Assessment of antibodies against three zoonotic bacteria and associated risk factors in pig farms in Colombia. / Evaluación de anticuerpos frente a tres bacterias zoonóticas y factores de riesgo asociados en explotaciones porcinas de Colombia.

The aim of this study was to determine the seroprevalence of Salmonella spp., Mycobacterium bovis and Brucella spp., together with associated risk factors, in pigs from various farms in seven regions of Colombia. A total of 350 blood samples were obtained from pigs at different stages in the production cycle of 23 farms, which were tested using the enzyme-linked immunosorbent assay (ELISA) diagnostic kits Pigtype®-Salmonella Ab (Qiagen®, Hilden, Germany), INgezim TB porcine and INgezim Brucella porcine (Ingenasa®, Madrid, Spain). The overall seroprevalence for Salmonella spp. was 42.85% (n = 150) and, for M. bovis, it was 5.42% (n = 19). No positive samples were detected for Brucella spp. In the farms evaluated, the presence of pests, such as rodents, was found to be the management variable with a statistically significant association with seropositivity for Salmonella spp. and M. bovis. The results suggest that, at some point in the primary production cycle, pigs came into contact with zoonotic bacteria, resulting in seropositivity, which may pose a risk to public health and national pig production.

Les auteurs présentent les résultats d'une étude menée en Colombie pour déterminer la prévalence sérologique de Salmonella spp., de Mycobacterium bovis et de Brucella spp. et d'identifier les facteurs de risques associés chez les porcs de différents élevages répartis dans sept régions du pays. Au total, 350 prélèvements sanguins de porcs en différentes phases du cycle de production et provenant de 23 exploitations ont été analysés en utilisant les kits de diagnostic suivants : test immuno-enzymatique (ELISA) Pigtype®-Salmonella Ab (Qiagen®, Hilden, Allemagne), INgezim TB porcina et INgezim Brucella porcina (Ingenasa®, Madrid, Espagne). La prévalence sérologique globale de Salmonella spp. était de 42,85 % (n = 150) et celle de M. bovis de 5,42 % (n = 19) ; aucun échantillon n'a été trouvé positif pour Brucella spp. En ce qui concerne les facteurs en lien avec la gestion des élevages, une corrélation significative au plan statistique a été observée dans les exploitations étudiées entre la présence de ravageurs (rongeurs notamment) et l'apparition d'anticorps dirigés contre Salmonella spp. et M. bovis. Les résultats obtenus laissent penser que les porcs ont été exposés à ces bactéries zoonotiques à un moment ou un autre du cycle de production primaire, ce qui a déclenché l'apparition d'anticorps ; il s'agit d'une situation à risque tant pour la santé publique que pour la filière porcine du pays.

El objetivo del presente estudio fue determinar la seroprevalencia respectoa Salmonella spp., Mycobacterium bovis y Brucella spp., junto con los factores de riesgo asociados, en porcinos de diferentes explotaciones de producción en siete regiones de Colombia. Se obtuvieron 350 muestras sanguíneas de porcinos de diferentes etapas del ciclo productivo provenientes de 23 explotaciones,y estas fueron analizadas utilizando los estuches de ensayo inmunoenzimático (ELISA) para diagnóstico Pigtype®-Salmonella Ab (Qiagen®, Hilden, Alemania), INgezim TB porcina e INgezim Brucella porcina (Ingenasa®, Madrid, España). La seroprevalencia general respecto a Salmonella spp. fue del 42,85% (n = 150),y para M. bovis, del 5,42% (n = 19); no se detectó ninguna muestra positiva respecto a Brucella spp. Se determinó que en las explotaciones evaluadas, la presencia de plagas, como los roedores, fue la variable de manejo con asociación estadísticamente significativa a la seropositividad respecto a Salmonella spp.y a M. bovis. Los resultados obtenidos sugieren que, en algún momento del ciclo de producción primaria, los cerdos estuvieron en contacto con las bacterias zoonóticas frente a las que se obtuvo seropositividad, lo cual puede representar un riesgo para la salud pública y la producción porcina a nivel nacional.

Exposure assessment of Salmonella spp. in fresh pork meat from two abattoirs in Colombia.

Salmonella spp. prevails as the main cause of raw meat foodborne illnesses. Implementation of food safety management systems such as Hazard Analysis and Critical Control Points in swine abattoirs can help to mitigate pathogen exposure. The objective of the present study was to evaluate the impact of the HACCP system in slaughterhouses in Colombia on reducing Salmonella spp. exposure due to the consumption of fresh pork meat. Two slaughtering plants with a different degree of HACCP implementation were selected and a quantitative microbiological mapping was built by collecting 820 samples of Salmonella spp. enumeration at different processing stages. The overall Salmonella spp. mean concentration was 1.15 ± 0.55 log MPN/g, with no significant differences among plants (P > 0.05). Deficiencies during carcass disinfection and temperature during distribution of meat cuts from the slaughterhouse lacking of HACCP resulted in a significant increase of Salmonella spp. prevalence (20-40%) (P < 0.05). Processing stages with the highest pathogen prevalence were transport (28-32%) and hanging (16-36%). The exposure assessment model estimated a higher degree of pathogen contamination at the time of consumption in meat cuts from the slaughterhouse without HACCP (3.36 versus 3.68 log MPN/g) and 10-fold increase in the probability a consumer would acquire a contaminated portion (0.011 versus 0.105). Implementation of the HACCP system in swine slaughterhouses represents tangible Salmonella spp. reduction control and public health protection measures.