Production response of lactating cows fed dried versus wet brewers' grain in diets with similar dry matter content

Twenty-four Holstein-Friesian dairy cows (20 intact and 4 fitted with rumen cannula) during early lactation (56 +/- 25.3 d in milk) were assigned to two treatments to determine intake and production responses to feeding dried and wet brewers' grain. There were two cows fitted with a rumen cannula in each treatment. Cows were fed a total mixed ration twice daily containing either dried or wet brewers' grain at 15% of the dietary dry matter (DM). The diet contained 47% forage and 53% concentrate. The experimental design was a replicated 2 x 2 Latin square with two periods of 5 wk each. First 2 wk in each period were considered as adaptation to diets and data from the last 3 wk were used for treatment comparisons. Dried and wet brewers' diets contained 68.0 and 66.5% DM, respectively. Feeding brewers' grain dry or wet to dairy cows had no influence on feed intake (25.6 vs. 25.1 kg/ d), fat corrected milk yield (40.1 vs. 40.7 kg/d), milk composition and feed consumption. The pH, ammonia, total volatile fatty acids and molar ratios of volatile fatty acids in the rumen fluid were not different between treatments. Fatty acid composition of milk fat from cows fed diets containing dry or wet brewers' grain was identical, except C-18:2 and C-18:3 fatty acids were lower in milk fat from cows fed wet brewers' grain compared with dried brewers' grain. The results from the present study suggest that the performance of cows fed either dried or wet brewers' grain at 15% of dietary DM was similar when diets had the same DM. The average price for dried and wet brewers' grain in the United States from July 2001 to June 2002 was $145.3 and $96.9/metric tonne DM, respectively. Using wet instead of dried brewers' grain will save $49/metric tonne minus the difference in storage costs. Wet brewers' grain can be fed to dairy cows in areas that are close to the brewery and provides nutritive value similar to the dried brewers' grain.