Factors associated with endoparasites and ectoparasites in domiciled dogs in the metropolitan area of Toluca, México / Factores asociados con la presencia de endoparásitos y ectoparásitos en perros domiciliados de la zona metropolitana de Toluca, México.

Introduction: Endoparasites and ectoparasites in dogs are of global distribution. The close relationship between dogs and man implies a risk for the transmission of zoonotic parasites. Therefore, it is necessary to determine the parasites hosted by dogs in specific areas and the factors associated with their presence. Objectives: To identify and to estimate the prevalence of endoparasites and ectoparasites in domiciled dogs in the Metropolitan area of Toluca, México, and the prevalence of D. caninum in fleas of the genus Ctenocephalides spp. Materials and methods: We collected samples from 402 domiciled dogs in four reference hospitals in the area in Toluca. We diagnosed endoparasites using direct smear, flotation, and sedimentation techniques and we performed the taxonomic identification of ectoparasites. Finally, the molecular diagnosis of D. caninum in fleas was made using the polymerase chain reaction technique (PCR). Results: A total of 37.2% of dogs were positive for endoparasites; the genera or species identified were Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp., and Trichuris vulpis; the prevalence of ectoparasites was 13.13%. We identified fleas of the species Ctenocephalides felis, Ctenocephalides canis; only one animal was parasitized with Rhipicephalus sanguineus and another one with Trichodectes canis; the prevalence of D. caninum in fleas was 9.5%. Conclusion: The prevalence of endoparasites was 37.2% while that of ectoparasites was 13.1%; this is the first analysis of endoparasites and ectoparasites conducted in the same population of dogs in México together with the molecular diagnosis of D. caninum in fleas.

Introducción. Los endoparásitos y ectoparásitos en perros son de distribución mundial. La estrecha relación entre los perros y el hombre implica un riesgo de transmisión de parasitosis zoonóticas, por lo cual es necesario conocer las especies que parasitan a los perros de esta zona y determinar los factores asociados. Objetivos. Estimar la prevalencia de endoparásitos y ectoparásitos, identificarlos en perros domiciliados de la zona metropolitana de Toluca, México, y determinar la prevalencia de Dipyilidium caninum en pulgas del género Ctenocephalides spp. Materiales y métodos. Se recolectaron muestras de 402 perros que fueron llevados a consulta en cuatro hospitales de referencia de Toluca. En el diagnóstico de endoparásitos, se utilizaron las técnicas coproparasitoscópicas de frotis directo, flotación y sedimentación; además, se recolectaron ectoparásitos para su identificación taxonómica. Por último, la detección de D. caninum en pulgas se hizo mediante la reacción en cadena de la polimerasa (PCR). Resultados. El 37,2 % de los perros resultó positivo para endoparásitos. Los géneros o especies identificados fueron Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp. y Trichuris vulpis. Se determinó una prevalencia de ectoparásitos de 13,13 %. Se identificaron pulgas de las especies Ctenocephalides felis y C. canis, en tanto que solo un animal presentó parasitosis por Rhipicephalus sanguineus y otro por Trichodectes canis. La prevalencia de D. caninum en pulgas fue del 9,5 %. Conclusión. La prevalencia de endoparásitos fue de 37,2 % y, la de ectoparásitos, de 13,1 %. Por primera vez en México se hizo un análisis de endoparásitos y ectoparásitos en una misma población de perros, así como el diagnóstico molecular de D. caninum.

Factores asociados con la presencia de endoparásitos y ectoparásitos en perros domiciliados de la zona metropolitana de Toluca, México / Factors associated with endoparasites and ectoparasites in domiciled dogs in the metropolitan area of Toluca, México

Resumen | Introducción. Los endoparásitos y ectoparásitos en perros son de distribución mundial. La estrecha relación entre los perros y el hombre implica un riesgo de transmisión de parasitosis zoonóticas, por lo cual es necesario conocer las especies que parasitan a los perros de esta zona y determinar los factores asociados. Objetivos. Estimar la prevalencia de endoparásitos y ectoparásitos, identificarlos en perros domiciliados de la zona metropolitana de Toluca, México, y determinar la prevalencia de Dipyilidium caninum en pulgas del género Ctenocephalides spp. Materiales y métodos. Se recolectaron muestras de 402 perros que fueron llevados a consulta en cuatro hospitales de referencia de Toluca. En el diagnóstico de endoparásitos, se utilizaron las técnicas coproparasitoscópicas de frotis directo, flotación y sedimentación; además, se recolectaron ectoparásitos para su identificación taxonómica. Por último, la detección de D. caninum en pulgas se hizo mediante la reacción en cadena de la polimerasa (PCR). Resultados. El 37,2 % de los perros resultó positivo para endoparásitos. Los géneros o especies identificados fueron Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp. y Trichuris vulpis. Se determinó una prevalencia de ectoparásitos de 13,13 %. Se identificaron pulgas de las especies Ctenocephalides felis y C. canis, en tanto que solo un animal presentó parasitosis por Rhipicephalus sanguineus y otro por Trichodectes canis. La prevalencia de D. caninum en pulgas fue del 9,5 %. Conclusión. La prevalencia de endoparásitos fue de 37,2 % y, la de ectoparásitos, de 13,1 %. Por primera vez en México se hizo un análisis de endoparásitos y ectoparásitos en una misma población de perros, así como el diagnóstico molecular de D. caninum.

Abstract | Introduction: Endoparasites and ectoparasites in dogs are of global distribution. The close relationship between dogs and man implies a risk for the transmission of zoonotic parasites. Therefore, it is necessary to determine the parasites hosted by dogs in specific areas and the factors associated with their presence. Objectives: To identify and to estimate the prevalence of endoparasites and ectoparasites in domiciled dogs in the Metropolitan area of Toluca, México, and the prevalence of D. caninum in fleas of the genus Ctenocephalides spp. Materials and methods: We collected samples from 402 domiciled dogs in four reference hospitals in the area in Toluca. We diagnosed endoparasites using direct smear, flotation, and sedimentation techniques and we performed the taxonomic identification of ectoparasites. Finally, the molecular diagnosis of D. caninum in fleas was made using the polymerase chain reaction technique (PCR). Results: A total of 37.2% of dogs were positive for endoparasites; the genera or species identified were Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp., and Trichuris vulpis; the prevalence of ectoparasites was 13.13%. We identified fleas of the species Ctenocephalides felis, Ctenocephalides canis; only one animal was parasitized with Rhipicephalus sanguineus and another one with Trichodectes canis; the prevalence of D. caninum in fleas was 9.5%. Conclusion: The prevalence of endoparasites was 37.2% while that of ectoparasites was 13.1%; this is the first analysis of endoparasites and ectoparasites conducted in the same population of dogs in México together with the molecular diagnosis of D. caninum in fleas.

Epidemiology of feline urolithiasis in Mexico (2006-2017).

OBJECTIVES: The objectives of this study were to identify the proportions of different types of uroliths, characterize the population of cats that present with urolithiasis and determine possible predisposing factors in a population of Mexican cats. METHODS: This study analyzed clinical specimens of feline urolithiasis submitted to our laboratory in the period from 2006 to 2017. The mineral composition of the uroliths was determined by qualitative and quantitative mineral analyses, performed by stereoscopic microscopy and infrared spectroscopy. RESULTS: In the population studied, 54.3% of all uroliths were calcium oxalate, followed by 32.1% struvite and 7.4% purine (urate and xanthine) uroliths, with other types accounting for 6.2% of submissions. The male:female ratio was 1.2:1. Calcium oxalate submissions were predominantly from males and struvite submissions were predominantly from females. The age of the cats with stone submissions ranged from 6 months to 17 years. In cats with calcium oxalate uroliths, 52.3% were aged 7 years or older. Cats with struvite uroliths were younger, with 65.4% younger than 6 years of age. Almost 90% of all submitted uroliths were from domestic shorthair cats. CONCLUSIONS AND RELEVANCE: This is the first epidemiologic study of urolithiasis in cats in Mexico. Age and sex predispositions to common uroliths were identified, as males aged ≥7 years primarily presented with calcium oxalate uroliths and females aged <6 years primarily presented struvite uroliths. Cases of urolithiasis of genetic origin, including xanthinuria and cystinuria, were also detected, in addition to silicate uroliths.

A quantitative framework to evaluate modeling of cortical development by neural stem cells.

Neural stem cells have been adopted to model a wide range of neuropsychiatric conditions in vitro. However, how well such models correspond to in vivo brain has not been evaluated in an unbiased, comprehensive manner. We used transcriptomic analyses to compare in vitro systems to developing human fetal brain and observed strong conservation of in vivo gene expression and network architecture in differentiating primary human neural progenitor cells (phNPCs). Conserved modules are enriched in genes associated with ASD, supporting the utility of phNPCs for studying neuropsychiatric disease. We also developed and validated a machine learning approach called CoNTExT that identifies the developmental maturity and regional identity of in vitro models. We observed strong differences between in vitro models, including hiPSC-derived neural progenitors from multiple laboratories. This work provides a systems biology framework for evaluating in vitro systems and supports their value in studying the molecular mechanisms of human neurodevelopmental disease.

Preventive and therapeutic DNA vaccination partially protect dogs against an infectious challenge with Trypanosoma cruzi.

American trypanosomiasis, or Chagas disease, is caused by Trypanosoma cruzi, and a vaccine would greatly improve disease control. While some studies in mice suggest that a vaccine is feasible, limited efficacy has been observed in dogs. We evaluated here the safety and efficacy of a DNA vaccine encoding TSA-1 and Tc24 antigens in a dog model of acute T. cruzi infection. Mongrel dogs were immunized with two doses of 500 µg of DNA vaccine, two weeks apart, and infected with T. cruzi (SylvioX10/4 strain) two weeks after the second vaccine dose. Another group of dogs was infected first and treated with the vaccine. Disease progression was monitored for up to 70 days post-infection. The vaccine did not induce any critical change in blood parameters, nor exacerbation of disease in vaccinated animals. On the contrary, it prevented anemia and a decrease in lymphocyte counts following T. cruzi infection in vaccinated dogs. Both preventive and therapeutic vaccination significantly reduced parasitemia, cardiac inflammation and cardiac parasite burden, and tended to reduce the development of cardiac arrhythmias. These results indicate that a preventive or therapeutic DNA vaccine encoding TSA-1 and Tc24 antigens is safe and may reduce both parasite transmission and the clinical progression of Chagas disease in vaccinated dogs. This DNA vaccine may thus be an excellent veterinary vaccine candidate. These data also further strengthen the feasibility of a Chagas disease vaccine for humans.

Seroprevalence survey of American trypanosomiasis in Central Valley of Toluca.

American trypanosomiasis is a growing health issue in the Americas. México is an endemic country, where some locations such as in the State of México are considered highly prevalent. In the valley of Toluca city, the capital of the State of Mexico, there exists an apparent high prevalence in dogs. The absence of triatomine vectors suggests that dogs may not be infected. Therefore, we conducted a directed survey to domiciliated and nondomiciliated dogs to reassess dogs' T. cruzi seroprevalence status. HAI and ELISA serologic tests were applied to 124 and 167 serums of domiciliated and nondomiciliated dogs in the target city. Risk factors were estimated, but the results did not show any evidence to assess them. No domiciliated dogs tested positive to both tests, whereas only one non-domiciliated dog resulted positive. This animal may have acquired the infection in an endemic area and then migrated to Toluca. Research results indicate that T. cruzi infection is not actively transmitted among dogs, and it is pointed out that dogs are the main sentinel animal population to evaluate a possible expansion of the territory affected by Chagas' disease.

Evaluation of clinical and immunopathological features of different infective doses of Trypanosoma cruzi in dogs during the acute phase.

Infection with Trypanosoma cruzi is a major risk in Latin America, and dogs are believed to be good models for evaluating Chagas disease. Here, we evaluated the clinical and immunopathological alterations developed by mongrel dogs experimentally infected with different infective doses (2,000, 20,000, and 200,000 metacyclic trypomastigotes of Sylvio X10/4 strain kg(-1) via intraperitoneal). Clinical and electrocardiographic parameters, as well as antibody production and pathologic lesions were evaluated. All three doses of this strain of T. cruzi induced a similar pattern of infection characterized by cardiac arrhythmias and severe and diffuse myocarditis. Specific anti-T. cruzi IgG indicated seroconversion by day 14 after infection, and IgG levels increased during the period of evaluation. Mortality was observed only in dogs infected with the medium or high parasite doses, but not in the group infected with a low dose of 2,000 parasites kg(-1). Infection with a low dose of parasites provides an excellent nonlethal model to evaluate the immunopathology of the acute disease in dogs infected with the Sylvio X10/4 strain of T. cruzi.