Value of Dehydrated Alfalfa in Rations for Lactating Cows

Three experinmnts were conducted using 104 eows to evaluate artificially dehydrated alfalfa as a replacement for 10% of the grain mixture. Corn or sorghum silage was the principal roughage, but small amounts of alfalfa hay were also provided in two of the experiments. In these two experiments, dehydrated alfalfa depressed milk yields when included in meal-type grain mixtures fed at high levels, tIowever, dehydrated alfalfa did not affect yields in the high-grain regimen of the alI-silage trial. Neither did the dehydrated alfalfa affect nfilk yields when included in grain rations fed at normal levels or as a component of a pelleted grain mixture. The alfalfa additive increased silage dry matter intake when included in meal-type grain rations in two of the experiments, but decreased intake in the third experiment involving a pelleted grain ration. Nevertheless, estimated net energy consumed per unit of milk produced was similar for the control and experimental rations. This suggests that reduced milk yield from certain of the dehydrated alfalfa rations was due to insufficient estimated net energy intake.