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BACKGROUND AND AIM: Brachyspira are Gram-negative, aerotolerant spirochetes that colonize the large intestine of various species of domestic animals and humans. The aim of this study was to determine the presence and distribution of different species of Brachyspira presents in feces from finishing pigs in Argentina. MATERIALS AND METHODS: Fecal samples (n=1550) were collected from finishing pigs in 53 farms of the most important swine production areas of Argentina, and Brachyspiras species were identified by bacteriological and molecular methods. RESULTS: The regional prevalence of Brachyspira spp. was at the level of 75.5% (confidence interval 95%, 62.9-87.9), and it was lower among those farms with >1001 sows. One hundred and twenty-eight isolates of Brachyspira were properly identified and the species found were: Brachyspira hyodysenteriae, Brachyspira pilosicoli, Brachyspira innocens, and Brachyspira murdochii. B. hyodysenteriae and B. pilosicoli had low prevalence (1.9% and 7.5%, respectively), B. innocens was isolated from 34% of the farms and B. murdochii was found in 39.6%. CONCLUSION: The present study provides epidemiological data about herd prevalence of the different Brachyspira species in Argentina, showing that the prevalence figure seems to be higher than that reported in other countries.
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Two cross-sectional studies were carried out in 2013 and 2015 monitoring for Mycoplasma hyopneumoniae presence in a swine farm. In these studies, the genetic diversity of M. hyopneumoniae was assessed in clinical specimens using a Multiple Locus Variable-number tandem repeat Analysis (MLVA) targeting P97 R1, P146 R3 and H4 loci. The samples from August 2015 showed the MLVA profile prevalent in June 2013, therefore it can be concluded that a same genetic type of M. hyopneumoniae can persist for at least two years in a closed herd. In addition, the nested PCR reactions implemented in this study showed to be useful for MLVA typing in non-invasive clinical samples.
Asunto(s)
Mycoplasma hyopneumoniae , Neumonía Porcina por Mycoplasma , Animales , Estudios Transversales , Variación Genética , Repeticiones de Minisatélite , Mycoplasma hyopneumoniae/genética , Mycoplasma hyopneumoniae/aislamiento & purificación , Neumonía Porcina por Mycoplasma/genética , PorcinosRESUMEN
Several species of Mycoplasma and Ureaplasma diversum can cause diseases in dairy cattle, which can be associated or not with clinical manifestations. In our country, the presence of Mycoplasma bovis, Mycoplasma californicum and Mycoplasma canadense has been detected, being the only mycoplasma species identified so far. The objective of this study was to identify other species of the Mycoplasmataceae family. Thirty-five Mycoplasma spp.-like isolates obtained from different samples from cattle, with or without clinical symptoms, from eight herds located in the provinces of Santa Fe, Cordoba, Buenos Aires and San Luis were utilized in the present study. Through the use of species-specific polymerase chain reactions (PCR) Mycoplasma bovigenitalium, Mycoplasma alkalescens, Mycoplasma bovirhinis and U. diversum were identified and through amplification and further sequencing of the 16-23S rRNA intergenic spacer regions, Mycoplasma arginine and M. californicum were identified. The identification of these species represents an important advance in knowledge in order to include these pathogens in the differential diagnosis of certain clinical and pathological entities of cattle from Argentina.
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Enfermedades de los Bovinos , Mycoplasma , Ureaplasma , Animales , Argentina , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Mycoplasma/genética , Mycoplasma/aislamiento & purificación , Infecciones por Mycoplasma/veterinaria , Reacción en Cadena de la Polimerasa , Ureaplasma/genética , Ureaplasma/aislamiento & purificación , Infecciones por Ureaplasma/veterinariaRESUMEN
ABSTRACT: To assess the success of a segregated medicated early weaning protocol for elimination of Actinobacillus pleuropneumoniae, ten consecutive batches of 100 pigs per batch weaned at 7-9 days of age were monitored at 21-22 weeks of age looking for presence of productive cough, presence of antibodies against the agent and pleuropneumonia-compatible lung lesions at slaughter. Also, whole tonsils were processed for A. pleuropneumoniae identification by both bacteriological isolation and nested-PCR using a direct method. Positive serological test (1.4%) and PCR (3.5%) results, suggested that A. pleuropneumoniae could not be eradicated in all batches, even using segregated medicated early weaning protocol.
RESUMO: Para avaliar o sucesso de um protocolo de desmame precoce segregado medicado para a eliminação de Actinobacillus pleuropneumoniae, dez lotes consecutivos de 100 suínos por lote desmamados aos 7-9 dias de idade foram monitorados às 21-22 semanas de idade procurando a presença de tosse produtiva, presença de anticorpos contra o agente e lesões pulmonares compatíveis com pleuropneumonia no abate. Além disso, as tonsilas inteiras foram processadas para a identificação de A. pleuropneumoniae por isolamento bacteriológico e nested PCR usando um método direto. Os resultados serológicos (1,4%) e PCR (3,5%) positivos sugerem que não foi possível erradicar em todos os lotes, mesmo usando um protocolo de desmame precoce segregado medicado.
RESUMEN
O objetivo deste estudo foi monitorar a presença de M. hyopneumoniae em granjas suínas durante a implementação de programas de erradicação utilizando diferentes técnicas de diagnóstico focalizando no PCR. Trabalhou-se com uma empresa que possuía três granjas, uma parto-terminação (390 matrizes), uma múltiplo-sítio (4100 matrizes) e uma nova granja que povoava suas novas instalações. Nas duas primeiras, foi desenvolvido um programa de despovoamento parcial para erradicar a pneumonia enzoótica suína, a última foi povoada pelos suínos dos anteriores após a erradicação. Nos três rebanhos, os suínos foram monitorados por: sorologia (ELISA), PCR, lesões pulmonares macro e microscópicas e a presença de tosse não produtiva. A ausência de tosse, a baixa porcentagem de suínos soropositivos na fase de terminação e a baixa proporção de lesões pulmonares no abate sugerem que a pneumonia enzoótica suína foi erradicada, mas não o agente causativo -M. hyopneumoniae- cujo DNA foi detectado pela PCR, mostrando diferentes comportamentos de acordo com o rebanho.
The aim of this study was to monitor the presence of M. hyopneumoniae in pig farms during the implementation of eradication programs using different diagnostic techniques focusing on PCR. They worked with a company owner of three farms, a farrow-to-finish (390 sows), a multiple-site (4100 sows) and a new one that was populated its new facility. In the first two were developed a partial depopulation program to eradicate swine enzootic pneumonia, the latter one was populated with pigs after the previous eradication. In the three farms, the pigs were monitored by: serology (ELISA), PCR, macroscopic and microscopic lung lesions and the presence of non-productive cough. The absence of cough, low percentage of seropositive pigs in the finishing stage and the low proportion of lung lesions at slaughter suggest that swine enzootic pneumonia was eradicated, but not the causative agent -M. hyopneumoniae- whose DNA was detected by PCR showing different behaviors according to the herd.
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La vacunación con la cepa China es utilizada para prevenir la Peste Porcina Clásica. Pero la presencia de anticuerpos pasivos y la edad de los lechones a la vacunación pueden originar una respuesta humoral activa no satisfactoria. Se vacunaron animales de 7, 21 y 56 días de edad con y sin inmunidad pasiva. Se tomaron muestra de sangre al momento de la vacunación y a los 15 y 45 días posteriores. Los animales respondieron de distintas maneras a la vacunación, según la presencia o no de anticuerpos pasivos. Se observó que a mayor edad de vacunación, mayor era el porcentaje de animales que respondieron a la vacuna en el último muestreo. La técnica de ELISA no permitió detectar anticuerpos a los 15 días de vacunados.
The vaccination with the Chinese strain is used to prevent the Classical Swine Fever. But the presence of passive antibodies and age of piglets at the time of vaccination can originate an unsatisfactory active humoral response. In this study 7, 21 and 56 days animals with and without passive immunity, were vaccinated. Blood samples were taken at the time of vaccination and then at 15 and 45 days later. The animals responded in different ways to vaccination, according to the presence or not of passive antibodies. It was observed that as greater the age of vaccination, greater was the percentage of animals that responded to the vaccine in the last sampling. The ELISA technique did not allow detecting antibodies 15 days after vaccination.
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Animales , Afinidad de Anticuerpos , Peste Porcina Clásica , Vacunación/veterinariaRESUMEN
En un estudio de pseudocohortes se inspeccionaron los miembros craneales y caudales de 3142 lechones lactantes de 5 a 27 días de vida, para evaluar prevalencia de lesiones y su evolución, clasificándolas por edad y región anatómica. El trabajo se desarrolló en un establecimiento porcino de crianza intensiva, de ciclo completo, todo adentro-todo afuera, con 1200 madres totales y un promedio de 50 partos semanales, con una edad de destete promedio de 24 días. De los 3142 lechones, 249 (7.92%) no presentaron lesiones, en los restantes 2893 (92.8%) se observaron 8415 lesiones, correspondiendo 3869 (46%) a fibrosis, 4314 (51.20%) a heridas y 232 (2.8%) a artritis. De ese total 5165 (61.4%) correspondieron a los carpos, 737 (8.8%) a los tarsos y 2513 (29.9%) a las pezuñas. En lechones de 5-9 días de edad las heridas representaron el 73.8% del total de lesiones, las que tuvieron dos formas de evolución, hacia la fibrosis o la artritis. Esta evolución de las heridas mayormente tiende a la fibrosis en el carpo y a la artritis en el tarso. Se concluye que los miembros de lechones en maternidad presentan alta prevalencia de lesiones bilaterales desde la edad temprana y principalmente en los miembros craneales.
The purpose of this work was to study the prevalence, evolution and type of lesions occurring in the front and back legs of 3142 suckling piglets from 5 to 27 days of age, also classifying ithem according to age and anatomical region. From the total 3142 piglets, 249 (7.92%) did not have any visible lesions. In the other 2893 (92.08%) piglets, a total of 8415 different lesions were observed. Over this total, an amount of 3869 (46%) piglets showed fibrosis, 4314 (51.20%) had different type of injuries and 232(2.8%) presented arthritis. Over the total of 8415 lesions, 5165 (61.4%), 737 (80.8%), and 2513 (29.9%) had lesions on the carpus, tarsus and hoofs, respectively. Injuries represented 73.8% of the total lesions in 5 to 9 days old piglets, which evolved either towards fibrosis or arthritis. Fibrosis was the product of evolution on lesions mainly in the carpus, whereas arthritis evolved mainly in the tarsus.
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Se realizó un estudio clínico-patológico en cerdos criados al aire libre, estos presentaron signos de desmejoramiento y muerte entre los 40 a 90 días de vida. Durante un periodo determinado se registraronlos índices de mortalidad en las categorías de recría y levante. A un grupo de animales con signos de desmejoramiento se les extrajo sangre y se les realizó la necropsia. Se tomaron muestras de tejidos para la realización de análisis histopatológicos, inmunohistoquímicos, bacteriológicos, parasicológicos y virológicos. Los índices de mortalidad estuvieron incrementados en la primera parte del período estudiado. Los signos clínicos observados fueron: retardo en el crecimiento, pérdida de peso y muerte. A la necropsia se observó palidez de mucosas, ganglios linfáticos megálicos y friables, edema de pericardio y de cavidad abdominal. En pulmón se observó neumonía intersticial. El riñón se mostró con áreas blanquecinas en corteza y edema en pelvis. Las lesiones observadas microscópicamente fueron: depleción linfocitaria en órganos linfoides, infiltración de histiocitos, presencia de células gigantes, cuerpos de inclusión intra citoplasmáticos y necrosis multifocales. Además, tanto las células gigantes, los cuerpos de inclusión y los macrófagos de las áreas foliculares de los tejidos linfoides, se manifestaron como inmunorreactivos en la técnica del complejo abidina biotina (ABC) frente al anticuerpo monoclonal del circovirus porcino tipo II (CVP2). Estos hallazgos confirman la presencia de Síndrome de Multisistémico de Desmejoramiento Posdestete (SMDP) en cerdos criados al aire librecon cuadros clínicos patológicos similares a los descriptos en sistemas confinados.