Prevalence of Bovine herpesvirus type 4 in aborting dairy cows

Abstract

Bovine herpesvirus type 4 (BHV-4) is related to many different conditions: infertility, postpartal metritis, vulvovaginitis, mastitis, encephalitis, calf pneumonia, keratoconjunctivitis, cutaneous lesions, digital dermatitis and abortion. In this study a retrospective PCR examination of 100 extracted DNA samples from aborting cows was performed in order to determine: prevalence of BHV-4 in abortive cattle, whether coinfections BHV-4 with other abortifacient pathogens are present in the same sample and to determine the month of gestation when BHV-4 associated abortions were detected. Out of 100 examined samples, the BHV-4 genome was detected in 21 samples (21%). In two samples we detected coinfection of BHV-4 with bovine viral diarrhea virus (BVDV) and in one with Neospora caninum. Most of the BHV-4-associated abortions were detected during the seventh month of gestation. It was concluded that an active BHV-4 infection was present among cows that aborted on the farms examined. The high prevalence of the BHV-4 genome in abortion material suggests that this virus may have cause the abortions. Further studies and examinations are needed to establish causative connection between presence of BHV-4 and abortion.

Bovine herpes virus type-4 infection among postpartum dairy cows in California: risk factors and phylogenetic analysis

“…Therefore, comparability of prevalence records from different geographic places and dairy practices should take in account the diagnostic tools used to detect the virus. The PCR-based 22.3% prevalence of BoHV-4 recorded in our study is comparable with 21.0% reported from aborting dairy cows in Serbian farms that employed a similar diagnostic test [18]. Serological tests detected as high as 84.37% of BoHV-4 antibodies from cows with post-partum metritis [23].…”

“…Likewise, concurrent involvement of BVDV and BoHV-4 in post-partum metritis was detected in one uterine sample. Similar studies have documented BVDV as a co-infecting virus in BoHV-4-associated abortion in Serbian dairy herds [18] and endometritis in post-partum cattle from North America [6]. Another study from North America has documented coinfection of foetus with BoHV-4 and BVDV [37].…”

“…Detection of BoVH-4 and other co-infecting viruses including bovine viral diarrhoea virus (BVDV) [18], bovine herpes virus-1 (BoHV-1), bovine herpes virus-2 (BoHV-2) and parapox virus (PPV) in uterine/vaginal samples was confirmed by real-time (RT) PCR at the CAHFS laboratory, Davis. The assay targeted three open reading frames [19] of the viral genome (ORF 3 – encoding thymidine kinase, ORF 8 – encoding glycoprotein B and ORF 22 – encoding glycoprotein H).…”

An assessment of bovine herpes virus 4 as a causative agent in abortions and neonatal death

“…Bovine herpes virus 4 is a co-factor in cattle abortion cases along with other pathogens, including viruses, bacteria and protozoans. They also play a clear role in certain other reproductive disorders such as endometritis (Chastant-Maillard 2015; Cvetojević et al 2016;Frazier et al 2002;Reed, Langpap & Bergeland 1979). Researchers have, therefore, focussed on detecting BoHV-4 in semen, uterine and blood samples from aborting cows in herds with postpartum metritis (Cvetojević et al 2016;Dağalp et al 2012;Nikolin et al 2007;Nikolin, Vesna & Radosavljević 2008).…”

“…They also play a clear role in certain other reproductive disorders such as endometritis (Chastant-Maillard 2015; Cvetojević et al 2016;Frazier et al 2002;Reed, Langpap & Bergeland 1979). Researchers have, therefore, focussed on detecting BoHV-4 in semen, uterine and blood samples from aborting cows in herds with postpartum metritis (Cvetojević et al 2016;Dağalp et al 2012;Nikolin et al 2007;Nikolin, Vesna & Radosavljević 2008). However, the connection between BoHV-4 and abortions remains unclear because the virus has been isolated from both diseased and healthy cattle (Czaplicki & Thiry 1998;Deim, Szeredi & Egyed 2007;Leboeuf 2013).…”