Bovine viral diarrhoea virus infection of alpacas (Vicugna pacos) in the uk

Abstract

Three alpacas (Vicugna pacos) aged two to 22 months with a history of illthrift and diarrhoea were examined postmortem, and tissues were collected for histology, including immunohistochemical labelling for pestivirus antigen, virus isolation and TaqMan reverse transcriptase-pcr assay. Blood samples from two clinical cases and the remaining herd members were tested for bovine viral diarrhoea virus (bvdv) antibody by serum neutralisation, antigen detection and pcr assay. The three affected alpacas were positive for bvdv by pcr of splenic tissue and/or heparinised blood. Non-cytopathic bvdv was isolated from several tissues and plasma of two of the alpacas. dna sequencing and phylogenetic analysis of the viral genome from the pcr product showed that the bvdv was of subgenotype 1b. Immunohistochemical examination of brain tissue was positive in two cases, consistent with a persistent infection. bvdv antibodies were detected in 16 of 25 clinically unaffected alpacas. There was no evidence of persistent infection in the in-contact animals. The source of the infection was not determined.

Disseminated Bovine Viral Diarrhea Virus in a Persistently Infected Alpaca (Vicugna Pacos) Cria

“…4,9 Previous reports on 4 confirmed PI alpacas identified virus in various organs but did not mention reproductive tissues or salivary gland. 5,8,15 Unlike those cases, the cria in this report had disseminated BVDV infections that included parotid salivary gland, esophagus, C1-C3, testes, prostate, and kidneys. Identification of virus in these organs indicates potential routes for transmission through communicative and reproductive behaviors.…”

“…Similar signs have also been reported in other PI alpacas. 5,8,15 The similarities between the disease in cattle and alpacas suggest that the viral pathogenesis could be comparable.…”

“…14,21 However, current evidence suggests that BVDV might be an emerging and significant disease of alpacas. 2,5,8,10,15 The recent increase in cases within alpacas is likely multifactorial and might involve the emergence of a novel viral strain, differences in animal management practices, or increased awareness of BVDV by alpaca owners. The BVDV genome is known to be dynamic, with replication of any isolate giving rise to a viral swarm until a predominant strain emerges, and one of these could have an increased predilection for alpacas.…”

“…6,15 Preliminary research indicates the recent BVDV infections in alpacas have been primarily noncytopathic BVDV-1b strain. 2,5,8,10 Research on PI bovine fetuses and calves has identified virus in all tissues and shedding occurring from multiple sites. 4,9 Previous reports on 4 confirmed PI alpacas identified virus in various organs but did not mention reproductive tissues or salivary gland.…”

Antibodies to Pathogenic Livestock Viruses in a Wild Vicuñe;a (Vicugna vicugna) Population in the Argentinean Andean Altiplano

“…Previous studies have reported serologic evidence of exposure to rotavirus (RV), bovine parainfluenza-3 virus (BPIV-3), bovine herpesvirus-1 (BHV-1), bovine viral diarrhea virus (BVDV), foot-and-mouth disease virus (FMDV), bluetongue virus (BTV), bovine enterovirus (BEV), bovine adenovirus (Badv III), influenza A virus (IAV), and equine herpesvirus-1 (EHV-1) in domestic South American camelids, most from animals without clinical presentation of disease (Fowler, 1998;Mattson, 1994;Saraiva, 2004;Cabello et al, 2006;Celedó n et al, 2006;Evermann, 2006;Parreñ o and Marcoppido, 2006). Viral antigens were detected in domestic came-lids in the presence of clinical signs of disease for BVDV, adenovirus, EHV-1, West Nile virus (Mattson and Baker, 1994;Mattson et al, 2006;Parreñ o and Marcoppido, 2006;Foster et al, 2007), and equine arteritis virus (EAV) (Weber et al, 2006). Studies carried out on wild South American camelids under captive conditions have reported 95% antibody (Ab) prevalence to RV in guanacos from the Argentinean Patagonia region and the first isolation and characterization of RV in guanaco juveniles with acute diarrhea (Parreñ o et al, 2001(Parreñ o et al, , 2004.…”