In vitro amplification of BVDV field strains isolated in Argentina: effect of cell line and culture conditions

The aim of this work was to study the in vitro amplification of BVDV (Pestivirus, Flaviridae) field isolates from Argentina in MDBK, BoTur and BHK-21 continuous cell lines. Field isolates 99/134 (mucosal disease), 00/693 (mucosal disease), 04P7016 (respiratory disease) and 04/89 (mucosal disease), genotype 1b, were used and compared with the Singer and NADL reference strains, genotype 1a. Additionally, cell lines derived from explants of bovine testis (RD-420), bovine uterus (NCL-1) and porcine kidney (PKZ) were tested as alternative substrates for BVDV propagation in vitro. The effect of cell line, harvest time and infection protocol was evaluated. The viral titers observed depended on the virus and harvest time but not on the infection protocol. We found that MDBK and BoTur cell lines were susceptible to the infection whereas BHK-21 and PKZ were not. NADL viral titers, 00/693 and 04/89, increased from 24 to 48 h p.i. in BoTur cells and then reached a plateau, whereas those of 99/134 and 04P7016 remained constant between 24 and 72 h p.i. BVDV Singer, on the other hand, presented a maximum titer at 24 h p.i. and then decreased. BVDV-NADL titers increased in MDBK and NCL-1 but not in RD-420 between 24 and 48 h p.i., and then decreased at 72 h p.i. These facts lead us to conclude that neither the subgenotypes (1a, 1b) nor the clinical symptoms of the animal from the virus had been isolated seem to affect the virus cell line kinetics of viral replication in vitro. On the other hand, the most homogenous behavior, the most similar replication curves, and highest titers observed in MDBK and NCL-1 seem to indicate that these lines are generally more susceptible to BVDV replication.The aim of this work was to study the in vitro amplification of BVDV (Pestivirus, Flaviridae) field isolates from Argentina in MDBK, BoTur and BHK-21 continuous cell lines. Field isolates 99/134 (mucosal disease), 00/693 (mucosal disease), 04P7016 (respiratory disease) and 04/89 (mucosal disease), genotype 1b, were used and compared with the Singer and NADL reference strains, genotype 1a. Additionally, cell lines derived from explants of bovine testis (RD420), bovine uterus (NCL-1) and porcine kidney (PKZ) were tested as alternative substrates for BVDV propagation in vitro. The effect of cell line, harvest time and infection protocol was evaluated. The viral titers observed depended on the virus and harvest time but not on the infection protocol. We found that MDBK and BoTur cell lines were susceptible to the infection whereas BHK-21 and PKZ were not. NADL viral titers, 00/693 and 04/89, increased from 24 to 48 h p.i. in BoTur cells and then reached a plateau, whereas those of 99/134 and 04P7016 remained constant between 24 and 72 h p.i. BVDV Singer, on the other hand, presented a maximum titer at 24 h p.i. and then decreased. BVDV-NADL titers increased in MDBK and NCL-1 but not in RD-420 between 24 and 48 h p.i., and then decreased at 72 h p.i. These facts lead us to conclude that neither the subgenotypes (1a, 1b) nor the clinical symptoms of the animal from the virus had been isolated seem to affect the virus cell line kinetics of viral replication in vitro. On the other hand, the most homogenous behavior, the most similar replication curves, and highest titers observed in MDBK and NCL-1 seem to indicate that these lines are generally more susceptible to BVDV replication.Fil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Leunda, Maria Rosa. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Faverin, Claudia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Boynak, Natalia. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Vena, M. M.. Biogénesis-Bagó S. A.; ArgentinaFil: Zabal, O.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentin

Role of assisted reproduction biotechniques in the transmission of bovine viral diarrhea virus

Las biotécnicas de reproducción asistida han adquirido importancia comercial en los últimos años. Asociado a estas técnicas surge el interrogante sobre su rol en la posible transmisión de agentes infecciosos vía semen y ovocitos utilizados como material de partida. La elevada prevalencia y capacidad de causar infecciones reproductivas del virus de la Diarrea Viral Bovina (vDVB) lo ha convertido en un problema potencial en la producción in vitro de embriones. La presente revisión aborda los antecedentes previos sobre la temática y muestra resultados propios sobre las vías de infección del virus de la Diarrea Viral Bovina (vDVB) asociadas a las técnicas de producción in vitro (PIV) y su impacto en la reproducción bovina. Los resultados obtenidos demuestran alteraciones en el desarrollo folicular ovárico asociadas a infecciones persistentes por vDVB. Estas alteraciones fueron reflejadas en la baja eficiencia obtenida en la fecundación in vitro (FIV) como resultado de la interacción temprana entre el virus y la línea germinal del ovario. Por otra parte, se determinó que el vDVB-no citopático (vDVB-ncp) puede atravesar la zona pelúcida de ovocitos bovinos infectados al inicio de la etapa de maduración in vitro (MIV). Este hallazgo pone en evidencia la importancia de controles sanitarios en los sistemas de producción in vitro basados en la comprensión de los riesgos de transmisión del virus a partir de semen y ovocitos. Asimismo, la asociación del vDVB con gametas fue demostrada cuando la FIV se realizó tanto con ovocitos como con semen de animales persistentemente infectados (PI), donde se observó una disminución en las tasas de división y desarrollo de embriones. La información presentada en este artículo de revisión aporta al conocimiento sobre las implicancias de infecciones por vDVB en los sistemas de PIV y su efecto en el desarrollo embrionario, como así también al impacto de la transmisión de la infección en el ganado bovino mediante técnicas de reproducción asistida.Biotechnical of assisted reproduction have become commercially important in recent years. Associated with these techniques the question about his possible role in the transmission of infectious agents via semen and oocytes used as starting material arises. The high prevalence and ability to cause reproductive infections of the bovine viral diarrhea virus (BVDV) has become a potential problem in the in vitro production embryos. This update addresses the previous data on the subject and shows own results on the ways of infection with bovine viral diarrhea (BVDV) associated with in vitro production techniques and their impact on the reproduction bovine. The results demonstrate changes in the ovarian follicular development associated with persistent BVDV infection. These changes were reflected in the low efficiency obtained in the in vitro fertilization as a result of early interaction between the virus and ovarian germ line. Moreover, it was determined that non-cytopathic BVDV can cross the zona pellucida of bovine oocytes infected at the beginning of the stage of in vitro maturation. This finding highlights the importance of to understand fully the risks of transmission of virus via semen and oocytes and appropriate quality assurances are used in in vitro production embryos systems (IVP). Likewise, the association of BVDV was demonstrated with gametes when IVF was performed with both types from animals infected persistent, where a decrease was observed in cleavage rates and embryo development. The information obtained in this review article contributes to knowledge about the implications of BVDV infections in IVP systems and its effect on embryonic development, as well as the impact of the transmission of infection in cattle by breeding techniques assisted.Fil: Gonzalez Altamiranda, Erika Analia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Kaiser, Germán Gustavo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Laboratorio de Biotecnología de la Reproduccion; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentin

Phylogenetic analyses of typical bovine rotavirus genotypes G6, G10, P[5] and P[11] circulating in Argentinean beef and dairy herds

Group A rotavirus (RVA) is one of the main causes of neonatal calf diarrhea worldwide. RVA strains affecting Argentinean cattle mainly possess combinations of the G6, G10, P[5] and P[11] genotypes. To determine RVA diversity among Argentinean cattle, representative bovine RVA strains detected in diarrheic calves were selected from a survey conducted during 1997–2009. The survey covered the main livestock regions of the country from dairy and beef herds. Different phylogenetic approaches were used to investigate the genetic evolution of RVA strains belonging to the prevalent genotypes. The nucleotide phylogenetic tree showed that all genotypes studied could be divided into several lineages. Argentinean bovine RVA strains were distributed across multiple lineages and most of them were distinct from the lineage containing the vaccine strains. Only the aminoacid phylogenetic tree of G6 RVA strains maintained the same lineages as observed at the nucleotide level, whereas a different clustering pattern was observed for the aminoacid phylogenetic trees of G10, P[5] and P[11] suggesting that the strains are more closely related at the aminoacid level than G6 strains. Association between P[5] and G6(IV), prevalent in beef herd, and between P[11] and G6(III) or G10 (VI and V), prevalent in dairy herds, were found. In addition, Argentinean G6(III), G10, P[5] and P[11] bovine RVA strains grouped together with human strains, highlighting their potential for zoonotic transmission. Phylogenetic studies of RVA circulating in animals raised for consumption and in close contact with humans, such as cattle, contribute to a better understanding of the epidemiology of the RVA infection and evolution.Fil: Badaracco, Alejandra. 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: Garaicoechea, Lorena Laura. 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: Matthijnssens, J.. University of Leuven. Rega Institute for Medical Research; BélgicaFil: Louge Uriarte, Enrique Leopoldo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Bilbao, Gladys Noemí. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Fernandez, Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Parra, G. I.. National Institutes of Health; Estados UnidosFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Estrés en ganado: causas y consecuencias

En los últimos años se está dando una importancia creciente a las normas sobre bienestar animal debido a la confluencia de varios factores, como el mayor conocimiento en distintas disciplinas relacionadas con los animales de producción (el comportamiento animal, la fisiología del estrés y el manejo correcto de los animales), la relación directa entre estos conocimientos y los niveles de producción estables y competitivos a mediano y largo plazo y una mayor concientización social sobre las necesidades de los animales, así como el rechazo hacia los abusos De esta forma, una vez superadas las necesidades de incremento en el abastecimiento de productos, se han empezado a fijar otros parámetros para cumplir con las demandas sociales en el ámbito de la producción ganadera, uno de esos parámetros, cada día más importante, es el bienestar animal. En esta revisión se intenta destacar la importancia del bienestar de los animales, tanto por la calidad de vida de los mismos, como por su impacto sobre la producción ganadera. Se exponen los principales factores generadores de estrés en ganado, así como los efectos fisiológicos y sus impactos negativos sobre la producción. En vías de brindar una mejor vida al animal y aumentar la calidad del producto, cada vez más países y consumidores imponen exigencias legales y reglamentarias que determinan estándares de bienestar para el manejo animal. Es por todo esto que el bienestar animal adquiere cada vez mayor relevancia en todo el mundo. América Latina se encuentra actualmente atravesando un proceso de adaptación a los nuevos requerimientos internacionales

Analysis of the transcripts encoding for antigenic proteins of bovine gammaherpesvirus 4

The major glycoproteins of bovine gammaherpesvirus 4 (BoHV-4) are gB, gH, gM, gL, and gp180 with gB, gH, and gp180 being the most glycosylated. These glycoproteins participate in cell binding while some act as neutralization targets. Glycosylation of these envelope proteins may be involved in virion protection against neutralization by antibodies. In infected cattle, BoHV-4 induces an immune response characterized by low neutralizing antibody levels or an absence of such antibodies. Therefore, virus seroneutralization in vitro cannot always be easily demonstrated. The aim of this study was to evaluate the neutralizing capacity of 2 Argentine BoHV-4 strains and to associate those findings with the gene expression profiles of the major envelope glycoproteins. Expression of genes coding for the envelope glycoproteins occurred earlier in cells infected with isolate 10/154 than in cells infected with strain 07/435, demonstrating a distinct difference between the strains. Differences in serological response can be attributed to differences in the expression of antigenic proteins or to post-translational modifications that mask neutralizing epitopes. Strain 07/435 induced significantly high titers of neutralizing antibodies in several animal species in addition to bovines. The most relevant serological differences were observed in adult animals. This is the first comprehensive analysis of the expression kinetics of genes coding for BoHV-4 glycoproteins in 2 Argentine strains (genotypes 1 and 2). The results further elucidate the BoHV-4 life cycle and may also help determine the genetic variability of the strains circulating in Argentina.Fil: Romeo, Florencia. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Spetter Lucas, Maximiliano Joaquín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Balcarce; ArgentinaFil: Morán, Pedro. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Pereyra, Susana Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Balcarce; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Balcarce; ArgentinaFil: Perez, Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Verna, Andrea Elizabeth. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Upregulation of interferon-alpha gene in bovine embryos produced in vitro in response to experimental infection with noncytophatic bovine-viral-diarrhea virus

In-vitro fertilization is a routine livestock-breeding technique widely used around the world. Several studies have reported the interaction of bovine viral-diarrhea virus (BVDV) with gametes and in-vitro-produced (IVP) bovine embryos. Since, gene expression in BVDV-infected IVP bovine embryos is scarcely addressed. The aim of this work was to evaluate the differential expression of genes involved in immune and inflammatory response. Groups of 20–25 embryos on Day 6 (morula stage) were exposed (infected) or not (control) to an NCP-BVDV strain in SOF medium. After 24 h, embryos that reached expanded blastocyst stage were washed. Total RNA of each embryo group was extracted to determine the transcription levels of 9 specific transcripts related with antiviral and inflammatory response by SYBR Green real time quantitative (RT-qPCR). Culture media and an aliquot of the last embryos wash on Day 7 were analyzed by titration and virus isolation, respectively. A conventional PCR confirmed BVDV presence in IVP embryos. A significantly higher expression of interferon-α was observed in blastocysts exposed to NCP-BVDV compared to the controls (p < 0.05). In this study, the upregulation of INFα and TLR7 genes involved in inflammatory and immune response in BVDV-infected IVP bovine embryos is a new finding in this field. This differential expression suggest that embryonic cells could function in a manner like immune cells by recognizing and responding early to interaction with viral pathogens. These results provide new insights into the action of BVDV on the complex molecular pathways controlling bovine early embryonic development.Fil: Gonzalez Altamiranda, Erika Analia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; ArgentinaFil: Arias, María E.. Universidad de La Frontera. Núcleo Científico y Tecnológico en Recursos Naturales; ChileFil: Kaiser, Germán Gustavo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; ArgentinaFil: Mucci, Nicolás Crescencio. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; ArgentinaFil: Odeón, Anselmo C.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Felmer Dörner, Ricardo Nicolás. Universidad de La Frontera. Núcleo Científico y Tecnológico en Recursos Naturales; Chil

Genomic analysis of bovine herpesvirus type 4 (BoHV-4) from Argentina: High genetic variability and novel phylogenetic groups

Bovine herpesvirus 4 (BoHV-4) is a γ-herpesvirus that has been isolated both from apparently healthy animals and from cattle with a variety of clinical signs, including post-partum endometritis and abortion. BoHV-4 causes either a persistent or a latent infection in cells of the monocyte/macrophage lineage. Two groups of BoVH-4 strains have been defined based on their restriction patterns: the Movar-like strains (European prototype) and the DN 599-like strains (American prototype). The purpose of the present study was to genetically characterize wild type BoHV-4 strains isolated from vaginal discharges of aborted cows in Argentina. The virus was identified by isolation and nested PCR in all vaginal discharge samples from aborted cows, either as a sole agent or in association with other pathogens. Restriction enzyme profiling and phylogenetic analysis demonstrated that there is a high genetic variability among the studied field isolates. The existence of three groups of strains, which were designated as genotypes 1, 2 and 3, is described. Genotypes 1 and 2 possibly correspond to the Movar-like and DN 599-like groups, respectively, whereas Genotype 3 corresponds to a novel group. Two viral strains did not cluster into any of these three groups, indicating that other genotypes could be circulating in Argentina. These results suggest a complex epidemiological background for the Argentinean BoHV-4 strains, probably influenced by independent events of genetic drift. This hypothesis cannot be rejected based on the available data. However, there is no direct evidence supporting this possibility. Thus, it seems speculative to suggest that interspecific jumps are responsible for the observed phylogenetic grouping. On the other hand, our analyses suggest a geographical structure for the observed viral genotypes, since genotypes 1 and 2 included the European (Movar-like) and American (DN599-like) reference strains, respectively. Geographic dispersion is known to be a driver of herpes viruses diversification, and independent evolution in geographical isolated places ensures the emergence of particular mutations in each location due to genetic drift (Compans, 2007; Zong et al., 1999). Therefore, at this point, the genetic drift hypothesis is the one that requires less ad-hoc considerations and thus, to our understanding, is the one that fits to the findings from this study. The involvement of this genetic variability in the detection and pathogenesis of BoHV-4 remains to be investigated.Fil: Verna, Andrea Elizabeth. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Manrique, Julieta Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Pérez, Sandra Elizabeth. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Leunda, M. R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Pereyra, Susana Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Jones, Leandro Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentin

Identificación y caracterización molecular de virus Orf en mujeres de Sudamérica expuestas laboralmente

Contagious Ecthyma (CE) is a severe exanthematous dermatitis caused by the Orf virus (ORFV) that mainly affects domestic small ruminants such as sheep and goats. It is a worldwide-distributed occupational zoonosis, particularly infecting those in close contact with animals or animal products such as shepherds, farmers and veterinarians, among others. In the present work, we report the first human CE case confirmed in Argentina. A phylogenetic analysis based on four gene sequences of the isolated strain responsible for the disease showed that this isolate grouped with other ORFV sequences that caused reported CE cases in sheep from the same Argentine province. We also sequenced a sample from a Chilean human case reported in 2017, whose phylogenetic analysis showed that it groups together with other Argentine isolates from locations close to the border with Chile.Fil: Peralta, Andrea Verónica. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Flores Olivares, Carlos. Universidad Mayor; ChileFil: Verna, Andrea Elizabeth. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; ArgentinaFil: Gonzalez Altamiranda, Erika Analia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; ArgentinaFil: Odriozola, Ernesto Raul. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Madariaga, Carolina. Universidad Santo Tomás (ust);Fil: Odeón, Anselmo. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: König, Guido Alberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Canton, German. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Sur. Estacion Experimental Agropecuaria Balcarce. Instituto de Innovación Para la Producción Agropecuaria y El Desarrollo Sostenible.; Argentin

Effect of Dexamethasone in Neospora Caninum Seropositive Calves

The aim of this study was to evaluate the effect of Dexamethasone (DXM) on clinical parameters, absolute and differential leukocyte count, specific IgG titers, IFN-γ production and parasitemia in beef calves seropositive to Neospora caninum. Fifteen calves were assigned to four experimental groups as follow: group A: 4 sero- positive calves treated with DXM; group B: 4 seropositive calves without DXM; group C: 3 seronegative calves treated with DXM, and group D: 4 seronegative calves without DXM treatment. The absolute leukocyte count was higher in both groups A and C in the 3rd day after the first dose of DXM mainly due to a significant neutrophilia (p0.05). Similarly, IFN-γ levels did not change among experimental groups (p>0.05). DNA was de- tected in calves from groups A and B at 7 Days Post Administra- tion (dpa) and from group A at 14 dpa. Even when DXM adminis- tration induced hemotological parameter changes, no reactivation of Neospora-infection was observed according to specific IgG titers and presence of the parasite on leukocytes in naturally seropositive beef male calves.Fil: Idarraga Bedoya, S.. Universidad Nacional de Mar del Plata; ArgentinaFil: Armendano, Joaquín Ignacio. Universidad Nacional de Mar del Plata; ArgentinaFil: Gual, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Hecker, Yanina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leunda, M. R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Pereyra, S.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Verna, Andrea Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Campero, C. M.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Odeón, Anselmo Carlos. Universidad Nacional de Mar del Plata; ArgentinaFil: Moore, Dadin Prando. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Controlling Endemic Neospora caninum-Related Abortions in a Dairy Herd From Argentina

After diagnosis of endemic abortions due to neosporosis in a commercial dairy farm, routes of Neospora caninum-transmission were evaluated in order to choose the best strategy for reducing its seroprevalence and related abortions. Fifty two dam-calf pairs were bled at parturition. Additionally, 22 female calves were also sampled at regular 3 month intervals until 18–22 months. N. caninum specific antibodies were assayed by IFAT. Serum samples were tested at a dilution 1:25 for calves before colostrum intake and heifers before mating and 1:100 for multiparous cows. Only serum samples from IFAT seropositive cattle involved in the evaluation of the routes of transmission were assessed by a commercial IgG avidity ELISA. Seropositive cows or heifers were artificially inseminated with semen from Hereford bulls. The progenies from these female animals were sent to a feed lot to produce meat. Different generalized linear models (GLM) were used to study the relationship between abortion, age category, and serostatus. Seropositive heifers were more likely to have a record of abortion (OR 2.7; 95% CI 1.6–4.7). Vertical transmission frequency was 55.5% (5 seropositive calves/9 seropositive cows). Horizontal transmission was 22.7% (5 female calves seroconverted at least one time/22 females calves sampled during 24 months) and these 5 female calves had low avidity. In heifers, both seroprevalence and abortion rates decreased from 22.1 and 8.4% of 475 in 2009 to 6.1 and 4.3% of 578 in 2015, respectively (p < 0.01). Over 5 years, N. caninum-seroprevalence and the related abortions in heifers decreased after the control strategy was assessed.Fil: Lagomarsino, H.. No especifíca;Fil: Scioli, Agustín. No especifíca;Fil: Rodríguez, Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Armendano, Joaquín Ignacio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Fiorani, Franco. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Bence, Ángel. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: García, Joaquín. No especifíca;Fil: Hecker, Yanina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gual, Ignacio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Cantón, Germán. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Odeón, Anselmo. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Campero, Carlos Manuel. No especifíca;Fil: Moore, Dadin Prando. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin