eighty-seven serum samples from 13 dairy herds were tested by the elisa test. the herd prevalence was 100% and the overall prevalence was 59% (n=110). seventy-six of 97 seropositive cows had previous records of abortion. there was a statistically significant difference between the groups (p<0.05). however, the odds ratio was 1.4, suggesting an a ...200212031815
occurrence of neospora caninum antibodies in sera from dogs of the city of são paulo, brazil.neospora caninum is an important cause of abortion in dairy cattle worldwide. dogs are important in the epidemiology of this parasite because they are the only hosts known to excrete n. caninum oocysts. in order to understand the prevalence of n. caninum in dogs, sera from 500 owned dogs and from over 600 feral street dogs from the city of são paulo, brazil were assayed for antibodies to n. caninum. sera were examined by the neospora agglutination test (nat) using mouse-derived tachyzoites. anti ...200212031819
pattern of recognition of neospora caninum tachyzoite antigens by naturally infected pregnant cattle and aborted foetuses.different aspects of neospora tachyzoite antigen recognition by neospora-infected heifers and cows and aborted foetuses were studied. the pattern of antigen recognition and the relationship between ifat titres and number of neospora antigens detected, were evaluated. in addition, the tachyzoite antigens involved in the humoral immune response developed against infection in normal cows and cows that aborted were also characterised throughout pregnancy. comparison of tachyzoite antigen recognition ...200212072210
redescription of neospora caninum and its differentiation from related coccidia.neospora caninum is a protozoan parasite of animals, which before 1984 was misidentified as toxoplasma gondii. infection by this parasite is a major cause of abortion in cattle and causes paralysis in dogs. since the original description of n. caninum in 1988, considerable progress has been made in the understanding of its life cycle, biology, genetics and diagnosis. in this article, the authors redescribe the parasite, distinguish it from related coccidia, and provide accession numbers to its t ...200212076623
p38-avidity-elisa: examination of herds experiencing epidemic or endemic neospora caninum-associated bovine abortion.an enzyme-linked immunosorbent assay (elisa) was established to measure the avidity of bovine igg directed against p38, a surface antigen (ncsrs2) of neospora caninum tachyzoites. in the sera of dams intravenously infected with n. caninum nc-1, the p38-specific avidity increased from initially below 40% up to avidity indices between 50 and 80% after days 23 and 91 p.i. the p38-avidity-elisa was used to examine various herds that had experienced endemic and epidemic n. caninum-associated bovine a ...200212079735
determination of antigenic domain in gst fused major surface protein (nc-p43) of neospora caninum.the antigenic domain of the major surface protein (nc-p43) of neospora caninum was examined by polymerase chain reaction of its gene fragments and recombinant expression as gst fusion proteins. the fragments of nc-p43 were as follow: a total open reading frame (ofr), t; ofr without signal sequence and c-terminal hydrophobic sequence, s; n-terminal 2/3 parts of s, a; c-terminal 2/3 parts, p; n-terminal 1/3 part, x; middle 1/3 part, y; and c-terminal 1/3 part, z, respectively. the dna fragments we ...200111590914
serological diagnosis of neosporosis in a herd of dairy cattle in southern brazil.neospora caninum-specific antibodies were detected in 60 of 172 (34.8%) dairy cattle by enzyme-linked immunosorbent assay (elisa) in a herd from parana state, brazil. the seropositive animals included 47 of 126 (37.3%) adult cows, 7 of 29 (24%) heifers (1-2 yr), 4 of 15 (27%) heifers (5 mo-1 yr), and 2 precolostral samples. data collected over a 9-yr follow-up period revealed that the proportion of pregnancies ending in abortion was 20% (31/154) among elisa seropositive cows and 8% (15/193) amon ...200111780849
coprodiagnosis of hammondia heydorni in dogs by pcr based amplification of its 1 rrna: differentiation from morphologically indistinguishable oocysts of neospora caninum.hammondia heydorni is thought to be a non-pathogenic coccidian parasite of dogs that is closely related to neospora caninum, an important parasite of cattle and dogs. oocysts of these two species are morphologically indistinguishable from each other. a population of 2240 dogs in the czech republic was screened for the presence of h. heydorni/n. caninum oocysts and five (0.22%), represented by five of 3135 faecal samples (0.16%), were positive. the internal transcribed spacer 1 region of the rrna ...200212093189
an analysis of the performance characteristics of serological tests for the diagnosis of neospora caninum infection in cattle.to analyse the performance characteristics (sensitivity/specificity) of two enzyme-linked immunosorbent assays (elisa) against the indirect fluorescent antibody test (ifat).200212127250
small-subunit rdna sequencing of the italian bovine neospora caninum isolate (nc-pv1 strain).the small-subunit (ssu) rdna of the neospora sp. nc-pv1 strain isolated in italy from cattle has been sequenced and compared to the other five n. caninum strains ssu rdna sequences deposited in the data bases. the nc-pv1 strain sequence is identical to three published sequences. minor differences, respectively four nucleotide bases and one nucleotide base, have been found when comparing the nc-pv1 sequence with two other available sequences of n. caninum. according to these results, the neospora ...200011686077
neospora caninum: oocyst challenge of pregnant cows.three pregnant cows were each orally challenged at 10 weeks of gestation with 600 sporulated oocysts of neospora caninum. the number of oocysts was limited by those available. in concurrent bioassays, one oocyst per os infected each of two gerbils. challenged cattle developed neospora-specific antibody, cell proliferation and gamma-interferon responses. n. caninum specific pcr demonstrated persisting infection in the brains of cows 4 months after calving. abortion was not induced and there was n ...200212383634
neospora caninum-infected cattle develop parasite-specific cd4+ cytotoxic t lymphocytes.cattle infected with neospora caninum readily experience transplacental parasite transmission, presumably after maternal parasitemia, leading to abortion or birth of congenitally infected calves. cytotoxic t lymphocytes (ctl) are important mediators of protective immunity against toxoplasma gondii, an intracellular apicomplexan protozoan closely related to n. caninum. in this study, n. caninum-specific ctl expanded from peripheral blood mononuclear cells of two major histocompatibility complex-m ...200312761108
survey of neospora caninum antibodies in dairy and beef cattle from five regions of the united states.serum samples from 4,907 cows from 93 dairy and five beef herds were analyzed for antibodies to neospora caninum by commercially available elisa. the herds were recruited from 20 states and the territory of puerto rico. a questionnaire assessed the herd's abortion history and exposure risks to n. caninum. results showed that 788 (16%) cows tested positive for antibodies to n. caninum. at least one positive animal was detected in 90% of the herds tested. the prevalence of cows seropositive to n. ...200212584676
serological evidence of neospora caninum infections in beef bulls in six counties of the corrientes province, argentina.the purpose of the present work was to identify neospora caninum infections in beef bulls belonging to 19 herds from six counties located in the corrientes province, argentina. the presence of antibodies to n. caninum was evaluated in 305 serum samples of bulls (bos taurus and bos indicus). age and breed were recorded. an indirect fluorescent antibody test was used to determine specific antibodies. the number of bulls with natural neospora-infection was 15 of 305 (4.9%). no association between s ...200312809751
prevalence of antibodies to neospora caninum in dogs from amazon, brazil.neospora caninum is an important cause of abortion in dairy cattle worldwide. dogs are important in the epidemiology of this parasite because they are the only hosts known to excrete n. caninum oocysts. antibodies to n. caninum were assayed in serum samples from 157 dogs from monte negro, rondônia, amazon, brazil using the indirect fluorescent antibody test. antibodies to n. caninum were found in 13 (8.3%) of dogs in titers of 1:50 in 1, 1:100 in 2, 1:200 in 5, 1:800 in 1, 1:1600 in 2, and 1:320 ...200312860070
validation of 2 commercial neospora caninum antibody enzyme linked immunosorbent assays.this is a validation study of 2 commercially available enzyme linked immunosorbent assays (elisa) for the detection of antibodies against neospora caninum in bovine serum. the results of the reference sera (n = 30) and field sera from an infected beef herd (n = 150) were tested by both elisas and the results were compared statistically. when the immunoblotting results of the reference bovine sera were compared to the elisa results, the same identity score (96.67%) and kappa values (k) (0.93) wer ...200212418782
prevalence of antibodies to neospora caninum in korean native beef cattle.a total of 438 sera from korean native beef cattle in 9 provinces were tested for neospora caninum antibodies using an immunofluorescent antibody test (ifat). eighteen (4.1%) cattle were positive by ifat. the titers ranged from 1:200 (10 animals), 1:400 (5 animals), 1:800 (2 animals) to 1:1,600 (1 animal). although the seroprevalence was slightly higher in chungnam (8.9%), this was not significantly different from those noted in kyunggi, kangwon, kyungbuk, kyungnam, and cheju provinces. sera obt ...200212419873
a high rate of seroconversion for neospora caninum in a dairy herd without an obvious increased incidence of abortions.the purpose of this paper is to investigate the high rate of seroconversion for neospora caninum in a dairy herd. forty-five of 95 (47%) of the seronegative animals seroconverted within a period of 6 months. seropositive animals were not equally distributed among age-groups. a high seroprevalence age-group of 8-30 months was housed together during a period of 4 months, indicating a point source infection within this period. a lack of association between the serological status of daughters and mo ...200212423933
an explorative study to assess the efficacy of toltrazuril-sulfone (ponazuril) in calves experimentally infected with neospora caninum.neospora caninum is an important cause of infectious abortion and stillbirth in cattle world-wide. infection is common and may frequently be passed from mother to calf (vertical transmission) with no signs of disease. based on our previous observation that n. caninum-infection can be efficiently controlled with toltrazuril-sulfone (ponazuril) in experimentally infected mice, we addressed the question if efficacy could also be obtained in experimentally infected calves.200212437777
immune responses to neospora caninum and prospects for vaccination.developing an effective vaccine against neosporosis presents several interesting challenges. the parasite is spread efficiently from mother to foetus over several generations, and naturally infected cattle do not appear to develop adequate protective immunity. modulation of the immune response during pregnancy favours parasite survival and multiplication. however, induction of pro-inflammatory responses that are thought to be protective against neospora caninum would be detrimental to the pregna ...200212473366
management factors related to seroprevalences to bovine viral-diarrhoea virus, bovine-leukosis virus, mycobacterium avium subspecies paratuberculosis, and neospora caninum in dairy herds in the canadian maritimes.bovine viral-diarrhoea (bvd), enzootic bovine leukosis (ebl), johne's disease (jd), and neosporosis lower on-farm productivity, reduce export competitiveness, and increase consumer concerns regarding safety. our purpose was to examine the relationship between 27 control practices and the estimated true seroprevalences for these four diseases for 2604 cattle in 90 dairy herds in the maritimes provinces of canada. overall, 37.8, 20.4, 3.4, and 19.2% of all sampled cattle were truly exposed to the ...200212324207
aetiology of bovine abortion in argentina.necropsies were performed on 354 fetuses from dairy and beef herds submitted from 1994 to 2000 to the diagnostic laboratories at instituto nacional de tecnología agropecuaria, balcarce, argentina. samples from the fetuses were examined for pathogenic organisms and processed for microscopic examination. an aetiological diagnosis was made for 161 (45.5%) of the fetuses. no diagnosis was made for 193 (54.5%) fetuses. infectious agents were isolated from 122 (34.4%) of the fetuses, bacterial agents ...200314509450
seroepidemiology of beef and dairy herds and fetal study of neospora caninum in argentina.the purpose of the present work was to study the epidemiology of neospora caninum in beef and dairy herds in the humid pampas of argentina. the seroprevalence of n. caninum was evaluated in 2414 serum samples of cows from beef and dairy farms. an indirect fluorescent antibody test (ifat) was used to determine specific antibodies. the sera was screened at a dilution >or=1:200 and >or=1:600 in cows with reproductive disease antecedents and without them, respectively. cows without history of reprod ...200212163242
humoral immune response to infectious agents in aborted bovine fetuses in argentina.the purpose of this study was to characterize the exposure of bovine aborted fetuses from beef and dairy herds of the humid pampas of argentina to different infectious agents by the evaluation of fetal fluid antibodies. presence of fetal antibodies to bovine viral diarrhea virus genotype 1 (bvdv-1), bovine herpes virus type 1 (bhv-1), leptospira interrogans, brucella abortus, and neospora caninum was determined. of the 95 fetuses processed, 66 came from 49 beef herds and 29 from 12 dairy herds. ...200314587376
reproductive losses due to neospora caninum in a beef herd in argentina.reproductive losses in a beef herd of 857 heifers with a pregnancy rate of 86.3% are described. after pregnancy testing, 69 abortions were seen during a 3 month period. before calving season, three heifers had delivered pre-mature non-viable calves. serum samples from 58 of 69 aborted heifers were available for serological tests. in order to compare the seroprevalence in non-aborted vs. aborted heifers, 214 pregnant animals were bleed during the abortion storm. in addition, blood samples were co ...200314629003
assessment of antibody avidity in aborting cattle by a somatic neospora caninum tachyzoite antigen igg avidity elisa.a neospora caninum igg avidity elisa was carried out on the basis of a somatic n. caninum tachyzoite antigen. the test was validated using experimentally infected calves, where a clear maturation of the igg avidity over time could be demonstrated. at a maximum of 82 days after infection (d.p.i.), all animals showed antibody avidities ranging above 35%, and respective sera were thus defined as highly avid. sera of 103 naturally infected seropositive cows with abortion (n. caninum association was ...200312581580
neospora caninum infection and congenital transmission: serological and parasitological study of cows up to the fourth gestation.in this paper, a parasitological and serological study performed in three cows up to the fourth gestation is reported in order to clarify the extent of vertical propagation and, secondly, in which period of gestation the recrudescence of previous infection occurs. the cows selected for the study delivered healthy but congenitally infected calves in first pregnancy. the parasite was found, by biological tests in swiss mice, in all the placentas of the three cows examined, during the three subsequ ...200314633211
regional distribution of bovine neospora caninum infection in the german state of rhineland-palatinate modelled by logistic regression.to obtain a rapid overview over the distribution of bovine neospora caninum-infections in the german state of rhineland-palatinate, an elisa to determine specific bovine antibodies against a p38 surface antigen of n. caninum tachyzoites was modified to examine bulk milk samples from cattle herds. experimental bulk milk samples were used to demonstrate that the seroprevalence in a group of animals can be estimated with this elisa. a cut-off was selected for the specific detection of herds having ...200314636679
validation of a neospora caninum iscom elisa without a gold standard.neospora caninum is an intracellular parasite which causes abortion in cattle worldwide. one problem in the validation of the different methods for demonstration of this parasite is the lack of an appropriate gold standard. to validate an immunostimulating complex (iscom) enzyme-linked immunoassay (elisa) used to detect antibodies to n. caninum, sera from 244 cattle in five swedish dairy herds infected with n. caninum were analysed. the sera also were analysed by a standard indirect-fluorescent ...200312581597
abortion epidemic in a dairy herd associated with horizontally transmitted neospora caninum infection.a dairy herd experienced an abortion epidemic during which 43 per cent of the cows at risk aborted. neospora caninum infection was demonstrated in four of six fetuses suitable for examination and the group of at-risk cows that aborted had significantly higher n. caninum antibody concentrations than the at-risk cows that delivered a live calf at term (p<0.001). the antibody concentrations in the cow herd were significantly higher than in the youngstock (p<0.001), and the concentrations in the you ...200312620035
neosporosis in mexican dairy herds: lesions and immunohistochemical detection of neospora caninum in fetuses.of 211 aborted bovine fetuses collected from mexican dairy herds between january 1996 and march 1999, 73 showed microscopical lesions consistent with neosporosis. of these 73 fetuses, 58 (79%) showed lymphocytic myocarditis, 39 (53%) showed microgliosis and multifocal necrosis in the brain, 39 (53%) showed lymphocytic hepatitis, and 19 (26%) showed lymphocytic myositis. immunohistochemical examination of brain, myocardium and liver from 53 of the same 73 fetuses demonstrated neospora caninum ant ...200111437517
neospora caninum antigens recognized by mouse igg at different stages of infection including recrudescence.western blotting was performed to analyze neospora caninum tachyzoite antigens recognized by mouse igg at different stages of infection including recrudescence. at the early stage of infection, a 36-38 kda antigen was clearly recognized by the mouse antisera. after day 48 postinoculation, the signal of the 36-38 kda antigen gradually weakened. meanwhile, a 43 kda antigen was intensely and continuously recognized from 48 to 125 days postinoculation. this 43 kda antigen was clearly detectable with ...200312867739
evaluation of an inactivated neospora caninum vaccine in beef feedlot steers.to evaluate effects of vaccination of feedlot steers against bovine neosporosis on weight gain, feed intake and efficiency (feed intake per gain), and carcass characteristics.200312619843
a hammondia-like parasite from the european fox (vulpes vulpes) forms biologically viable tissue cysts in cell culture.tissue cysts of parasites of the genus hammondia are rarely described in naturally or experimentally infected intermediate hosts. however, ultrastructural examinations on tissue cyst stages of hammondia sp. are needed, e.g. to compare these stages with those of neospora caninum and other related parasites. we describe a cell culture system employed to examine the in vitro development of tissue cysts of a hammondia sp.-like parasite (isolate fox 2000/1) which uses the european fox as a definitive ...200312670509
infection by neospora caninum associated with bovine herpesvirus 1 and bovine viral diarrhea virus in cattle from minas gerais state, brazil.neospora caninum is a canine parasite which is considered a significant cause of bovine abortion. two cattle herd groups were serologically studied with the objective of studying the prevalence of infection by n. caninum associated with bhv1 and bvdv infections. in group i, 15 dairy herds (476 samples) naturally infected by the three infectious agents were analyzed,. in group ii, three dairy herds (100 samples) of cows vaccinated for two viruses were analyzed, in order to determine the infection ...200414746970
application of the neospora caninum igg avidity elisa in assessment of chronic reproductive losses after an outbreak of neosporosis in a herd of beef cattle.point-source infections are most likely the cause for neospora caninum-induced abortion outbreaks in cattle, whereas an increased annual abortion rate may be a consequence of vertical transmission. the aims of the present study were to examine the reproductive effects of neosporosis in a beef herd for 3 years, after a point-source outbreak and to use igg avidity serology to examine the chronicity of infections and patterns of transmission. during the study, 76-78% of animals were seropositive fo ...200312580287
comparison and standardisation of serological methods for the diagnosis of neospora caninum infection in bovines.various existing serological tests were compared with a standard panel of 523 sera in a multicentred study across europe. well characterised sera from animals that were experimentally or naturally infected with neospora caninum as well as sera from cattle deemed uninfected with n. caninum were provided by the participants of the study and analysed in several commercial (chekit dr. bommeli/intervet, civtest bovis neospora hipra, cypress diagnostics c.v., herd check idexx, mastazyme mast diagnosti ...200415019139
isolation of viable toxoplasma gondii from naturally infected aborted bovine fetuses.neospora caninum and toxoplasma gondii are related parasites. the former is a common cause of abortion in dairy cattle. the latter has not been conclusively demonstrated in bovine fetuses. during the course of attempts to isolate n. caninum from aborted fetuses, t. gondii was isolated from 2 aborted fetuses, 1 from portugal and 1 from the united states. both isolates were made by bioassay of fetal brains in mice. the fetus from portugal was about 5 mo in gestational age, and the fetus from the u ...200212537120
determination and correlation of anti-neospora caninum antibodies in dogs and cattle from mexico.the aim of the present study was to determine and to compare through an indirect enzyme linked immunosorbent assay (elisa) test, the presence of anti-neospora caninum antibodies in city and farm dogs, as well as in farm cows, and the relationship among them. the correlation between anti-n. caninum antibodies in farm dogs and cattle was also assessed. the research was conducted in the dairy region of tizayuca, hidalgo, mexico. the frequency of anti-n. caninum antibodies was significantly higher i ...200312760481
improved production of neospora caninum oocysts, cyclical oral transmission between dogs and cattle, and in vitro isolation from oocysts.scarce information is available about neospora caninum oocysts and sporozoites, in part because only small numbers of oocysts have typically been produced by experimentally infected dogs. we hypothesized that i reason for low experimental production of oocysts is that dogs have been fed tissues from experimentally infected mice instead of tissues from cattle (which are natural intermediate hosts of n. caninum). in this study, 9 dogs were fed tissues from n. caninum-infected calves, and oocyst pr ...200212537111
seroprevalence and associated risk factors of neosporosis in beef and dairy cattle in italy.a cross-sectional serological survey for neospora caninum was carried out on beef and dairy cattle in southern and northern italy. a total of 111 herds and 1140 animals were tested using an elisa assay (chekit-neospora) to detect anti-n. caninum antibodies. management and individual data were collected and analysed both by linear and logistic multiple-regression models in order to find good predictors of the cattle seroprevalence and anti-n. caninum antibody level. at least one seropositive anim ...200314651870
neospora caninum in vitro: evidence that the destiny of a parasitophorous vacuole depends on the phenotype of the progenitor zoite.we previously reported that neospora caninum can be induced to express bagi, a bradyzoite antigen, within 3 days of culture under stress conditions. the main goals of the present experiment were to increase the expression of bagi in vitro (in part by extending cultures for 9 days), to observe parasitophorous vacuoles at various points of stage differentiation, and to test the ability of organisms produced in vitro to function like mature bradyzoites. expression of bag1 and of a tachyzoite antige ...200212537100
prevalence of antibodies to neospora caninum within central queensland beef cattle. 200315080432
serological status and abortion rate in progeny obtained by natural service or embryo transfer from neospora caninum-seropositive cows.bovine neosporosis is an important disease in dairy herds in argentina. embryo transfer (et) technology offers the opportunity to minimize vertical transmission of neosporosis. the objective of this work was to compare the serological status and the incidence of abortion between heifers obtained via natural service and heifers obtained by et from neospora-infected cows. progeny from eight neospora-infected cows belonging to a commercial dairy farm where et was routinely performed were studied. b ...200314633201
an abortion storm in cattle associated with neosporosis in taiwan.an abortion storm associated with acute neosporosis involving 18 cattle was observed in a dairy farm in taiwan. aborted fetus age ranged from 3 to 8 months. of the 38 cattle in that farm examined during the abortion storm, 52.6% (20/38), 13.2% (5/38) and 10.5% (4/38) contained both igg and igm, only igg and only igm antibodies to neospora caninum, respectively. no antibody to n. caninum was detected prior to the abortion storm. follow-up study conducted a year later showed that 23 out of 28 catt ...200415133282
neospora caninum serostatus and culling of holstein cattle.to determine whether time until culling or risk of culling was associated with neospora caninum serostatus among holstein cattle in dairy herds in ontario.200212387388
economic considerations for diagnostic and control options for neospora caninum-induced abortions in endemically infected herds of beef cattle.to compare economic outcome for herds not exposed to neospora caninum with that for herds with various seroprevalences of n caninum infection and evaluate 3 control strategies.200415154728
neospora caninum: a cause of immune-mediated failure of pregnancy?resistance to many intracellular protozoan parasites is dependent on t helper cell 1 cytokine responses. this has important repercussions for pregnant females because strong t helper cell 1 cytokine responses are incompatible with successful pregnancy. thus, there are two possible consequences of infection with protozoans such as leishmania major, plasmodium falciparum and toxoplasma gondii during pregnancy: (1) pregnancy is compromised; or (2) resistance to the parasite is compromised. the apic ...200212377255
investigation of neospora sp. antibodies in aborted mares from normandy, france.neospora caninum, an apicomplexan protozoan parasite, is recognized as a major cause of abortion in cattle while limited information is presently available on association between equine neospora infections and abortions. the aim of the present study was to document prevalence of antibodies against neospora sp. in aborted mares as a clue to the role of n. caninum in mare reproductive failure in normandy, france. using an agglutination test, the number of animals with elevated (>80) anti-neospora ...200314651869
anti-parasitic activity of depudecin on neospora caninum via the inhibition of histone deacetylase.neospora caninum is an apicomplexan parasite associated with abortion in cattle worldwide. apicidin, histone deacetylase (hdac) inhibitor, has shown a broad spectrum of anti-protozoal activity against apicomplexan parasites. cultured vero cells infected with n. caninum tachyzoites were treated with 0.5 microg/ml of depudecin, another known natural product isolated from altermaria brassiciicola with anti-histone deacetylase activity, to examine the efficacy of depudecin against intracellular mult ...200312623206
additional evaluation of undiagnosed bovine abortion cases may reveal fetal neosporosis.diagnosis of neospora caninum associated bovine abortion is often made by histological examination of fetal tissues, although this procedure is not very sensitive. one hundred and forty-four undiagnosed bovine abortion cases were evaluated for n. caninum associated bovine abortion using a revised diagnostic protocol. as a result, 12 (8.3%) of these previously undiagnosed bovine abortion cases were definitively diagnosed as n. caninum positive. the 12 new positive cases included 7 that had exhibi ...200312651213
evaluation of a single serological screening of dairy herds for neospora caninum antibodies.twenty-one dairy herds with a history of neospora caninum-associated abortions were used for a longitudinal serological study. a total of 1,676 animals were blood sampled 3 times and used to evaluate a single serological screening for n. caninum antibodies. the results of the first serological screening were compared with the results based on three consecutive samples, whereby two or more positive or negative test results per animal were considered to determine its serological status as positive ...200312482645
elisa detection of igg antibody against a recombinant major surface antigen (nc-p43) fragment of neospora caninum in bovine sera.an elisa was established to measure bovine igg directed against the recombinant antigenic determinant of nc-p43, a major surface antigen of neospora caninum. in a previous study, two thirds of the c-terminal of the molecule was expressed as a 6 x his tagged protein (ncp43p) for elisa using 2/3 of the n-terminal of sag1 from toxoplasma gondii as a control (tgsag1a). among 852 cattle sera collected from stock farms scattered nation-wide, 103 sera (12.1%) were found to react with ncp43p positively, ...200312972732
finding of neospora caninum in the wild brown rat (rattus norvegicus).nine rats (16.4%) out of 55 (rattus norvegicus) from cattle farms were seropositive to neospora caninum. two of the seropositive rats were also pcr positive but all were negative by immunohistochemistry and pas staining. the brains of all the captured rats were homogenized and initially inoculated intraperitoneally into nude mice or into spf icr mice, which had been immunosuppressed with prednisolone. one mouse that was inoculated with brain material from a seropositive rat became infected with ...200415210077
maternal and fetal immune responses of cattle inoculated with neospora caninum at mid-gestation.the humoral and cell-mediated immune responses of pregnant cattle and their fetuses were examined at intervals after infection with neospora caninum tachyzoites at mid-gestation (day 140). all cattle seroconverted and interferon gamma was detected in supernatants of peripheral blood mononuclear cells stimulated with specific antigen. at day 14 post-inoculation (pi), specific cell proliferation responses were detected in the lymph node draining the site of inoculation and in the uterine lymph nod ...200415003463
[the importance of bovine neosporosis for abortion in switzerland].the protozoan parasite neospora caninum is one of the most important infectious abortion causes in cattle worldwide. in a swiss case-control-study we investigated 113 abortion problem farms and 113 control farms. it was possible to detect n. caninum in 21% of 242 investigated aborted fetuses by pcr upon brain samples. eighty-four % of mothers aborting n. caninum positive fetuses were serologically positive for this parasite. the seroprevalence for n. caninum of all aborting mothers was 44%. with ...200312677771
determination of the seroprevalence of neospora caninum in feedlot steers in alberta.a study was conducted in alberta to determine the seroprevalence of neospora caninum in feedlot calves purchased from various auction markets throughout western canada. four feedlots (1 feedlot from each of the airdrie and high river areas and 2 feedlots from the strathmore area) were selected for sampling. at each feedlot, a random 10% sample of feedlot steer and bull calves entering the feedlot from september 2001 to december 2001 were enrolled in the study until there were a maximum of 500 an ...200415072193
the cell-mediated immune response to neospora caninum during pregnancy in the mouse is associated with a bias towards production of interleukin-4.neospora caninum is an obligate intracellular protozoan parasite which is efficiently transmitted transplacentally in cattle where it may cause abortion. a pregnant mouse model was used to characterise the immune response following n. caninum infection; the response in non-pregnant and pregnant mice was compared. spleen cells from both infected/non-pregnant and infected/pregnant mice produced interferon-gamma, interleukin-12 and tumour necrosis factor alpha; however, the levels of these th1 cyto ...200415111094
detection of neospora caninum in an aborted goat foetus.in italy neospora caninum has been reported in cattle, in buffaloes and in dogs. no data are available about the infection in sheep and goats. in this paper, the authors report the detection of protozoan cysts, identified as n. caninum by pcr, in the brain of an aborted goat foetus.200415325053
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