High genetic diversity in Toxoplasma gondii isolates from pigs at slaughterhouses in Paraíba state, northeastern Brazil: Circulation of new genotypes and Brazilian clonal lineages.

The consumption of raw or undercooked pig meat containing Toxoplasma gondii cysts is an important transmission route of this protozoon to animals and humans. This study aimed to serologically diagnose, isolate and genotype T. gondii from pigs slaughtered for human consumption in the state of Paraíba, northeastern Brazil. Blood and tissue samples (heart, tongue and brain) were collected from 120 pigs at slaughterhouses in the state of Paraíba. Serological examinations were performed with an indirect immunofluorescent antibody test (IFAT) with a cut-off point of 1:64. Tissues from positive animals were subjected to bioassays in mice to isolate the parasite. A total of 12.5% (15/120) of the animals were positive according to the IFAT, with titres ranging from 64 to 2048. Viable parasites were isolated in 80% (12/15) of the bioassays. The twelve T. gondii isolates obtained in this study and an additional 13 previously described isolates were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using 11 genetic markers. Additionally, microsatellite (MS) analysis was performed using 15 markers. Nineteen of the 25 isolates completely genotyped using PCR-RFLP had 12 different genotypes, six of which were newly identified. One isolate had a mixed infection. The same 18 non-mixed isolates had 16 different genotypes based on the MS analysis. Genotype #13 (Caribbean 1), which is commonly encountered in northeastern Brazil and is probably a clonal lineage circulating in this region, was the most frequent genotype detected through both the PCR-RFLP and MS analyses. These results demonstrate that T. gondii is widespread among pigs slaughtered in the state of Paraíba. The results also confirm that this parasite has high genetic diversity in this region and that non-archetypal genotypes commonly circulate between different hosts and across different regions of Brazil.

First report of typical Brazilian Toxoplasma gondii genotypes from isolates of free-range chickens (Gallus gallus domesticus) circulating in the state of Paraíba, Northeast Brazil.

This study evaluated, for the first time, the genetic diversity of Toxoplasma gondii isolates from free-range chickens from the state of Paraíba, Northeast Brazil. Tissue samples from 33 chickens from properties in five municipalities of Paraíba (Esperança, Olho d'Água, Malta, Monteiro, and Patos) were bioassayed in mice. The brains of mice infected with T. gondii cysts were used for DNA extraction and genotyping. Genotyping was performed using 11 PCR-RFLP markers and 15 microsatellite (MS) markers. Complete genotyping results were obtained for 29 isolates, with nine genotypes detected by RFLP and 15 genotypes identified by MS. Three genotypes (#273, #274, and #277) have only been recently identified from pigs in the region. Brazilian clonal types BrII and BrIII were identified from one isolate each. Clonal types I, II, and III were not detected by RFLP. Genotype #13 (Caribbean 1), detected in 48.3% (14/29) of isolates from four of the five municipalities investigated, was the most prevalent genotype in the state of Paraíba. However, the MS analysis showed that of these 14 isolates, only four were unique genotypes, and considering the distance between the municipalities from where they were collected, it is possible that only seven are independent isolates while the others are clones. The other genotypes were restricted to different microregions. The results indicate that the Caribbean 1 lineage of T. gondii is circulating widely in Northeast Brazil. The genotypic diversity of T. gondii in the state of Paraíba is high, and microsatellite analysis revealed this diversity with higher resolution than PCR-RFLP.

First study on seroepidemiology and isolation of Toxoplasma gondii in free-range chickens in the semi-arid region of Paraíba state, Brazil.

The aim of this study was to investigate the seroprevalence and isolation of Toxoplasma gondii in free-range chickens in the state of Paraíba, northeastern Brazil. For this, blood samples were collected from 483 chickens in five municipalities in the state of Paraíba. The indirect immunofluorescence assay for anti-T. gondii antibodies was performed. The seropositive birds were slaughtered, and their brains and hearts were collected in order to perform a bioassay in mice. An epidemiological questionnaire was applied on the smallholdings visited, and univariable and multivariable logistic regressions were used to evaluate risk factors. The prevalence of chickens seropositive for T. gondii was found to be 31.5 % (152/483), and 86.1 % (56/65) of the smallholdings were positive. Among the 71 chickens subjected to bioassaying in mice, isolates of T. gondii were obtained from 33 (46.5 %). The isolates were named TgCkBrPB1 to 33. It was observed that the higher the chickens' antibody titer was, the greater the chance of isolating the parasite also was. Sixteen of the 33 isolates (48.5 %) were lethal for all the mice inoculated until 30 days post-inoculation. The risk factors for infection with T. gondii among these free-range chickens were extensive and semi-extensive rearing systems, smallholdings located in urban areas, and presence of cats. The results indicate that the prevalence of T. gondii among chickens in the state of Paraíba is high. Many parasites remained viable in the tissues of the birds studied, and presence of the protozoan was directly related to the management of these birds.

Toxoplasma gondii and Neospora caninum in slaughtered pigs from Northeast, Brazil.

The aims of this study were to evaluate the presence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies, to identify associated risk factors and to isolate T. gondii from slaughtered pigs in Paraíba State, Brazil. A total of 190 pigs from public slaughterhouses were used in the study. An indirect immunofluorescence test was used to detect antibodies, and the isolation of T. gondii was performed with a bioassay in mice based on tissues from seropositive animals. A total of 50 g of brain, heart and tongue tissue from 37 positive pigs with titres ≥ 1:64 was ground, digested with acidic pepsin and inoculated into mice. The prevalence of anti-T. gondii antibodies was 19.5% (95% CI: 14.1%; 25.8%) (37/190), with titres ranging from 1:64 to 1:2048. Viable T. gondii parasites were isolated from 13 of the 37 (35.1%; 95% CI: 20.2%; 52.5%) seropositive pigs. We found that the virulence of the isolates varied; three of these isolates were able to kill all of the inoculated mice. The risk factors for infection were extensive husbandry and feeding with leftovers. The prevalence of antibodies to N. caninum in pigs was 3.2% (95% CI: 1.2%; 6.7%) (6/190), with titres ranging from 1:100 to 1:3200. None of the variables studied were considered to be risk factors for N. caninum. These results show that the prevalence of anti-T. gondii antibodies in swine is high in Paraíba State, that the percentage of viable T. gondii parasites recovered from these animals is also high and that infection by this parasite is closely related to the management of swine. Despite the low prevalence of N. caninum in pigs, further studies are necessary to determine the importance of this parasite for the species.

Prevalence and risk factors associated with goat gastrointestinal helminthiasis in the Sertão region of Paraíba State, Brazil.

Gastrointestinal helminthiasis represents an obstacle to goat raising, causing severe damage to herds such as growth retardation, weight loss, and even death. In this study, we aimed to determine the prevalence and risk factors associated to goat gastrointestinal helminthiasis in the Sertão region of Paraíba State, Brazil. A total of 256 goats from 54 farms were systematically sampled. Blood and fecal samples were collected from each animal for egg per gram (EPG), larval culture, and packed cell volume (PCV) analyses. We found that 79.3% of the goats investigated were parasitized with gastrointestinal helminths. Significant correlation (p = 0.004) was observed between the EPG and PCV of the animals studied, and it was observed that the EPG increases as the PCV decreases. In the larval culture, the most prevalent helminth was Haemonchus sp. (83.2%). Age and sex were significant variables (p ≤ 0.20) for the development of gastrointestinal helminths: 86.8% of animals over 36 months of age and 81.7% of females were infected. The variable type of animal exploitation was also significant, with 90.3% (p ≤ 0.20) of the animals presenting double suitability (milk and meat). The Sertão region of Paraíba State presents high prevalence of gastrointestinal helminthiasis in goats, and age and type of animal exploitation are the most relevant risk factors to the development of these parasites.