BackgroundBovine herpes virus 5 (BoHV-5), known as bovine encephalitis herpes virus, is a neurovirulent alpha herpes virus that causes fatal meningoencephalitis in calves and significant economic losses in the cattle industry.This virus may also be associated with bovine herpes virus 1 (BoHV-1), which commonly affects the respiratory and reproductive systems of the same host [1][2][3].Molecularly, the envelope of BoHV-5 is formed by the glycoproteins gB, gC, gD, gE, gG, gK, gH, gI, gL and gM and the proteins Us9 and α-tif.The gC protein has been associated with the introduction of the virus in the brain, and gD is the receptor that facilitates binding to the host cell, initiating a replication process similar to those of other alpha herpes viruses [4][5][6][7][8].Although present in both BoHV-1 and BoHV-5, the gE amino acid sequence differs significantly between these viruses, causing a major difference in the nervous system invasion pattern and latency of 6].The Us9 protein of BoHV-1 is crucial for reactivation in the trigeminal ganglia, and the same protein in BoHV-5 has an important role in viral transport from olfactory receptor neurons to the olfactory bulb [9].From an epidemiological standpoint, a viral neutralization test against BoHV-1 can be useful for suspected infection with BoHV-5 [10]; however, because they share many structural, biological, antigenic and molecular characteristics, cross-reactions may occur between the two viruses, which hinder the evaluation of their serological prevalence [11][12][13].