No abstract

No abstract

ResumoO presente estudo teve como objetivo estimar a prevalência e determinar os principais fatores associados à infecção pelo vírus da diarréia viral bovina (BVDV) no rebanho bovino dos municípios de Santa Vitória do Palmar e Chuí, na região sul do estado do Rio Grande do Sul. Amostras de soro foram submetidas à prova de soroneutralização e, em cada propriedade avaliada, aplicou-se um questionário epidemiológico para investigar fatores que poderiam estar associados à infecção. As amostras de soro foram coletadas em 85 propriedades, cujos animais apresentavam ou não sinais clínicos de infecção pelo BVDV. Das 1.734 amostras de soro analisadas, 1.150 (66,32%) foram positivas com a detecção de bovinos sorologicamente positivos em 70 (82,35%) propriedades. Dentre os fatores avaliados, exploração mista, criação extensiva, realização de ordenha mecânica, uso de inseminação artificial ou de inseminação artificial associada à monta natural, uso de piquete de parição e ausência de assistência veterinária, apresentaram significância estatística (P<0,05) associada à soropositividade. Os resultados obtidos demonstram a expressiva disseminação do BVDV no rebanho bovino dessa região do Rio Grande do Sul. Palavras-chave: Bovinos, problemas reprodutivos, epidemiologia AbstractThis study was performed in order to estimate the prevalence of bovine viral diarrhea virus (BVDV), and to determine the main factors related to the prevalence of the infection in cattle of Santa Vitória do Palmar and Chuí counties, in Rio Grande do Sul State. Sera were submitted to the serum neutralization test and an epidemiological questionnaire was filled out in each herd to investigate variables that could be associated with this infection. The sera samples were collected in 85 farms, with or without clinical signs of BVDV infection. From 1.734 serum samples examined, 1.150 (66.32%) in 70 (82.35%) herds were positive. Variables that were identified as risk factors to seropositivity were mixed (dairy and beef) herds, extensive production, use of mechanical milking, use of artificial insemination or artificial insemination associated with natural service, use of the maternity unit at calving and absence of veterinarian assistance (P<0.05). The results demonstrate the expressive dissemination of the BVDV in cattle of this region in Rio Grande do Sul.

Adjuvants play an important role in vaccine formulations

A presença de anticorpos neutralizantes contra o BHV-1, foi pesquisada pelo teste de soroneutralização (SN) em 2.341 soros, dos quais 747 apresentaram resultado positivo, representando 31,9% de bovinos infectados pelo BHV-1. Os soros foram enviados de 112 propriedades da Região Sul, sendo na maioria rebanhos de gado de corte com problemas reprodutivos. Foram detectados bovinos sorologicamente positivos em 80 propriedades, representando 71,3%, demonstrando a expressiva disseminação do vírus nos rebanhos desta região.

ABSTRACT

No abstract

Meningoencephalitis caused by Bovine herpesvirus type 5 (BoHV-5) is responsible for heavy economic losses in the cattle industry. As in other Alphaherpesviruses, the envelope glycoprotein IV (gD), which mediates penetration into host cells, is one of the major candidate antigens for a recombinant vaccine, since it induces a strong and persistent immune response. The DNA coding for a truncated form of BoHV-5 gD (tgD) has been cloned into the Pichia pastoris expression vector pPICZalphaB to allow protein secretion into the medium. After induction with methanol, a approximately 55kDa protein was obtained. Enzyme deglycosylation with Endo H showed a smaller size band in SDS-PGAE, with approximately 50kDa, suggesting that tgD has N-linked oligosaccharides and that it is not hyperglycosylated. The approximately 55kDa protein was recognized by several polyclonal antibodies, including polyclonal antibody anti-tgD and polyclonal antibodies of different animal species immunized with BoHV-5 and BoHV-1. This is the first report of BoHV-5 gD expression in yeast. It was shown that the recombinant truncated form of BoHV-5 gD has antigenic and immunogenic properties similar to the native BoHV-5 gD. Expression of tgD as a secreted protein allows simple and inexpensive purification methods that can be used for further studies to evaluate its immunogenicity in cattle.