Distribution of clinical findings and evaluation of infrequent subcutaneous emphysema in naturally infected Simmental and Holstein cattle with bovine ephemeral fever

Bovine ephemeral fever (BEF), also known as three-day sickness, is a vector-borne viral disease of cattle. It causes significant economic losses due to high fever and a sudden decline in milk yield and is characterized by low mortality but high morbidity (80–100%). The aim of this study was to determine the distribution of acute clinical findings in naturally infected Holstein and Simmental cattle with BEF, to evaluate breed-related differences, and to identify subcutaneous emphysema. A total of 32 PCR-confirmed cattle were evaluated. Vital parameters and clinical findings were assessed and recorded within the first 12 hours after the onset of clinical signs. The distribution of clinical findings was as follows (n=32): Appetite was affected in all animals, with complete anorexia observed in 75% of cases; jugular vein distension, recumbency, tremor and salivation (34.4%); lameness (31.2%); mastitis and complete loss of milk production (12.5%); constipation (6.25%); and subcutaneous emphysema (3.1%). No statistically significant difference was found in the distribution of clinical findings between Holstein and Simmental breeds. Subcutaneous emphysema had the lowest incidence among the observed clinical findings. Additionally, jugular vein distension, a clinical finding not commonly described in the literature, was recorded in both breeds during the acute phase of BEF. The combined evaluation of the clinical findings identified in this study may facilitate the diagnosis of BEF, particularly under field conditions, increase clinical suspicion, and support the early initiation of treatment protocols. Additionally, complications such as jugular vein distension, which has not been widely emphasized in previous studies, and subcutaneous emphysema, which is less common, have been observed and should be considered in clinical evaluation.