Temporal dynamics of hepato-metabolic variables, pH metrics and electrolyte homeostasis throughout the transition period in mithun (Bos frontalis) cows

Abstract

Abstract Mithun is a rare bovid exclusively found in high altitude rainforests of northeast India and remains as one of the least studied and neglected species. This is the first study aimed to monitor the effect of transition period on lipid biology, metabolic variables, pH metrics and serum electrolytes of mithun cows reared under semi-intensive system. The study was based on ante-partum (-3 weeks) and post-partum (+1, +2, +3 weeks) appraisal of blood, urine and ruminal fluid from fifteen pregnant mithun cows in last trimester (test group) and fifteen non-pregnant mithun cows (controls). Significantly lowered (P<0.05) total cholesterol and triglycerides were observed in mithun cows immediately after calving however, their levels increased during 1st to 3rd week post-partum. There was a consistent rise (P<0.05) in AST activity at week 0 and +1 while it began to decrease from week +1 to +3. During week 0 and 1, significant decrease (P<0.05) in serum calcium, magnesium, sodium and iron was recorded in transitioning mithun. However, these electrolytes gradually increased from week +1 to +3. Moreover, transitioning cows self-regulated their blood, urinary and ruminal pH without deviation around calving and during the first week of lactation. It is inferred that although transitioning mithun cows are predisposed to mild hypocalcemia, hypomagnesemia and hyponatremia for few weeks post-partum, lipomobilization is a hallmark of their transition period to mitigate energy demands of lactation. Transitioning mithuns exhibit superior metabolic adaptability by rapid restoration of the hepato-metabolic dynamics and pH metrics to normal without supplementation of glucogenic precursors.