Conservation of pressed brewers gains and their utilization in cattle feeding - 2. Use of pressed brewers ensiled grains or brewers dried grains in dairy cows

In the present study the influence of pressed brewers ensiled grains on digestibility, feed intake und milk yield was tested in comparison with a conventional protein concentrate (25 % soybean meal, 25 % rapeseed meal, 25 % faba beans, 25 % peas) as well as with brewers dried grains. In the experiment 12 cows were used in a latin square design with 4 replications. One period lasted for 3 weeks. The forage was composed of 35 % hay and 65 % maize silage. The forage ration fed ad libitum was supplemented according to requirements by an energy and protein concentrate (PKF) or pressed brewers ensiled grains (BTS) or brewers dried grains (BTT). The digestibility of OM with sheep was 59.6 % with BTS and 62.3 % with BTT. When feeding pressed brewers ensiled grains the forage and energy intake was significantly reduced from 102.3 to 93.8 MJ NEL. The milk yield of the BTS group was 0.6 kg ECM lower compared to the control group PKF (20.0 kg), but this difference was not significant. In conclusion, the present results as well as the literature data indicate that a slight reduction of feed intake has to be expected when pressed brewers ensiled grains are fed. On the one hand this is due to the lower degradation rate and digestibility of this feed stuff. On the other hand ensiling may have a negative effect. The low rate of protein degradation has to be regarded as a positive factor as it results in a higher supply of undegraded protein to the host animal and (partly) compensates for the lower energy supply.