Fatores de risco associados à infecção pelo Herpesvírus Bovino Tipo 1 em rebanhos bovinos leiteiros da região Amazônica maranhense

Abstract

RESUMOO presente estudo teve como objetivo determinar a frequência e os fatores de risco para a infecção pelo Herpesvírus Bovino Tipo 1 (BoHV-1) em fêmeas bovinas leiteiras na região Amazônica maranhense. Amostras de soro de animais não vacinados contra o BoHV-1 e provenientes de 40 propriedades foram submetidas à técnica de ELISA indireto. Em cada propriedade avaliada, aplicou-se ainda um questionário epidemiológico para investigar os fatores de risco que poderiam estar associados à infecção pelo vírus. Das 400 amostras de soro analisadas, 69,25% (n = 277) foram reagentes com a detecção de bovinos sorologicamente positivos em 100% (n = 40) das propriedades. Dentre os fatores de risco avaliados, faixa etária entre 3 a 7 anos, ausência de assistência veterinária e sinais respiratórios apresentaram significância estatística (P < 0,05) associada à infecção pelo BoHV-1. Os resultados do estudo indicam que a frequência de anticorpos contra o BoHV-1 foi elevada na região Amazônica maranhense e que os fatores relacionados às características das propriedades e ao manejo foram associados ao risco de infecção pelo BoHV-1.PALAVRAS-CHAVE: BoHV-1, anticorpos, ELISA, vacas leiteiras, odds ratio. ABSTRACT RISK FACTORS FOR BOVINE HERPESVIRUS 1 INFECTION IN CATTLE HERDS IN THE MARANHENSE AMAZON REGION, BRAZIL.This study was performed in order to determine the frequency of Bovine Herpesvirus 1 (BoHV-1), and the main factors related to the frequency of the infection in dairy cows not vaccinated against BoHV-1 from the Maranhense Amazon region, Brazil. Serum samples from 40 ranches were submitted to indirect ELISA test for detection of BoHV-1 antibodies. An epidemiological questionnaire was applied for each herd to investigate variables that could be associated with this infection. From 400 serum samples examined, 69.25% (n = 277) in 100% (n = 40) of the herds were positive for ELISA. Variables identified as risk factors such of age range of 3-7 years, absence of veterinary assistance and respiratory signs presented a statistical significance (P < 0.05) associated to BoHV-1 infection. These results indicate that BoHV-1 infection is high in the region studied and that factors related to characteristics of the ranches and to the livestock management practices were associated with the risk of infection by BoHV-1.

Soroprevalence of bovine alphaherpesvirus type 1 (BoHV-1) and risk factors associated with dairy properties of the municipality of Senador Guiomard, Acre, Brazil

“…The finding of this study corroborates that one obtained by BEZERRA et al (2012a), that when investigating dairy cattle in the Amazon region of Maranhão the presence of veterinary assistance as a protection factor was identified (OR = 0.37) for the occurrence of viral infection, with significant statistical association (p < 0.05). Similarly, SOUSA et al (2013) also verified the absence of veterinary assistance as a risk factor (OR = 7,714) for increased exposure to the agent (p < 0.05).…”

“…All of the eight investigated properties presented positive animals, and the prevalence distribution by property ranged from 43.3 to 86.2% (Table 1). Similar results were verified by BEZERRA et al (2012aBEZERRA et al ( , 2012b in Maranhão; both studies similarly found seropositive animals for BoHV-1 in all analyzed properties. According to ACKERMANN;ENGELS (2006), once the animal is infected by the alphaherpesvirus, it becomes a carrier and source of infection, which endangers the health of other susceptible animals.…”

“…After collection, the samples were centrifuged at 5,000 G for 10 min to obtain the serum. The serum aliquots were then stored in plastic microtubes and kept at -20°C until the serological test (BEZERRA et al, 2012a).…”

Risk factors associated with BoHV-1 and BVDV seropositivity in buffaloes (Bubalus bubalis) from the State of Paraiba, Northeastern Brazil

“…However, these results indicate that BoHV-1 is broadly disseminated in the region, which reinforces the possibility of these animals acting as sources of infection, mainly when dealing with animals with latent infection, which may disseminate the virus throughout their lives (BEZERRA et al, 2012). For BVDV, the positivity rate found was 8.8%, similar to the results found by Martins et al (2012) in the State of São Paulo (12.9%) and Scheffer (2013) in Rio Grande do Sul (10.8%).…”

Registro de Herpesvírus Bovino (BoHV-1 e BoHV-5) em Rebanho Leiteiro de Propriedades Agro Familiares da Cidade de Alegrete – RS

“…Brasil (BEZERRA et al, 2012), assim como a prevalência de infecções causadas pelo herpesvírus BoHV-5 (COLODEL et al, 2002;RISSI et al, 2006;SALVADORE;LEMOS;RIET-CORREA, 1998).…”