Gerloff B J, Swensen E P
Seneca Bovine Services, Marengo, IL 60152, USA.
J Am Vet Med Assoc. 1996 Mar 1;208(5):716-9.
Because of a mixing error at a local feed mill, a diet marginally deficient in phosphorus, compared with recommendation from the National Research Council, was fed to a high-producing dairy herd for 5 months. Two mature cows in early lactation became recumbent. Serum phosphorus concentration in 1 cow was low (1.8 mg/dl), but was not measured in the other cow. Ten other high-producing, first-lactation cows in the herd developed severe lameness. Results of analysis of rib bone samples from the recumbent cows were consistent with changes associated with demineralization. Bone ash, calcium, phosphorus, and magnesium concentrations were lower than published ranges for healthy cattle. Serum calcium, phosphorus, and magnesium concentrations in 8 unaffected cows were normal. For 6 unaffected cows, mean serum hydroxyproline concentration was higher during the period that the phosphorus-deficient diet was fed than when an adequate diet was fed. Moderate (15%) restrictions in dietary phosphorus intake, compared with National Research Council recommendations, can possibly result in health problems in high-producing dairy cattle.
由于当地一家饲料厂的混合错误，给一群高产奶牛饲喂了一种磷含量略低于美国国家研究委员会建议水平的日粮，持续了5个月。两头处于泌乳早期的成年母牛躺卧不起。其中一头母牛的血清磷浓度较低（1.8毫克/分升），但另一头母牛未进行测量。该牛群中另外10头高产的头胎母牛出现了严重跛行。对躺卧母牛的肋骨样本分析结果与脱矿质相关变化一致。骨灰、钙、磷和镁的浓度低于已公布的健康牛的范围。8头未受影响母牛的血清钙、磷和镁浓度正常。对于6头未受影响的母牛，在饲喂缺磷日粮期间，血清羟脯氨酸平均浓度高于饲喂充足日粮时。与美国国家研究委员会的建议相比，日粮中磷摄入量适度（15%）受限可能会导致高产奶牛出现健康问题。
