Molecular characterization of bovine noroviruses and neboviruses in Turkey: detection of recombinant strains

Abstract

To investigate the molecular epidemiology and genetic diversity of bovine enteric caliciviruses, a total of 167 fecal samples from diarrheic calves were screened. Bovine noroviruses (BoNoVs) and neboviruses were detected in 56 (33.5%) and 37 (22.1%) fecal samples, respectively. Sequences of the RdRp and capsid gene of selected BoNoVs showed that the GIII.1 and GIII.2 genotypes were in circulation in Turkey. Two of the BoNoV strains were identified as recombinant strains (GIII. P1/GIII.2). All examined neboviruses possessed a Nebraska-like RdRp gene. The two nebovirus strains were classified into lineage 4 based on phylogenetic analysis of VP1 amino acid sequences. One of them showed evidence of a recombination event within the S domain. This study is thus the first to reveal the presence of the BoNoV GIII.

Prevalence of Bovine Norovirus and Nebovirus and Risk Factors of Infection in Swedish Dairy Herds

“…Age of the calves and number of samples varied substantially between studies. The prevalence of nebovirus in diarrheic calves has been similarly reported: 3% [11], 7% [12], 9% [16], 15% [14], 22% [6,13], 25% [8], and 42% [17]. Generally, a high proportion of BNoV-and nebovirus-positive calves were co-infected with other enteritis agents when such infections were analyzed.…”

“…Most prevalence studies, however, are small or not designed to test such association. The prevalence of BNoV among calves with diarrhea in various countries and herd systems has been highly variable: 3.3% [7], 4% [8], 7.5% [9], 9% [10], 17% [11], 20% [12], 34% [13], 40% [14], 45% [6], and 49% [15]. Age of the calves and number of samples varied substantially between studies.…”

Literature Review: Coinfection in Young Ruminant Livestock—Cryptosporidium spp. and Its Companions

“…Some studies demonstrated coinfections of bovine norovirus and nebovirus in calves with a prevalence ranging from 0.6 up to 10.1% [114,115,117,120]. So far, only a small number of studies have examined the presence of coinfections of bovine norovirus or nebovirus with other diarrhoea-causing agents in diarrhoeic or healthy calves.…”

“…Screening fecal samples of diarrhoeic calves for bovine noroviruses and neboviruses, Karayel-Hacioglu and Alkan (2019) stated that of the infections concurrent with other pathogens, C. parvum spp. was the most commonly detected (46.5%) [120]. Lee et al (2019) examined bovine norovirus in diarrhoeic calves along with 13 other causative agents of diarrhoea and detected a prevalence rate of 4.9%.…”

Viral Enteritis in Cattle: To Well Known Viruses and Beyond

“…Genotype 1 of VP1 can be further subdivided into four lineages that showed both temporal and geographical distribution [109,110]. In addition, recombinant events have been described both in the polymerase and in the capsid regions [111][112][113][114].…”