Seroprevalence of Neospora caninum and Toxoplasma gondii in camels (Camelus dromedarius) in Mashhad, Iran

One hundred twenty camels were blood-sampled and used to evaluate serological screening for Neospora caninum and Toxoplasma gondii infection by indirect fluorescent antibody test (IFAT) in Mashhad, Iran, during years 2004–2005. Of the 120 camels, antibodies to N. caninum were found in three in titers of 1:20 and in four in titers of 1:40 using whole N. caninum tachyzoites as IFAT slide (VMRD Inc., Pullman, WA 99163, USA). Antibodies to T. gondii were found in three camels in titers 1:20 and in two camels in titers 1:40 using whole T. gondii tachyzoites as IFAT slide (BIOGENE, Iran).     

Seroprevalence of Neospora caninum infection in dogs in Chaharmahal-va-Bakhtiari Province, Iran

The aim of this study was to determine seroprevalence of Neospora caninum infection in dogs in Chaharmahal-va-Bakhtiari province in Iran. One hundred serum samples were collected from dogs of different sex, age, and breed. Collected serum samples were examined using an indirect fluorescent antibody test. Thirty-two of the examined samples showed detectable IgG antibodies in titers of 1:50. Dogs older than one year old and stray dogs had a higher seroprevalence than other dogs. No sex or breed predispositions to N. caninum infection were detected during this serological assay (P ≤ 0.05).     

Diagnosis of Sarcocystis cruzi, Neospora caninum, and Toxoplasma gondii infections in cattle

The aim of the study was to diagnose Sarcocystis sp. infections in cattle and to detect coinfections by Toxoplasma gondii and/or Neospora caninum. Blood, diaphragm, esophagus, and myocardium from 90 beef cattle from Argentina were collected. Histopathological, immunohistochemical, polymerase chain reaction assays, and direct microscopical examination were carried out. Sarcocysts from myocardium were measured and counted. Indirect fluorescent antibody test (IFAT) for the three protozoans was performed. Sarcocystis cruzi sarcocysts were found in 100% of myocardium samples. Sarcocysts per gram ranged from 8 to 380 with higher values found in adult cattle (p < 0.001). T. gondii and N. caninum were not detected by immunohistochemistry. T. gondii DNA was found in myocardium of 2/20 seropositive animals, while N. caninum DNA was not found. Antibodies against S. cruzi were detected in all samples, those against N. caninum in 73% and against T. gondii in 91% of the samples (IFAT titer ≥25). It is concluded that serology by IFAT is a suitable method to diagnose these protozoan infections due to its specific IgG detection; therefore, IFAT may be a useful tool to evaluate the impact of each protozoan infection in coinfected animals. Financial support for this study was provided by SeCyT through BID 1728 PICT No. 10858/8.     

Kennel dogs as sentinels of Leishmania infantum, Toxoplasma gondii, and Neospora caninum in Majorca Island, Spain

Kennel dogs can serve as sentinels and/or reservoirs of diseases of veterinary and zoonotic interest because they have often roamed free and lived outdoors, thus being exposed to pathogens. We tested dogs from the kennel of Inca (Majorca/Mallorca, Balearic Islands, Spain) for evidence of infection with three protozoan parasites: Leishmania infantum, Toxoplasma gondii, and Neospora caninum. Exposure to L. infantum was found in 56.3% of 48 dogs (37.5% by Western blot, 43.8% by PCR). Only 30% of infected dogs had leishmaniosis-like lesions. Seroprevalence to T. gondii was 58.7% of 46 dogs using the modified agglutination test (MAT, titer 1:25). None of the 44 dogs tested had N. caninum antibodies using a commercial competitive ELISA, probably because the surveyed dogs did not roam in the proximity of cattle farms. Results confirm the endemicity of L. infantum and also the widespread presence of T. gondii in the Mediterranean island of Majorca.     

Seroprevalence of Neospora caninum in cats from the Czech Republic

Sera of 414 cats coming from different parts of the Czech Republic were tested for N. caninum antibodies. Sera samples were collected during years 2002–2011. N. caninum antibodies were detected by a commercial competitive-inhibition enzyme-linked immunosorbent assay (cELISA) with cut off ≥30% inhibition. Samples positive in cELISA were confirmed by an indirect fluorescence antibody test (IFAT); titre ≥50 was considered positive. In total, 137 (33%) cats reacted positively in cELISA; N. caninum antibodies in IFAT were detected in 16 (3.86%) cats with titres 50 and 100. In 6 cats, positive for N. caninum antibodies, T. gondii antibodies were also detected by IFAT. It is the first report of N. caninum antibodies in domestic cats from the Czech Republic and third report in Europe.     

Seroprevalence of Toxoplasma gondii infection in shepherd dogs from Sarab District,Northwest Iran

The aim of this study was to compile initial epidemiological data on the prevalence of Toxoplasma gondii antibodies in Sarab area. We evaluated the titers of anti-T. gondii antibodies by latex agglutination test (LAT; titer?>?1:64) serological test in 39 (10.1 %) serum samples from shepherd dogs exhibiting clinical signs of infectious diseases. The largest age group was 2–4 years, with 170 (44.3 %) dogs out of which only 21 dogs (12.3 %) were seropositive and the lowest age group was 4–6 years, with 87(22.6 %) out of which only 3 dogs (3.4 %) were seropositive. The highest rate of infection was seen in Ardaha village, with 11 (27.5 %) dogs. The lowest rate of infection was detected in Khaki and Asbfroshan villages, with only one dog. According to dog breed, the seropositivity rate of T. gondii was 14.3 % in pure breed dogs and 11.2 % in mongrel dogs. No sex or breed predispositions to T. gondii infection were detected during this serological assays (P?≤?0.05). The antibody titres of T. gondii ranged from 1:64 to 1:2,084. 39 Seropositive dogs with titers of 1:64 in 10, 1:128 in 13, 1:256 in 5, 1:512 in 6, 1:1,024 in 3, and 1:2,084 in 2 dog. In the present study, there was no correlation between antibody titers and, age or location. Our results show that presence and exposure of shepherd dogs to T. gondii in Sarab city confirm that dogs are exposed to T. gondii and play an important role in the epidemiology of T. gondii of this region.     

Comparison of the internal transcribed spacer, ITS 1, from Toxoplasma gondii isolates and Neospora caninum

The internal transcribed spacer (ITS1) region and the 5′ part of the 5.8S ribosomal RNA gene of the ribosomal DNA repeat from 20 Toxoplasma gondii isolates was sequenced and found to be identical in all isolates, independent of host origin or virulence to mice. The ITS1 region from the closely related coccidian parasite Neospora caninum differed in 22% of its nucleotides. Hence, the ITS1 region provides a good marker for the distinction of T. gondii and N. caninum but is not useful for epidemiology studies of T. gondii.     

Diagnosis of Neospora caninum and Toxoplasma gondii infection by PCR and DNA hybridization immunoassay.

A recently described PCR test for the identification of Neospora caninum and Toxoplasma gondii has been further developed and optimized in view of its practicability for routine diagnostic application. The N. caninum-specific PCR was adapted to the diagnostic operating standard of the T. gondii-specific PCR in that the uracil DNA glycosidase system was introduced, which eliminates potential carry-over contaminations of amplified target DNA from previous reactions. Furthermore, both PCR tests were optimized by including a DNA hybridization immunoassay based on the use of the commercially available Gen-eti-k DEIA kit. This assay allowed highly sensitive and specific detection of respective DNA amplification products and thus substantially facilitated the reading and interpretation of the test results.     

Seroprevalence of Neospora caninum in racehorses in Ankara, Turkey

To assess seroprevalence of Neospora spp. in asymptomatic horses in Ankara, Turkey, 19 mares and 56 stallions older than 2 years of age were examined using ELISA; 9.3% of the horses were seropositive. Seroprevalence of N. caninum in mares was twice of that in stallions (15.8 vs 7.1%) and all appeared to be asymptomatic.     

Seroepidemiology of Toxoplasma gondii, Neospora caninum, and Leishmania spp. infections and risk factors for cats from Brazil

The seroprevalence of infection by Toxoplasma gondii, Neospora caninum, and Leishmania spp. was detected through an indirect immunofluorescence in 70 cats from the Andradina Municipality, S?o Paulo State, Brazil. Anti-T. gondii antibodies (titer >64) were detected in 15.7% (11/70) of animals, whereas positivity for N. caninum (titer 16) was not observed in any animal. Of the cats from urban and rural areas, 10.4% (5/48) and 27.2% (6/22) were positive for T. gondii, respectively. Breed, age, food, and contact with animals of other species were significant for considering the positivity for T. gondii (P ≤ 0.0001). Cats having access to streets (17.1%, 11/64), cats cohabiting with rats (19.6%, 10/51), and cats feeding on homemade food and raw milk (27.2%, 6/22) were positive for T. gondii. In addition, 4.2% (3/70) of the cats were positive for Leishmania spp. by ELISA technique and negative by IFAT without coinfection with T. gondii and Leishmania spp. There was no serological positivity against feline immunodeficiency virus or feline leukemia virus. In conclusion, T. gondii infection in part of the feline population from Andradina is not linked to immunosuppressions or coinfections but probably to postnatal infection in association with the type of diet and presence of rats.     

Investigation of Neospora caninum, Hammondia sp., and Toxoplasma gondii in tissues from slaughtered beef cattle in Bahia, Brazil

Neospora caninum, Hammondia sp., and Toxoplasma gondii are parasites with morphological and genetic similarities. N. caninum and T. gondii are important abortive agents of cattle and sheep, respectively, and may infect numerous animal species. Hammondia sp. is not known to induce disease in animals, but may cause confusion in the identification of closely related coccidia. The aim of this study was to investigate infection rates caused by N. caninum, Hammondia sp., and T. gondii in beef cattle using a nested PCR for Toxoplasmatinae rDNA, followed by sequencing of the PCR products. Antibodies to N. caninum and T. gondii were also investigated in the tested animals. Brains and hearts were obtained from 100 beef cattle in a slaughterhouse in Bahia. Seven samples from brain tested positive for Toxoplasmatinae DNA. No positive reactions were found in heart tissues. After sequencing of the PCR products from all positive tissues, five sequences matched with N. caninum and two matched with T. gondii. Antibodies to N. caninum and T. gondii were found in 20% and 26% of the animals, respectively. The confirmation of N. caninum and the absence of Hammondia heydorni in the tested animals is suggestive that cattle are not efficient intermediate hosts of H. heydorni; however further studies need to be performed using a greater variety of tissues and a higher sample size. The detection of T. gondii DNA in bovine tissues reinforces the potential risk of transmission of this parasite to humans and other animals through the consumption of bovine meat.     

Toxoplasma gondii, Neospora caninum and tick-transmitted bacterium Anaplasma phagocytophilum infections in one selected goat farm in Slovakia

Parasitic diseases of livestock together with poor welfare conditions can negatively affect the health status and production of small ruminants. Protozoan parasites and tick-borne infectious agents are common threat of livestock including small ruminants mostly during the pasture season. Therefore the priority of the study was to analyse the circulation and presence of two protozoan parasites Toxoplasma gondii and Neospora caninum as well as tick-transmitted bacterium Anaplasma phagocytophilum in one selected goat farm in Eastern Slovakia. Throughout a three-year study period we have repeatedly screened the sera and blood of goats and dogs from monitored farm. In total, 343 blood serum samples from 116 goats were examined by ELISA. The mean seropositivity for T. gondii was 56.9% (66/116, CI (95%) = 48–66.0) and 15.5% (18/116, CI (95%) = 9.3–22.7) for N. caninum. The permanent occurrence of anti-Toxoplasma and anti-Neospora antibodies was detected in repeatedly examined goats during the whole monitored period. The presence of both parasites in the flock was analysed by PCR. DNA of T. gondii was confirmed in 12 out of 25 Toxoplasma-seropositive goats and N. caninum in 14 samples out of 18 Neospora-seropositive animals; four goats were co-infected with both pathogens. The risk of endogenous transmission of both parasites was pursued by examination of 41 kid’s sera, where seropositivity for toxoplasmosis was 31.7% and for neosporosis 14.6%. In dogs 61.1% seropositivity for T. gondii and 38.9% for N. caninum was found, however, their faeces were negative for coccidian oocysts. Eight out of 108 tested animals were infected with A. phagocytophilum, the causative agent of tick-borne fever. Seven of them were simultaneously infected with T. gondii and A. phagocytophilum, out of which four goats were concurrently infected with all three pathogens.     

Identification of the cross-reactive and species-specific antigens between Neospora caninum and Toxoplasma gondii tachyzoites by a proteomics approach

The characterization of the cross-reactive and species-specific antigens of Neospora caninum and Toxoplasma gondii is important in the exploration to determine the common mechanisms of parasite-host interaction and to improve the serological diagnosis; it is also useful for the selection of the cross-reactive antigens that could be used in the development of vaccines or drugs for controlling the diseases caused by these two parasites. In this study, cross-reactive and species-specific antigens between N. caninum and T. gondii tachyzoites were comprehensively investigated using a proteomics approach with the application of two-dimensional gel electrophoresis, immunoblot analysis, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS), and MALDI-TOF/TOF-MS analysis. Immunoblotting and mass spectrometry analysis revealed that at least 42 individual protein spots of N. caninum were reacted with the anti-N. caninum serum, among which at least 18 protein spots were cross-reacted with the anti-T. gondii serum. Moreover, at least 31 protein spots of T. gondii were reacted with the anti-T. gondii serum, among which at least 19 protein spots were cross-reacted with the anti-N. caninum serum. Furthermore, some new specific proteins were also identified in the N. caninum protein profile by searching Toxoplasma sequences or sequences from other organisms. This study substantiates the usefulness of proteomics in the immunoscreening of the cross-reactive or species-specific antigens of both parasites. In addition, the present study showed that there was significant homology in the antigenic proteome profiles between the two parasites. These observations have implications for the design of multicomponent common vaccines against both parasite infections.     

Seroprevalence of Toxoplasma gondii in Iberian pig sows

Parasitology Research - The objective of the present study was to investigate the seroprevalence of Toxoplasma gondii infection in Iberian sows reared in extensive and intensive management...     

Reevaluation of the Toxoplasma gondii and Neospora caninum genomes reveals misassembly,karyotype differences,and chromosomal rearrangements

Neospora caninum primarily infects cattle, causing abortions, with an estimated impact of a billion dollars on the worldwide economy annually. However, the study of its biology has been unheeded by the established paradigm that it is virtually identical to its close relative, the widely studied human pathogen Toxoplasma gondii. By revisiting the genome sequence, assembly, and annotation using third-generation sequencing technologies, here we show that the N. caninum genome was originally incorrectly assembled under the presumption of synteny with T. gondii. We show that major chromosomal rearrangements have occurred between these species. Importantly, we show that chromosomes originally named Chr VIIb and VIII are indeed fused, reducing the karyotype of both N. caninum and T. gondii to 13 chromosomes. We reannotate the N. caninum genome, revealing more than 500 new genes. We sequence and annotate the nonphotosynthetic plastid and mitochondrial genomes and show that although apicoplast genomes are virtually identical, high levels of gene fragmentation and reshuffling exist between species and strains. Our results correct assembly artifacts that are currently widely distributed in the genome database of N. caninum and T. gondii and, more importantly, highlight the mitochondria as a previously oversighted source of variability and pave the way for a change in the paradigm of synteny, encouraging rethinking the genome as basis of the comparative unique biology of these pathogens.

The Apicomplexa comprise a large phylum of parasitic alveolates of medical and veterinary importance, causing deadly diseases such as malaria, cryptosporidiosis, neosporosis, and toxoplasmosis, among others. With the exception of a few commonalities such as their obligatory intracellular lifestyle and the presence of specialized secretory organelles and of secondary endosymbionts, the apicomplexans differ greatly in morphology, host range specificity, pathogenicity, reproductive strategy, and transmission. Understanding the molecular basis of these differences has been the focus of much research. Comparative genomic analyses revealed that, albeit all small, apicomplexans genomes vary greatly in size, ranging from 9 to 130 Mb (Debarry and Kissinger 2011; Blazejewski et al. 2015). Having diverged from a common ancestor 350–824 myr ago (Escalante and Ayala 1995), shy of 900 genes are conserved among them, whereby major genomic rearrangements can be observed (Debarry and Kissinger 2011).High synteny, defined as conserved content and order of a given genomic locus, is rarely observed (Debarry and Kissinger 2011). A seemingly stark exception to this is the genomes of Toxoplasma gondii and Neospora caninum. Morphologically, these parasites are virtually indistinguishable, so much so, that N. caninum was only recognized as a separate species in 1988 (Dubey 2003; Dubey et al. 2002). Moreover, both species show similar tropism within their hosts, where they can infect virtually any nucleated cell. They both show a fast-replicating form (tachyzoite), causing acute disease, that transitions into a slow-dividing form (bradyzoite), which persists in immune-privileged sites, such as the brain, establishing chronic infection. In line with this, initial comparative analysis concluded that these species have largely conserved genomic content and are largely syntenic (Reid et al. 2012). Despite their commonalities, however, the biology of these pathogens also differs significantly. T. gondii infects a wide range of intermediate hosts, including humans, causing deadly disease in immunocompromised individuals or by congenital transmission. In contrast, N. caninum infects primarily cattle, causing abortions with an estimated impact of a billion dollars on the worldwide economy annually (Reichel et al. 2013). Feline species act as definitive hosts of T. gondii, whereas sexual replication of N. caninum occurs only in canids (McAllister et al. 1998; Gondim et al. 2004; King et al. 2010). These biological differences have been largely ascribed to absence, point mutations, and pseudogenization of T. gondii virulence factors in N. caninum and the comparative amplification of surface protein-coding gene families in N. caninum (Khan et al. 2009; Reid et al. 2012).Advancements in genome sequencing technologies have accompanied the fast-paced genomics era. Particularly, third-generation sequencing technologies, such as Pacific Biosciences (PacBio) and Oxford Nanopore Technologies sequencing, outperform prior technologies by providing very long reads that can span regions containing repetitive sequences. This has led to improvements in the assembly of previously unattainable genomes, such as those presenting high proportions of repetitive sequences, allowing whole new genomes to be assembled with high accuracy. Here, we set out to sequence and de novo assemble two N. caninum strain genomes and the T. gondii genome, using PacBio and Oxford Nanopore.     

Serological study of Neospora caninum infection in dogs and cattle from west of Iran

The aim of this study was to determine the seroprevalence of Neospora caninum infection in dogs and cattle from Hamedan province (West of Iran). Blood samples were collected from 1,046 cattle and 270 dogs in this area. Cattle and dog samples were tested and analyzed using ELISA and IFAT, respectively. IgG-antibodies to N. caninum were found in 27 and 17.4 % of dogs and cattle samples, respectively. In cattle study, The association between infection and type of cattle was statistically significant (P?=?0.004). Also, significant statistical differences were observed regarding to stray canids presence in farm (P?P?P?=?0.195) and breed (P?=?0.077). In dog study, there was statistical differences among age groups (P?P?P?=?0.112). This study is the first report of N. caninum infection in dogs and cattle from west of Iran. There is both horizontal and vertical transmission of N. caninum in this area, and the presence of stray dogs may be a risk factor for N. caninum infection in cattle. N. caninum is an important factor in the economic losses of the cattle breeding in Hamedan province. Therefore, further investigations and designing control strategies for improving management in cattle farms is highly recommended.     

Seroprevalence of Neospora caninum infection in dairy cows in Northern provinces,Thailand

Neospora caninum, an obligate intracellular protozoan parasite, is the causative agent of neosporosis, recognized as a major cause of bovine abortion around the world. Thailand is a developing agricultural country located in Southeast Asia. Livestock developments particularly in dairy cows of this country have been hampered by low productivity including milk and slow growth rate due to the impact of many pathogens including N. caninum. Currently, there is no effective method for control of neosporosis since there is less information regarding current status of infections. The objective of this study was to investigate the seroprevalence of neosporosis in dairy cows of the northern part of Thailand. During 2006–2007, the sera of 642 cows from 42 small farm holders with the top three highest consensus of dairy farms in the northern provinces, such as Chiang Rai, Chiang Mai and Lumpang were collected and performed tests. Antibodies to N. caninum were assayed by enzyme-linked immunosorbent assay (ELISA) with recombinant N. caninum surface antigen 1 (NcSAG1) and indirect fluorescent antibody test (IFAT). The overall prevalence of N. caninum infection in this study was 46.9% (301/642) by ELISA and 34.3% (220/642) by IFAT.     

Prevalence of antibodies against Neospora caninum in dogs from urban areas in Central Poland

Neospora caninum is a protozoan parasite which causes abortion in cattle as well as reproduction problems and neurological disorders in dogs. To assess the prevalence of the parasite in urban dogs in the Mazovian Voivodeship, Central Poland, serum samples from 257 dogs were analyzed for the presence of specific IgG antibodies. The examined dogs visited three private veterinary clinics located in Warsaw due to control tests, vaccinations, or other reasons not directly connected with neosporosis. Using ELISA and Western blot, antibodies against the parasite were detected in 56 out of 257 dogs, giving a prevalence of 21.7%. A greater prevalence was observed in female dogs than in males, 28% and 17.3%, respectively, and the differences were statistically significant (p < 0.05). There were no significant differences in seroprevalence of Neospora infection within the age groups (p > 0.05). This study indicates the presence of N. caninum in the Mazovian Voivodeship, in dogs which live in urban areas and exposure of these dogs to the parasite. The fact that seropositive dogs had no contact with cattle confirms the important role of dogs in the parasite’s epidemiology.