The DM levels in total mixed rations were maintained at 62.7, 52.8, and 45.8% by incorporating 38% of the DM from alfalfa silages of twi different DM contents into the ration to determine the effect on milk production and composition when fed to lactating Holstein cows. The alfalfa silages were stored at approximately 25 and 50% DM and harvested from the same field on consecutive days either direct-cut and bagged or wilted overnight before bagging. Silages were used (minimum of 8.5 kg of Dm/d) in a total mixed ration formulated to be isonitrogenous (using cottonseed meal) and isocaloric and fed to 144 lactating cows randomly allotted into three equal groups based on days in milk (initially 33 d), lactation number, and pretrial 3.5% FCM production. Yields of 3.5% FCM were 35.3, 35.7 and 35.4 kg, respectively, for the dry, intermediate, and wet rations and were not significantly different. Consumption of DM tended to decline as DM content of the ration decreased, but the decrease was not significant. Results showed that total mixed ration moisture levels evaluated in this trial had no significant effects on consumption of DM of isonitrogenous rations or milk yield and composition.

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