Sunday, February 1, 2009

Five Warm-Season Legumes as Supplemental Summer Forage for Meat Goats.

Susan E. Henderson1, Robert Lane1, and Craig Henderson2. (1) Agricultural and Industrial Sciences, Sam Houston State University, Huntsville, TX 77341-2088, (2) Psychology and Philosophy, Sam Houston State University, Huntsville, TX 77341-2088

In this study we analyzed goat preference, dry biomass yield (DM) and quality parameters for five legumes that have performed well in the humid East Texas region: ‘Iron and Clay' cowpea (Vigna unguiculata [L.] Walp.), ‘Rongai' lablab (Lablab purpureus [L.] Sweet), ‘Rio Verde' lablab, ‘Big Boy' soybean (Glycine max [L.] Merr.) and alyceclover (Alysicarpus vaginalis [L.] DC.).  Non-irrigated field plots measuring 5m x 21m were planted on May 23, 2008 in a randomized block design with three replicates of each legume. Subplot harvest for DM and qualitative factors was conducted 46 days after planting (DAP).  Animal selectivity of each legume was determined 49 DAP. The goats used in this study showed a significant preference toward alyceclover compared to the other legumes.  Alyceclover had a significantly greater leaf:stem ratio than soybean, cowpea and ‘Rio Verde' lablab.  However, due to limited rainfall (.15 cm) during establishment and the need to plant the small-seeded alyceclover at a shallow depth, alyceclover's coverage was considerably less than the other legumes and it produced less dry matter than all but soybean.  Cowpea produced the highest dry matter yield (2,707 kg ha-1), followed by ‘Rio Verde' lablab (2,122 kg ha-1), ‘Rongai' lablab (1,693 kg ha-1), soybean (627 kg ha-1) and alyceclover (330 kg ha-1).  While crude protein (CP) was similar for all legumes, acid detergent fiber (ADF) and neutral detergent fiber (NDF) were significantly higher in cowpea than all other legumes. Cowpea was also significantly higher than alyceclover and soybean in acid detergent lignin (ADL). Alyceclover was lower in ADF, NDF and ADL than cowpea and ‘Rongai' lablab and significantly lower in ADF than soybean. A negative relationship exists between bite rate and ADF and ADL, with alyceclover having the highest bite rate and lowest ADF and ADL.