Fatores de risco associados à infecção pelo herpesvírus bovino 1 em rebanhos bovinos da região Oeste do Estado do Paraná

Abstract

The aim of this study was to determine the prevalence of positive herds and to identify the risk factors for BoHV-1 infection in breeding cattle herds in the Western region of Parana State. The statistic delineation, the serum samples and information regarding the selected farms, were the same employed in the study of bovine brucellosis for Parana State in the context of National Program for Control and Eradication of Brucellosis and Tuberculosis. The sampling was performed in two stages. Blood samples were collected from 1930 females aged ≥24 months from 295 non vaccinated herds. Serum samples were tested for antibodies against BoHV-1 using an indirect ELISA. The epidemiological questionnaire was applied on all the selected farms and aimed to obtain epidemiological data. Hundred ninety of the 295 herds were positive for BoHV-1, presenting prevalence of positive herds of 64. 41% [58.65-69.87%]. The number (≥23) of females aged 24 months (OR=2.22; IC: 1.09-4.51), purchased cattle (OR=2.68; IC: 1.48-4.82), use of common grass (OR=5.93; IC: 1.31-26.82), history of abortion in the last 12 months (OR=2.37; IC: 1.09-5.16) and presence of wildlife animals (OR=8.86; IC: 1.11-70.73) were identified as risk factors for BoHV-1 infection in the multivariate logistic regression. These results indicate that BoHV-1 infection is widespread in the studied region and that factors related to the herd characteristic and management are associated with the infection.INDEX TERMS: Prevalence, epidemiology, risk factors, bovine herpesvirus 1, indirect ELISA.

Incidência de Rinotraqueíte Infecciosa Bovina (IBR), Diarreia Viral Bovina (BVD) e Leptospirose em Bovinos Leiteiros da Região Oeste de Santa Catarina - Brasil

“…Del Fava et al (2003 relatam uma prevalência entre 60% e 90% de animais portadores de anticorpos para BVD nos rebanhos mundiais e citam trabalhos que apontam a presença de 60,4% de animais soro reagentes à Leptospirose em 56 propriedades analisadas em seis estados brasileiros. No Estado do Paraná, estudos apontaram um índice de 41,9% de animais e 90,5% dos rebanhos positivos para o vírus causador da Diarreia Viral Bovina (DIAS et al, 2008).…”

Antibodies against Bovine herpesvirus 1 in dairy herds in the state of Espirito Santo, Brasil

“…In the state of Rio Grande do Sul, Holz et al (2009) reported prevalence of 29.2% of seropositive animals for BoHV-1 and BoHV-5. Dias et al (2008) BoHV-1 and BoHV-5 are antigenically related Mahony, 2010). Therefore, they show antigenic cross-reactivity in the diagnosis test used (VN), not being possible to differentiate between antibodies and viral species.…”

“…Studies show that high density herds are associated with greater likelihood of infection by the agent (Miller, 1991;McDermott et al, 1997;Dias et al, 2008). The association between herd size and seropositivity to BoHV-1 can be directly attributed to the often purchase of animals, participation in agricultural events, professional visits and the presence of regular and temporary workers in the properties (Van Schaik et al, 2002).…”

“…A number of studies have been conducted to determine the prevalence of BoHV-1 in Brazilian herds (Ravazzolo et al, 1989;Lovato et al, 1995;Medici et al, 2000;Dias et al, 2008). However, regional variations in rates of prevalence (Kampa et al, 2009) …”

Investigation of the possible role of Chlamydophila abortus in reproductive failures in nrazilian herds of domestic ruminants

“…In some situations, the infection might be present in a latent form, and a seropositive animal might not present any clinical signs (Reinhold et al, 2007). In Brazil, reproductive failures represent the main sanitary problem in cattle herds (Takiuchi et al, 2005;Cortez et al, 2006aCortez et al, , 2006bRufino et al, 2006;Pilz el al., 2007;Dias et al, 2008). Despite being endemic in Brazilian beef and dairy cattle, Leptospirosis, Infectious Bovine Rhinotracheitis (IBR), and the Bovine Viral Diarrhea (BVD) can be controlled through vaccination programs .…”