RESUMO
The occurrence of antibodies to Neospora caninum and Toxoplasma gondii was determined in 400 domestic cats (Siamese, Persian, and undetermined breeds) from the Municipality of Araçatuba, Sao Paulo, Brazil, through the indirect fluorescence antibody test (IFAT). Of the 400 cats, 100 were seropositive to T. gondii (25%, titer > or =64) and 98 to N. caninum (24.5%, titer > or =16). The rate of seropositive cats for T. gondii was correlated with age (chi(2)=35.7; p<0.001), with a higher number of infected animals at older ages. Of the 219 cats younger than 1-year-old, 13.2% were seropositive for T. gondii, while 39.2% were positive in the 181 older animals. The presence of N. caninum was also correlated with age (/(2)=8.8; p<0.01), with 18.7% (41/219) and 31.5% (57/181) of positive animals at ages below and above 12-month, respectively. An association between the occurrences of both protozoa in the felines was also observed (chi(2)=19.6; p<0.001).
Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Gato/imunologia , Coccidiose/veterinária , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Brasil/epidemiologia , Doenças do Gato/epidemiologia , Gatos , Coccidiose/epidemiologia , Coccidiose/imunologia , Feminino , Masculino , Toxoplasmose Animal/imunologiaRESUMO
ABSTRACT The seroprevalence of Brucella spp. and the possible associated risk factors were estimated for 2,109 adult cows in Monte Negro county, State of Rondônia, Brazil. A questionnaire was completed for each farm where cattle were sampled. Laboratory tests were Rose-Bengal Agglutination, Standard Tube agglutination, and Mercaptoethanol. The adjusted overall prevalence of Brucella spp. seropositive cows for Monte Negro county was 15% and at least 54 herds (63%) were positive. A logistic regression analysis suggested that the herd size of more than 25 cows and the presence of pigs were significant factors associated with the seropositivity (herd size: OD = 2.8; P=0.02; presence of pigs: OD = 2.5; P =0.04). Other significant variables associated to the infection, analysed by Chi-Square were the presence of seropositivity cows with the herd that were repeat breeders and birth of weak calves (P 0.05).
RESUMO A soroprevalência e os possíveis fatores de risco para a infecção por Brucella spp. foram estimados em 2.109 vacas do Município de Monte Negro, Rondônia. De cada animal selecionado foi coletado soro sangüíneo e para as propriedades envolvidas foi preenchido um questionário. As amostras coletadas foram analisadas pelas provas de Antígeno Acidificado Tamponado corado com Rosa Bengala, Soroalgutinação Lenta em Tubos e 2-Mercaptoetanol. A prevalência total da infecção por Brucella spp. em vacas no Município de Monte Negro foi de 15%, sendo 54 (63%) fazendas com animais reagentes. A regressão logística sugeriu que rebanhos com mais de 25 vacas (OD = 2,8; P = 0,02) e a presença de suínos (OD = 2,5; P = 0,04) foram fatores associados a soropositividade dos bovinos. Outras variáveis associadas à infecção pelo teste do Qui-Quadrado foram repetição de cio e nascimento de bezerros enfermos (P 0,05).
RESUMO
A cross-sectional study was conducted to determine the seroprevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies and to investigate the risk factors related to antibodies against T. gondii and N. caninum in dogs of the city of Campina Grande, state of Paraiba, Northeast region of Brazil. For this purpose, 286 blood samples were collected from dogs during the rabies vaccination campaign, in September 2003, and on this occasion questionnaires addressing epidemiological aspects of the infections were given to each dog owner. The sera were analyzed for anti-T. gondii and anti-N. caninum antibodies by indirect fluorescent antibody tests. Of the total of 286 dogs, 129 were positive for T. gondii (titer16) with a prevalence value of 45.1% (95% CI=39.24-51.07%). For N. caninum, 24 dogs were positive (titer50), with a prevalence value of 8.4% (95% CI=5.45-12.23%). Antibodies to T. gondii and N. caninum were found simultaneously in 14 dogs (4.9%; 95% CI=2.7-8.08%). For T. gondii infection, the risk factors associated with seroprevalence was the age of the animals, with dogs older than one year presenting higher values of odds ratio, and co-habitation of cats in the household. For N. caninum infection, dogs that have street contact had higher odds of seropositivity than dogs that remained exclusively in a domestic environment.
Assuntos
Coccidiose/veterinária , Doenças do Cão/epidemiologia , Neospora/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Coccidiose/epidemiologia , Doenças do Cão/parasitologia , Cães , Prevalência , Estudos SoroepidemiológicosRESUMO
The water buffalo (Bubalus bubalis) is an important natural host for Neospora caninum. Serologic responses to N. caninum were studied in experimentally and naturally infected water buffaloes in Brazil. Antibodies were assayed by the indirect fluorescent antibody test (IFAT) using a cut off value of 1:25. Six buffaloes were each inoculated subcutaneously with 5 x 10(6) live culture-derived tachyzoites of the cattle Illinois strain of N. caninum, and two calves were kept as uninoculated controls. Post-inoculation (p.i.) blood samples were collected weekly for 8 weeks and then monthly until 1 year p.i. All inoculated buffaloes developed IFAT titers of 1:100 or more between 7 and 11 days p.i. and the titers remained elevated until 7 weeks p.i. Antibody titers peaked to 1:1600 in 1, 1:800 in 3 and 1:400 in 2, usually by 3 weeks p.i. Antibody titers declined to 1:25 or 1:50 in all the six buffaloes by 12 months p.i. IFAT titers to N. caninum remained at an undetectable level (< 1:25) in both control uninoculated buffaloes. To follow the dynamics of N. caninum antibodies, sera from 29 buffaloes and their calves were collected for 1 year and assayed for N. caninum antibodies; 23 of 29 calves were seropositive (IFAT of 1:100 or more) at 1-2 day of age. Of these 23 calves, 17 remained seropositive during the study, while six became seronegative at four (two calves), six (one calf) seven (two calves) and eight (one calf) months of age. These findings suggest a high rate of neonatal transmission of N. caninum in buffaloes.
Assuntos
Anticorpos Antiprotozoários/sangue , Búfalos/parasitologia , Coccidiose/veterinária , Neospora/imunologia , Animais , Brasil/epidemiologia , Coccidiose/sangue , Coccidiose/epidemiologia , Coccidiose/transmissão , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Injeções Subcutâneas/veterinária , Distribuição Aleatória , Estudos Soroepidemiológicos , Fatores de TempoAssuntos
Feto Abortado/parasitologia , Encéfalo/parasitologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Animais , Bovinos , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , Feminino , Neospora/genética , Reação em Cadeia da Polimerase/métodos , GravidezRESUMO
Attempts were made to isolate Neospora caninum from naturally infected water buffaloes (Bubalus bubalis) from Brazil. Brains from six buffaloes with indirect fluorescent antibodies (>1:100) to N. caninum were used to isolate the parasite by bioassay in dogs and gerbils followed by in vitro culture. Shedding of Neospora-like oocysts was noticed in dogs fed brains from three buffaloes (isolate designation NcBrBuf-1, 2 and 4). Two more isolates (NcBrBuf-3 and 5) were obtained by in vitro culture of the brains of gerbils previously infected with brains of two other buffaloes. The identity of the isolates was confirmed by biological and molecular methods. The isolates were found to be non-pathogenic to gerbils. All five isolates amplified the gene 5 amplicons using Neospora-specific PCR assay. The sequences of gene 5 fragments and the common toxoplasmatiid ITS-1 fragments were analyzed. The dynamics of oocyst production in the dogs indicate that water buffaloes are natural intermediate hosts for N. caninum. This is the first report of isolation of N. caninum from water buffaloes.