Evaluación de la seroconversión de cerdas con el uso de un inóculo a diferentes dosis y vehículos contra la diarrea epidémica porcina

Porcine epidemic diarrhea (PED) is a highly contagious enteric disease of pigs, which has caused great economic losses to the swine industry worldwide. The known measure for PED control prior to the development and launch of vaccines in 2017 in Mexico, was "feedback" or "liquefaction". It was a widely used measure during the PED outbreak in 2013; however, there is no homogeneity in its use among the various authors who recommend it. Currently, several studies have experimented with other types of prophylaxis, such as oral immunization with PED virus obtained from cell culture isolation, which allows quantification of the infectious virus and ensures that only the virus, and no other agent, is being used as inoculum. The objective of the present study was to compare the time of seroconversion in sows inoculated with the quantified virus with four different vehicles (milk, wheat, direct, and water) and different doses of vehicle (1 ml, 2 ml, and 3 ml) at different pregnancy stages and with a different number of farrowings. The study was conducted at CEIEPP, a full-cycle farm with 170 females. The present study showed that the vehicles with the best results were the inoculum with water and the direct inoculum combined with the 1 ml dose, as the combination of these vehicles and an inoculum dose resulted in seroconversion in more than 90 % of the sows from the second week post inoculation.La diarrea epidémica porcina (PED) es una enfermedad entérica altamente contagiosa en los cerdos, que ha provocado grandes pérdidas económicas a la industria porcina a nivel mundial. Las medidas conocidas para el control de la PED, antes del desarrollo y lanzamiento de las vacunas en el 2017 en México, fue el “feedback” o “licuado”. Aunque fue una medida muy utilizada durante el brote de PED en 2013, entre los diversos autores que lo recomiendan no hay una homogeneidad en su uso. Actualmente, diversos estudios han experimentado otro tipo de profilaxis, como la inmunización oral con el virus de la PED obtenido a partir del aislamiento en cultivo celular, lo que permite cuantificar el virus infectivo, así como asegurar que solo se está utilizando como inóculo al virus y no otros agentes. El objetivo del presente estudio fue comparar el tiempo de seroconversión, en cerdas inoculadas con virus cuantificado, con cuatro diferentes vehículos (leche, trigo, directo y agua) y diferentes dosis del vehículo (1 ml, 2 ml y 3 ml), en diferentes momentos de gestación y número de partos. El estudio se realizó en el CEIEPP, granja de ciclo completo con 170 hembras. El presente estudio demostró que los vehículos con mejores resultados fueron el inóculo con agua y el inóculo directo combinado con la dosis de 1 ml, ya que la combinación de estos vehículos y dosis del inóculo generó que más del 90 % de las cerdas mostraran seroconversión a partir de la segunda semana post-inoculación

Molecular Detection and Characterization of Porcine Epidemic Diarrhea Virus and Porcine Aichivirus C Coinfection in México

Swine enteric viral infections are responsible for substantial economic losses in the pork industry worldwide. Porcine epidemic diarrhea (PEDV) is one of the main causative agents of diarrhea in lactating pigs, and reports of PEDV coinfection with other enteric viruses highlight the importance of viral interactions for disease presentation and outcomes. Using next-generation sequencing (NGS) and sequence analyses from samples taken from piglets with acute diarrhea, we explored the possible interactions between PEDV and other less reported pathogens. PEDV coinfection with porcine kobuvirus (PKV) was detected in 36.4% (27/74) of samples. Full genomes from porcine coronavirus and kobuvirus were obtained, as was a partial porcine sapovirus genome (PSaV). The phylogenetic results show the clustering of these strains corresponding to the geographical relationship. To our knowledge, this is the first full genome and isolation report for porcine kobuvirus in México, as well as the first phylogenetic analysis for porcine sapovirus in the country. The NGS approach provides a better perspective of circulating viruses and other pathogens in affected production units