Genetic characterization of Toxoplasma gondii isolates from pigs intended for human consumption in Brazil.

This study genetically Toxoplasma gondii isolates obtained from pigs intended for human consumption in northeastern Brazil; multilocus PCR-RFLP and sequencing techniques were utilized. Bioassays were conducted using the brain and tongue of 20 pig heads purchased at butcher shops in the city of Ilheus, Bahia, Brazil. Overall, 11 T. gondii isolates designated TgPgBr06-16 were identified. Application of multilocus PCR-RFLP with seven molecular markers (SAG1, SAG2, SAG3, BTUB, C22-8, PK1 and Apico) identified six different genotypes. Isolates TgPgBr 06, 08, 11, 12, 14 and 15 were indistinguishable by this technique, forming a single genotype; the remaining isolates were characterized as distinct genotypes. However, when five genetic markers (SAG1, SAG2, SAG3, BTUB and c22-8) were employed in multilocus PCR-sequencing, all eleven strains of T. gondii were shown to be different. All isolates differed from Type I, II and III clonal genotypes using both genotyping techniques. These results demonstrate that the multilocus PCR-RFLP assay underestimated the true diversity of the T. gondii population in this study. Thus, DNA sequencing is the preferred technique to infer the genetic diversity and population structure of T. gondii strains from Brazil. Moreover, it is necessary to develop new molecular markers to group and characterize atypical T. gondii isolates from South America.

Risk factors associated with Toxoplasma gondii infection in dairy cattle, state of Rio de Janeiro / Fatores de risco associados à infecção por Toxoplasma gondii em bovinos leiteiros no estado do Rio de Janeiro

Toxoplasmosis is one of the most common parasitic zoonoses throughout the world. Infection in man and animals varies in different geographical areas influenced by many environmental conditions. Seroprevalence of Toxoplasma gondii infection in cattle in Brazil ranges from 1.03 to 71 percent. A cross-sectional survey was carried out in 58 out of 453 farms in the South Fluminense Paraiba Valley, State of Rio de Janeiro, Brazil. Over 3-year-old cattle (n=589) from dairy herds were selected for blood collection and detection of anti-T. gondii antibodies by indirect immunofluorescence reaction (IFA) with initial titration of 1:16; titers > 64 were considered positive. Univariate analysis of risk factors showed that cats in contact with cattle, cats in contact with drinking water, and number of cats were associated with T. gondii seroprevalence. Logistic regression revealed a two-fold increased risk for infection of cattle (p=0.0138) through larger number of cats (>3) compared with low numbers of cats (1-2) on the farm. In contrast, the presence of chickens was considered a protective factor (p=0.025).

Toxoplasmose é uma das mais comuns zoonoses parasitárias do mundo. Infecções em seres humanos e em animais variam nas diferentes áreas geográficas influenciadas pelas condições ambientais. A soroprevalência da infecção por Toxoplasma gondii em bovinos no Brasil varia de 1,03 a 71,0 por cento. O estudo transversal foi realizado em 58 de um total de 453 propriedades na região Sul Fluminense do estado do Rio de Janeiro. Vacas leiteiras acima de 3 anos de idade (n=589) foram selecionadas para coleta de sangue e a detecção de anticorpos anti-T. gondii foi feita pelo teste de imunofluorescência indireta (IFI) com titulação inicial de 1:16 e títulos > 64 foram considerados positivos. Após análise univariada dos fatores de risco, gatos em contato com bovinos, em contato com a água de beber dos animais e o número de gatos foram associados com a soroprevalência de T. gondii. A regressão logística demonstrou que o número maior de gatos (>3) teve um risco duas vezes maior (p=0,0138) que propriedades que tinham um número menor de gatos (1-2). Em contraste, a presença de galinhas foi considerada um fator de proteção (p=0,025).

Risk factors associated with the occurrence of Cryptosporidium parvum infection in calves / Fatores de risco associados à ocorrência de infecção por Cryptosporidium parvum em bezerros

Cryptosporidium parvum oocysts were detected in feces of dairy calves raised in Rio de Janeiro State and the risk factors involved in the infection were determined. A hundred calves aging up to 12-month-old from 13 dairy farms were sampled. Polymerase chain reaction was used to detect the presence of oocysts. The zoonotic C. parvum species was detected in 45 percent animals. Statistical risk factors analyses revealed an association between infection and animals raised in technical systems such as the use of milking equipment, milking cooler, and water trough(P<0.05).

Detectaram-se oocistos de Cryptosporidium parvum em fezes de bezerros leiteiros no estado do Rio de Janeiro e analisaram-se os fatores de risco envolvidos na infecção dos animais. Cem bezerros com idades de 0 a 12 meses, provenientes de 13 propriedades rurais, foram amostrados, e suas fezes examinadas pela reação em cadeia da polimerase para a detecção dos oocistos. A espécie zoonótica C. parvum foi detectada em 45 por cento dos animais. As análises estatísticas dos fatores de risco revelaram haver associação entre infecção e animais criados em propriedades tecnificadas, que usam ordenha mecanizada, resfriamento de leite e fazendas que continham reservatórios de água à disposição dos animais (P<0,05).

Mycological survey and ochratoxin A natural contamination of swine feedstuffs in Rio de Janeiro State, Brazil.

Mycotoxin contamination of animal feeds represents a hazard to human and animal health due to potential transmission to meat and milk. Barley by-products are alternative feeding supplies for animal production. The aims of this assay were to study the mycobiota of feedstuffs and finished swine feed, to determine the ability of Aspergillus and Penicillium isolates to produce ochratoxin A (OTA) and to evaluate OTA occurrence in these substrates. Corn, brewers' grains and finished swine feed samples were collected from different factories. Fungal counts were higher than 2.8x10(4)CFU g(-1). Fusarium, Aspergillus and Penicillium genera were isolated at high levels. A 23.7% of the isolates produced 9-116 microg kg(-1) of OTA in vitro. Corn samples (44%) were contaminated with 42-224 microg kg(-1) of OTA. Finished feed (31%) and brewers' grains samples (13%) were contaminated with 36-120 microg kg(-1) and 28-139 microg kg(-1) of OTA, respectively. This is the first scientific report on contamination by OTA-producer molds and OTA in swine feedstuffs from Brazil. The presence of OTA in raw materials and finished feed requires periodic monitoring to prevent mycotoxicoses in animal production, reduce economic losses and minimize hazards to human health.

Mycoflora of poultry feeds and ochratoxin-producing ability of isolated Aspergillus and Penicillium species.

In Brazil, commercial feedstuffs are an important component in modern animal husbandry, but there is no information available about fungal contamination and ochratoxin A (OTA) production. The aims of this study were to determine the mycoflora incidence in poultry feeds and evaluate OTA production. In addition, the ability to produce OTA by several Aspergillus and Penicillium species was investigated. A total of 96 samples of poultry feeds were collected from four factories in Rio de Janeiro. Samples were examined for total moulds, for Aspergillus and Penicillium spp. occurrence and for their relative densities on dichloran rose bengal chloramphenicol and dichloran 18% glycerol media. The capacity to produce ochratoxin A by selected Aspergillus and Penicillium species was determined by HPLC. Total mould counts were generally higher than 1 x 10(5 )CFU ml(-1). Aspergillus and Penicillium species were isolated in the highest numbers. Aspergillus flovus and Penicillium citrinum were the most prevalent species. There was a high percentage of potential OTA producers (46%). The amount of OTA produced on this substrate was enough to cause adverse effects in animals. Several strains isolated from poultry feeds were able to produce high levels of OTA on chloramphenicol yeast medium. OTA in raw materials needs to be surveyed and storage practices must be investigated to determine occurrence and establish the livestock toxicological risk in poultry feed.

Experimental toxoplasmosis in pregnant mares: a study of fetuses and placentas

Nove éguas prenhes foram inoculadas, via oral, com oocistos esporulados de T. gondii. Três éguas prenhes, näo infectadas, foram mantidas como testemunhas. O T. gondii foi encontrado na placenta, retina, esôfago, fígado, diafragma, cérebro, medula espinhal, músculo esquelético, coraçäo, pulmäo e língua de potros nascidos de éguas inoculadas. A obtençäo e T. gondi em diferentes tecidos, desses potros reforça a hipótese da transmissäo transplacentária deste protozoário em equinos