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

43.9

47.6 47.1

47

50.4

5048.1

52.7

35

40

45

50

55

Deg

radab

ilit

y, %

HD- dry LD- dry HD- 12 LD- 12

3%5%

Control=42.3

Statistically greater than 6 of the 12 ammoniated treatments!

96-hour in situ degradation : bale density, moisture and ammonia level

66.7

71 70.3

70.4

74.676.7

71.3

76.9

55

60

65

70

75

80

Deg

radab

ilit

y, %

HD- dry LD- dry HD- 12 LD- 12

3%5%

Control=61.7

Statistically greater than 7 of the 12 ammoniated treatments!

Any Questions?