PREDICTORS OF ALFALFA FORAGE QUALITY
C. Găvan, C. Bora, V. Motorga
The aim of this study was to use acid detergent fibre (ADF) and neutral detergent fibre (NDF) content, height and maturity stage of pre cut alfalfa as predictors of forage quality. Stands of pure first pre cut alfalfa, were sampled from various field experiments during May and June 2011 and 2012 at Agricultural Research and Development Station Simnic Craiova Romania. The samplings and measurements were repeatedly realized from the late vegetative to full flower stage in a 30x30 cm square. The alfalfa maturity stages were used to assign a numerical value to the most mature stem in the sample area. All samples were oven-dried at 60°C, homogenised to a particle size of 1 mm and analysed for dry matter (DM), ADF and NDF content. Digestible DM calculated from percent ADF, is on estimate of the digestibility of the feed. Dry matter intake, calculated from percent NDF is on estimate of the amount of feed on animal will consume in percent of body weight. Relative feed value (RFV) reflects both digestibility (from % ADF) and intake potential (from % NDF) of alfalfa forage. The plant height and maturity provides a close estimate of RFV in the field. By determining the RFV of standing alfalfa, producers can more accurately when to make first spring cut of alfalfa. Adapting of predictors method by growers can be facilitated by the development of simple tables.
Key words: alfalfa, acid detergent fibre, neutral detergent fibre, relative feed value