Occurrence and genetic characterization of Toxoplasma gondii and Neospora caninum in slaughtered domestic rabbits in central China

Global prevalence of lagomorpha coccidiosis from 1951 to 2024: A systematic review and meta-analysis

The global prevalence of coccidia infection in lagomorphs and potential risk factors were investigated through a meta-analysis of 149 studies published between 1951 and 2024. The pooled prevalence of Eimeriidae, Sarcocystidae and Cryptosporidiidae was found to be 66.0 %, 8.0 % and 6.1 %, respectively. Rabbits and hares exhibited the highest prevalence of Eimeriidae at 63.1 % and 71.8 %, while pikas had the highest prevalence of Cryptosporidiidae at 17.1 %. Countries located in the southern hemisphere exhibited the highest prevalence of Cryptosporidiidae (11.4 %). The African Region had the highest prevalence of Eimeriidae (73.3 %) and Sarcocystidae(14.6 %), while the Eastern Mediterranean Region had the highest prevalence of Cryptosporidiidae(13.6 %). Juvenile rabbits exhibited the highest prevalence of Eimeriidae (67.4 %), while senior Rabbit exhibited the highest prevalence of Sarcocystidae(17.1 %) and Cryptosporidiidae(13.1 %). The prevalence of coccidia in intensively farmed lagomorphs showed a slight upward trend over time, nearly reaching statistical significance (R2 = 7.88 %, coefficient = 0.019, P = 0.127). This suggests that the current intensive farming practices may be losing effectiveness in controlling coccidia infections, which is concerning. Among Eimeriidae in lagomorphs, Eimeria coquelinae showed the highest prevalence (68.4 %), while E. magna was most frequently reported. For Sarcocystidae, Besnoitia spp. had the highest prevalence (31.3 %), with Toxoplasma gondii being most frequently reported. Cryptosporidium cuniculus was both the most prevalent and frequently reported Cryptosporidiidae species (6.9 %), suggesting it may be a major Cryptosporidiidae pathogen in lagomorphs. These findings highlight the differences in prevalence of various Eimeriida species among different lagomorpha genera. This diversity underscores the complex relationships between specific parasites and their host species, contributing to a more nuanced understanding of coccidiosis epidemiology in lagomorphs worldwide.

Involvement of extracellular vesicles in the interaction of hosts and Toxoplasma gondii

Toxoplasma gondii, the causative agent of toxoplasmosis, is widely distributed. This protozoan parasite is one of the best adapted, being able to infect innumerous species of animals and different types of cells. This chapter reviews current literature on extracellular vesicles secreted by T. gondii and by its hosts. The topics describe the life cycle and transmission (1); toxoplasmosis epidemiology (2); laboratorial diagnosis approach (3); The T. gondii interaction with extracellular vesicles and miRNAs (4); and the perspectives on T. gondii infection. Each topic emphases the host immune responses to the parasite antigens and the interaction with the extracellular vesicles and miRNAs.

Toxoplasma gondii in Foods: Prevalence, Control, and Safety

Toxoplasma gondii is an obligate intracellular parasite that causes toxoplasmosis, with approximately one third of the population around the world seropositive. The consumption of contaminated food is the main source of infection. These include meat products with T. gondii tissue cysts, and dairy products with tachyzoites. Recently, contamination has been detected in fresh products with oocysts and marine products. Despite the great health problems that are caused by T. gondii, currently there are no standardized methods for its detection in the food industry. In this review, we analyze the current detection methods, the prevalence of T. gondii in different food products, and the control measures. The main detection methods are bioassays, cell culture, molecular and microscopic techniques, and serological methods, but some of these do not have applicability in the food industry. As a result, emerging techniques are being developed that are aimed at the detection of multiple parasites simultaneously that would make their application more efficient in the industry. Since the prevalence of this parasite is high in many products (meat and milk, marine products, and vegetables), it is necessary to standardize detection methods, as well as implement control measures.

Epidemiological and Public Health Significance of Toxoplasma gondii Infection in Wild Rabbits and Hares: 2010-2020

Toxoplasmosis is a zoonosis of global distribution, and Toxoplasma gondii infections are common in humans and animals worldwide. Hares and rabbits are important small game species, and their meat is consumed by humans in many countries. Demand for rabbit meat for human consumption is increasing; therefore, toxoplasmosis in rabbits and hares is of epidemiological significance. Viable T. gondii has been isolated from rabbits. The present review summarizes worldwide information on the seroprevalence, parasitological investigations, clinical cases, isolation, and genetic diversity of T. gondii in wild rabbits, free domestic rabbits, hares, and other rabbits from 2010 to 2020. Differences in prevalence, susceptibility, genetic variants, and clinical implications of T. gondii infection in rabbits and hares are discussed. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers. Additional studies are needed to increase our knowledge of genetic variants and the population structure of T. gondii in rabbits and hares and to understand the differences in susceptibility to T. gondii in hares in different areas.

Molecular Detection and Genotyping of Toxoplasma gondii and Neospora caninum in Slaughtered Goats in Central China

Toxoplasma gondii and Neospora caninum infections can cause reproductive failure in animals, including goats, and toxoplasmosis is one of the most important foodborne diseases. However, information on the molecular prevalence and genetic characterization of T. gondii and N. caninum in the tissues of goats in China is limited. In this study, brain samples of 422 slaughtered goats were collected from slaughterhouses in Henan and Anhui provinces, Central China, and examined for the presence of T. gondii and N. caninum by nested polymerase chain reaction (PCR) based on B1 and NC5 genes, respectively. The prevalence of T. gondii and N. caninum DNA was 5.2% and 2.8%, respectively. No significant differences were found between the prevalences of two parasite infections and animal age, sex, and region (p > 0.05). Two of 22 T. gondii-positive samples were completely genotyped at 11 genetic markers (SAG1, [3' + 5'] SAG2, alternative SAG2 [alt. SAG2], SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) using PCR-restriction fragment length polymorphism, and were identified as genotype ToxoDB no. 225, which has not been previously reported in goats in any country worldwide. For N. caninum, two different sequences at the ITS1 region, three genotypes at the MS5 microsatellite locus, and one genotype at the MS8 locus were identified. This study showed that T. gondii and N. caninum are moderately prevalent in goats in Central China; however, it should be emphasized that T. gondii prevalence in goats poses a potential health threat for consumers in the investigated areas. To the best of our knowledge, this is the first report on the genetic characterization of N. caninum isolates from goats in China. Our results have important implications for a better understanding of the genetic diversity of these parasites in China.