ABSTRACT A clinical case of tuberculous meningoencephalitis in a 5-month-old Holstein calf that presented nervous symptoms is described. The calf was part of a herd with a 30% prevalence of tuberculosis. The animal was euthanized, and a necropsy was performed. No lesions were found in organs of the thoracic or abdominal cavity. Brain samples were taken for histopathology (hematoxylin-eosin and Zielh Nelsen staining), bacteriology and PCR-MRD1 studies. In the brain, macroscopic inflammatory lesions with congestion and granular appearance were observed in the meninges, as well as fibrous adhesions in the ventral area. Microscopically, inflammatory infiltrate, lymphocytes, macrophages, epithelioid cells, plasma cells and multinucleated giant cells, areas of central necrosis, dystrophic mineralization and acid-fast bacilli were observed. Granulomatous meningoencephalitis due to Mycobacterium bovis was confirmed by bacterial isolation and PCR-MRD1.

RESUMEN Se describe un caso clínico de meningoencefalitis tuberculosa en un ternero Holstein de cinco meses de edad que presentaba signología nerviosa; además de pertenecer a un hato con 30% de prevalencia a tuberculosis. Se llevó a cabo la eutanasia del animal y se practicó la necropsia. No se encontraron lesiones en órganos de cavidad torácica ni abdominal. Se tomaron muestras de encéfalo para estudios de histopatología (tinción con hematoxilina-eosina y Zielh Nelsen), bacteriología y PCR-MRD1. En el encéfalo se observaron lesiones inflamatorias macroscópicas con congestión y aspecto granular en meninges, así como adherencias fibrosas en la zona ventral. Microscópicamente se observó infiltrado inflamatorio, linfocitos, macrófagos, células epitelioides, células plasmáticas y células gigantes multinucleadas, áreas de necrosis central, mineralización distrófica y bacilos ácido-alcohol resistentes. La meningoencefalitis granulomatosa por Mycobacterium bovis se confirmó por aislamiento bacteriano y PCR-MRD1.

Abstract The review focused on concisely presenting the contributions that INIFAP researchers have developed, directly or in collaboration with researchers from other institutions, on different aspects of the diseases that affect cattle farming in Mexico. It describes the research on viral diseases such as rabies and bovine viral diarrhea; bacterial diseases such as anaplasmosis, brucellosis, tuberculosis, paratuberculosis, leptospirosis and bovine respiratory disease, and among parasitic diseases, tick infestation and babesiosis. It identifies potential lines of research that can help mitigate the impact of diseases on production. It considers contributions on the development or adaptation of serological and molecular diagnostic techniques and the diagnosis of resistance to ixodicides. In addition, it indicates epidemiological parameters of the diseases and makes reference to the biologics generated, which include vaccines against rabies, anaplasmosis and babesiosis; bacterin against leptospirosis, and a bacterin-toxoid against pneumonia. It also discusses the evaluations of the use of BCG against tuberculosis and a new generation vaccine against brucellosis. The review concludes that the research of INIFAP in animal health must necessarily have the omic sciences as a perspective. This is the only way to complement the understanding of disease mechanisms, the development of new diagnostic techniques and the design of effective and safe vaccines. Therefore, the great challenge will be the involvement of the animal health area in the concept of "One Health".

Resumen La revisión se enfocó en presentar de manera concisa las aportaciones que investigadores del INIFAP, han desarrollado directamente o en colaboración con investigadores de otras instituciones sobre diferentes aspectos de las enfermedades que afectan a la ganadería bovina en México. Se describen investigaciones sobre enfermedades virales como la rabia y la diarrea viral bovina; bacterianas como la anaplasmosis, brucelosis, tuberculosis, paratuberculosis, leptospirosis y enfermedad respiratoria bovina; de las enfermedades parasitarias se incluye a la infestación por garrapatas y a la babesiosis. Se identifican posibles líneas de investigación que pueden coadyuvar a mitigar el impacto de las enfermedades en la producción. Se señalan aportes sobre el desarrollo o adaptación de técnicas diagnósticas de tipo serológico y molecular y se considera el diagnóstico de resistencia a los ixodicidas. Además, se indican parámetros epidemiológicos de las enfermedades y se refieren los biológicos generados que comprenden vacuna contra rabia, anaplasmosis y babesiosis; bacterina contra leptospirosis y una bacterina-toxoide contra neumonías. Asimismo, se comentan las evaluaciones del uso de BCG contra tuberculosis y una vacuna de nueva generación contra la brucelosis. En la revisión se concluye que la investigación del INIFAP en salud animal debe forzosamente tener como perspectiva las ciencias ómicas. Solo así se complementará el entendimiento de los mecanismos de las enfermedades, el desarrollo de nuevas técnicas diagnósticas y el diseño de vacunas efectivas y seguras. De modo que el gran reto será el involucramiento del área de salud animal al concepto de "Una Salud".

Abstract Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis (PTB), disease that causes a syndrome of bad nutrient absorption, weight loss and eventually death. The intestine is the main target organ where the infection develops; however, there is evidence of infection by MAP in extra-intestine sites of sheep, including mesenteric nodes and semen. The aim of the study was to identify the presence of MAP in reproductive tissue and semen of infected Pelibuey rams in clinical state of PTB. Seven rams were used in clinical PTB state and a non-infected ram by MAP of the Pelibuey breed, confirmed by serology, nPCR and bacteriological culture, with average weight and age of 57.23 ± 1.73 kg and 2.91 ± 0.17 years, respectively. The presence of MAP was identified in different tissue samples: spleen (1/7, 14.3% and 2/7, 28.6%), small intestine (3/7, 42.9% and 4/7, 57.1%) and mesenteric lymph nodes (3/7, 42.9% and 3/7, 42.9%), with nPCR and culture, respectively. It was also identified in epididymis tissue (1/7, 14.3%), Cowper gland (2/7, 28.6%) and prostate (1/7, 14.3%), using nPCR, although without detection in culture. It was identified in testicular tissue in 42.8% (3/7; culture or nPCR technique), but in 28.6% (2/7) with both techniques. Finally, the presence of MAP was identified in 42.9% (3/7) of semen samples with nPCR; however, it was not detected through culture. In conclusion, the presence of MAP was identified in lymphatic, digestive tissue, and semen; the presence of MAP was reported for the first time in epididymis, Cowper gland, prostate and testicles of infected Pelibuey rams.

The objective of this study was to standardize and develop an ELISA with protoplasmatic antigen from a Mycobacterium avium paratuberculosis (Map) 3065 strain obtained from sheep, to be used for the diagnosis of bovine paratuberculosis. The antigen was set on plates at 10, 5, 2.5 and 1.25 μg/100 μl concentrations and 1:20, 1:40, 1:80 and 1:160 dilutions of positive and negative control sera were tested. The cutoff point was established with a confidence interval of 95% and two standard deviations. Four-hundred and ninety-one bovine sera were used to establish sensitivity and specificity of the ELISA; likewise feces samples were collected for bacteriological isolation and the nested polymerase chain reaction test (PCR) was applied for Map detection. Results of the three tests were analyzed by kappa test to determine association or concordance. Antigen and sera concentration that gave the best difference between controls was 1.25 μg/100 μl antigen and 1:160 serum dilution, cutoff point was established at an optic density of 0.196; obtained sensitivity was 79.31 %, while specificity was 82.25 % and concordance index of the ELISA was 0.2763 as compared to the culture. Results obtained by ELISA with protoplasmatic antigen of the Map 3065 strain make the recommendation of this assay appropriate as an alternative for the diagnosis of bovine paratuberculosis.

Los objetivos del trabajo fueron estandarizar y desarrollar un ELISA con antígeno protoplasmático obtenido de una cepa de Mycobacterium avium paratuberculosis (Map) 3065 de origen ovino, para el diagnóstico de paratuberculosis en bovinos. El antígeno se fijó en las placas a concentraciones de 10, 5, 2.5 y 1.25 μg/100 μl y se probaron diluciones de los sueros control positivo y negativo de 1:20, 1:40, 1:80 y 1:160. El punto de corte se estableció con un intervalo de confianza del 95 % y dos desviaciones estándar. Para determinar la sensibilidad y especificidad del ELISA se trabajó con 491 sueros de bovinos, así como también, se colectaron muestras de heces para efectuar el aislamiento bacteriológico, y la prueba de reacción en cadena de la polimerasa (PCR) anidada para la detección de Map. Los resultados de las tres pruebas fueron analizadas para determinar la asociación o concordancia por medio de una prueba de Kappa La concentración de antígeno y suero que dieron mejor diferencia entre los controles fue de 1.25 μg/100 μl antígeno y la dilución del suero 1:160, el punto de corte se estableció a una densidad óptica de 0.196; la sensibilidad que se obtuvo fue 79.31 %, la especificidad 82.25 % y el índice de concordancia de 0.2763 del ELISA con respecto al cultivo. Los resultados obtenidos permiten recomendar el ELISA con antígeno protoplasmático de la cepa de Map 3065, como una alternativa para el diagnóstico de la paratuberculosis en bovinos.

Paratuberculosis is a chronic granulomatous enteritis caused by Mycobacterium avium subspecies paratuberculosis (Map), which affects wild and domestic ruminants. Map is shed in feces from infected animals. Transmission of the infection takes place by oral ingestion of the bacterium from contaminated food and water with feces. With the objective to establish a paratuberculosis diagnosis in ovine by nested-PCR from fecal samples, 204 fecal and serum ovine samples were studied. Feces were evaluated by nested-PCR and bacterial culture, serum samples were analyzed by agar gel immunodiffusion (AGID). Nested-PCR yielded a 210 bp amplification product that corresponds to Map-IS900, in 61 out of 204 samples. From these, 43 were from AGID positive animals and 18 from negative animals. Seventeen Map strains were isolated by bacterial culture and AGID detected 91 positive animals. Nested-PCR allowed to detect, sooner, greater number of animals shedding bacillus, even when they had resulted negative to the serological test. This result is considered important because generally these animals, while remaining in the farm, constitute the main source of infection for the herd. Nested-PCR should be considered as an alternative, when a prompt result is required to know the health status of the herd with respect to paratuberculosis.

La paratuberculosis es una enteritis granulomatosa de curso crónico ocasionada por Mycobacterium avium subespecie paratuberculosis (Map), afecta a rumiantes domésticos y silvestres. Map es excretada en las heces de animales que desarrollan la enfermedad, y la transmisión de la infección se da mediante la ingestión de alimentos y agua contaminados por heces de animales infectados. Con el objetivo de establecer el diagnóstico de paratuberculosis en ovinos por medio de la PCR-anidada a partir de muestras de heces, se trabajaron 204 muestras de heces y sueros de ovinos; las heces se evaluaron por PCR-anidada y cultivo bacteriológico, las muestras de sueros fueron analizadas por medio de inmunodifusión en agar gel (lDGA). Con la PCR-anidada se obtuvo un producto de amplificación 210 pb que corresponde a la IS900 de Map, en 61 de las 204 muestras. De éstas, 43 eran de animales positivos a IDGA y 18 negativos. Mediante cultivo bacteriológico se aislaron 17 cepas de Map; en este contexto, la IDGA detectó a 91 animales como positivos. La PCR-anidada permitió detectar en menor tiempo a mayor cantidad de animales que estaban eliminando al bacilo, aun cuando habían resultado negativos a la prueba serológica; este resultado se considera importante, ya que generalmente estos animales, al permanecer dentro de la granja, constituyen la principal fuente de infección para el rebaño. Se debe considerar a la PCR-anidada como alternativa, cuando se requiera el diagnóstico en breve tiempo, para conocer el estado sanitario del rebaño con respecto a paratuberculosis.