Mengkuil van maïs met aardappelen voor melkvee

In 1987 and 1988, mixed silages of whole crop maize with 23.3 and 28.0 % raw potatoes (DM-basis) respectively, were compared with pure maize silages of the same origin. Chemical composition, nutritive value, preservation, feed intake and milk production by dairy cattle were studied. At harvest the maize had a DM content of 332 and 369 g/kg so that no effluent losses could occur. The potatoes lost quite a lot of water in the silage, but starch content as well as digestibility were not depressed. Consequently the mixed silages had a higher energy content when compared to the control maize silages. The mixed silages were preserved just as well as the control silages. Roughage intake was 0.8 and 1.2 kg DM higher for mixed silages when compared to control silages. Because protein intake was the limiting parameter, only 0.4 and 0.1 kg less concentrate (DM) was given in the mixed silage rations. In both trials total DM-intake was significantly higher for the rations including mixed silage. Milk yield was 0.5 and 0.6 kg lower for mixed silages. On the other hand, milk fat content was 0.1 % units higher in each trial, and also milk protein content was 0.07 and 0.14 % units higher. Finally, milk fat and protein yield were not significantly affected by the ration type. As opposed to the somewhat lower milk production, the cows fed mixed silaged gained more body weight. We may conclude that the storage of raw potatoes in maize silage can be a valuable alternative when compared to the preservation of raw potatoes as such.