Mobility and feeding habits of semi-confined domestic pig groups in a rural locality endemic to cysticercosis

Free-range pigs are in the highest risk to acquire cysticercosis in endemic rural locations, although the behavioral and physiological responses to the infection are known to vary widely between pigs. Those animals reared in semi-confinement showed a group behavior that allows us to follow the herd to assess the risks of contact with the parasite. This study is aimed to determine the movement and feeding habits of pig groups raised under semi-confinement conditions, using minimally invasive procedures, applying trajectory analysis to different herds in rural settings. Pig population and subpopulations were characterized, and their movement was evaluated in two seasons of the year, using a global positioning system (GPS). Our results indicate that pig groups are formed based on human ownership and the establishment of family bonds with each other. Each group interacts with other groups in specific sites of the village. Significant differences were found in the time and distance covered by pigs in the dry and rainy seasons (P < 0.05), and the distance travelled by different groups were found to take place in repetitive, well-defined spaces that include moving through sewage, landfills, and open defecation sites. Due to this stability, the trajectories covered by pigs could be useful as indicators of risk factors linked to the exposure of pigs to Taenia solium

A transdisciplinary approach to disease ecology: Emerging coronaviruses

Humankind is currently facing the effects of an unparalleled pandemic that has impacted healthcare, social, and economic systems worldwide. Numerous studies have been published since the SARS-CoV-2 outbreak began in Wuhan, China. Most have focused on virology, epidemiology, pathogenesis, and therapeutic medicine, having been centered by reactive strategies to control the pandemic. Meanwhile, publications addressing the ecological, evolutionary, and anthropogenic drivers of virus emergence, and potential strategies to prevent future outbreaks have been sparse. Here, we highlight the necessity of complementary and transdisciplinary insight and methodologies from an integrated perspective to study emergent diseases. It is paramount to situate the consistently associated factors to understand the complexity of the current pandemic. Disease ecology can examine information to recognize the causes of emergence while appraising the role of interactions among pathogens, domestic animals, wildlife, and humans, integratively. Here we draw on a variety of disciplines and perspectives, from evolutionary biology, biogeography, ecology, molecular epidemiology and integrative health, to address the emergence of coronaviruses, with particular emphasis on SARS-CoV-2. We describe the process of the surfacing of zoonotic diseases, highlighting the interactions among wildlife, domestic animals, and humans, as well as the genetic, evolutionary, ecological, and anthropogenic processes that favor coronavirus epidemics and epizootics. We discuss specific results related to coronavirus investigations conducted in Mexico based on disease ecology methodologies. Finally, we describe alternative approaches for understanding and preventing future outbreaks and we suggest strategies to entice integrative and transdisciplinary research within the One Health/Ecohealth paradigm.

Efficacy of an extended-release tilmicosin preparation and tulathromycin in the treatment of bovine respiratory disease

A trial to evaluate the treatment of bovine respiratory disease (BRD) was established with tulathromycin (Tul-group) and tilmicosin (Til-group). This latter antibacterial drug is pharmaceutically prepared for 8-10 d sustained release. The challenge was carried out with spontaneously BRD-affected bulls, divided into Til-group (ɳ=44) and Tul-group (ɳ=50). Bulls were treated only once with either antibacterial drugs. Bacteriological analysis, arterial and venous blood chemistry, gasometrical parameters, and body temperature were obtained before and after treatment. The clinical cure rate was registered on days 7, 15, and 30. No mortality was observed. Clinical cure was statistically undistinguishable on these days (P> 0.05), and in both groups, all animals were considered healthy until day 30. Only customary pathogens were isolated i.e., Mannhemia hemolytica 38.88% (70/180), Pasteurella multocida 26.11% (47/180), Histophilus somni 18.33% (33/180, and Trueperella pyogenes 16.66% (30/180).

Attenuation of a Turkeypoxvirus field strain as an alternative to heterologous vaccination in turkeys

Avian pox can severely impact turkey production systems. Vaccination programs in Mexico use commercially available Fowlpoxvirus vaccines, that are used across different bird species. Nonetheless, there are reports of sporadic disease outbreaks among vaccinated turkeys, which suggest that heterologous vaccines may provide limited immunity, presenting the need to develop homologous vaccines that can better protect turkeys. This study compared the protection granted to turkey chicks by a commercial Fowlpoxvirus vaccine and by a live attenuated Turkeypoxvirus vaccine after a challenge with a field isolated Turkeypoxvirus virus. Histopathology, polymerase chain reaction, and sequencing of DNA were used for viral identification. A Turkeypoxvirus strain was first isolated in chicken embryo lesions, and subsequently adapted through serial passes in chorioallantoic membrane to produce the homologous vaccine. The attenuated virus was used as a vaccine when a 104.4 embryo ID50/mL titre was reached. Three groups of three-week-old turkey chicks were used for challenge experiments. Subjects in Group 1 were immunized with the attenuated Turkeypoxvirus vaccine (homologous vaccine). Chicks in Group 2 were vaccinated with the commercially available heterologous vaccine (Fowlpoxvirus). Subjects in Group 3 were not vaccinated and received only saline solution (control group). Two weeks after vaccination, animals from Group 1 reached a 97.7 ND50 seroneutralization titre, while levels reached in Group 2 birds and in control chicks were 11.7 ND50 (Group 2) and zero, respectively. At this time, all groups were challenged with a suspension of a field-isolated Turkeypox virus. The homologous vaccine afforded 100% protection in Group 1 (10/10 individuals), while only 10% (1/10) of individuals in Group 2 were protected by the commercial heterologous Fowlpoxvirus vaccine. None of the non-immunized birds in Group 3 were protected (0/10). These results show that the homologous vaccine afforded a greater protection against a Turkeypox virus infection than that observed for the heterologous vaccine, and that a homologous vaccine can be efficiently produced by isolating and attenuating the virus from turkeypox lesions, through chorioallantoic membrane serial passes.

Pascal Eugène Bergeyre Lagrange. La Aventura Mexicana del Primer Médico Veterinario Civil y Militar de México (1829-1880)

La Aventura Mexicana del Primer Médico Veterinario Civil y Militar de México (1829-1880)

Field immobilization of Desert Bobcats (Lynx rufus) using a Tiletamine-Zolazepam anesthetic combination

Chemical immobilization is used to minimize stress and pain while safely handling wild animals under field conditions. Eight wild bobcats (Lynx rufus) were immobilized for radio collar fittings between March 2005 and March 2007, using a commercial tiletamine hydrochloride-zolazepam hydrochloride combination (Zoletil® Virbac, Carros, France). Bobcats were captured using soft catch spring traps (Victor No. 3) in the Sonoran Desert of Baja California Sur, Mexico. A mean (±SD) intramuscular total dose of 44.3 ± 2.9 mg (6.0 mg kg–1) produced an induction time of 9 ± 4.9 min, and a duration of cataleptic anesthesia of 46.5 ±11.4 min. No adverse reactions were observed in animals during handling, and telemetry monitoring indicated that all individuals were alive for at least one year after the procedure. The results of this study indicate that use of tiletamine-zolazepam administered at 6 mg/kg dose is suitable for short-term chemical immobilization of bobcats in the wild.

Tumor prevalence in cats: experience from a reference diagnostic center in Mexico City (2006-2018)

Records of referred cat cases received for diagnosis in the Department of Pathology of the National Autonomous University of Mexico, School of Veterinary Medicine and Animal Husbandry between 2006 and 2018, were reviewed to examine frequency of occurrence of neoplasms and associated demographic factors. To this end, the records of biopsies, necropsies and clinical information were analyzed to obtain data on animal sex and age, as well as neoplasm histotype, tissue of origin, and malignant/benign biological behavior. A total of 685 neoplasm cases were diagnosed during the study period, which represented 37.7% of all referred histopathological domestic cat cases. Epithelial neoplasms were the most prevalent (56% of cases), followed by mesenchymal tumors (27%), and hematopoietic and lymphoreticular neoplasms (17%). The most common tumor type was carcinoma (31%), followed by sarcoma (14%), adenocarcinoma (13%), lymphoma (13%), and adenoma (6%). Squamous cell carcinoma was the most frequent form of carcinoma (117 cases), followed by lymphoma (88 cases), and spindle cell sarcoma (56 cases). Approximately 85% of all cases corresponded to malignant neoplasms. A relationship between sex and histogenesis was observed, but there was no gender association with malignant behavior. Also, hematopoietic/lymphoreticular tumors occurred more frequently at an early age, than other types of neoplasms. To the extent of our knowledge, this is the first epidemiological report indicating the most common neoplasms in a Mexican domestic cat population.

Epidemia de peste porcina africana: estado actual

La peste porcina africana es una infección viral no zoonótica que se transmite por contacto y por garrapatas. Su notificación debe ser inmediata y es obligatoria. Afecta a cerdos domésticos y silvestres con diversas manifestaciones clínicas. En cerdos domésticos y jabalíes, la presentación clínica es muy similar a la de peste porcina clásica (también conocida como cólera porcino), por lo que es imprescindible una correcta toma de muestras y un rápido envío al laboratorio para lograr un diagnóstico diferencial. Los ciclos de infección se presentan de dos formas: a) selvática, en la que el virus permanece en circulación durante largos períodos entre las garrapatas y los animales persistentemente infectados, y b) epidémica, que involucra a cerdos domésticos y jabalíes, pero raramente se encuentra en los vectores. Los principales signos son fiebre, letargia, y muerte súbita en casos sobreagudos. Si el animal resiste algunos días, se observan diarreas y vómitos con fuertes hemorragias y emaciación de la piel. Los casos más moderados dejan un cierto porcentaje de animales sobrevivientes que permanecen como transmisores de la enfermedad. También pueden existir portadores asintomáticos. No hay tratamiento ni vacunas, por lo que el control de la enfermedad se fundamenta en una detección rápida y en el sacrificio obligatorio de todos los individuos afectados y sospechosos de haber estado en contacto con el virus. La peste porcina africana es endémica en África, Europa del este, China y parte de Asia.

Relaciones antigénicas del virus de la bronquitis infecciosa de las aves con el de la gastroenteritis transmisible de los cerdos

Artículo publicado originalmente en:Romano P. JJ, Velázquez E. A, Olguín R. F. Relaciones antigénicas del virus de la bronquitis infecciosa de las aves con el de la gastroenteritis transmisible de los cerdos. Veterinaria México. 1975;6(2):38–47.- - - La comparación de la cepa FMVZ 69 del virus de la gastroenteritis transmisible de los cerdos, con la cepa Massachusetts del virus de la bronquitis infecciosa de las aves, mediante pruebas de neutralización, fijación de complemento e inmunodifusión reveló que existen relaciones antigénicas entre ambos virus.

Frecuencia de fasciolasis hepática e impacto económico en bovinos sacrificados en Ferrería, Ciudad de México

Artículo originalmente publicado en:Encinas García R, Quiroz Romero H, Guerrero Molina C, Ochoa Galván P. Frecuencia de fasciolasis hepática e impacto económico en bovinos sacrificados en Ferrería, México, D.F. Veterinaria México. 1989;20(4):423–6.- - - A study was conducted in cattle slaughtered at the main abattoir in Mexico City (Ferrería) from January 1977 to December 1988 to determine the monthly and yearly frecuency and economic impact of fasciolasis in the official records of the Sanitary Inspection Service of Ferrería. During this period, 2,101,224 bovines were confiscated, representing 5.19%, equivalent to 763,889 kg of bovine livers with an economic loss of 1275’00,200 pesos. The range of confiscated livers was between 3.70% and 6.28%. The year with the most confiscation was 1977 and the least, 1982; July and March were the months with the highest (6.82%) and the lowest (4.09%) figures, respectively.