Serological Survey of Toxoplasma gondii Infection in the Domestic Goose (Anser domestica) in Southern China

Epidemiologic significance of Toxoplasma gondii infections in turkeys, ducks, ratites and other wild birds: 2009-2020

Toxoplasma gondii infections are common in humans and animals worldwide. Wild and domestic avian species are important in the epidemiology of T. gondii infections because felids prey on them and excrete millions of oocysts in the environment, disseminating the infection. Herbivorous birds are also excellent sentinels of environmental contamination with T. gondii oocysts because they feed on the ground. Toxoplasma gondii infections in birds of prey reflect infections in intermediate hosts. Humans can become infected by consuming undercooked avian tissues. Here, the authors reviewed prevalence, persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from turkeys, geese, ducks, ratites and avian species (excluding chickens) worldwide 2009-2020. Genetic diversity of 102 T. gondii DNA samples isolated worldwide is discussed. The role of migratory birds in dissemination of T. gondii infection is discussed.

Serological evidence of exposure to Toxoplasma gondii and Neospora caninum in free-ranging Orinoco goose (Neochen jubata) in Brazil

Toxoplasma gondii and Neospora caninum are Apicomplexan intracellular protozoan parasites that affect numerous animal species, thus leading to severe diseases and economic losses, depending on the vertebrate species involved. The role of the avian species in maintaining and transmission of these coccidia has been studied for several years as they tend to serve as a potential source of infection for mammals and humans. The present study aimed to assess the serological exposure of Orinoco goose (Neochen jubata) to T. gondii and N. caninum. Between 2010 and 2013, 41 free-ranging Orinoco geese were captured in the Araguaia River, Brazil. The presence and titration of IgY antibodies to both coccidia were assayed via indirect immunofluorescent antibody test (IFAT). While IgY antibodies for N. caninum were present in 5 animals, with titers of 20, the antibodies for T. gondii were found in 35 animals, with titers ranging from 20 to 640. Considering that the Orinoco goose's meat is consumed by the local population in the studied area, it may represent an important source of T. gondii infection for humans. Due to its migratory behavior, this goose may play a pivotal role in the natural dispersion of both parasites. Furthermore, molecular studies are required for genotyping the isolates of T. gondii that occurs in this avian species.

Serosurvey of Toxoplasma gondii, Sarcocystis sp. and Neospora caninum in geese (Anser sp.) from urban parks and captivity

Geese, ducks, mallards, and swans are birds of the order Anseriformes, which are found in the wild, in zoos and parks, and raised for meat consumption. Toxoplasma gondii, Sarcocystis sp., and Neospora caninum are protozoans of several species of animals. Wild and domestic birds can serve as intermediate hosts, disseminators and potential sources of infection of these protozoa to humans through contaminated meat. The aims of this study were: (i) to perform a serological survey of T. gondii, Sarcocystis sp. and N. caninum in geese (Anser sp.) from public parks and from captivity and (ii) to compare seroprevalence between these two locations. Antibodies were detected by Immunofluorescence antibody test using the serum of 149 geese. Antibodies to Sarcocystis sp., T. gondii, and N. caninum were detected in 28.18%, 18% and 0.67% of geese, respectively; 57% of geese from urban parks and 26.53% of geese from captivity were seropositive for at least one protozoa. The results indicate environmental contamination, particularly for the occurrence of antibodies against T. gondii - a zoonosis that causes toxoplasmosis and is transmitted through oocyte ingestion. This is the first serological survey of T. gondii, Sarcocystis sp. and N. caninum in geese from urban parks in Curitiba, Brazil.

Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta canadensis)

Wild birds are important in the epidemiology of toxoplasmosis because they can serve as reservoir hosts, and vectors of zoonotic pathogens including Toxoplasma gondii. Canada goose (Branta canadensis) is the most widespread geese in North America. Little is known concerning T. gondii infection in both migratory, and local resident populations of Canada geese. Here, we evaluated the seroprevalence, isolation, and genetic characterization of viable T. gondii isolates from a migratory population of Canada geese. Antibodies against T. gondii were detected in 12 of 169 Canada geese using the modified agglutination test (MAT, cutoff 1:25). The hearts of 12 seropositive geese were bioassayed in mice for isolation of T. gondii. Viable parasites were isolated from eight. One isolate was obtained from a seropositive goose by both bioassays in mice, and in a cat; the cat fed infected heart excreted T. gondii oocysts. Additionally, one isolate was obtained from a pool of four seronegative (<1:25) geese by bioassay in a cat. The T. gondii isolates were further propagated in cell culture, and DNA extracted from cell culture-derived tachyzoites were characterized using 10 polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genetic markers (SAG1, 5' and 3'SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The results revealed five different genotypes. ToxoDB PCR-RFLP genotype #1 (type II) in one isolate, genotype #2 (type III) in four isolates, genotype #4 in two isolates, and two new genotypes (ToxoDB PCR-RFLP genotype #266 in one isolate and #267 in one isolate) were identified. These results indicate genetic diversity of T. gondii strains in the Canada geese, and this migratory bird might provide a mechanism of T. gondii transmission at great distances from where an infection was acquired.

Seroprevalence, risk factors and genotyping of Toxoplasma gondii in domestic geese (Anser domestica) in tropical China

BACKGROUND

Little information is available about the seroprevalence of Toxoplasma gondii infection in geese (Anser domestica) in China. In the present investigation, the seroprevalence, risk factors and genotyping of T. gondii in geese were investigated in Hainan province, tropical China.

FINDINGS

A total of 600 serum samples and 150 brain tissue samples were collected from six administrative regions in tropical China, and assayed for T. gondii antibodies by Indirect Haemagglutination (IHA) test. Genomic DNA was extracted from the 30 brain tissues of seropositive geese and T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genetically characterized using multi-locus PCR-RFLP. Overall, 17% (95% CI: 14-20) of the animals were positive for T. gondii antibodies. Presence of cats in the household (odds ratio, OR 3), hygiene (OR 2.3) and presence of stray cat around the house (OR 2.3) were considered as main risk factors associated with T. gondii infection. Of 30 DNA samples, three were positive for the T. gondii B1 gene, two showed complete genotyping results. Only one genotype (type II) was identified.

CONCLUSIONS

The results of the present survey indicated the presence of T. gondii infection in geese in tropical China. Therefore, it is imperative that improved integrated measures be carried out to prevent and control T. gondii infection in geese in this province. This is the first report documenting the occurrence of T. gondii genotype in geese in China.

Seroprevalence of Toxoplasma gondii infection in slaughtered chickens, ducks, and geese in Shenyang, northeastern China

Background

In recent years, investigations of Toxoplasma gondii infection in poultry (chickens, ducks, and geese) have been reported worldwide, including China. However, little is known about the prevalence of T. gondii infection in poultry in northeastern China. Therefore, the present study was performed to determine the prevalence of T. gondii infection in slaughtered chickens, ducks, and geese in Shenyang, northeastern China.

Methods

In the present study, the seroprevalence of T. gondii in 502 adult chickens, 268 adult ducks, and 128 adult geese was surveyed using the modified agglutination test (MAT).

Results

The seroprevalences of T. gondii were 5.8%, 7.8%, and 4.7% in chickens, ducks, and geese, respectively. Prevalence was higher in free-range groups (11.2%, 12.3%, and 8.9%) than caged groups (4.7%, 7.5%, and 6.0%), and there was a statistically significant difference only between free-range chickens and caged chickens, but no significant difference was found between free-range ducks, geese and caged ducks, geese.

Conclusions

The present study shows the prescence of T. gondii infection in slaughtered chickens, ducks, and geese in Shenyang, northeastern China, which suggests that consumption of poultry meat in Shenyang may pose a potential threat to human health and should be given attention.

First report of Toxoplasma gondii infection in market-sold adult chickens, ducks and pigeons in northwest China

BACKGROUND

Toxoplasma gondii infection is a global concern, affecting a wide range of warm-blooded animals and humans worldwide, including poultry. Domestic and companion birds are considered to play an important role in the transmission of T. gondii to humans and other animals. However, little information on T. gondii infection in domestic birds in Lanzhou, northwest China was available. Therefore, this study was performed to determine the seroprevalence of T. gondii infection in domestic birds in Lanzhou, northwest China.

METHODS

In the present study, the seroprevalence of T. gondii antibodies in 413 (305 caged and 108 free-range) adult chickens, 334 (111 caged and 223 free-range) adult ducks and 312 adult pigeons in Lanzhou, northwest China, were examined using the modified agglutination test (MAT).

RESULTS

30 (7.26%) chickens, 38 (11.38%) ducks and 37 (11.86%) pigeons were found to be positive for T. gondii antibodies at the cut-off of 1:5. The prevalences in caged and free-range chickens were 6.23% and 10.19% respectively, however, statistical analysis showed that the difference was not significant (P > 0.05). The seroprevalences in caged and free-range ducks were 6.31% and 13.90% respectively, but the difference was not statistically significant (P > 0.05).

CONCLUSIONS

The results of the present survey indicated the presence of T. gondii infection in adult chickens, ducks and pigeons sold for meat in poultry markets in Lanzhou, northwest China, which poses a potential risk for T. gondii infection in humans and other animals in this region. This is the first seroprevalence study of T. gondii infection in domestic birds in this region.