The effects of fasting on some biochemical factors of liver, serum and clinical signs in cattle

BACKGROUND: Fasting is an alternative method to induceanorexia. OBJECTIVES: The biochemical factors of liver andserum and clinical signs were measured and documented in fivenon-lactating, non-pregnant cows following eight days of fasting.METHODS:Five crossbred, non-lactating, and non-pregnantcattle were used in this study. They were fasted for 8 days_ totalfood deprivation; however, they had free access to water. Liverbiopsies were carried out one day before food deprivation (day0) and 8 days after food deprivation by ultrasound-guidedbiopsy. Blood samples were taken from the jugular vein beforeand during fasting. The concentrations of triglyceride (TG), totallipids, glycogen, phospholipids, and total protein in liver andNEFA, BHBA, TG, total cholesterol, glucose, total lipid, APOA1, and APO B in blood serum were measured and compared.RESULTS: The results of this study showed that fasting for 8 daysreduces respiratory rate by 52% and heart rate by 12.5% and hasno significant effect on rectal temperature. The concentrations ofthe liver triglyceride (TG) and glycogen significantly increased(p=0.046) and decreased (p=0.007) on day 8, respectively. Therewere no significant differences in the content of liverphospholipids (p=0.83), total lipids (p=0.29), and total protein(p=0.23). The serum concentrations of NEFA and BHBAincreased significantly (p=0.008) at the end of fasting period. Nosignificant differences in the concentrations of serum TG(p=0.057), total cholesterol (p=0.93), glucose (p=0.108), totallipid (p=0.27), APO A1 (p=0.762), and APO B (p=0.92) werenoticed on days 0 and 8. CONCLUSIONS: The results of thepresent study showed that fasting, like anorexia (as a result ofdiseases), induces fat mobilization from adipose tissue inresponse to the induced negative energy balance.