Ruminal undegradable intake protein fraction of four protein sources: canola meal, dried barley distillers grains, corn distillers, and blood meal.
Diane J. Carroll, Mark R. Keller, Dan Matthiesen, and Todd Koch
Department of Animal Sciences, Oregon State University, March 1997
RESEARCH QUESTION
Dried barley distillers grains are being introduced to the Pacific Northwest as a new source of dietary protein. To incorporate this feed into a dairy ration, it is important to know its ruminal degradability and how it compares to other protein supplements.
The objective of this experiment was to estimate the ruminally undegradable protein fraction of the dried barley distillers and three other protein sources commonly used in the Pacific Northwest.
LITERATURE SUMMARY
An analysis of the ruminal undegradable intake protein fraction of dried barley distillers grains could not be found in the literature. Weiss et al. (1989; J. Dairy Sci. 72:980) reported that a 65% barley to 35% corn dried distillers grain had a composition of 87.5% dry matter, 29% crude protein, 29% acid detergent fiber, and 56% neutral detergent fiber.
STUDY DESCRIPTION
Two cannulated, high-producing, multiparous Holstein cows were housed in a Calan door area for this experiment. Cows were fed a dairy ration supplemented with .25 lb each of blood meal, canola meal, dried barley distillers, and corn distillers grains for two weeks prior to the start of the study. In-situ dacron bags with 1 g of sample were placed in the rumen of cannulated cows at 24, 12, 9, 6, and 3 h before removing bags simultaneously at 0-h.
APPLIED QUESTIONS
How did the feeds rank for crude protein content?
The crude protein content of the feeds, ranked lowest to highest, are: dried barley distillers, corn distillers, canola meal, and blood meal (See Table 1).
How did the feeds rank for by-pass protein content?
The rate of fractional passage was assumed to be .06/h, thus the undegradable intake protein calculated from the in-situ trial from lowest to highest were: canola meal, 32%; dried barley distillers grains, 41%; corn distillers, 43%; and blood meal, 91% (See Table 1).
Table 1. Chemical analysis of four protein sources.
| Canola Meal | Dried Barley Distillers | Corn Distillers | Blood Meal | |
| Dry matter, % | 87.9 | 87.4 | 89.5 | 90.9 |
| - - - - - - - - - - - - - - - - - - - - % DM Basis - - - - - - - - - - - - - - - - - - - - - | ||||
| Crude protein, % | 41.3 | 26.0 | 31.7 | 98.1 |
| Undegraded intake protein (UIP) | 31.7 ± 4.3 | 40.8 ± 3.3 | 42.6 ± .9 | 91.9 ± .7 |
| % of crude protein | ||||
| Range of UIP, % crude protein | 28 to 36 | 37 to 44 | 42 to 44 | 90 to 92 |
| Ether extract, % | 1.9 | 10.4 | 19.9 | 1.1 |
| Acid detergent fiber, % | 19.7 | 19.5 | 9.7 | .2 |
| Neutral detergent fiber, % | 25.1 | 39.75 | 34.5 | 2.2 |
APPLIED QUESTIONS
How do these results compare to other reported values?
Reference values from other UIP studies are listed in Table 2. The NRC (1989) lists the average distillers dried grains with solubles as 47% UIP with a standard deviation of 18% summarized from 4 studies. The corn distillers UIP of 43% and dried barley distillers at 41% fall into this range.
Table 2. Crude protein (CP) and undegradable intake protein (UIP) of concentrates.*1
| INGREDIENT | % CP (DM basis) | UIP, % of CP | INGREDIENT | % CP (DM basis) | UIP, % of CP |
| High Protein Feedstuffs | High Fiber By-products | ||||
| Blood meal | 87.2 | 82 | Brewers grain, dry | 25.4 | 50 |
| Canola meal | 37.4 | 28 | Brewers grain, wet | 25.4 | 45 |
| Cottonseed meal | 44.8 | 43 | Corn gluten feed, dry | 25.6 | 30 |
| Corn gluten meal | 67.2 | 55 | Corn gluten feed, wet | 25.6 | 25 |
| Feather meal | 92.4 | 65 | Distillers grain, dry | 23.0 | 55 |
| Fish meal | 66.7 | 70 | Distillers grain, wet | 23.0 | 50 |
| Meat and bone meal | 54.1 | 65 | Malt sprouts | 28.1 | 40 |
| Soybean meal | 50.0 | 35 | |||
| Grains | |||||
| Corn | 10.0 | 50 | |||
| Barley | 13.5 | 27 | |||
| Oats | 13.0 | 20 | |||
| Wheat | 16.0 | 22 | |||
*1 Adapted from Shaver, R. D. 1989. Proceedings of 1989 Veterinary Nutrition Symposium. August 15-16, 1989. Madison, WI, pp 15-23.
Funds provided by ConAgra, Omaha, NE.
Feeds contributed by John Rosecrans, Top String Nutrition, Hillsboro, OR.
