Detection of respiratory and enteric shedding of bovine coronaviruses in cattle in Northwestern Turkey

Abstract

Bovine coronavirus (BCoV) is an important cause of diarrhoea in calves, winter dysentery in adult cattle and respiratory tract disease in feedlot cattle. Serum, faecal and nasal swab samples were collected from a total of 96 cattle with clinical signs in 29 barns of 23 villages in Northwestern Turkey. The cattle were subdivided into 3 distinct age groups (0-30 days old, 4-12 months old and 2-7 years old). An indirect antigen-capture ELISA and an antibody-detection ELISA as well as geometric mean BCoV antibody titres were used to detect BoCV shed in the faeces and in the nasal secretions, respectively. Relationships between BCoV shedding and age group, seroconversion and clinical signs in cattle were also analysed. The rate of faecal shedding of BoCV was 37.1% (13/35) in 0-30 days old calves, 25.6% (10/39) in 4-12 months old feedlot cattle and 18.2% (4/22) in 2-7 years old cows. The overall rate of BCoV faecal shedding was 28.1% (27/96) in the cattle examined. Only one animal in the 4-12 months old age group was found to shed BoCV nasally. The analysis showed that there was a significant difference (P < 0.0001) with respect to faecal shedding between the clinical signs and the age groups. BCoV antibody titre in 50% of all cattle was ≤100 as detected by ELISA while 27.1% of the cattle had high titres ranging between 1,600 and 25,600. The seroconversion rate was 7.3% (7/96) in animals shedding BoCV in the faeces and 42.7% (41/96) in cattle negative for faecal shedding as detected by ELISA, and 20.8% of cattle with no seroconversion shed BCoV in the faeces. There was no statistically significant association between seroconversion and nasal or faecal BCoV shedding. These findings confirm the presence of BCoV infections in Turkey. Further studies are needed to isolate BCoV strains in Turkey and to investigate their antigenic and genetic properties.

Detection of Bovine Coronavirus in Healthy and Diarrheic Dairy Calves

“…Similar results were found in one case–control study involving 380 calves . However, studies including small numbers of calves (n < 100) identified numerical but not statistical association between BCoV in fecal or nasal samples and clinical signs . Discrepancies between studies can be explained, at least in part, by differences in the source population, methodology, especially, the samples size used in the different investigations …”

“…BCoV is the causative agent of diarrhea in newborn calves, winter dysentery in adult cows, and respiratory tract illness in calves and adults . However, some studies have identified numerical but not statistical association between BCoV in fecal or nasal samples and clinical signs . Cases of BCoV enteritis occur in both dairy and beef herds, with clinical signs developing between 5 and 30 days of life and a peak of incidence between days 7 and 10 .…”

Molecular and antigenic characterization of bovine Coronavirus circulating in Argentinean cattle during 1994–2010

“…Other possible explanations for this result could be the lower sensitivity of ELISA compared with RT-PCR assay (Cho et al, 2001a). However, in a survey conducted in Turkey during 2001-2002 using the same indirect antigen-capture ELISA, the BCoV detection rate was 28.1% (Hasoksuz et al, 2005), suggesting that BCoV-associated diarrhea in Argentinean calves may be lower than in other countries.…”

Respiratory Disease Associated with Bovine Coronavirus Infection in Cattle Herds in Southern Italy

“…The BCoV respiratory disease has been described in different areas worldwide, including the United States, 14,19,23 Canada, 8 Turkey, 13 Japan, 17 Finland, 1 and Sweden. 11 In the Finland study, 1 various microorganisms were detected in association with BCoV, including mycoplasmas (mainly Mycoplasma bovis and Mycoplasma dispar), Pasteurella multocida, Mannheimia haemolytica, and Arcanobacterium pyogenes, as well as other viral pathogens, specifically, BPIV3, BRSV, and bovine adenoviruses.…”