Winter Feeding Alternatives for Beef Cattle – Utilization of Grass Straw Carl Hunt Department of Animal and Veterinary Science University of Idaho Kristen Johnson Department of Animal Sciences Washington State University

Factors affect ammoniation response: How can we reduce level from 5%? Bale density  Can ammonia penetrate dense bales? Moisture content  Is grass straw too dry?

Treatments: Measure composition and in situ degradablity 2 bale densities  Conventional and 75% 3 moisture levels  Dry, 12 and 18% 3 ammoniation levels  0, 3 and 5%

36-hour in situ degradation: bale density, moisture and ammonia level Control =42.3 Statistically greater than 6 of the 12 ammoniated treatments!

96-hour in situ degradation : bale density, moisture and ammonia level Control =61.7 Statistically greater than 7 of the 12 ammoniated treatments!

Any Questions?