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Twenty of 60 control cows fed a "normal" diet prepartum developed parturient paresis whereas none of 37 fed a low-calcium (13 to 18 g/cow per day) diet prepartum developed the disease.

60头产前饲喂“正常”日粮的对照奶牛中有20头发生产后瘫痪，而37头产前饲喂低钙（每天每头13至18克）日粮的奶牛中没有一头发生产后瘫痪。

Twenty of 60 control cows fed a "normal" diet prepartum developed parturient paresis whereas none of 37 fed a low-calcium (13 to 18 g/cow per day) diet prepartum developed the disease.