Submitted to: Journal of Animal Science
Publication Type: Abstract only
Publication Acceptance Date: 11/17/2008
Publication Date: 3/16/2009
Citation: Caldwell, J.D., Killion, A.E., Hardin, L.A., Coffey, K.P., Young, A.N., Phillip, D., Coblentz, W.K. 2009. Effect of Lactic Acid Lactobacillus Preservative and Moisture Level at Baling on In-situ Digestibility of Crabgrass Hay by Heifers. Journal of Animal Science. 87 (E-Suppl. 3): 94. Interpretive Summary:
Technical Abstract: Common crabgrass (Digitaria ciliaris [Retz.] Koel.) is a warm-season annual that offers an advantage over many perennial warm-season grasses because of its greater nutritive value and high palatability. However, little is known about how baling crabgrass hay at high moisture affects ruminal forage degradation. Our objective was to determine the effects of treating crabgrass at the time of mowing (T) with 81 mL/tonne DM of a solution containing 11% lactic acid and non-viable lactobacillus acidophilus and baling at 2 different moisture levels on ruminal is situ disappearance kinetics. Twelve field plots of crabgrass were assigned randomly to 1 of 4 treatment combinations in a 2 × 2 factorial arrangement. Half of the plots were sprayed with T and half were not treated (U). Within T and U, half of the plots were baled at 18% (M18) moisture and half at 28% moisture (M28). Six bales per plot were selected randomly and stored in insulated 6-bale stacks. Each bale was chopped through a commercial chipper-shreader, mixed thoroughly, and samples were collected after 42-d of storage and ground through a 2-mm screen. Dacron bags containing the ground forages were incubated in the rumen of 6 cannulated heifers (618 ± 18 kg BW; 2/block) for 0, 6, 12, 18, 24, 36, 48, 72, 96, and 120 h and degradation kinetics were determined. The water- soluble fraction was higher (P < 0.05) from M28-T and M18-U compared with M28-U, and effective degradability was higher (P < 0.05) from M28-T than the other treatment combinations. The slowly degraded fraction was greater (P < 0.05) for M28 compared with M18. The undegraded fraction was the lowest (P < 0.05) from M28-T across all treatments. Therefore, treating crabgrass with a lactic acid-lactobacillus product at time of mowing may increase ruminal DM digestibility and allow producers to bale crabgrass hay at higher moisture concentrations.