Summary of Findings
Whole plant corn forage from three genetically different hybrids (coded as 811, 813 and 815) was harvested at three commercial dairies (Elkton, SD; Worthington, MN; Dryden, NY) with a chopper equipped with a Shredlage processor. Each location targeted whole plant dry matter of 33-37%. Twenty pounds of forage was acquired and separated into two 10-lb samples. Each 10-lb sample was placed into a 13-gallon plastic garbage bag. The control treatment was prepared and ensiled before the container with Pioneer Nutrivail feed technology 11CFT was opened to eliminate cross-contamination of treatments. The control forage was mixed by shaking the forage in a partially inflated garbage bag for a minimum of one minute; then 2 lbs of forage was weighed into each of the four vacuum bags. These control bags were vacuum-sealed. The container with Pioneer Nutrivail feed technology 11CFT container then was opened and the inoculant was diluted with water.
The solution containing Pioneer Nutrivail feed technology 11CFT was added to the second garbage bag of forage and the combination was mixed thoroughly by shaking the inoculated forage in the garbage bag. Once mixed, 2 lbs of the 11CFT-treated Shredlage corn forage was weighed into each of four vacuum bags and bags were sealed.
Treatment packets were shipped to the Pioneer Livestock Nutrition Center and stored at room temperature for 90 days. Packets were opened and analyzed by Pioneer research microbiologists to confirm that 11CFT organisms were present in the 11CFT-treatment samples and were not present on the control samples. Samples were oven-dried (< 50°C) and assayed for nutrient content and VFA at Dairyland Laboratories (Arcadia, WI) and by Fermentrics® at RFS Laboratory (Ottawa, Canada). Figures presented are “within hybrid” comparisons as a conservative statistical test of the response of Shredlage silage to inoculation with Pioneer Nutrivail feed technology 11CFT.
Consistent with the activity of the proprietary L. buchneri strain found in Pioneer Nutrivail feed technology 11CFT, Figures 1-3 show that 11CFT samples consistently had more acetate, less lactate and a higher pH than the control silages. This is typical of fermentation with L. buchneri that results in production of acetate and other products that inhibit yeast growth and extend the bunklife of silage. Greater conservation of sugars (P<0.10) in the 11CFT treatment also is indicative of an efficient fermentation and prevention of growth of spoilage organisms.
Figure 1. Acetate in control and 11CFT-treated hybrids harvested with a Shredlage processor
Figure 2. Lactate in control and 11CFT-treated hybrids harvested with a Shredlage processor
Figure 3. Silage pH in control and 11CFT-treated hybrids harvested with a Shredlage processor
Inoculant by silage source interactions existed for many of the Fermentrics parameters in this limited field study, making it impossible to separate main effects (hybrid, 11CFT) clearly. These reflect differences in plant growing conditions, in maturity of the crop at harvest and in relative degree of shredding of the samples.
A consistent increase in the yield of microbial biomass was noted with Pioneer Nutrivail feed technology 11CFT treatment of hybrids harvested with a Shredlage processor (Figure 4). This increase in microbial biomass production matches with the expected activity of 11CFT to liberate hemicellulose bound to lignin and allow more extensive fiber digestion and growth by rumen bacteria. In addition, the increased acetate with 11CFT should extend bunklife of the treated Shredlage.
Figure 4. Microbial biomass (mg/g) in control and 11CFT-treated hybrids harvested with a Shredlage processor
Shredlage is an innovative silage processing procedure that allows theoretical length of cut to be increased up to 30 mm while still delivering a very high degree of kernel processing. Producers and nutritionists have questioned whether application of Pioneer Nutrivail feed technology 11CFT would benefit Shredlage given the increased access to fiber by rumen bacteria associated with the increased “shredding” action from a Shredlage processor. Results of this limited field study confirm that Pioneer Nutrivail feed technology 11CFT had its expected positive effect on fermentation and rumen bacterial growth for corn silage harvested with a Shredlage processor that proved similar to previous findings with Pioneer Nutrivail feed technology 11CFT application to traditionally-processed corn silage.