Occurrence of antibodies and epidemiological significance of Toxoplasma Gondii and Neospora caninum infections in canine populations of Laguna, State of Santa Catarina.

Toxoplasma gondii and Neospora caninum are two species of protozoa that belong to the Apicomplexa phylum and are distributed worldwide. T. gondii is one of the most extensively studied parasites due to its significant health implications. In this study, an investigation on the occurrence of T. gondii and N. caninum antibodies in dogs from a municipality on the southern coast of Santa Catarina, Brazil, and its associated risk factors were conducted. Blood samples were collected from 238 dogs, and a questionnaire was used to gather relevant information about the dogs, including their age, gender, breed, housing and habits. The serum samples were then subjected to indirect fluorescent antibody test (IFAT) using a cutoff of 1:64 and 1:50 to detect antibodies against T. gondii and N. caninum, respectively. The study's findings revealed that the frequency of T. gondii was 23.1% (55/238), and no factors associated with infection in these animals were identified. However, the frequency of N. caninum was 4.2% (10/238), and the study identified the type of housing and environment in which the dogs lived as the factors that were associated with the infection. Stray animals and those that lived exclusively outdoors had a greater frequency of N. caninum. These results indicate that dogs from Laguna, Santa Catarina, Brazil, are exposed to T. gondii and N. caninum. As such, further studies are necessary to enhance the understanding of the nature of these protozoan infections in the municipality.

Herd-level prevalence of bovine leukemia virus, Salmonella Dublin and Neospora caninum in Alberta, Canada, dairy herds using ELISA on bulk tank milk samples.

Endemic infectious diseases remain a major challenge for dairy producers worldwide. For effective disease control programs, up-to-date prevalence estimates are of utmost importance. The objective of this study was to estimate the herd-level prevalence of bovine leukemia virus (BLV), Salmonella Dublin, and Neospora caninum in dairy herds in Alberta, Canada using a serial cross-sectional study design. Bulk tank milk samples from all Alberta dairy farms were collected 4 times, in December 2021 (n = 489), April 2022 (n = 487), July 2022 (n = 487), and October 2022 (n = 480), and tested for antibodies against BLV, S. Dublin, and N. caninum using ELISAs. Herd-level apparent prevalence was calculated as positive samples divided by total tested samples at each time point. A mixed effect modified Poisson regression model was employed to assess the association of prevalence with region, herd size, herd type, and type of milking system. Apparent prevalence of BLV was 89.4, 88.7, 86.9 and 86.9% in December, April, July, and October, respectively, whereas for S. Dublin apparent prevalence was 11.2, 6.6, 8.6, and 8.5%, and for N. caninum apparent prevalence was 18.2, 7.4, 7.8, and 15.0%. For BLV, S. Dublin and N. caninum, a total of 91.7, 15.6, and 28.1% of herds, respectively, were positive at least once, whereas 82.5, 3.6, and 3.0% of herds were ELISA-positive at all 4 times. Compared with the north region, central Alberta had a high prevalence (prevalence ratio (PR) = 1.13) of BLV-antibody positive herds, whereas south Alberta had a high prevalence (PR = 2.56) of herds positive for S. Dublin antibodies. Furthermore, central (PR = 0.52) and south regions (PR = 0.46) had low prevalence of N. caninum-positive herds compared with the north. Hutterite colony herds were more frequently BLV-positive (PR = 1.13) but less frequently N. caninum-positive (PR = 0.47). Large herds (>7,200 L/day milk delivered ∼ > 250 cows) were 1.1 times more often BLV-positive, whereas small herds (≤3,600 L/day milk delivered ∼ ≤ 125 cows) were 3.2 times more often N. caninum-positive. For S. Dublin, Hutterite-colony herds were less frequently (PR = 0.07) positive than non-colony herds only in medium and large stratum but not in small stratum. Moreover, larger herds were more frequently (PR = 2.20) S. Dublin-positive than smaller herds only in non-colony stratum but not in colony stratum. Moreover, N. caninum prevalence was 1.6 times higher on farms with conventional milking systems compared with farms with an automated milking system. These results provide up-to-date information of the prevalence of these infections that will inform investigations of within-herd prevalence of these infections and help in devising evidence-based disease control strategies.

A 20-year serological survey of Toxoplasma gondii and Neospora caninum infection in dogs with neuromuscular disorders from urban areas in Argentina.

Toxoplasma gondii and Neospora caninum infections may be associated with neuromuscular disorders in dogs. The aim of this study was to assess the seroprevalence to these protozoan parasites in dogs with neuromuscular disease from urban areas of Buenos Aires province, Argentina, over a period of 20 years, and to evaluate the association of seropositivity and antibody titres with different variables such as sex, breed and age. For this, a total of 7238 serum samples from urban owned dogs were analysed by the indirect fluorescence antibody test (IFAT) for specific IgG antibodies. The observed seropositivity rates were 35.7 % for T. gondii and 25.7 % for N. caninum. Crossbred dogs had a significantly higher seroprevalence for T. gondii than purebred dogs (41 % vs. 29.3 %), while a trend towards significance was observed for N. caninum, which was slightly higher in purebred dogs (26 % vs. 23.6 %). Seroprevalence for both parasites increased with age and was higher in older animals. Regarding the distribution of specific antibody titres, the most frequent IFAT T. gondii titre found was 100 and for N. caninum it was ≥800. For toxoplasmosis, there was no association with age group, and low titres (50, 100 and 200) predominated in all groups. However, for neosporosis, age and titres were significantly associated for one age group, with dogs under 12 months of age having a higher proportion of high titres (400 and 800). The trend in the seroprevalence for T. gondii is increasing over the years and lower antibody titres predominate in the dogs studied, which may be more related to the presence of chronic infections and not necessarily to the clinical signs of the animals. Despite the generally low titres observed for toxoplasmosis in this study, it is important to highlight the high seroprevalence found in our region, as dogs can act as sentinels of environmental contamination and as indicators of possible human infection. In the case of neosporosis, although the trend in seroprevalence in dogs with signs appears to be decreasing over the years, our work shows that higher antibody titres predominate, and are probably related to the clinical signs presented by the dogs. This study provides the most recent epidemiological data and serological profiles of T. gondii and N. caninum infections in a large number of canine sera from urban areas in Argentina, providing relevant information for clinical veterinarians and epidemiologists in order to understand the circulation of the parasites.

A first insight into seropositivity of Neospora caninum and associated risk factors in free-roaming dogs from Ecuador.

Neosporosis is a worldwide parasitic disease caused by the protozoan Neospora caninum. It can cause economic losses to farmers due to its relationship with abortions and neonatal mortality in cows. Dogs play a key role in its spread as they are considered definitive hosts. In this study, we determined for the first time the seropositivity of N. caninum infection in dogs from Ecuador and evaluated potential risk factors. A total number of 339 free-roaming dogs from the three main regions of Ecuador (Coastal, Andean, and Amazonian regions) were included in the study and classified either as urban or rural dogs. Serum samples were collected from November 2018 to May 2019, and analyzed with a commercial ELISA test. An overall seropositivity of 6.8 % (CI: 95 %, 2.8 % - 11.7 %) was found in N. caninum infection with no statistical differences among regions or urban/rural dogs. This is the first surveillance of N. caninum in Ecuador, confirming a country-wide distribution of this pathogen. Considering the large populations of free-roaming dogs in Ecuador, a One Health approach for surveillance and managing N. caninum in dogs is needed to protect either livestock or wildlife.

The seasonality as a relevant aspect to be considered for differential diagnosis of Trypanosoma vivax infection and co-infections in female cattle.

Bovine Trypanosomiasis and other infectious diseases cause relevant loss for the livestock industry impacting productive/reproductive indices. This study intended to better understand the frequency, seasonality, and profile of infections associated with Bovine Trypanosomiasis. A total of 1443 serum samples were screened for T. vivax infection and other infectious diseases: Neosporosis, Leptospirosis, Bovine Leukosis Virus infection/(BLV), Infectious Bovine Rhinotracheitis/(IBR) or Bovine Viral Diarrhea/(BVD). Distinct methods were used for screening and diagnosis: immunofluorescence assay (Trypanosomiasis), ELISA (Neosporosis,BLV,IBR,BVD) and microscopic agglutination test (Leptospirosis). Our findings demonstrated that the seropositivity for Trypanosomiasis=57% was similar to Neosporosis=55%, higher than Leptospirosis=39% and BVL=34%, but lower than IBR=88% and BVD=71%. The seropositivity for Trypanosomiasis was higher in the autumn and lower in the winter. Regardless the season, the IBR seropositivity (min=73%;max=95%) was higher than Trypanosomiasis (min=48%;max=68%). Moreover, Neosporosis (min=71%;max=100%) and BVD (min=65%;max=76%) were more frequent than Trypanosomiasis in the summer, winter and spring. The diagnosis outcome revealed that Trypanosomiasis&IBR=43% and Trypanosomiasis&Neosporosis=35% were the most frequent co-infections with higher seropositivity in the autumn (58%) and summer (80%), respectively. Noteworthy, high seropositivity to Trypanosomiasis&BVD was registered in the autumn (46%). Together, our data re-enforce the relevance of differential diagnosis between Trypanosomiasis with other bovine infectious diseases and that differences in the seasonality profile is a relevant aspect to be considered while selecting the differential diagnosis to be applied.

Neospora caninum antibodies in bulk tank milk from dairy cattle herds in Italy in relation to reproductive and productive parameters and spatial analysis.

Among the available diagnostic techniques, antibody detection in bulk tank milk (BTM) represents a useful tool to estimate and monitor Neospora caninum herd prevalence. To evaluate the prevalence of N. caninum and the effect of parasite infection on herd performances, BTM samples collected from 586 dairy herds located in one of the largest dairy production areas in Italy (Lombardy) were analyzed by an indirect ELISA to detect anti-N. caninum specific antibodies. Generalized linear models (GLMs) were developed. A purely spatial analysis scanning for clusters with high or low rates for N. caninum using the Bernoulli model was performed. A maximum entropy approach was used to estimate the probability of distribution of the parasite based on occurrence records together with environmental variables. Overall, 180 herds resulted positive for N. caninum antibodies on bulk tank milk (P = 30.7 %). A higher risk of seropositivity was evidenced in the provinces of Milano, Cremona, Brescia, and Bergamo (P = 32-40 %); a lower risk was evidenced in Lodi, Pavia, and Mantova (P = 13-24 %). A higher risk of seropositivity was revealed for small-medium farms (101-300 animals) (O.R.=2.8) and for older animals with more than 4 years (O.R.=4.4). Regarding the effect of N. caninum infection on herd performances, the number of inseminations for conception was higher (> 3 inseminations), and the period from calving to conception was longer (> 150 days) for positive farms (O.R.=2.0 and O.R.=2.3, respectively); besides, lower head daily milk production (<20 kg and 21-25 kg) and mature equivalent milk yield (<11,000), and somatic cell counts higher than 300,000 cells/ml were observed for N. caninum positive herds (O.R.=0.4, O.R.=0.4 and O.R.=1.9 respectively). The geographical distribution of N. caninum positive farms with the highest level of probability covers the central sector of the Po Plain where a significant cluster for high risk of parasite infection was shown by spatial scan statistic and Maximum entropy ecological niche modelling. A further significant cluster of low risk occurred in the southern. The climatic and environmental variables with the highest training gain when used in isolation resulted altitude, land use/land cover, and other variables related to temperature and precipitation. Neosporosis is widely distributed in Italian dairy herds and an impact of the parasite on herd performances could be hypothesized. Even if the role of N. caninum in alterations of reproductive and productive parameters should be further explored, veterinarians and farmers should be aware of neosporosis, and control plans should be adopted.

Seroprevalence of Toxoplasma gondii and Neospora caninum in family farming goats from the Luracatao Valley, Salta, Argentina.

Toxoplasma gondii and Neospora caninum infections are important causes of abortion in ruminants. The objective of this study was to determine the seroprevalence and frequency of T. gondii and N. caninum titers in goats raised by family farmers in the Luracatao Valley of Salta province, Argentina. A total of 259 serum samples were collected from adult goats in 42 family farms in nine communities and tested for indirect fluorescent antibody test (IFAT, cut-off 1:100). Seroprevalences were 34.36% (89/259) for T. gondii and 64.09% (166/259) for N. caninum. Co-infection was found in 25.86% (67/259) of the goats tested. The most frequent IFAT titer of T. gondii found was 100 (23.93%; 62/259), and only 2% (5/259) of the goats presented titer 800. For N. caninum, the most frequent titers were 100 (25.86%; 67/259), and titers 200 (20.46%; 53/259) and 400 (14.61%, 38/259). The titers found for T. gondii could suggest a chronic infection in goats, being of importance for the region due to meat consumption and cheese production. The elevated seroprevalence of N. caninum identified in this study may be attributed to the community-specific dog population and the close interaction between dogs and goats, despite the absence of a statistically significant association. Subsequent research is warranted to assess the productive implications of T. gondii and N. caninum.

Macrophage migration inhibitory factor favors Neospora caninum infection in mice.

Neospora caninum is a protozoan parasite with worldwide incidence, acting as a major cause of reproductive failures in ruminants and neuromuscular symptoms in dogs. Macrophage Migration Inhibitory Factor (MIF) is produced by several cell types and exhibits a central role in immune responses against intracellular pathogens. The present study aimed to comprehend the role of MIF in the relationship between N. caninum and its host. We used in vivo, in vitro and ex vivo experiments in a model of infection based on genetically deficient mice to analyze the infection kinetics and inflammatory markers. MIF production was measured in response to N. caninum during the acute and chronic phases of the infection. While Mif-/- mice survived lethal doses of NcLiv tachyzoites, sublethal infections in these mice showed that parasite burden was controlled in target tissues, alongside with reduced inflammatory infiltrates detected in lung and brain sections. TNF was increased at the initial site of the infection in genetically deficient mice and the MIF-dependent reduction was confirmed in vitro with macrophages and ex vivo with primed spleen cells. In sum, MIF negatively regulated host immunity against N. caninum, favoring disease progression.

Evaluation of Immunodiagnostic Performances of Neospora caninum Peroxiredoxin 2 (NcPrx2), Microneme 4 (NcMIC4), and Surface Antigen 1 (NcSAG1) Recombinant Proteins for Bovine Neosporosis.

Bovine neosporosis is among the main causes of abortion in cattle worldwide, causing serious economic losses in the beef and dairy industries. A highly sensitive and specific diagnostic method for the assessment of the epidemiology of the disease, as well as it surveillance and management, is imperative, due to the absence of an effective treatment or vaccine against neosporosis. In the present study, the immunodiagnostic performance of Neospora caninum peroxiredoxin 2 (NcPrx2), microneme 4 (NcMIC4), and surface antigen 1 (NcSAG1) to detect IgG antibodies against N. caninum in cattle were evaluated and compared with that of the indirect fluorescent antibody test (IFAT). The results revealed that NcSAG1 had the highest sensitivity and specificity, with values of 88.4% and 80.7%, respectively, followed by NcPrx2, with a high sensitivity of 87.0% but a low specificity of 67.0%, whereas NcMIC4 showed sensitivity and specificity of 84.1% and 78.9%, respectively, when compared with IFAT. A high degree of agreement was observed for NcSAG1 (k = 0.713) recombinant protein, showing the highest diagnostic capability, followed by NcMIC4 (k = 0.64) and NcPrx2 (k = 0.558). The present study demonstrates that NcSAG1 is helpful as an antigen marker and also demonstrates the potential immunodiagnostic capabilities of NcPrx2 and NcMIC4, which could serve as alternative diagnostic markers for detecting N. caninum infection in cattle. These markers may find utility in future treatment management, surveillance, and risk assessment of neosporosis in livestock or other animal host species. Further research should be directed toward understanding the in vivo immune response differences resulting from immunization with both recombinant proteins.

Seroprevalence of Toxoplasma gondii, Neospora caninum and Trichinella spp. in Pigs from Cairo, Egypt.

Pork production is a niche economy in Egypt, and pigs are typically raised as backyard animals with no sanitary control, potentially exposing them to various pathogens. Commercially available ELISAs were used to detect specific antibodies to the food-borne zoonotic parasites Toxoplasma gondii and Trichinella spp., as well as to Neospora caninum, in serum samples of pigs slaughtered at Egypt's only licensed pig abattoir, the El-Bassatin abattoir in Cairo. Among the tested sera (n = 332), seroreactivity for T. gondii was 45.8% (95% confidence interval: 40.4-51.3), N. caninum was 28.0% (95% CI: 23.3-33.2), and Trichinella spp. was 1.2% (95% CI: 0.4-3.3). Mixed infection was only detected for T. gondii and N. caninum (18.7%; 95% CI: 14.7-23.4). The seroprevalence of T. gondii was significantly higher (p = 0.0003) in animals collected from southern Cairo (15 May city slum) than in eastern Cairo (Ezbet El Nakhl slum). Seroprevalence for N. caninum was higher in western (Manshiyat Naser slum; p = 0.0003) and southern Cairo (15 May city slum; p = 0.0003) than in that of eastern Cairo (Ezbet El Nakhl slum; p = 0.0003). Moreover, female pigs exhibited a higher rate of N. caninum antibodies than male ones (p < 0.0001). This study provides the first seroprevalence data for N. caninum in pigs in Egypt, and updates the prevalence of the zoonotic parasites Trichinella spp. and T. gondii.

Evaluation of frequency of antibodies against Neospora caninum, Toxoplasma gondii and Brucella melitensis, risk factors and spatial distribution of infection in goat and sheep flocks from Argentina.

Neospora caninum, Toxoplasma gondii and Brucella melitensis are pathogens that cause abortion in small ruminants. Besides, B. melitensis and T. gondii are zoonotic pathogens. The aim of this study was to describe the frequency of antibodies against N. caninum, T. gondii and B. melitensis in sheep and goats from three provinces of the center region of Argentina. In addition, the spatial distribution of the infected flocks/herds and risk factors were evaluated. A cross-sectional study was conducted from 2015 through 2016. Serum samples from 4783 goats and 1524 sheep from 186 goat, 51 sheep and 38 mixed flocks/herds were analyzed. Competitive inhibition enzyme-linked immunosorbent assay (ciELISA) and indirect fluorescent antibody test (IFAT) were performed for detection of antibodies against N. caninum and IFAT for T. gondii. The buffered plate antigen test and complement fixation test were performed for detection of antibodies against B. melitensis. The frequency of anti-T. gondii antibodies was 41.2% and 29.7% for sheep and goats, respectively. The frequency of anti-N. caninum antibodies was 17.2% and 14% for sheep and goats, respectively. About 97.1% of the sheep flocks, 79.4% of the goat herds and the 91.3% of the mixed flocks had seropositive animals to T. gondii. About 61.8% of the sheep flocks, 58% of the goat herds and the 82.6% of the mixed flocks had seropositive animals to N. caninum. All the analyzed animals were negative to anti-B. melitensis antibodies. For T. gondii, a significant cluster of high risk of seropositive flocks/herds was detected in the littoral of the Parana River. The province of origin of the flock/herd was the only variable associated to T. gondii positivity (p = 0.003). Animals from Santiago del Estero and Santa Fe Provinces had 3.48 and 1.77 times more risk to be positive to T. gondii than animals from Entre Ríos Province, respectively. For N. caninum, a cluster of high risk of seropositive flocks/herds was detected in the north of Santa Fe Province. The only explanatory variable associated to N. caninum positivity was animal species (p = 0.003). Sheep had 1.73 times more risk to be positive to N. caninum than goats. The absence of antibodies against B. melitensis in all the analyzed animals is an important finding for the public health of the region. Since bordering provinces have infected flocks/herds, brucellosis in small ruminants should be under epidemiologic surveillance in the region.

Assessment of Neospora caninum infection in bulls using serological and molecular techniques.

Neospora caninum is a significant cause of abortion and economic losses in cattle worldwide. The main aim of the present work was to detect the prevalence of N. caninum infection in bulls in Hamedan (Iran) using serology and molecular techniques. All blood samples (n = 792) were screened for detecting the antibodies to N. caninum using enzyme-linked immunosorbent assay (ELISA). Then seropositive animals were rechecked using the immunofluorescent antibody test (IFAT). Also, blood, epididymis, and spinal cord samples were collected from animals for molecular analysis using nested PCR. In serology, using ELISA, 3.91% of animals were seropositive for N. caninum. Additionally, true prevalence based on the sensitivity and specificity of the ELISA was calculated 1.25% (95% CI: 0.48-2.02%). Neospora-infection in animals, calculated as the number of bulls seropositive and/or one sample positive to nested PCR, was 3.40%; and 19 bulls tested positive by both serology and molecular diagnostic methods. The overlaps between ELISA and molecular results were observed in 74.19% of whole blood samples, 80.64% of the epididymis, and 87.09% of the spinal cord. Using ELISA, the seroprevalence of N. caninum was detected 1.8% in ≤2 and 5.45% in >2 years old group of animals (p = 0.009, PR = 3.1). In addition, the seropositivity in Holstein and native breed animals was calculated 6.57% and 2.93%, respectively (p = 0.019, PR = 2.3). Seven sequences with 94.9-99.3% similarity were detected in multiple alignments of positive PCR products. Our work was the first comprehensive evaluation of Neospora-infection/neosporosis in Iranian bulls. We detected a low prevalence of infection in animals compared to previous reports. The ELISA is a sensitive serological technique for detecting the highest number of positive bulls in the present investigation and, the nested PCR is a reliable technique to identify Neospora-DNA.

Evidence of Australian wild deer exposure to N. caninum infection and potential implications for the maintenance of N. caninum sylvatic cycle.

Infections with the coccidian parasite Neospora caninum affect domestic and wild animals worldwide. In Australia, N. caninum infections cause considerable losses to the cattle industry with seroprevalence of 8.7% in beef and 10.9% in dairy cattle. Conversely, the role of wild animals, in maintaining the parasite cycle is also unclear. It is possible that native or introduced herbivorous species could be reservoir hosts of N. caninum in Australia, but to date, this has not been investigated. We report here the first large-scale screening of N. caninum antibodies in Australian wild deer, spanning three species (fallow, red and sambar deer). Consequently, we also assessed two commercial cELISA tests validated for detecting N. caninum in cattle for their ability to detect N. caninum antibodies in serum samples of wild deer. N. caninum antibodies were detected in 3.7% (7/189, 95% CI 1.8 - 7.45) of the wild deer serum samples collected in south-eastern Australia (n = 189), including 97 fallow deer (Dama dama), 14 red deer (Cervus elaphus), and 78 sambar deer (Rusa unicolor). Overall, our study provides the first detection of N. caninum antibodies in wild deer and quantifies deer's potential role in the sylvatic cycle of N. caninum.

An Antibody-Based Survey of Toxoplasma gondii and Neospora caninum Infection in Client-Owned Cats from Portugal.

Toxoplasma gondii and Neospora caninum are obligate intracellular protozoan parasites infecting a wide range of hosts worldwide. However, information on the epidemiology of toxoplasmosis and neosporosis in cats from Portugal is limited. Thus, this study aims to evaluate anti-T. gondii and anti-N. caninum seroprevalence in client-owned cats from Portugal and to identify risk factors using a panel of well-characterized sera. A total of 183 domestic cats were sampled and screened for antibodies against T. gondii and N. caninum using commercial ELISA assays, and their owners answered an online questionnaire designed to obtain background information. The overall anti-T. gondii and anti-N. caninum seroprevalences were 13.1% (CI: 8.97-18.77) and 3.8% (CI: 1.87-7.68), respectively. Univariate analysis revealed that living strictly indoors was a significant protection factor (cOR: 0.053; CI: 0.005-0.627), and the presence of a chronic disease a significant risk factor (cOR: 3.106; CI: 1.062-9.082) to T. gondii seroprevalence. When performing multivariate analysis, only chronic disease (aOR: 57.527; CI: 1.7-1976.7) and seropositivity to N. caninum (aOR: 7.929; CI:0.8-82.9) were found to be a significant risk factor to anti-T. gondii antibodies. To the best of our knowledge, this is the first report of N. caninum seropositivity in cats from Portugal.

Seropositivity of Anti-Toxoplasma gondii and Anti-Neospora caninum Antibodies in Cattle Intended for Human Consumption in an Amazonian Area of North Brazil.

Toxoplasma gondii and Neospora caninum are obligate intracellular intestinal coccidia distributed worldwide, and are causative agents of toxoplasmosis and neosporosis, respectively. The aim of this study was to evaluate the prevalence of anti-T. gondii and anti-N. caninum antibodies and the factors associated with infections in beef cattle intended for human consumption in an Amazonian area of North Brazil. We collected blood samples of 387 cattle from 50 herds located in different municipalities of the State of Rondônia. An epidemiological questionnaire was distributed to farmers, with regard to nutritional, sanitary and reproductive herd management. The samples were identified, refrigerated and sent for serological analyses via IFAT (Immunofluorescent Antibody Test). Among the 387 analyzed animals, 91 (23.5%; CI 95%: 18.8-27.2) were positive for anti-T. gondii antibodies, with titers varying from 1:64 (75.8%) to 1:512 (2.2%). For anti-N. caninum antibodies, only four animals (1%; CI 95%: 0-2.7) were positive, with titers ranging from 1:400 (50%) to 1:1600 (25%). We observed a significant rate of anti-T. gondii antibodies in the variables "pure breed" and "contact with free-range chickens" (p < 0.2). There were no risk factors associated with the presence of anti-T. gondii or anti-N. caninum antibodies. In conclusion, there was a high prevalence of anti-T. gondii antibodies in beef cattle intended for human consumption in the State of Rondônia, Brazil, and a low prevalence of anti-N. caninum antibodies. Longitudinal studies can better elucidate the cause of these prevalence levels and how they could be better prevented and controlled.

Global prevalence of Neospora caninum in rodents: A systematic review and meta-analysis.

BACKGROUND: Neosporosis has been considered a cause of abortion in dairy and beef cattle worldwide. Rodents are reservoir hosts for several infectious diseases. It is necessary to determine the prevalence of Neospora caninum in rodents to improve the current understanding of the transmission dynamics of Neospora as well as its life cycle and risk of transmission to livestock. Therefore, the objective of the present study was to estimate the pooled global prevalence of N. caninum in different rodent species. METHODS: Published studies on the prevalence of N. caninum in different rodent species were searched in the MEDLINE/PubMed, ScienceDirect, Web of Science, Scopus and Google Scholar and the reference lists of the retrieved articles until July 30, 2022. The eligible studies were selected using inclusion and exclusion criteria. The extracted data were verified and analysed using the random-effect meta-analysis. RESULT: For this meta-analysis, a total of 4372 rodents from 26 eligible studies were included. The global prevalence of N. caninum in rodents was estimated at 5% (95% CI 2%-9%), with the highest prevalence in Asia (12%; 95% CI 6%-24%) and lowest prevalence in America (3%; 95% CI 1%-14%) and Europe (3%; 95% CI 1%-6%). N. caninum was more prevalent in females (4%; 95% CI 2%-9%) than in males (3%; 95% CI 1%-11%). The most common diagnostic test was polymerase chain reaction (PCR) (21 studies). The pooled prevalence of N. caninum in rodents based on the diagnostic method was as follows: immunohistochemistry: 11% (95% CI 6%-20%), NAT: 5% (95% CI 4%-7%), IFAT: 5% (95% CI 2%-13%) and PCR: 3% (95% CI 1%-9%). CONCLUSION: The results of this study showed a relatively low but widespread prevalence of N. caninum infection in rodents.

Molecular Detection of Toxoplasma gondii, Neospora caninum and Encephalitozoon spp. in Vespertilionid Bats from Central Europe.

Bats may carry various viruses and bacteria which can be harmful to humans, but little is known about their role as a parasitic source with zoonotic potential. The aim of this study was to test wild bats for the presence of selected parasites: Toxoplasma gondii, Neospora caninum and microsporidia Encephalitozoon spp. In total, brain and small intestine tissues of 100 bats (52 Myotis myotis, 43 Nyctalus noctula and 5 Vespertilio murinus) were used for the DNA isolation and PCR detection of the abovementioned agents. Toxoplasma gondii DNA was detected by real-time PCR in 1% of bats (in one male of M. myotis), while all bats were negative for N. caninum DNA. Encephalitozoon spp. DNA was detected by nested PCR in 25% of bats, including three species (twenty-two M. myotis, two N. noctula and one V. murinus). Positive samples were sequenced and showed homology with the genotypes Encephalitozoon cuniculi II and Encephalitozoon hellem 2C. This is the first study on wild vespertilionid bats from Central Europe and worldwide, with a relatively high positivity of Encephalitozoon spp. detected in bats.

Epidemiological evaluation of Neospora caninum in dairy animals.

The purpose of the study is to explore the epidemiological information concerning the spread of neosporosis in the Moscow region (Russian Federation) and Almaty region (Republic of Kazakhstan). The study is conducted in 2019 in the Moscow region (Russian Federation) and Almaty region (Republic of Kazakhstan). The study sample includes 800 cows (400 animals at each of the two locations), 100 at each of the 4 cattle farms in the Moscow region and 100 at each of the 4 cattle farms in the Almaty region. There were more seropositive cows on the rest of farms as compared to farm No. 1: 1.9 times more on farm No. 2 (p ≤ 0.01), 2.4 times more on farm No. 3 (p ≤ 0.001), and almost 4 times more on farm No. 4 (p ≤ 0.0001). In terms of the abortion rates, the maximum difference between the farms was 5-fold in the Moscow region (p ≤ 0.0001) and 3-fold in the Almaty region (p ≤ 0.001). Positive correlations exist between all the studied parameters (the proportion of seropositive animals, the proportion of seroprevalent animals, the abortion rate, and the stillbirth rate). The results of the study are mainly extremely valuable for the global economy, because the Republic of Kazakhstan and the Russian Federation occupy an important place in the export of meat and dairy products.

Anti-Toxoplasma gondii and Anti-Neospora caninum Antibodies in Urban Traction Equids in Northeast Brazil: Seroprevalence and Risk Factors.

The aim of this study was to describe the prevalence of anti-T. gondii and anti-N. caninum antibodies in equids that carry out traction work in Northeastern Brazil, and to establish the potential risk factors associated with seropositivity for these agents. Blood samples were collected from 322 traction equids (horses, donkeys and mules) in urban areas of 16 municipalities in the State of Paraíba, Brazil. The samples were sent for serological diagnosis using the Immunofluorescence Antibody Test (IFAT). Epidemiological questionnaires were given to the owners to assess the possible risk factors associated with infections. It was observed that 13.7% (44/322, CI: 10.9-16.5) of the equids tested positive for anti-T. gondii antibodies and 5% (16/322, CI: 2.6-7.4) tested positive for anti-N. caninum antibodies. Conducting traction work for over four years was considered a risk factor associated with T. gondii infection (odds ratio: 6.050; CI: 4.38-8.54, p = 0.025). There were no risk factors associated with N. caninum infection. It was concluded that traction equids have a significant prevalence of anti-T. gondii and anti-N. caninum antibodies in urban areas in the State of Paraíba, with an identified risk factor for seropositivity for anti-T. gondii as conducting traction work for more than four years.