Potential distribution modelling for Haemonchus contortus (Nematoda: Trichostrongylidae) in South America.

The species Haemonchus contortus occurs in many regions worldwide, mainly parasitising small ruminants and economically impacting animal production. Climate change is considered a driving force for the risk of diseases caused by helminths and can also affect relationships between parasites and their hosts, with the potential to cause losses in both animal production and biodiversity in general. The aim of this study was to model the potential distribution of H. contortus in South America. We used MaxEnt to perform the analyses and describe the contribution of important bioclimatic variables involved in the species distribution. Our results show that H. contortus colonised most of the areas with habitats that suit the species' environmental requirements and that this parasite presents habitat suitability in a future scenario. Understanding the effects of climate change on the occurrence and distribution of parasite species is essential for monitoring these pathogens, in addition to predicting the areas that tend to present future parasite outbreaks and identify opportunities to mitigate the impacts of the emergence of diseases caused by these organisms.

A systematic literature review and meta-analysis of Toxoplasma gondii seroprevalence in goats.

The aim of this study was evaluate to seroprevalence of Toxoplasma gondii in goats worldwide and the main risk factors associated from 2000 to 2020, through meta-analysis with 55,317 goats from 75 reports published in seven electronic databases of major global importance. A global seroprevalence detected was 27.49% (95% CI 24.15-30.95; I2 = 99%), with the lowest percentage in Asia (20.74%; 95% CI 16.45-25.39) and highest in Central America (62.15%; 95% CI 57.28-66.90) and Europe (31.53%; 95% CI 21.71-42.26). The seropositivity in Africa and South America were (29.41%; 95% CI 19.11-40.89) and (29.76%; 95% CI 25.84-33.83), respectively. The seroprevalence was associated with presence of cats (OR 2.22; 95% CI 1.30-3.82), goats older than one year (OR 1.77; 95% CI 1, 37-2.29), females (OR 1.43; 95% CI 1.23-1.65), rearing system (extensive vs. intensive) (OR 4.82; 95% CI 1.96-11, 84) and rearing system (semi-intensive vs. intensive) (OR 1.48; 95% CI 1.48-6.13). The heterogeneity was evidenced in most world regions and the risk factors may play roles in varying the seroprevalence.

Seroprevalence of Neospora caninum and risk factors associated with infection in water buffaloes (Bubalus bubalis) from Maranhão State, Brazil.

The aim of this work was to determine the seroprevalence of Neospora caninum in buffaloes (Bubalus bubalis) from Maranhão State, Brazil, and identify risk factors associated with infection. In total, 338 buffaloes of different ages and both sexes from four farms were randomly selected. Information about the study region, animals and management was collected using an epidemiological questionnaire. Sera were subjected to an indirect fluorescent antibody test (IFAT) to detect anti-N caninum antibodies, while N. caninum DNA was detected using the polymerase chain reaction (PCR) assays. The overall seroprevalence of N. caninum in buffaloes was 27.5% (93/338), while DNA was detected in 3.0% (3/101) samples. The proportion of positive animals detected by IFAT and PCR simultaneously was 2.6% (2/77). The risk factors for N. caninum infection were contact with fomites (p = 0.022), management conditions (p = 0.005), calving interval of 20 months (p = 0.010) and deworming management (application 3 times a year in adults and calves, p = 0.020; change of anthelmintic group, p = 0.040). By multivariate analysis, management conditions was a risk factor for N. caninum infection with odds ratio of 2.2 (95% CI 1.0-4.6). This is the first report of the prevalence and risk factors for neosporosis in B. bubalis of Maranhão State, Brazil. Thus, N. caninum is widely distributed in buffalo herds in Maranhão, with management conditions being a risk factor for infection. Further studies should be conducted to elucidate the importance of buffaloes in the epidemiology of neosporosis in Maranhão State.

Seroprevalence and risk factors for Neospora caninum and Toxoplasma gondii in goats of Maranhão State, Brazil.

We estimated the seroprevalence and possible risk factors for neosporosis and toxoplasmosis in goats in the state of Maranhão, Brazil. In addition, the variables related to these animals and the management of the farm were investigated in terms of the significance of the associations. In total, 383 serum samples from goats, of both sexes and different ages, were collected from 15 farms in four municipalities. The indirect immunofluorescence test was used for antibody detection against Neospora caninum and Toxoplasma gondii. The overall seroprevalence of N. caninum in goats was 26.4% (101/382; IC 95% 22.3-31.1), and 114 out of 383 serum samples were T. gondii-seropositive (29.8%, IC 95% 25.4-34.5). In addition, the seroprevalence of coinfection of T. gondii and N. caninum in goats was 8.6% (33/382; IC 95% 6.2-11.8). The risk factors significantly associated with the seroprevalence of N. caninum were age, type of sheepfold floor, rearing system, feeding, pasture area cultivated, cats having access to the feed deposits, worming, slaughter place of the animals, history of abortion and the presence of dogs and cats. Regarding the seroprevalence of T. gondii infection, age, category, presence of other species and purpose of breeding were the risk factors. To our knowledge, this is the first report of the seroprevalence and risk factors for N. caninum and T. gondii in goats in the state of Maranhão, Brazil, which provides basic data for the implementation of strategies and control measures against neosporosis and toxoplasmosis.

In vitro assessment of the efficacy of protein exudates from seeds against Haemonchus contortus.

Nematodes develop resistance to the most common commercially available drugs. The aim of this study was to identify and evaluate the action of protein exudates from Mimosa caesalpiniifolia, Leucaena leucocephala, Acacia mangium, and Stylosanthes capitata seeds on the gastrointestinal nematode Haemonchus contortus. The exuded proteins were precipitated, dialyzed, lyophilized, and assessed for their effect on egg hatching and artificial larval exsheathment inhibition. Proteome analysis of the protein extracts was also performed. Although no egg-hatching inhibition was observed, all exudates showed efficacy in inhibiting the larval exsheathment of H. contortus larvae with an EC50 varying from 0.61 to 0.26 mg P mL-1. Proteomic analysis revealed the presence of proteases, protease inhibitors, chitinases, and lectins among other proteins in the exudates. Most of the exuded proteins belong to the oxidative stress/plant defense and energy/carbohydrate metabolism functional clusters. This study concluded that the bioactive proteins from different classes exuded by seeds of M. caesalpiniifolia, L. leucocephala, A. mangium, and S. capitata show stage-specific inhibition against H. contortus.

A systematic literature review and meta-analysis of risk factors for Neospora caninum seroprevalence in goats.

This meta-analysis aimed to estimate N. caninum seroprevalence in goats worldwide to determine the main risk factors for seropositivity that could be associated with parasite infection in herds. Four electronic databases were searched: PubMed, SciELO, Scopus and the VHL Regional Portal. Firstly, 367 articles were identified. After removing duplicates and non-eligible papers. A total of 36 articles were selected, which contained information concerning 22,234 goats, between 2004-2019. The combined seroprevalence of infection using a meta-analysis of the random effects model was 5.99 % (95 %, CI 4.38-7.83). The overall estimated N. caninum seroprevalence showed high heterogeneity, I2 = 97 %. The present study showed that seropositive goats were 3.07 times more likely to abort (OR 3.07; 95 % CI 1.02-9.22) than seronegative animals. The presence of dogs on farms also increased the odds of N. caninum seropositivity (OR 1.40; 95 % CI 1.01-1.94). In addition, male animals had higher odds of being seropositive to neosporosis than females (OR 1.31; 95 % CI 1.00-1.71). N. caninum seroprevalence in goats is widely distributed worldwide, with the American continent having a higher proportion of seropositive animals.

Protection against Toxoplasma gondii cysts in pigs immunized with rROP2 plus Iscomatrix.

This study aimed to evaluate the humoral immune response in pigs immunized intranasally and intramuscularly with recombinant Toxoplasma gondii rROP2 protein in combination with the adjuvant Iscomatrix. Twelve mixed breed pigs divided into three groups (n=4) were used, G1 received recombinant ROP2 proteins (200 µg/dose) plus Iscomatrix, G2 received PBS plus Iscomatrix, and G3 as the control group. The intranasal (IN) and intramuscular (IM) routes were used. Animals were challenged orally with VEG strain oocysts and treated on day three after challenge. Fever, anorexia, and prostration were the clinical signs observed in all animals. All the G1 animals produced antibodies above the cut-off on the day of the challenge, while the G2 and G3 remained below the cut-off. Better partial protection against parasitemia and cyst tissue formation was observed in G1 than G3. The protection factors against tissue cyst formation were 40.0% and 6.1% for G1 and G2, respectively, compared to G3. In conclusion, there were not systemic antibody responses in pigs with IN immunization with rROP2+Iscomatrix; however, after IM immunization, those animals produced higher titers than animal controls. We associated these results with partial protection obtained against parasitemia and tissue cysts formation.

Survey of Neospora caninum in eared doves (Zenaida auriculata) in Southern Brazil.

Neosporosis is an infectious disease caused by Neospora caninum, a protozoan parasite that has worldwide distribution and is responsible for enormous economic losses in cattle. Birds are considered a good bioindicator of environmental contamination, since they feed on the ground, being exposed to N. caninum oocysts. The aim of this study was to determine the occurrence of antibodies against N. caninum and to verify the presence of parasite DNA in brain from free-ranging eared doves (Zenaida auriculata) from Southern Brazil. For this purpose, blood and brain samples were collected from 249 doves for ELISA and PCR analysis respectively. The prevalence of N. caninum antibodies in doves was 31.72% (79/249) and detection of parasite DNA was not observed in none of birds. This is the first report of antibodies against N. caninum in doves Z. auriculata, what show us that these birds had previously contact with the parasite but since no N. caninum DNA was detected, more studies should be performed to elucidate the real importance of doves in the epidemiologic cycle of the N. caninum.

rROP2 from Toxoplasma gondii as a potential vaccine against oocyst shedding in domestic cats.

The aim of the present study was to evaluate oocyst shedding in cats immunized by nasal route with T. gondii proteins ROP2. Twelve short hair cats (Felis catus) were divided in three groups G1, G2 and G3 (n=4). Animals from G1 received 100 µg of rROP2 proteins plus 20 µg of Quil-A, G2 received 100 µg of BSA plus 20 µg of Quil-A, and the G3 only saline solution (control group). All treatments were done by intranasal route at days 0, 21, 42, and 63. The challenge was performed in all groups on day 70 with ≅ 800 tissue cysts of ME-49 strain by oral route. Animals from G1 shed less oocysts (86.7%) than control groups. ELISA was used to detect anti-rROP2 IgG and IgA, however, there were no correlation between number of oocyst shedding by either IgG or IgA antibody levels. In the present work, in spite of lesser oocysts production in immunized group than control groups, it was not possible to associate the use of rROP2 via nostrils with protection against oocyst shedding. For the future, the use of either other recombinant proteins or DNA vaccine, in combination with rROP2 could be tested to try improving the efficacy of this kind of vaccine.

rROP2 from Toxoplasma gondii as a potential vaccine against oocyst shedding in domestic cats / rROP2 de Toxoplasma gondii como potencial vacina contra a eliminação de oocistos em gatos domésticos

Abstract The aim of the present study was to evaluate oocyst shedding in cats immunized by nasal route with T. gondii proteins ROP2. Twelve short hair cats (Felis catus) were divided in three groups G1, G2 and G3 (n=4). Animals from G1 received 100 μg of rROP2 proteins plus 20 μg of Quil-A, G2 received 100 μg of BSA plus 20 μg of Quil-A, and the G3 only saline solution (control group). All treatments were done by intranasal route at days 0, 21, 42, and 63. The challenge was performed in all groups on day 70 with ≅ 800 tissue cysts of ME-49 strain by oral route. Animals from G1 shed less oocysts (86.7%) than control groups. ELISA was used to detect anti-rROP2 IgG and IgA, however, there were no correlation between number of oocyst shedding by either IgG or IgA antibody levels. In the present work, in spite of lesser oocysts production in immunized group than control groups, it was not possible to associate the use of rROP2 via nostrils with protection against oocyst shedding. For the future, the use of either other recombinant proteins or DNA vaccine, in combination with rROP2 could be tested to try improving the efficacy of this kind of vaccine.

Resumo O objetivo do presente estudo foi avaliar a eliminação de oocistos de Toxoplasma gondii em gatos imunizados pela via nasal com proteínas ROP2 de T. gondii. Doze gatos sem raça definida (Felis catus) foram divididos em três grupos experimentais G1, G2 e G3 (n = 4). Os animais do G1 receberam 100 μg de proteínas de rROP2 mais 20 μg de Quil-A, G2 recebeu 100 μg de albumina de soro bovino (BSA) junto com 20 μg de Quil-A, e o G3 recebeu apenas solução salina (grupo de controle). Todos os tratamentos foram realizados pela via intranasal nos dias 0, 21, 42 e 63. O desafio foi realizado em todos os grupos no dia 70 com aproximadamente 800 cistos de tecido da cepa ME-49 por via oral. Os animais de todos os grupos tiveram as suas fezes examinadas e o número de oocistos foi determinado durante 20 dias após o desafio. Os animais de G1 eliminaram menos oocistos (86,7%) do que os grupos controles. O ELISA foi utilizado para detectar IgG e IgA anti-rROP2, no entanto, não houve correlação entre o número de eliminhação de oocistos com os níveis de anticorpos IgG ou IgA. No presente trabalho, apesar da menor produção de oocistos no grupo imunizado (G1) em relação aos grupos controles (G2 e G3), não foi possível associar o uso de rROP2 pela via nasal com proteção contra eliminação de oocistos de T. gondii. Para o futuro, a utilização de outras proteínas recombinantes, ou mesmo vacina de DNA, em combinação com rROP2 poderia ser utilizada para tentar melhorar a eficácia deste tipo de vacina.

Genetic characterization of Toxoplasma gondii isolates from eared doves (Zenaida auriculata) in Brazil.

Eared doves (Zenaida auriculata), which are common in urban, rural and wild areas in many regions of Brazil, are frequently prey for domestic cats. Therefore Toxoplasma gondii isolates obtained from doves may reflect greater environmental diversity than those from other hosts. The aim of the present study was to evaluate T. gondii seroprevalence, isolate and genotype strains from Z. auriculata. Serum and tissue samples were collected from 206 doves for use in the modified agglutination test (MAT) and mouse bioassay. The prevalence of T. gondii antibodies in the doves was 22.3% (46/206), with titers ranging from 16 to 4096, and T. gondii strains were isolated from 12 of these doves. Five genotypes were detected by means of PCR-RFLP, including ToxoDB genotypes #1, #6, #17 and #65, and one genotype that had not previously been described (ToxoDB#182). This was the first report on isolation of T. gondii from Z. auriculata. This study confirmed the genetic diversity of T. gondii isolates and the existence of clonal type II (ToxoDB genotype #1) in Brazil.

Genetic characterization of Toxoplasma gondii isolates from eared doves (Zenaida auriculata) in Brazil / Caracterização genética de isolados de Toxoplasma gondii de pombos (Zenaida auriculata) no Brasil

Eared doves (Zenaida auriculata), which are common in urban, rural and wild areas in many regions of Brazil, are frequently prey for domestic cats. Therefore Toxoplasma gondii isolates obtained from doves may reflect greater environmental diversity than those from other hosts. The aim of the present study was to evaluate T. gondii seroprevalence, isolate and genotype strains from Z. auriculata. Serum and tissue samples were collected from 206 doves for use in the modified agglutination test (MAT) and mouse bioassay. The prevalence of T. gondii antibodies in the doves was 22.3% (46/206), with titers ranging from 16 to 4096, and T. gondii strains were isolated from 12 of these doves. Five genotypes were detected by means of PCR-RFLP, including ToxoDB genotypes #1, #6, #17 and #65, and one genotype that had not previously been described (ToxoDB#182). This was the first report on isolation of T. gondii from Z. auriculata. This study confirmed the genetic diversity of T. gondii isolates and the existence of clonal type II (ToxoDB genotype #1) in Brazil.

Pombos silvestres (Zenaida auriculata), comuns em áreas urbanas, rurais e selvagens em muitas regiões do Brasil, são frequentemente predados por gatos domésticos. Sendo assim, os isolados de T. gondii obtidos de pombos podem refletir uma maior diversidade ambiental do que os outros hospedeiros. O objetivo do presente estudo foi avaliar a soroprevalência, isolar e genotipar T. gondii de Z. auriculata. Amostras de soro e tecido foram coletadas de 206 pombos para o teste de aglutinação modificado (MAT) e o bioensaio em camundongos. A prevalência de anticorpos contra T. gondii em pombos foi 22,3% (46/206), com títulos variando de 16 a 4096, e T. gondii foi isolado de 12 pombos. Cinco genótipos foram detectados por PCR-RFLP, incluindo os genótipos ToxoDB #1, #6, #17, #65 e um genótipo não descrito anteriormente (ToxoDB#182). Esse é o primeiro relato de isolamento de T. gondii de Z. auriculata. Este estudo também confirmou a diversidade dos isolados de T. gondii e a presença de tipo clonal II (ToxoDB #1) no Brasil.

Neospora caninum: evaluation of vertical transmission in slaughtered dairy cows (Bos taurus).

Neospora caninum is a worldwide parasite recognized as one of the main parasites responsible for abortion in cattle. The objective of this study was to evaluate vertical transmission of N. caninum in dairy cows (Bos taurus) that were slaughtered at an abattoir in the state of Santa Catarina, southern Brazil. Blood samples (with and without EDTA) from 60 pregnant dairy cows and blood and tissue samples (brain, lung, heart and liver) from their fetuses were collected and used for PCR and serological evaluation. Blood samples from 60 non-pregnant cows were collected and used to detect antibodies. Anti-N. caninum antibodies were detected by indirect ELISA. Antibodies against N. caninum were observed in 41.6% (25∕60) of the pregnant cows and in 43.3% (26∕60) of the non-pregnant cows. Antibodies against the parasite were detected in sera from three fetuses (5.5%). PCR analysis revealed that 3.3% (2∕60) of the cows and 6.6% (4∕60) of the fetuses evaluated were positive for specific N. caninum primers. These positive fetuses were between 4-6 months of age. Therefore, considering PCR and serological tests to be indicative of vertical transmission in fetuses, 11.6% (7∕60) of the fetuses were infected by N. caninum during gestation.

Occurrence of gastrointestinal and renal helminths in Zenaida auriculata (Des Murs, 1847) trap-captured from Brazil.

This study aimed to determine the prevalence of gastrointestinal and renal helminths from naturally infected Zenaida auriculata captured in Londrina, Paraná State. Two hundred and one Eared doves were trapped and the gastrointestinal and renal helminths were collected and identified according to morphological structures. One hundred and sixteen (57.71%) doves were parasitized by helminths with specific prevalences for Ornithostrongylus quadriradiatus in 50 doves (24.88%), Ascaridia columbae in 47 (23.38%), Paratanaisia bragai and P. confusa in 34 (16.92%), Tetrameres fissispina in 17 (8.46%), Synhimantus nasuta in 14 (6.47%), Brachylaima mazzantii in 4 (1.99%) and Raillietina allomyodes in 2 doves (1.00%). Seventy four/201 (37.00%) birds were infected with only one species, and 96/201 (48.00%) pigeons were infected with nematodes. The association between different classes of helminths occurred in 40/201 (20.00%) animals. The results showed statistically differences between the presence of nematode (p = 0.00001) and trematode species (p ≤ 0.05) in the doves, and there was an association between the local of capture and the presence of trematodes and A. columbae (p ≤ 0.05). This study is the first to report the infection of Z. auriculata from Brazil with O. quadriradiatus, A. columbae, T. fissispina, S. nasuta, R. allomyodes, P. bragai and P. confusa.

Occurrence of gastrointestinal and renal helminths in Zenaida auriculata (Des Murs, 1847) trap-captured from Brazil / Ocorrência de helmintos gastrintestinais e renais em Zenaida auriculata (Des Murs, 1847) capturados no Brasil

This study aimed to determine the prevalence of gastrointestinal and renal helminths from naturally infected Zenaida auriculata captured in Londrina, Paraná State. Two hundred and one Eared doves were trapped and the gastrointestinal and renal helminths were collected and identified according to morphological structures. One hundred and sixteen (57.71%) doves were parasitized by helminths with specific prevalences for Ornithostrongylus quadriradiatus in 50 doves (24.88%), Ascaridia columbae in 47 (23.38%), Paratanaisia bragai and P. confusa in 34 (16.92%),Tetrameres fissispina in 17 (8.46%), Synhimantus nasuta in 14 (6.47%), Brachylaima mazzantii in 4 (1.99%) and Raillietina allomyodes in 2 doves (1.00%). Seventy four/201 (37.00%) birds were infected with only one species, and 96/201 (48.00%) pigeons were infected with nematodes. The association between different classes of helminths occurred in 40/201 (20.00%) animals. The results showed statistically differences between the presence of nematode (p = 0.00001) and trematode species (p ≤ 0.05) in the doves, and there was an association between the local of capture and the presence of trematodes and A. columbae (p ≤ 0.05). This study is the first to report the infection of Z. auriculata from Brazil with O. quadriradiatus, A. columbae, T. fissispina, S. nasuta, R. allomyodes, P. bragai and P. confusa.

O objetivo deste estudo foi determinar a prevalência de helmintos gastrintestinais e renais de Zenaida auriculata naturalmente infectados capturados em Londrina, Paraná. Duzentos e um pombos-de-bando foram capturados e os helmintos gastrintestinais e renais foram coletados e identificados de acordo com as estruturas morfológicas. Cento e dezesseis (57,71%) pombos estavam parasitados por helmintos com as seguintes prevalências: Ornithostrongylus quadriradiatus em 50 pombos (24,88%), seguido por Ascaridia columbae em 47 (23,38%), Paratanaisia bragai e P. confusa em 34 (16,92%), Tetrameres fissispina em 17 (8,46%), Synhimantus nasuta em 14 (6,47%), Brachylaima mazzantii em 4 (1,99%) e Raillietina allomyodes em 2 pombos (1,00%). Setenta e quatro/201 (37,00%) aves apresentaram-se infectadas por apenas uma espécie, e 96/201 (48,00%) pombos com nematodas. A associação entre diferentes classes de helmintos ocorreu em 40/201 (20,00%) animais. Os resultados mostraram diferenças estatísticas entre a presença de nematodas (p = 0,00001) e trematodas (p ≤ 0,05) em pombos, e houve associação entre o local de captura e a presença de trematodas e A. columbae (p ≤ 0,05). Este trabalho é o primeiro a relatar a infecção de Z. auriculata no Brasil com O. quadriradiatus, A. columbae, T. fissispina, S. nasuta, R. allomyodes, P. bragaie P. confusa.

Neospora caninum: evaluation of vertical transmission in slaughtered dairy cows (Bos taurus) / Neospora caninum: avaliação da transmissão vertical em vacas leiteiras (Bos taurus)

Neospora caninum is a worldwide parasite recognized as one of the main parasites responsible for abortion in cattle. The objective of this study was to evaluate vertical transmission of N. caninum in dairy cows (Bos taurus) that were slaughtered at an abattoir in the state of Santa Catarina, southern Brazil. Blood samples (with and without EDTA) from 60 pregnant dairy cows and blood and tissue samples (brain, lung, heart and liver) from their fetuses were collected and used for PCR and serological evaluation. Blood samples from 60 non-pregnant cows were collected and used to detect antibodies. Anti-N. caninum antibodies were detected by indirect ELISA. Antibodies against N. caninum were observed in 41.6% (25∕60) of the pregnant cows and in 43.3% (26∕60) of the non-pregnant cows. Antibodies against the parasite were detected in sera from three fetuses (5.5%). PCR analysis revealed that 3.3% (2∕60) of the cows and 6.6% (4∕60) of the fetuses evaluated were positive for specific N. caninum primers. These positive fetuses were between 4-6 months of age. Therefore, considering PCR and serological tests to be indicative of vertical transmission in fetuses, 11.6% (7∕60) of the fetuses were infected by N. caninum during gestation.

Neospora caninum é um parasita de distribuição mundial reconhecido como um dentre os principais parasitas, responsável por abortamento em bovinos. O objetivo deste estudo foi avaliar a transmissão vertical de N. caninum em vacas leiteiras (Bos taurus) que foram submetidas ao abate em matadouro no Estado de Santa Catarina, sul do Brasil. Sangue (com e sem EDTA) de 60 vacas leiteiras prenhas e amostras de sangue e tecidos (cérebro, pulmão, coração e fígado) de seus fetos foram coletados e utilizados para PCR e avaliação sorológica. Amostras de sangue de 60 vacas não-gestantes foram obtidas e utilizadas para detecção de anticorpos. A detecção de anticorpos séricos anti-N. caninum foi avaliada pelo ELISA-teste indireto. Anticorpos anti-N. caninum foram observados em 41,6% (25∕60) das vacas prenhas e em 43,3% (26∕60) das vacas não-gestantes. Três fetos (5,5%) foram soros positivos para N. caninum. Análise pela PCR revelou que 3,3% (2∕60) das vacas e 6,6% (4∕60) dos fetos avaliados foram positivos paraN. caninum. As idades dos fetos positivos eram de 4 a 6 meses. Portanto, considerando a PCR e a sorologia como indicativo de transmissão vertical em fetos, 11,6% (7∕60) dos fetos foram infectados por N. caninum durante a gestação.

Frequency and risk factors for infection by Neospora caninum in dairy farms of umuarama, Pr, Brazil / Frequência e fatores de risco para a infecção por Neospora caninum em propriedades leiteiras de umuarama, PR, Brasil / Frecuencia y factores de riesgo para la infección por Neospora caninum en propiedades lecheras de umuarama, Paraná, Brasil

Serum samples collected from dairy cattle and dogs in 15 farms in Umuarama, PR, were analyzed for the presence of anti-Neospora caninum antibodies using the indirect fluorescent antibody test. From 309 cows examined, 63 (20.4%) were positive, with titers ranging from 100 (23.8%) to 1,600 (11.1%). Three (6.1%) of 49 dogs analyzed were positive. Multivariate analysis of epidemiological factors revealed that production of food on the farm, absence of artificial insemination and access of domestic and wild animals to the facilities or to cattle feed showed significant association with positive serology in cows.

Amostras de soro coletadas de vacas leiteiras e cães em 15 fazendas de Umuarama, PR, foram analisadas para a presence de anticorpos contra Neospora caninum pela reação de imunofluorescência indireta. Das 309 vacas examinadas, 63 (20,4%) foram positivas, com títulos variando de 100 (23,8%) a 1.600 (11,1%). Três (6,1%) dos 49 cães avaliados foram positivos. A análise multivariada dos fatores epidemiológicos revelou que a produção de alimentos na fazenda, a ausência de programa de inseminação artificial e o acesso de animais domésticos e selvagens às instalações das vacas leiteiras ou ao alimento das vacas demonstraram associação significativa com a presence de anticorpos contra Neospora caninum nas vacas.

Muestras de suero colectadas de vacas lecheras y perros en 15 fincas de Umuarama, Paraná, fueron analizadas para detectar la presencia de anticuerpos contra Neospora caninum por reacción de inmunofluorescencia indirecta. De las 309 vacas examinadas, 63 (20,4%) eran positivas, con títulos variando de 100 (23,8%) a 1.600 (11,1%). Tres (6.1%) de los 49 perros evaluados fueron positivos. El análisis multivariado de los factores epidemiológicos reveló que la producción de alimentos en la granja, la ausencia de programa de inseminación artificial, el acceso de animales domésticos y silvestres en las instalaciones de las vacas lecheras o a los alimentos de las vacas, mostraron asociación significativa con presencia de anticuerpos a Neospora caninum en las vacas.

Serum occurrence of anti-Toxoplasma gondii antibodies in dairy cows slaughtered in an abattoir for human consume / Ocorrência sorológica de anticorpos contra Toxoplasma gondii em vacas leiteiras abatidas para consumo humano em abatedouro

Toxoplasma gondii is a worldwide parasite recognized as one of the main zoonosis in human beings. The present study aimed to evaluate serology of T. gondii from dairy cows slaughtered in an abattoir for human consume. Serum samples from 120 dairy cows (60 pregnant and 60 non-pregnant) were collected, and indirect fluorescent antibody test (IFAT) was performed to detect anti-T. gondii antibodies by considering positive animals with titers ≥50. Serologic results from cows showed 29.1% (35/120), which 29 (48.3%) e 6 (10,0%) were from pregnant and non-pregnant cows, respectively. This revealed a risk 8.4 times-higher of positively in pregnant than non-pregnant cows (OR=8.4, 2.91

Toxoplasma gondii é um parasito reconhecido mundialmente como o agente de uma das principais zoonoses em seres humanos. O presente estudo teve como objetivo avaliar a ocorrência de anticorpos contra T. gondii em vacas leiteiras abatidas em um matadouro para consumo humano. Amostras de soro de 120 vacas (60 prenhas e 60 não prenhas) foram coletadas e examinados pelo teste de imunofluorescência indireta (IFI). Os animais foram considerados positivos com títulos 50. Anticorpos contra T. gondii foram observados em 29.1% (35/120) dos animais, dos quais 29 (48,3%) e 6 (10,0%) eram, respectivamente, gestantes e não gestantes. As vacas gestantes apresentaram um risco 8.4 maior de soropositividade que os animais vazios (OR=8,4; 2,91

Oocyst shedding in cats vaccinated by the nasal and rectal routes with crude rhoptry proteins of Toxoplasma gondii.

During this study, cats were immunized by the intranasal and rectal routes with crude rhoptry proteins of Toxoplasma gondii admixed with Quil-A. Twenty-five domestic short hair cats divided into five groups (n=5) were used during this evaluation: G1 and G3 cats received 200 µg of the rhoptry proteins with Quil-A (20 µg) by the intranasal and rectal routes, respectively; G2 and G4 cats received bovine serum albumin (BSA, 200 µg/dose) with Quil-A (20 µg); and G5 animals served as unvaccinated controls. All treatments were performed at days 0, 21, 42, and 63. The challenge was done with 800 cysts of the ME49 of T. gondii strain at day 70 (challenge day). The serum IgG, IgM, IgA, and fecal IgA antibody levels were evaluated by using the indirect enzyme-linked immunosorbent assay (ELISA). Some animals produced antibody levels beyond cut-off; however, two animals from G1 (OD(mean)=0.308, OD(cut-off)=0.200) and three from G3 (OD(mean)=0.254) demonstrated IgG levels on being challenged, with similar results occurring in two cats from G1 to IgM (OD(mean)=0.279, OD(cut-off)=0.200). Fecal IgA levels were detected in all G1 cats (OD(mean)=0.330, OD(cut-off)=0.065), and in one cat from G3 (OD(mean)=0.167). The serum and fecal humoral immune responses did not correlate with oocyst shedding. Oocyst shedding varied from 98.4% (G1), 87.5% (G2), 53.0% (G3), to 58% (G4), and was lower than that of G5 cats. The prepatent period of cats vaccinated intranasally (G1) was reduced from 6-9.6 to 2.8 days, suggesting protection of environmental contamination, considering cats as the primary source of contamination. The intranasally and rectally administered rhoptry vaccines were able to partially protect cats against T. gondii cysts on being challenged; however, the intranasal method of vaccination yielded better results relative to the rectal route.

Isolation and genotyping of Toxoplasma gondii from pregnant dairy cows (Bos taurus) slaughtered.

The current study aimed to evaluate serology, and isolate and genotype Toxoplasma gondii strains from pregnant dairy cows, slaughtered in an abattoir for human consumption, and their fetuses. Blood from 60 pregnant dairy cows and blood and tissue samples (brain, lung, heart, and liver) from their fetuses were collected and analyzed in a mouse bioassay. Antibodies against T. gondii were observed in 48.3% of cows and 3.7% of fetuses (IFAT, titers ≥ 50 for cows and 25 for fetuses were considered positive). Fourteen fetuses (23.3%) and six cows (10.0%) were identified as positive in the bioassay. T. gondii was isolated from a blood sample of a cow older than 4 years old in the 6th month of pregnancy, and from a blood sample of a fetus in the 6th month of gestation. These isolates were identified by polymerase chain reaction (PCR) as being of T. gondii and both strains showed type II alleles for all PCR-restriction fragment length polymorphism (PCR-RFLP) markers tested. T. gondii type II strain from cattle was isolated for the first time in Brazil. The current study also showed that transplacental transmission of T. gondii naturally occurs in dairy cows (23.3%) from Southern Brazil.