Evaluation of serum calcium and phosphorus macrominerals changes in downer dairy cows following milk fever current therapy in dairy cattle farms around Tehran

Downer cow syndrome refers to cows that become recumbent and fail to rise; this is a major concern in dairy farms worldwide. The syndrome occurs mainly in the early postparturient period and is caused by several diseases. The most common cause of downer cow syndrome is hypocalcemia (milk fever). This study evaluated the serum concentration of macrominerals(Ca, P) in downer dairy cows that they had treated for milk fever. Blood samples were collected from 30 Holstein downer cows that could not rise 15-18 hours after recumbency and after first treatments. Serum concentration of macrominerals (Ca, P) were determined. In this study the 11 downer cows were hypocalcemic with hypophosphatemic. In the 17 downer cows calcium concentration was below 8mg/dl and in the 21 downer cows phosphorus concentration was below 5.5mg/dl. The serum phosphorus concentratio above 6.5 mg/dl observed in the 7 downer cows that the 6 cows had hyperphosphatemia with hypocalcemia. In this study, hypercalcemia was not in any cases but the 23.3% downer cows had hyperphosphatemia