Bovine Coronavirus-Associated Winter Dysentery in Cattle: Clinical, Molecular, Hematological, and Some Biochemical Findings from a Herd Outbreak

BACKGROUND and OBJECTIVE: Winter dysentery is

an acute and highly contagious disease of adult

cattle associated with bovine coronavirus (BCoV),

and it usually involves the digestive system and

sometimes the respiratory tract. This study aimed to

evaluate the clinical, molecular, hematological, and

biochemical findings observed during a BCoV

associated winter dysentery outbreak in a cattle

herd and to assess the potential supportive value of

serum iron and selected laboratory parameters in affected animals.

MATERIALS and METHODS: The animal material of

this study consisted of 23 cattle from the same herd,

including 14 clinically affected animals and 9

clinically healthy controls. Blood samples (10 mL)

were collected from the vena coccygea of all

animals. One portion was transferred into K3-EDTA

tubes for hematological analysis, whereas the

remaining portion was placed into gel and clot

activator tubes for serum biochemical analyses,

including serum iron measurement. In addition,

nasal swabs and stool samples were taken from

clinically affected animals and sent to a virology

laboratory for molecular diagnosis. They were

analyzed by PCR for the coronavirus nucleoprotein

gene region.

RESULTS: Clinically affected cattle predominantly

exhibited bloody, mucoid diarrhea, while some also

showed cough, nasal discharge ranging from serous

to mucopurulent, and anorexia. Of the 14 clinically

affected animals, 9 (64.3%) were positive for BCoV by

PCR in at least one sample type. A total of 12 samples

tested positive, and 3 animals showed concurrent

positivity in both respiratory and digestive samples,

suggesting involvement of both systems in some

cases. Hematological analyses showed that white

blood cell, lymphocyte, eosinophil, and basophil

counts were significantly lower in affected cattle

than in healthy controls, whereas mean platelet

volume and plateletcrit values were significantly

higher. Biochemical analyses revealed significantly

lower serum iron and total protein concentrations in

affected animals (p<0.05).

CONCLUSIONS: The findings support a herd-level

outbreak of BCoV-associated winter dysentery and

indicate that BCoV may be present in both digestive

and respiratory samples of clinically affected cattle.

The high proportion of PCR-positive animals and the

concurrent positivity in both sample types in some

cases suggest that BCoV played an important role in

the outbreak and may be associated with

multisystemic

involvement.

The

observed

hematological and biochemical alterations further

indicate systemic effects of the disease. Decreased

serum iron may represent a supportive laboratory

finding, although its diagnostic value should be

confirmed in larger studies including PCR

confirmed cases.