Circadian gene expression in peripheral blood of Bos taurus under different experimental condition

The aim of the study was to investigate clock gene expression in Bos taurus and the alteration of that during two pathological conditions, evaluating the daily expression pattern of four clock genes (Per2, Cry2, Bmal1, Clock) in peripheral blood cells. Five healthy cows, five affected by Brucellosis (BR) and five affected by Bovine Viral Diarrhoea-Mucosal Disease (BVD-MD) were housed in indoor stalls under natural spring conditions, blood samples were collected at 4 h intervals over a 24 h period. Statistical analysis showed rhythmic expression of clock genes mRNAs in healthy cows. Cows affected by BR did not show any rhythmic expression of clock genes mRNAs, cows affected by BDV mRNA levels of Bmal1, Clock and Cry2 changed during the day. These findings highlighted that circadian system could be involved in homeostasis alteration and that clock genes could be considerate as regulatory genes or early response genes during inflammation, so, their regulation should be evaluated in health research and treatment.