Effect of Exogenous Fibrolytic Enzyme on Digestibility of Ammoniated or

1
Effect of Exogenous Fibrolytic Enzyme on
Digestibility of Ammoniated or Non-ammoniated
Bluegrass Seed Straw Fed to Beef Cattle   J.I.
Szasz, C.W. Hunt, L.R. Kennington, and K.A.
Johnson University of Idaho and Washington
State University
Effect or ammoniation and fibrolytic enzyme on
total-tract NDF digestibility
Introduction Open-field burning of crop
aftermath has been a critically important
management practice for grass seed production.
This practice serves numerous agronomic benefits
and provides for sustained (gt10 yr) seed
production from perennial grass fields.
Environmental and health concerns have resulted
in legislation that restrict the burning of crop
residues in many portions of the NW.
Ammoniation effect P 0.002 SE 0.8
Ammoniated
No Enzyme Enzyme
Non- ammoniated
As a result, bluegrass straw has become a readily
available forage source for livestock producers.
However, high fiber content characteristic of
straws requires that methods be implemented that
improve its feeding value. Research has
indicated that exogenous fibrolytic enzymes may
increase fiber digestibility (Beauchemin et al.,
1995 and Feng et al., 1996). By improving fiber
digestibility, fibrolytic enzymes may have a
practical application in feeding systems that
utilize bluegrass straw.
Research Objective The objective of this research
was to determine the effect of exogenous
fibrolytic enzyme on the digestibility of
ammoniated or non-ammoniated bluegrass seed straw

• Materials and Methods
• 4 x 4 Latin square design metabolism study
• 4 yearling Angus crossbred heifers (mean BW 406
  kg)
• 14 d of diet adaptation followed by 7 d of
  sampling
• 2 x 2 factorial arrangement of treatments
  testing the main effects and interactions of
  ammoniation (5 percent) and exogenous fibrolytic
  enzyme supplementation
• Chemical composition of straws

Effect of ammoniation of bluegrass straw on
ruminal kinetics and ruminal fluid characteristics
(fibrolytic enzyme main effects were not
observed)
Ammoniation effect P lt 0.05

• Exogenous fibrolytic enzyme

• Enzyme application method

SE 0.37
0.001 0.07
0.10