CHANGES IN SERUM ELECTROLYTES OF HOLSTEIN COWS WITH PERIPARTURIENT DISEASES

Blood samples were obtained from 85 Holstein cows in a dairy farm during the two months prepartum, at parturition and the two months postpartum. The electrolytes measured were sodium, potassium, chloride, calcium, inorganic phosphorus, magnesium and iron. At parturition, the levels of chloride, calcium, inorganic phosphorus and iron were lower (P<0.05) than values at other periods. No significant difference was observed in serum sodium and potassium levels (P>0.05). Concentration of magnesium was greater (P<0.05) at parturition as compared with pre- and postpartum periods. Illness or disease occurred in 12 out of 85 cows at parturition or thereafter. Postparturient metritis, uterine prolapse, milk fever, retained placenta and mastitis were diagnosed. Under the disease conditions, the concentrations of sodium and chloride did not change. In cows suffering from postparturient metritis and uterine prolapse, the concentrations of calcium and phosphorus decreased but concentration of magnesium and iron increased as compared to values at the time of parturition. In milk fever and retained placenta, the concentration of calcium and phosphorus decreased as compared to values at the time of parturition. In contrast, the concentration of magnesium increased in milk fever and retained placenta. Concentration of potassium was also decreased in milk fever. The results of this study indicated that the most important change in serum electrolytes is at parturition. Also, there is a significant alteration in serum electrolytes of cows with periparturient diseases.