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Brown C.,West Virginia University | Griggs T.,West Virginia University | Keene T.,Mycogen Seeds | Marra M.,U.S. Army | Skousen J.,West Virginia University
Bioenergy Research | Year: 2016

Growing food crops for biofuel on productive agricultural lands may become less viable as requirements to feed a growing human population increase. This has increased interest in growing cellulosic biofuel feedstocks on marginal lands. Switchgrass (Panicum virgatum L.), a warm-season perennial, is a viable bioenergy crop candidate because it produces high yields on marginal lands under low fertility conditions. In other studies, switchgrass dry matter (DM) yields on marginal croplands varied from 5.0 to 10.0 Mg ha−1 annually. West Virginia contains immense areas of reclaimed surface mined lands that could support a switchgrass-based biofuel industry, but yield data on these lands are lacking. Field experiments were established in 2008 to determine yields of three switchgrass cultivars on two West Virginia mine sites. One site reclaimed with topsoil and municipal sludge produced biomass yields of 19.0 Mg DM ha−1 for Cave-in-Rock switchgrass after the sixth year, almost double the varieties Shawnee and Carthage, at 10.0 and 5.7 Mg ha−1, respectively. Switchgrass yields on another site with no topsoil were 1.0 Mg ha−1 after the sixth year, with little variation among cultivars. A second experiment was conducted at two other mine sites with a layer of topsoil over gray overburden. Cave-in-Rock was seeded with fertilizer applications of 0, 34, and 68 kg N-P2O5-K2O ha−1. After the third year, the no fertilizer treatment averaged biomass yields of 0.3 Mg ha−1, while responses to the other two rates averaged 1.1 and 2.0 Mg ha−1, respectively. Fertilization significantly increased yields on reclaimed mine soils. Where mine soil fertility was good, yields were similar to those reported on agricultural soils in the Northeastern USA. © 2015, The Author(s). Source

Lim J.M.,University of Delaware | Nestor K.E.,Mycogen Seeds | Kung L.,University of Delaware
Journal of Dairy Science | Year: 2015

We evaluated the effects of corn silage hybrids [control vs. brown midrib (BMR)] and the proportion of corn silage in rations on the performance of high-producing dairy cows. The chemical composition of the corn silages was similar except for lignin, which was higher in the control hybrid [3.09%, dry matter (DM) basis] compared with the BMR hybrid (2.19%). The 30-h in vitro neutral detergent fiber (NDF) digestibility was also higher (62.8% of NDF) in the BMR hybrid than in the control hybrid (52.2%). Twenty-seven Holstein cows were fed 1 of 3 diets comprising 62% forage and 38% concentrate (DM basis) containing 35% (DM basis) corn silage from the control hybrid (NLO), 35% of the BMR hybrid (BLO), or 50% of the BMR (BHI). Cows were fed the diets in a replicated 3 × 3 Latin square design with 28-d periods. Intake of DM was similar among treatments but milk production was greater for cows fed BLO (50.1. kg/d) and BHI (51.1. kg/d) than for NLO (47.9. kg/d). Milk fat percentage was lower for cows fed BHI (3.37%) than for those fed BLO (3.55%) and NLO (3.56%) but yield of milk fat was similar among treatments. Yield and percentage of milk protein was higher for cows in BHI compared with NLO. The concentration of milk urea N was lower in cows fed BHI (14.0. mg/dL) than in those fed NLO (14.7. mg/dL) and intermediate for BLO (14.5. mg/dL). The yield of 3.5% fat-corrected milk was higher in cows fed BLO (50.2. kg/d) than in NLO (48.2. kg/d) and was intermediate for BHI (49.8. kg/d). The total-tract digestibility of dietary DM, organic matter, starch, and crude protein was lower for cows in NLO compared with the other treatments. The total-tract digestibility of NDF was highest for BHI (54.4%), intermediate for BLO (50.9%), and lowest for NLO (43.2%). We conclude that BMR corn silage can be included in rations at moderate and high proportions of a total ration, resulting in high levels of milk production. © 2015 American Dairy Science Association. Source

Der Bedrosian M.C.,University of Delaware | Nestor K.E.,Mycogen Seeds | Kung L.,University of Delaware
Journal of Dairy Science | Year: 2012

The objective of this study was to evaluate the effect of hybrid, maturity at harvest [dry matter (DM) content], and length of storage on the composition and nutritive value of corn silage. The plants used in this study included a normal (NORM) and a brown midrib (BMR) hybrid, harvested at 32 or 41% DM and ensiled for various lengths of time (0 to 360. d) without inoculation. Measurements included nutrient analysis, fermentation end products, in vitro digestion of NDF (NDF-D, 30. h), and in vitro digestion of starch (7. h). The concentration of acetic acid increased with length of storage for all treatments, specifically increasing as much as 140% between. d 45 to 360 for 32% DM BMR silage. Small changes in lactic acid and ethanol were noted but varied by DM and hybrid. When averaged across maturities and length of storage, compared with NORM, BMR silage was lower in concentrations of lignin, crude protein, neutral detergent fiber, and acid detergent fiber, but higher in starch. On average, NDF-D of both hybrids was not affected by length of storage between 45 and 270. d. The NDF-D was markedly greater for BMR than NORM after all times of storage. Increasing maturity at harvest generally did not affect the NDF-D of NORM, with the exception that it was slightly lower for the more mature plants at 270 and 360. d. In contrast, the NDF-D of BMR was lower in more mature silage by approximately 5 percentage units from 45 to 360. d. The concentration of starch for 32% DM NORM was lower (21%) than other treatments (31 ± 3%; mean ± SD) at harvest. This finding was probably the cause for starch digestibility to be highest in 32% DM NORM samples at. d 0 (about 80%) and lower (65 to 68%) for other treatments. Concentrations of soluble N and ammonia-N increased with length of storage, indicating that proteolytic mechanisms were active beyond 2 to 3 mo of storage. The in vitro digestion of starch generally increased with length of storage, probably as a result of proteolysis. Although active fermentation occurs for only a relatively short time in the silo, many metabolic processes remain active during long-term storage. Changes in the nutritive value of corn silage during storage should be accounted for during ration formulations. © 2012 American Dairy Science Association. Source

Holt M.S.,Utah State University | Eun J.-S.,Utah State University | Thacker C.R.,Utah State University | Young A.J.,Utah State University | And 2 more authors.
Journal of Dairy Science | Year: 2013

This experiment was conducted to test a hypothesis that lactating dairy cows fed 35% brown midrib (BMR) corn silage and 25% alfalfa hay (dry matter (DM) basis) would consume more DM around peak lactation compared with those fed conventional corn silage (CS), resulting in longer peak milk production. Twenty-eight multiparous Holstein cows were used starting at the onset of lactation through 180. d in milk (DIM). Treatments were formulated to maintain a forage-to-concentrate ratio of 60:40, differing only in the CS hybrids used. Two dietary treatments were assessed in a completely randomized design: total mixed ration based on conventional CS (CCS) and total mixed ration based on BMR silage. Through peak lactation (1-60. DIM), DM intake was not different between dietary treatments, whereas DM intake post-peak lactation (61-180. DIM) tended to increase by feeding the BMR diet compared with the CCS diet (25.8 vs. 24.7. kg/d). Cows fed the BMR diet tended to lose less body weight through peak lactation compared with those fed the CCS diet (-0.22 vs. -0.52. kg/d). Although milk yield was not different between dietary treatments through peak lactation, milk yield post-peak lactation increased by feeding the BMR diet compared with the CCS diet (41.0 vs. 38.8. kg/d). Yield of 3.5% fat-corrected milk was similar between dietary treatments throughout the experiment (41.4. kg/d, on average), but milk fat concentration decreased by feeding the BMR diet compared with the CCS diet post-peak lactation (3.47 vs. 3.80%). Overall milk protein concentration was similar between dietary treatments throughout the experiment (2.96%, on average), whereas milk protein yield tended to be higher for the BMR diet post-peak lactation compared with the CCS diet (1.19 vs.1.13. kg/d). Feeding BMR silage with a high dietary concentration of alfalfa hay maintained more body weight, but did not affect milk production through peak lactation; however, cows fed the BMR diet post-peak lactation consumed more feed and maintained longer peak milk yield, leading to greater overall milk production and milk protein yield. © 2013 American Dairy Science Association. Source

Stone W.C.,Diamond V | Chase L.E.,Cornell University | Overton T.R.,Cornell University | Nestor K.E.,Mycogen Seeds
Journal of Dairy Science | Year: 2012

The objective of this study was to evaluate transition cow performance when brown midrib corn silage (BMRCS; Mycogen F2F444) was included in the diet during the transition period, and to determine if any production response occurring during the first 3. wk of lactation would persist from wk 4 to 15 when a common diet was fed. Seventy Holstein dairy cows were blocked by parity (either second or third and greater) and calving date and randomly assigned to the CCS (a mixture of varieties of conventional corn silage) or BMRCS treatment. Diets were formulated with the objective of keeping all ration parameters the same, with the exception of neutral detergent fiber digestibility. Neutral detergent fiber digestibility values (30 h) for CCS and BMRCS averaged 56.8 and 73.8%, respectively. Prepartum rations contained 47% corn silage, 18% wheat straw, 7% alfalfa haylage, and 28% concentrate, and averaged 45% neutral detergent fiber (DM basis). Postpartum rations contained 40% corn silage, 15% alfalfa haylage, 1% straw, and 44% concentrate. Milk weights (3×/d) and dry matter intake were recorded daily, and milk composition was measured weekly. Cows fed BMRCS had higher dry matter intake during the 2-wk period before calving (14.3 vs. 13.2. kg/d) and the 3-wk period after calving (20.1 vs. 18.1. kg/d) than did cows fed CCS. Yields of milk, solids, and lactose were increased, whereas a trend was observed for a reduction in somatic cell counts and linear scores in the postpartum period for cows receiving BMRCS during the transition. A significant carryover effect of BMRCS was observed on production from wk 4 to 15 when the common diet was fed, with yields of protein (1.36 vs. 1.30. kg/d), lactose (2.24 vs. 2.12. kg/d), and solids (5.82 vs. 5.51. kg/d) increasing significantly, and yields of fat-corrected milk, energy-corrected milk, and fat tending to increase during this period for cows that had been fed BMRCS. The increased intakes during the last 2. wk of the prepartum period in the BMRCS treatment were likely because of a reduction in fill, whereas the increased intakes in the postpartum period in cows fed the BMRCS were either because of the higher intakes during the prepartum period or because of a reduction in fill limitations in the postpartum period. The carryover response in wk 4 to 15 may have resulted from cows that received BMRCS during the transition period being in a more positive nutrient balance than cows fed CCS. The results of this study indicate the importance that digestible NDF can have in transition diets and the long-term production responses that can occur when intake is increased in the transition period. © 2012 American Dairy Science Association. Source

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