جستجوی مقالات مرتبط با کلیدواژه « منیزیوم » در نشریات گروه « دامپزشکی »

Clinical and subclinical hypocalcemia are two factors of economic losses in herds, and occurs when dairy cows are unable to replace the calcium lost through colostrum and milk secretion. This study was performed to evaluate occurrence of milk fever, subclinical hypocalcemia and calcium related diseases in high yielding dairy cows. In this study, blood samples of 18 primiparous and 18 multiparous cows in transition period in two farms with the same management status were taken. Dairy cows received limited calcium and phosphorus diet, from 21 days prepartum until parturition and lactation diet according to nutritional requirements after parturition. Serum level of calcium, phosphorous and magnesium were measured with routine laboratory methods. Base on cut point of calcium (8.5 mg/kg), subclinical hypocalcemia in primiparous and multiparous cows before parturition was 16.7 and after parturition was 11.1 and 16.7 %. The frequency of milk fever, retained fetal membranes, metritis and displaced abomasum of all parturition in 1 year were 1.3, 12.6, 5.9 and 0 percent, respectively. Results show that parity dosn’t have significant effect on subclinical hypocalcemia occurrence in cows that consumed limited calcium and phosphorus diet in close up period. Also regardless of parity limited calcium and phosphorus diet in close up period have a positive effect on prevention of milk fever.