Comparison of detection of Bovine virus diarrhea virus antigen in various types of tissue and fluid samples collected from persistently infected cattle.

Bovine viral diarrhea viruses are economically important pathogens of cattle. Most infections in susceptible animals are acquired from animals persistently infected with the virus. Surveillance programs rely on skin biopsies of persistently infected (PI) cattle to detect the infection. The purpose of this study was to compare antigen capture enzyme-linked immunosorbent assay (ACE) testing results using different types of samples from PI animals. The intent was to determine comparative detection rates in types of samples that are frequently submitted to diagnostic laboratories for evaluation of cases of unknown etiology or samples that could be easily collected for Bovine viral diarrhea virus (BVDV) screening. Eight types of samples were collected from 40 PI animals. The sample types were ear notches, serum, nasal swabs, conjunctival swabs, oral swabs, rectal swabs, vaginal/preputial swabs, and a tail skin fold biopsy. Each type of sample (n  =  8) for each animal (n  =  40) was evaluated with a commercial ACE kit. When using ACE, tail-skin fold and nasal swab samples were 100% sensitive compared with results using ear notches. Sensitivity using other samples was as follows: serum and vaginal/preputial swabs, 92%; conjunctival swabs, 64%; rectal swabs, 10%; oral swabs, 8%. Testing of tail skin fold biopsies, nasal swabs, and ear notch samples resulted in reliable results. In contrast, other sample types were unreliable for diagnosis of persistent infection in calves.