Antigenic variability in bovine viral diarrhea virus (BVDV) isolates from alpaca (Vicugna pacos), llama (Lama glama) and bovines in Chile

Llamas and alpacas are domesticated South American camelids (SACs) important to ancestral population in the Altiplano region, and to different communities where they have been introduced worldwide. These ungulates have shown to be susceptible to several livestock viral pathogens such as members of the Pestivirus genus and mainly to bovine viral diarrhea virus (BVDV). Seventeen Chilean BVDV isolates were analyzed by serum cross neutralization with samples obtained from five llama, six alpacas, three bovines, plus three reference strains belonging to different subgroups and genotypes. The objective was to describe antigenic differences and similarities among them. Antigenic comparison showed significant differences between different subgroups. Consequently, antigenic similarities were observed among isolates belonging to the same subgroup and also between isolates from different animal species belonging the same subgroup. Among the analyzed samples, one pair of 1b subgroup isolates showed significant antigenic differences. On the other hand, one pair of isolates from different subgroups (1b and 1j) shared antigenic similarities indicating antigenic relatedness. This study shows for the first time the presence of antigenic differences within BVDV 1b subgroup and antigenic similarities within 1j subgroup isolates, demonstrating that genetic differences within BVDV subgroups do not necessary corresponds to differences on antigenicity.