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
characterization of neospora caninum protease, ncsub1 (nc-p65), with rabbit anti-n54.ncsub1 (formerly known as nc-p65) is the first molecularly described proteolytic enzyme of the intracellular protozoan parasite neospora caninum. this report describes the characterization of a rabbit anti-n54, which is an antiserum generated against an internal fragment of ncsub1 (amino acids 649-783). in immunofluorescence studies rabbit and-n54 labeled the apical end of the fixed parasite. by immuno-gold electron microscopy, the antibody bound primarily to the microneme organelles of the para ...200212537103
experimental infection of sheep with neospora caninum oocysts.the purpose of the present study was to investigate the potential of neospora caninum oocysts to infect sheep and determine whether n. caninum dna could be detected by polymerase chain reaction (pcr) assay in blood and brain of sheep after oocyst inoculation. six ewes were inoculated per os with 10(4) n. caninum oocysts, whereas 2 ewes served as uninoculated controls. all sheep were bled weekly for 7 wk after inoculation. blood was analyzed for the presence of n. caninum dna by 2 different pcr a ...200212537104
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
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
prevalence of antibodies to neospora caninum and sarcocystis neurona in sera of domestic cats from brazil.parasite biology, epidemiology and systematics laboratory, animal and natural resources institute, agricultural research service, united states department of agriculture, building 1001, beltsville, maryland 20705-2350 antibodies to neospora caninum and sarcocystis neurona were determined in serum samples of 502 domestic cats from brazil using direct agglutination tests with the respective antigens. antibodies to s. neurona were not found in 1:50 dilution of any serum in the s. neurona agglutinat ...200212537122
seroprevalence of antibodies to neospora caninum in dogs from spain.the prevalence of neospora caninum antibodies was determined in sera of 139 dogs from catalonia (northeastern spain) using the indirect immunofluorescence antibody test (ifat). antibodies in the ifat were found in 17 of 139 dogs (12.2%) with titers ranging from 1:50 to 1: 1,600. seroprevalence was higher in dogs over 1 yr old compared with dogs younger than 1 yr (p < 0.05). no statistical difference was observed when sex, breed, purpose, or modus vivendi was compared with seropositivity. most do ...200212537126
[progress in the research on the tachyzoite-bradyzoite conversion of toxoplasma gondii]. 200012567672
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
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
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
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
gene discovery in the apicomplexa as revealed by est sequencing and assembly of a comparative gene database.large-scale est sequencing projects for several important parasites within the phylum apicomplexa were undertaken for the purpose of gene discovery. included were several parasites of medical importance (plasmodium falciparum, toxoplasma gondii) and others of veterinary importance (eimeria tenella, sarcocystis neurona, and neospora caninum). a total of 55192 ests, deposited into dbest/genbank, were included in the analyses. the resulting sequences have been clustered into nonredundant gene assem ...200312618375
evaluation of an inactivated neospora caninum vaccine in beef feedlot 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
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
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
reduced cerebral infection of neospora caninum-infected mice after vaccination with recombinant microneme protein ncmic3 and ribi adjuvant.c57bl/6 mice were vaccinated with a bacterially expressed and purified polyhistidine-tagged full-length version of the microneme protein ncmic3 (recncmic3) emulsified in ribi adjuvant system (ras). subsequently, they were challenged by intraperitoneal inoculation of 2 x 10(6) live neospora caninum tachyzoites. as controls, groups of mice received phosphate-buffered saline (pbs)-ras alone (adjuvant control) or were treated with pbs before infection (infection control). the protective effect of va ...200312659301
review of neospora caninum and neosporosis in animals.neospora caninum is a coccidian parasite of animals. it is a major pathogen for cattle and dogs and it occasionally causes clinical infections in horses, goats, sheep, and deer. domestic dogs are the only known definitive hosts for n. caninum. it is one of the most efficiently transmitted parasite of cattle and up to 90% of cattle in some herds are infected. transplacental transmission is considered the major route of transmission of n. caninum in cattle. neospora caninum is a major cause of abo ...200312666725
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
[abortion in small ruminants in switzerland: investigations during two lambing seasons (1996-1998) with special regard to chlamydial abortions].abortion cases of 144 goats und 86 sheep were investigated etiologically during 2 lambing seasons (1996/1997, 1997/1998). macroscopic inspection of fetus and placenta was completed by histopathology and bacteriological isolation of agents. in addition, immunohistologically the following antigens were labeled in formalin-fixed and paraffin-embedded tissue sections: toxoplasma gondii, neospora caninum, chlamydophila abortus (formerly chlamydia psittaci serovar 1) and border disease virus. from far ...200212677687
[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
susceptibility of djungarian hamsters (phodopus sungorus) to neospora caninum infection.djungarian hamsters were examined for the susceptibility to neospora caninum infection. after 29 djungarian hamsters were intraperitoneally inoculated with 5 x 10(6) n. caninum tachyzoites of jpa1 strain, some animals showed symptoms such as ataxia, and many tissue cysts were detected in the brain and a cyst in the muscular tunics of stomach. especially, more than 100 cysts per head were observed after 5 weeks post inoculation. it is suggested that the djungarian hamster is a model useful to exa ...200312679575
vaccination of ewes for prevention of vertical transmission of neospora evaluate the immunologic response of a killed tachyzoite vaccine against neospora caninum and its effectiveness in preventing vertical transmission of n caninum in sheep.200312693535
first pcr-confirmed report of a neospora caninum-associated bovine abortion in austria. 200312723631
vaccination of mice against experimental neospora caninum infection using ncsag1- and ncsrs2-based recombinant antigens and dna vaccines.ncsag1 and ncsrs2, the two major immunodominant tachyzoite surface antigens of the apicomplexan parasite neospora caninum, were investigated for their potential as vaccine candidates in mice. recombinant recncsrs2 and recncsag1 were expressed in escherichia coli as poly-histidine-tagged fusion proteins. separate groups of mice were immunized with purified recncsag1, recncsrs2, or a combination of both, and were then challenged with n. caninum tachyzoites. subsequent experiments included intramus ...200312741509
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
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
the effect of the dam-calf relationship on serostatus to neospora caninum on 20 costa rican dairy epidemiological study was conducted on 20 dairy herds previously diagnosed as seropositive for neospora caninum. the number of females per farm varies from 41 to 296. all females present on the farms were bled once in the period of july and august 2000. a total of 3002 females were bled. an indirect elisa was used to determine the serostatus of the animals. the analysis of the data was performed in four steps: (1) descriptive statistics about the serological status and general characteristics ...200312788252
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
analysis of the sarcocystis neurona microneme protein snmic10: protein characteristics and expression during intracellular development.sarcocystis neurona, an apicomplexan parasite, is the primary causative agent of equine protozoal myeloencephalitis. like other members of the apicomplexa, s. neurona zoites possess secretory organelles that contain proteins necessary for host cell invasion and intracellular survival. from a collection of s. neurona expressed sequence tags, we identified a sequence encoding a putative microneme protein based on similarity to toxoplasma gondii mic10 (tgmic10). pairwise sequence alignments of snmi ...200312814647
electron microscopic study of in vitro cultures of hammondia heydorni (berlin 1996) tachyzoites after passages through dogs, mice, rats, guinea pigs and jirds.this study describes the fine structure and reproduction of tachyzoites of hammondia heydorni (isolate berlin 1996) after in vitro cultivation of stages isolated from serial passages between dogs and various intermediate hosts such as mice, rats, guinea pigs, jirds, knock-out mice, goats and sheep. the tachyzoites are identical with respect to their ultrastructural features to the corresponding stages of the nc-1-strain of neospora caninum. this fact conforms with other already published data an ...200312838414
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
antibodies to neospora caninum in european brown hare (lepus europaeus).neospora caninum antibodies in european brown hares (lepus europaeus) were reported for the first time in sera collected from hares imported in italy from east europe. sera from 93 hares coming from hungary and 44 hares coming from slovakia were tested using a direct agglutination test (dat). seroprevalence was 8.0% at the 1:40 dilution and 1.5% at 1:320 dilution. seroprevalence in females and males and in different countries of origin did not differ significantly. our results indicate that euro ...200312860071
characterization of an alpha tubulin gene sequence from neospora caninum and hammondia heydorni, and their comparison to homologous genes from apicomplexa.the gene coding for a tubulin has been isolated by the polymerase chain reaction and sequenced from 2 isolates of neospora caninum (nc-liverpool and nc-sweb1). the data show that the gene, as in toxoplasma gondii, is single copy and contains 3 exons and 2 introns and is identical in sequence in the 2 isolates studied. comparison of the predicted protein sequence shows it to be identical to the a tubulin protein encoded by the t. gondii gene. the majority of the nucleotide substitutions that have ...200312866794
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
immunization of mice with plasmid dna coding for ncgra7 or ncshsp33 confers partial protection against vertical transmission of neospora caninum.the purpose of the present study was to use direct plasmid deoxyribonucleic acid (dna) injection to identify specific antigens that confer protection against congenital transfer of neospora caninum. inbred balb/c mice were vaccinated before pregnancy with a recombinant plasmid containing sequences encoding n. caninum antigen ncgra7 or ncshsp33. the mice were challenged with n. caninum tachyzoites at 10-12 days of gestation. whereas 100% of pups born from dams immunized with control plasmid conta ...200312880248
hammondia heydorni from the arabian mountain gazelle and red fox in saudi arabia.unsporulated oocysts were detected in the feces of an arabian red fox (vulpes vulpes arabica) between 6 and 8 days after it had been fed meat from arabian mountain gazelles (gazella gazella) known to contain sarcocysts. no oocysts were discovered in the feces of other experimental cubs, although sporocysts of sarcocystis spp. were passed subsequently by all cubs that were fed gazelle meat, including those fed with reem (g. subgutturosa marica). the oocysts sporulated in 3 days at room temperatur ...200312880254
protracted shedding of oocysts of neospora caninum by a naturally infected foxhound.feces from 15 dogs at 2 different foxhound kennels in the u.k. were examined microscopically for the presence of oocysts of neospora caninum. one sample containing approximately 400 candidate oocysts per gram was positive in a polymerase chain reaction (pcr) using n. caninum-specific primers. in a sample taken 4 mo later from the same hound. n. caninum oocysts were again detected visually and by pcr. this is the third reported case of a dog naturally excreting oocysts of n. caninum and suggests ...200312880273
the pathogenesis of neosporosis in pregnant cattle: inoculation at investigate the pathogenesis of bovine neosporosis, 14 pregnant cattle were each inoculated subcutaneously with either 10(7) or 5 x 10(8) neospora caninum (strain nc1) tachyzoites at 140 days' gestation. serial necropsies were then carried out over an 8-week period. in the placenta, neospora dna and histopathological changes were observed in samples taken 14 days post-inoculation (dpi), with focal necrosis of maternal caruncular septa and fetal placental villi, serum leakage, and a maternal a ...200312921725
seroprevalence of neospora caninum in aborting dairy cattle in the czech republic.a serological survey for antibodies against neospora caninum in aborting cattle was carried out in the czech republic. serum samples from 463 aborting dairy cows originated from 137 farms from different parts of the czech republic were tested for presence of n. caninum antibodies by use of an enzyme-linked immunosorbent assay (elisa) and an indirect fluorescent antibody test (ifat). antibodies (> or = 1:640) to n. caninum were found in 18 (3.9%) of 463 aborting cows. farm prevalence in aborting ...200312935739
development and evaluation of a seminested pcr for detection and differentiation of babesia gibsoni (asian genotype) and b. canis dna in canine blood samples.canine babesiosis has recently been recognized as an emerging infectious disease of dogs in north america. we sought to develop a seminested pcr to detect and differentiate babesia gibsoni (asian genotype), b. canis subsp. vogeli, b. canis subsp. canis, and b. canis subsp. rossi dna in canine blood samples. an outer primer pair was designed to amplify an approximately 340-bp fragment of the 18s rrna genes from b. gibsoni (asian genotype), b. canis subsp. vogeli, b. canis subsp. rossi, and b. can ...200312958243
laboratory passage and characterization of an isolate of toxoplasma gondii from an ocular patient in korea.toxoplasma gondii tachyzoites were isolated from the blood of an ocular patient, and have been successfully passaged in the laboratory, for over a year, by peritoneal inoculation in mice. the isolated parasite was designated the korean isolate-1 (ki-1) and its characteristics were compared with those of the rh strain, a wellknown virulent strain originating from a child who suffered from encephalitis. the morphology, pathogenicity, infectivity and cell culture characteristics of the ki-1 were si ...200312972728
elisa detection of igg antibody against a recombinant major surface antigen (nc-p43) fragment of neospora caninum in bovine 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
first demonstration of protective immunity against foetopathy in cattle with latent neospora caninum infection.the parasite neospora caninum is an important cause of abortion in cattle world-wide. chronically infected dams transmit the parasite transplacentally and infected foetuses may be aborted or born chronically infected but clinically normal. chronically infected cows repeatedly transmit the parasite to foetuses in several pregnancies and some may abort more than once suggesting that the immune response in these cattle is compromised during pregnancy. to investigate the nature of the immune respons ...200313129528
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
anti-protozoal efficacy of medicinal herb extracts against toxoplasma gondii and neospora caninum.the purpose of this study was to determine whether alcohol extracts of herbs (sophora flavescens aiton, sinomenium acutum (thunb.) rehder and e.h. wilson, pulsatilla koreana (yabe ex nakai) nakai ex t. mori, ulmus macrocarpa hance and torilis japonica (houtt.) dc.) from south korea, possess in vitro anti-protozoal activity against cultures of toxoplasma gondii and neospora caninum. these herbs have been used as human anti-parasitics in asian countries for many years. alcohol extracts of these he ...200314519322
dermatitis in a dog associated with an unidentified toxoplasma gondii-like parasite.protozoal dermatitis was diagnosed in a 6-year-old female great dane dog from rio de janeiro, brazil. the dog died because of a chronic illness with an ehrlichia-like organism. numerous apicomplexan parasites were identified histologically in the section of dermal lesions. the protozoan reacted with toxoplasma gondii polyclonal rabbit serum but not with neospora caninum or sarcocystis neurona antibodies. ultrastructurally, the protozoa was not t. gondii because it had schizont-like structures wi ...200314519327
cytokine gene expression in dams and foetuses after experimental neospora caninum infection of heifers at 110 days of gestation.neospora caninum is a major cause of abortion in cattle. an essential role for th1 cytokines, such as ifn-gamma and il-12 in protective immunity against n. caninum in murine models has been indicated. however, little is known about immunity to neospora in pregnant cattle where a considerable level of immunomodulation may exist. in this study, the immune response of heifers infected early in the second trimester of pregnancy by intravenous inoculation of n. caninum tachyzoites was compared with i ...200314521581
prevalence of antibodies to neospora caninum, sarcocystis neurona, and toxoplasma gondii in wild horses from central wyoming.sarcocystis neurona, neospora caninum, n. hughesi, and toxoplasma gondii are 4 related coccidians considered to be associated with encephalomyelitis in horses. the source of infection for n. hughesi is unknown, whereas opossums, dogs, and cats are the definitive hosts for s. neurona, n. caninum, and t. gondii, respectively. seroprevalence of these coccidians in 276 wild horses from central wyoming outside the known range of the opossum (didelphis virginiana) was determined. antibodies to t. gond ...200314533680
meningoencephalitis associated with an unidentified apicomplexan protozoan in a pacific harbor seal.a pacific harbor seal (phoca vitulina richardsii) was found on the central california coast with neurologic signs and labored breathing, which were unresponsive to treatment. necropsy revealed a nonsuppurative necrotizing meningoencephalitis, a multilocular thymic cyst, and nonsuppurative cystitis and renal pyelitis. microscopic examination revealed protozoans in the brain, thymic cyst, and bladder mucosa. ultrastructurally, the protozoal tachyzoites were different from those of neospora caninum ...200314533706
autofluorescence of toxoplasma gondii and related coccidian oocysts.this is the first report of blue autofluorescence as a useful characteristic in the microscopic detection of toxoplasma gondii, hammondia hammondi, hammondia heydorni, neospora caninum, besnoitia darlingi, and sarcocystis neurona oocysts or sporocysts. this autofluorescence is of sufficient intensity and duration to allow identification of these oocysts from complex microscopic sample backgrounds. as with the autofluorescence of related coccidia, the oocysts glow pale blue when illuminated with ...200314533708
seroprevalence of neospora caninum and toxoplasma gondii antibodies in the south american opossum (didelphis marsupialis) from the city of são paulo, brazil.antibodies to neospora caninum and toxoplasma gondii were assayed in sera of 396 opossums (didelphis marsupialis) from the city of são paulo, brazil. antibodies to n. caninum were assayed using the indirect immunofluorescent antibody test (ifat). antibodies (ifat, approximately 1:25) to n. caninum were found in 84 opossums (d. marsupialis) in titers of 1:25 in 46, 1:50 in 20, 1:100 in 17, and 1:400 in 1. antibodies to t. gondii were assayed with the modified agglutination test (mat) and the ifat ...200314533710
isolation of neospora caninum from a blind calf in paraná, southern brazil. 200314533770
neospora caninum and toxoplasma gondii: a novel adhesion/invasion assay reveals distinct differences in tachyzoite-host cell interactions.this paper describes an adhesion/invasion assay, based on combined pyrrolidine dithiocarbamate (pdtc) and antibody treatment of parasites followed by quantitative real-time pcr. this pdtc-pcr assay can be used to comparatively assess the participation of host cell- and parasite-associated components during host cell adhesion and entry by neospora caninum and toxoplasma gondii tachyzoites, respectively, and is potentially applicable to any other apicomplexan parasite. the assay allows to determin ...200314552862
a role for balance of interferon-gamma and interleukin-4 production in protective immunity against neospora caninum infection.a suitable balance in the production of th1/th2-type cytokines has a crucial role in the control of microbial infections. we investigated cytokine production patterns and effects during neospora caninum infection, based on two mouse models and an in vitro system. in the acute infection of n. caninum, balb/c-background ifn-gamma-deficient mice that were sensitive to the n. caninum infection showed high levels of il-10 production, whereas significant levels of interferon-gamma (ifn-gamma) and inte ...200314559161
toxoplasma gondii, neospora caninum, sarcocystis neurona, and sarcocystis canis-like infections in marine mammals.toxoplasma gondii, neospora caninum, sarcocystis neurona, and s. canis are related protozoans that can cause mortality in many species of domestic and wild animals. recently, t. gondii and s. neurona were recognized to cause encephalitis in marine mammals. as yet, there is no report of natural exposure of n. caninum in marine mammals. in the present study, antibodies to t. gondii and n. caninum were assayed in sera of several species of marine mammals. for t. gondii, sera were diluted 1:25, 1:50 ...200314580799
seroprevalence of neospora caninum and toxoplasma gondii in captive and free-ranging nondomestic felids in the united serum samples of 101 samples from nondomestic, captive and free-ranging felids from the united states were indirect fluorescent antibody positive for antibodies to neospora caninum, whereas 44 samples were positive for antibodies to t. gondii. although none of the captive animals displayed clinical signs of disease, nondomestic felids in the united states have been exposed to, and are likely infected with, n. caninum and t. gondii. this may have serious implications for zoological gardens ...200314582785
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
detection of hammondia heydorni-like organisms and their differentiation from neospora caninum using random-amplified polymorphic dna-polymerase chain reaction.neospora caninum and hammondia heydorni are morphologically and phylogenetically related coccidians that are found in dogs. new diagnostic genetic loci, based on random-amplified polymorphic dna-polymerase chain reaction (rapd-pcr), were developed to aid in the detection of h. heydorni-like parasites and to discriminate them from n. caninum and other related coccidians of dogs. on the basis of the data obtained from 5 random decamers, h. heydorni (manhattan-1) and n. caninum (nc1) were character ...200314627168
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
neospora caninum in sheep: a herd case report.neospora caninum was detected by means of pcr in the brain of 4 out of 20 aborted fetuses in a flock of 117 sheep exhibiting a persistent abortion problem, and n. caninum tissue cysts were furthermore found in encephalitic lesions in one of the pcr-positive fetuses. toxoplasma gondii was detected as aborting agent in another 3 out of 20 fetuses. antibodies to n. caninum (by indirect fluorescence antibody test (ifat)) were found in 10.3% of 117 ewes and antibodies for t. gondii were found in 97.4 ...200314630429
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
neospora caninum infection and congenital transmission: serological and parasitological study of cows up to the fourth 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 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
detection of neospora caninum in semen of cattle, transplacental infection is the main route of neospora caninum transmission, but postnatal transmission by the oral uptake of sporozoite-containing oocysts shed by dogs may also be possible. other routes of horizontal transmission, such as the venereal route, have not been investigated. in this study, we evaluated the presence of n. caninum dna by a nested-pcr in fresh non-extended semen and frozen extended semen straws of five holstein-friesian bulls with naturally-acquired neosporos ...200314637032
a long-term study of neospora caninum infection in a swedish dairy herd.a longitudinal study was performed in a swedish dairy herd where neospora caninum had been isolated from a stillborn calf. starting in autumn 1994, blood samples from all female animals in the herd were collected once yearly until 1999. the sera were analysed for presence of igg1 antibodies to n. caninum by the iscom elisa, and by an avidity elisa to establish the timing of infection. in addition, data on reproductive performance were compiled. during the study the percentage of seropositive fem ...200314650545
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
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
antibodies to neospora caninum in wild animals from kenya, east africa.the prevalence of antibodies to neospora caninum was examined in six wild artiodactyla species, and in five wild carnivora species from kenya. blood sera (104 wild ungulates from marula estates (mes), and 31 wild carnivores from masai-mara reserve and from other wildlife areas in northern and southern kenya), were screened using a neospora agglutination test (nat), with a twofold dilution (1:40-1:320 titres). presence of nat antibodies to n. caninun is reported here for the first time in zebra ( ...200314651874
use of a multiplex polymerase chain reaction assay in the antemortem diagnosis of toxoplasmosis and neosporosis in the central nervous system of cats and develop a multiplex polymerase chain reaction (pcr) assay for the detection of toxoplasma gondii and neospora caninum dna in canine and feline biological samples. sample population; biological samples from 7 cats with systemic (n = 4) or cns (3) toxoplasmosis, 6 dogs with neospora- or toxoplasma-associated encephalitis, and 11 animals with nonprotozoal disease.200314672429
establishment of a two-dimensional electrophoresis map for neospora caninum tachyzoites by proteomics.expressed proteins and antigens from neospora caninum tachyzoites were studied by two-dimensional gel electrophoresis and immunoblot analysis combined with matrix-assisted laser desorption/ionization-time of flight mass spectrometry. thirty-one spots corresponding to 20 different proteins were identified from n. caninum tachyzoites by peptide mass fingerprinting. six proteins were identified from a n. caninum database (ntpase, 14-3-3 protein homologue, ncmic1, ncdg1, ncgra1 and ncgra2), and 11 p ...200314673785
apiest-db: analyzing clustered est data of the apicomplexan parasites.apiest-db ( provides integrated access to publicly available est data from protozoan parasites in the phylum apicomplexa. the database currently incorporates a total of nearly 100,000 ests from several parasite species of clinical and/or veterinary interest, including eimeria tenella, neospora caninum, plasmodium falciparum, sarcocystis neurona and toxoplasma gondii. to facilitate analysis of these data, est sequences were clustered and assembled to for ...200414681425
in vitro induction of neospora caninum bradyzoites in vero cells reveals differential antigen expression, localization, and host-cell recognition of tachyzoites and bradyzoites.we report on an optimized method for the in vitro culture of tissue cyst-forming neospora caninum bradyzoites in vero cells and the separation of viable parasites from host cells. treatment of tachyzoite-infected vero cell cultures with 17 microm sodium nitroprusside for 8 days severely scaled down parasite proliferation, led to reduced expression of tachyzoite surface antigens, and induced the expression of the bradyzoite marker ncbag1 and the cyst wall antigen recognized by the monoclonal anti ...200414688139
seroprevalence of antibodies to neospora caninum in dogs and raccoon dogs in korea.neospora caninum is an important cause of abortion in cattle, and dogs are its only known definitive host. its seroprevalence among domestic urban and rural dogs and feral raccoon dogs (nyctereutes procyonoides koreensis) in korea was studied by indirect fluorescent antibody test (ifat) and by the neospora agglutination test (nat), respectively. antibodies to n. caninum were found in 8.3% of urban dogs and in 21.6% of dogs at dairy farms. antibody titers ranged from 1:50 to 1:400. antibodies to ...200314699266
first cases of animal diseases published since 2000. 5. this fifth article of a series of papers listing first case reports of animal diseases published since 2000, the following five cases of sheep diseases are discussed: ependymoma. mastitis caused by burkholderia cepacia infection. meningoencephalitis associated with globicatella sanguinis infection. neospora caninum infection in an adult sheep and her twin fetuses. plasma cell tumor. after a short introduction, the bibliographical data, the abstract of the author(s), and some additional inform ...200314714740
serodiagnosis of neospora caninum infection in cattle by enzyme-linked immunosorbent assay with recombinant truncated ncsag1.neospora caninum is a veterinary medically important pathogen capable of causing abortion in cattle and neuromuscular paralysis in dogs. the surface antigen 1 of n. caninum (ncsag1) is an important candidate for the development of a diagnostic reagent for neosporosis. in order to establish an effective diagnostic method, the gene encoding truncated ncsag1 (ncsag1t) lacking a signal peptide and c-terminal hydrophobic regions was cloned and expressed in escherichia coli as a fusion protein with gl ...200314729165
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
effects of toltrazuril and ponazuril on hammondia heydorni (syn. neospora caninum) infections in mice.mice infected with tachyzoites of neospora caninum (syn.: hammondia heydorni) must be pretreated with cortisone in order to show disease symptoms. this indicates the status of an opportunistic agent of disease. toltrazuril was an effective curative agent.200414963771
effects of toltrazuril and ponazuril on the fine structure and multiplication of tachyzoites of the nc-1 strain of neospora caninum (a synonym of hammondia heydorni) in cell cultures.rhesus monkey kidney cell cultures were used to propagate tachyzoites of the nc-1 strain of neospora caninum (syn. hammondia heydorni). the infected cell cultures were incubated for 4-12 h in media containing 0, 1, 10 or 100 microg/ml of either toltrazuril or ponazuril. the effects were studied by light and electron microscopy. drug dosages of at least 30 microg/ml were needed to eliminate the parasites. ponazuril was found (with respect to the reduction of the number of parasites) to be less ef ...200414963772
inclusion of cpg adjuvant with plasmid dna coding for ncgra7 improves protection against congenital neosporosis.the present study showed that incorporation of cpg adjuvant into plasmid dna coding for ncgra7 antigen resulted in a twofold increase in the level of protection against congenital transfer of neospora caninum. the level of protection was considerably higher than that observed in pups born from dams immunized with nonrecombinant plasmid.200414977994
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
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
adaptation of a commercial elisa for the detection of antibodies against neospora caninum in bovine milk.the aim of the present study was to determine whether a commercially available elisa could be used to examine bovine milk for antibodies against neospora caninum. in an initial titration experiment, a milk dilution of 1:2 was found optimal to obtain milk results that were linearly correlated to those obtained with corresponding sera. this dilution was then used to examine 791 milk samples from n. caninum infected herds in the commercial elisa. milk results of individual animals were compared wit ...200415019143
seroepidemiology of neosporosis in dairy cattle in uruguay.a seroepidemiological survey of neospora caninum was done in a dairy farm in uruguay employing indirect fluorescent antibody test (ifat). sera from 217 cattle (155 cows, 31 heifers and 31 calves) were tested for n. caninum antibodies in july 2000 and it was found that abortions were significantly associated with the seropositivity of the cows by chi(2)-test (p = 0.025). the cows with an ifat titre of 1:3200 were at a significantly higher risk of abortion than seronegative cows (p = 0.0013). neos ...200415019151
the vertical transmission following the reactivation of a neospora caninum chronic infection does not seem to be due to an alteration of the systemic immune response in pregnant cba/ca mice.the factors responsible for the reactivation of a neospora caninum latent infection are unknown, but it is postulated that the maternal immune response could be altered during pregnancy. the immune response was investigated in n. caninum chronically infected mice during successive pregnancies as well as in non-pregnant infected mice and mice infected when pregnant. vertical transmission was demonstrated in chronically infected mice after the first pregnancy but the rate of foetal infection fell ...200415030002
effect of bovine viral diarrhea virus infection on fertility of dairy heifers.a prospective field study in heifers from birth to first breeding was undertaken on two commercial dairies to assess the effect of bovine viral diarrhea virus (bvdv) congenital and post-natal infection (pni) on fertility. a high bvdv type 2 antibody titer (1:4096) at 10 months of age was associated with 32 more days to conceive, compared with a low titer (1:128). conversely, infection with bvdv by 5-6 months of age and high bvdv type 2 titers 1 month before conception or breeding was associated ...200415036997
coyotes (canis latrans) are definitive hosts of neospora caninum.four captive-raised coyote pups consumed tissues from neospora caninum-infected calves. faeces were examined from 4 days before to 28 days after infection. one pup shed n. caninum-like oocysts, which tested positive for n. caninum and negative for hammondia heydorni using pcr tests. coyotes are the second discovered definitive host of n. caninum, after dogs. in north america, the expanding coyote ranges and population increase the probability of contact with domestic livestock. to reduce the ris ...200415037103
variation of the internal transcribed spacer 1 sequence within individual strains and among different strains of neospora caninum.small differences have been reported in the internal transcribed spacer 1 (its1) region among strains of neospora caninum. we compared its1 sequences among 6 n. caninum strains analyzed in our laboratory, including 2 strains that have not been examined previously (nc-illinois and nc-bahia). five sequences showed 100% similarity and also were identical to 7 of 11 sequences that were previously reported by others. in contrast, initial attempts to sequence the its1 of nc-bahia generated 12 nucleoti ...200415040677
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
prevalence of antibodies to neospora caninum within central queensland beef cattle. 200315080432
an outbreak of abortion in a dairy herd associated with neospora caninum and bovine pestivirus infection. 200415088970
survival, immune responses and tissue cyst production in outbred (swiss white) and inbred (cba/ca) strains of mice experimentally infected with neospora caninum tachyzoites.the present work compared inbred (cba/ca) and outbred (swiss white) strains of mice for their capacity to cope with a neospora caninum infection and to consistently produce tissue cysts. in each experiment swiss white and cba/ca mice were given three different doses of nc-1 tachyzoites. lymphoproliferative and humoral responses as well as cytokine production were evaluated eight weeks after infection (pi) whereas tissue cyst production and histopathology were assessed 4, 6 and 10 weeks pi in imm ...200415099498
neospora caninum expresses an unusual single-domain kazal protease inhibitor that is discharged into the parasitophorous vacuole.serine protease inhibitors have been implicated in viral and parasite pathogenesis through their ability to inhibit apoptosis, provide protection against digestive enzymes in the gut and dictate host range specificity. two kazal family serine protease inhibitors from the obligate intracellular parasite toxoplasma gondii (tgpi-1 and tgpi-2) have been characterised previously. here, we describe the identification and initial characterisation of a novel kazal inhibitor, ncpi-s, from a closely relat ...200415111091
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
an abortion storm in cattle associated with neosporosis in 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 seroprevalence in dairy cattle in central thailand.the seroprevalence, in dairy cattle, of antibodies to neospora caninum, the relationship between seropositivity and age (heifer versus cow), the relationship of herd infection with herd size and the relationship of herd infection with the presence of dogs on the farm were studied. the study involved 549 cows and 82 dogs in 59 dairy herds in nakhon pathom, thailand. a competitive enzyme-linked immunosorbent assay (celisa) with nc-specific monoclonal antibody was used to detect the nc antibodies i ...200415135865
vertical transmission of neospora caninum in balb/c mice in both acute and chronic examine the frequency of congenital infection by neospora caninum, balb/c mice were inoculated intraperitoneally with tachyzoites of n. caninum either during pregnancy (group 1) or 4 weeks or more before pregnancy (group 2). further, the mice inoculated during pregnancy were bred at 4 weeks or more after delivery to form group 3. congenital transmission was observed in 76% of the neonates of the mice in group 1 and in 50% of the neonates of the mice in group 2. interestingly, congenital trans ...200415135873
identification and characterization of serine proteinase inhibitors from neospora caninum.two cdna clones obtained from the neospora caninum expressed sequence tag project were selected by their homology with the toxoplasma gondii serine proteinase inhibitor (serpin) gene, tgpi-1 and tgpi-2. one of them, named ncpi-h, showed several premature stop codons. the other cdna, named ncpi-s, encoded a 79 amino acid protein containing a putative signal peptide and only one non-classical kazal domain. two other n. caninum est sequences (ncest1 and ncest2) and one from eimeria tenella (etpi-s) ...200415138071
economic considerations for diagnostic and control options for neospora caninum-induced abortions in endemically infected herds of beef 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
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