|MARFO-AHENKORA, E - Crop Research Institute - Ghana|
Submitted to: Extension Publications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/28/2013
Publication Date: 2/8/2014
Citation: Marfo-Ahenkora, E., Aiken, G.E., Flythe, M.D. 2014. Fermentation characteristics and nutritive value of low moisture silage made from mature bermudagrass (C. dactylon) and switchgrass (P. virgatum) in mixture with alfalfa (M. sativa) or treated with urea and plantain (Musa AAB). Ghana Journal of Agricultural Science. 47(1):15-29.
Interpretive Summary: Silage making is practiced widely in intensive animal production systems in temperate regions, principally for winter feeding and to provide high quality conserved feed all year. Ensiling could be the most suitable method of preserving forage in the tropics because it is independent of weather conditions. Silage preparation could be one of the solutions for addressing the scarcity of good quality forage due to the severe and long dry season experienced in parts of the tropics; however, tropical grasses could lack the protein and energy concentrations to generate sufficient fermentation. Methods of improving silage quality are to add protein-rich legume in mixture with the tropical grass, or to treat the silage with urea and/or plantain. An experiment was conducted to determine the effect of different percentages of alfalfa in mixture with bermudagrass and switchgrass on nutritive value and fermentation characteristics. Inclusion of 25% alfalfa provided the highest glucose and lactate for both bermudagrass and switchgrass, but the overall quality of the switchgrass silage was better than that of bermudagrass silage. Protein and lactate of silage made with warm-season perennial grasses can be increased with an addition of a high-protein legume to provide 25% of the fresh weight. Bermudagrass silages were generally low in quality except for when the silage was treated with plantain alone. The lactate contents of the bermudagrass were generally lower than that of the switchgrass in the second experiment. The silage quality of switchgrass could be improved with addition of 25-50% alfalfa or addition of urea (6 g or 12 g) in combination with plantain (200 g or 400 g) / kg of grass. The use of plantain alone as an additive can improve silage quality of bermudagrass. This management practice could benefit livestock producers in tropical Africa who must preserve low-quality perennial grasses for feeding livestock during their dry seasons when forage production can be extremely low.
Technical Abstract: Two experiments were conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silages and also to investigate the effect of plantain and or urea as additives in switchgrass and bermudagrass silages using mini-silos of dimension 10.16 cm x 35.56 cm (4 x 14 inches) PVC pipes with rubber caps on each end. In the first experiment switchgrass and bermudagrass were ensiled separately in combination with four percentages of alfalfa (0%, 25%, 50% and 75%) on fresh weight basis. In the second experiment, switchgrass and bermudagrass were ensiled with or without urea (6 g or 12 g per kg fresh weight of grass) and or plantain (200 g or 400 g per kg fresh weight of grass) as additives. The alfalfa or additives were thoroughly mixed with the grasses and put in the micro-laboratory silos. Three replicates of the mini-silos were used for each treatment. Following 30-day fermentation, the laboratory silos were opened and sampled. Percentages of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), and in vitro dry matter digestibility (IVDMD) were determined. Fermentation characteristics of the silages such as pH, lactate, acetate, butyrate, glucose, and ethanol were also determined. The results indicated that increased alfalfa percentages in the mixture resulted in increased, CP, digestibility and fibre of the switchgrass silage. The 25% alfalfa inclusion for switchgrass, had significantly (P= 0.05) higher values for lactate contents compared to the other treatments. The 50% alfalfa inclusion for switchgrass had the lowest pH (4.6). As alfalfa percentages increased from 0% to 75%, lactate content of bermudagrass silages was reduced from 5.4 to 1.6 mM. The lactate content was significantly (P= 0.05) higher for bermudagrass silage with 0% and 25% alfalfa. Bermudagrass silages were generally low in quality (most pH above 5).The lactate contents of the bermudagrass were generally lower than that of the switchgrass in the second experiment. The urea + plantain combinations resulted in the highest lactate values and lowest pH values (4.2-4.4) for switchgrass. Switchgrass silage benefitted most from addition of alfalfa, urea and plantain. The silage quality of switchgrass could be improved with addition of 25-50% alfalfa or addition of urea (6g or 12g) in combination with plantain (200 g or 400 g) / kg of grass. The use of plantain alone as an additive can improve silage quality of bermudagrass and a legume can be mixed with switchgrass to enhance silage quality.