A PROPHYLACTIC STUDY OF PARTURIENT PARESIS IN COWS -Effects of dietary cation-anion balance-

本研究探讨了阳离子交换树脂（Resin）对大鼠、绵羊和牛血液酸碱状态和矿物质浓度的影响，作为预防奶牛分娩轻瘫的可能模型。(1)结果表明，含阳离子交换树脂的饲料可引起代谢性酸中毒，并通过引起骨钙释放而使血中钙浓度升高。(2)绵羊血液pH值和血浆HCO_3水平明显降低，而血浆Cl水平升高。而发生代谢性酸中毒的绵羊无临床症状。(3)牛的结果也与羊的结果相似。总之，这些结果表明，口服树脂能够吸附胃肠道液中的阳离子，并调节血液中的阳离子-阴离子平衡。因此，选择适当的离子交换树脂作为日粮添加剂，可预防产妇轻瘫。

In this study, influences of cation exchange resin (Resin) on acid-base status and mineral concentration of blood were examined in rats, sheep and cattle, as a possible model to prevent parturient paresis in cows.(1) The results in rats indicated that diets containg cation exchange resin induce metabolic acidosis and increase the blood concentration of Ca by causing release Ca from bone.(2) In sheep, the levels of blood pH and plasma HCO_3 apparently decreased, while plasma Cl level increased. However, there were no clinical sighs in the sheep developed metabolic acidosis.(3) The results in cattle was also similar to the resuts observed in sheep.In conclusion, these findings suggested that oral administration of Resin was able to adsorb cations in gastro-enteric fluids enand to regulate cation-anion balances in blood in these animals. Therefore, pertinent selection of ion exchange resin was thought to be utilize as a diet additive to prevent parturient paresis.