Histophilus somni myocarditis and leptomeningitis in feedlot cattle: case report and occurrence in South America

We investigated deaths in a group of feedlot steers in Argentina. The main findings in 3 steers autopsied were pulmonary congestion and edema, necrotizing myocarditis, pericarditis, suppurative leptomeningitis, and bronchopneumonia. Histophilus somni was detected by bacterial culture and immunohistochemistry in the hearts of the 3 animals. Partial sequences of the 16S rRNA gene of a H. somni isolate had 99% similarity with other H. somni sequences in GenBank. Most reports of H. somni septicemia in cattle originate from North America and western Europe. There is scant information about cardiac histophilosis in South America. A survey of diagnostic laboratory personnel in 7 South American countries documented various forms of bovine histophilosis in Argentina, Brazil, Uruguay, and Venezuela.EEA Marcos JuárezFil: Margineda, Carlos Augusto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: O'Toole, Donal. University of Wyoming. Department of Veterinary Sciences. Wyoming State Veterinary Laboratory; Estados UnidosFil: Prieto, Monica. ANLIS “Dr. Carlos Malbran”. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Uzal, Francisco. Universidad de California-Davis. California Animal Health and Food Safety Laboratory; Estados UnidosFil: Zielinski, Gustavo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; Argentin

Estudio de la respuesta inmune frente a la vacunación con virus respiratorio sincitial bovino (VRSB) inactivado en bovinos. Evaluación de la inmunidad pasiva

El objetivo de este trabajo fue evaluar el título y la duración de anticuerpos neutralizantes (AN) en vacas inmunizadas con una vacuna experimental inactivada para el virus respiratorio sincitial bovino (VRSB) y los niveles y la duración de los anticuerpos maternales anti-VRSB transferidos a través del calostrado en los terneros nacidos. Se inoculó un grupo de seis vacas preñadas con una vacuna inactivada de VRSB 90 y 60 días antes del parto. El grupo control estaba formado por seis vacas sin vacunar. Se obtuvieron muestras de suero de las vacas a los días 90, 60, 30 antes del parto y 0, 60 y 120 días posteriores al parto. Con respecto a los terneros, se recolectaron muestras de suero de ambos grupos a las 48 horas posparto y 30, 60, 90 y 120 días luego del nacimiento. La detección de anticuerpos específicos contra el VRSB se realizó mediante seroneutralización viral. En los terneros se determinaron proteínas totales e inmunoglobulina G total a las 48 horas posparto. Solo las vacas vacunadas seroconvirtieron a los 60 días después del refuerzo y los títulos de anticuerpos permanecieron elevados 180 días después de este. Los terneros recién nacidos mostraron una transferencia pasiva efectiva de anticuerpos maternos específicos para el VRSB. En este trabajo fue posible corroborar la inducción y duración de los anticuerpos específicos contra el VRSB en vacas vacunadas con una vacuna inactivada así como en sus respectivos terneros.The aim of this work was to evaluate the titer and duration of neutralizing antibodies in cows immunized with an inactivated experimental vaccine for BRSV and the levels and duration of anti-BRSV maternal antibodies in calves born. A group of six pregnant cows was inoculated with a inactivated BRSV vaccine, at 90 and 60 days before calving. As a control group, six animals were mock inoculated. Cows´ serum samples were obtained at days 90, 60, 30 before calving and at 0, 60 and 120 days postpartum. Sera from calves were obtained at 48-72 hours postpartum, 30, 60, 90 and 120 days after birth. The kinetic of serum specific antibodies from inoculated animals and newborn calves was analyzed by a serum neutralization assay. Only the vaccinated cows serocoverted 60 days post booster and antibody titers remained high 180 days post booster. Six newborn calves showed an effective passive transfer of specific BRSV maternal antibodies. In this work, it was possible to determine antibody levels against BRSV and their duration after vaccination of cows and calves born using an inactivated vaccine.Fil: Margineda, Carlos Augusto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Ferella, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Pérez Aguirreburualde, María Sol. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Samarruco, A.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Gonzalez, Diego Daniel. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Toledo, G.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Dus Santos, María José. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Mozgovoj, Marina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentin

Atypical actinobacillosis in bulls in Argentina: granulomatous dermatitis and lymphadenitis

Actinobacillosis is a common cause of sporadic infection in cattle. It was mostly characterized as a pyogranulomatous inflammation of the tongue, but also soft tissues as lymph nodes, other digestive tract localization and skin. The aim of this study was to describe an episode of granulomatous dermatitis and lymphadenitis affecting a bull herd in Argentina during 2010. Actinobacillus lignieresii was isolated from samples collected from one of the affected bulls, and characteristic lesions were observed. Lesions other than 'wooden tongue' are usually uncommon; however, actinobacillosis should be included as a differential diagnosis for cutaneous diseases

Atypical actinobacillosis in bulls in Argentina: granulomatous dermatitis and lymphadenitis

Actinobacillosis is a common cause of sporadic infection in cattle. It was mostly characterized as a pyogranulomatous inflammation of the tongue, but also soft tissues as lymph nodes, other digestive tract localization and skin. The aim of this study was to describe an episode of granulomatous dermatitis and lymphadenitis affecting a bull herd in Argentina during 2010. Actinobacillus lignieresii was isolated from samples collected from one of the affected bulls, and characteristic lesions were observed. Lesions other than 'wooden tongue' are usually uncommon; however, actinobacillosis should be included as a differential diagnosis for cutaneous diseases

Atypical actinobacillosis in bulls in Argentina: granulomatous dermatitis and lymphadenitis

Actinobacillosis is a common cause of sporadic infection in cattle. It was mostly characterized as a pyogranulomatous inflammation of the tongue, but also soft tissues as lymph nodes, other digestive tract localization and skin. The aim of this study was to describe an episode of granulomatous dermatitis and lymphadenitis affecting a bull herd in Argentina during 2010. Actinobacillus lignieresii was isolated from samples collected from one of the affected bulls, and characteristic lesions were observed. Lesions other than 'wooden tongue' are usually uncommon; however, actinobacillosis should be included as a differential diagnosis for cutaneous diseases

<i>Mycoplasma bovis</i> pneumonia in feedlot cattle and dairy calves in Argentina

Mycoplasma bovis has emerged as an important cause of feedlot pneumonia in many countries. The aim of this paper is to describe six cases of bovine Mycoplasma pneumonia in five different premises in Argentina. Gross examination revealed chronic bronchopneumonia with multiple foci of caseous necrosis. Microscopically, these contained a necrotic center with abundant hypereosinophilic granular material surrounded by granulation tissue. Affected lung tested positive for M. bovis by immunohistochemistry and electron microscopy revealed membranous structures compatible with Mycoplasma spp. To our knowledge, this is the first report of M. bovis pneumonia in Argentina.Facultad de Ciencias Veterinaria

<i>Mycoplasma bovis</i> pneumonia in feedlot cattle and dairy calves in Argentina

Mycoplasma bovis has emerged as an important cause of feedlot pneumonia in many countries. The aim of this paper is to describe six cases of bovine Mycoplasma pneumonia in five different premises in Argentina. Gross examination revealed chronic bronchopneumonia with multiple foci of caseous necrosis. Microscopically, these contained a necrotic center with abundant hypereosinophilic granular material surrounded by granulation tissue. Affected lung tested positive for M. bovis by immunohistochemistry and electron microscopy revealed membranous structures compatible with Mycoplasma spp. To our knowledge, this is the first report of M. bovis pneumonia in Argentina.Facultad de Ciencias Veterinaria