|BARNEY ET AL., P|
Submitted to: American Society of Agronomy Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/24/2001
Publication Date: N/A
Technical Abstract: Soybeans (Glycine max) as a forage crop are a viable alternative to other legume forages in the crop rotation and diet of dairy cows. Research in Vermont, New York, and New Hampshire has been conducted since 1998 to study the feasibility of soybean varieties to be harvested and fed to dairy cows as forage. Maturity group I, III, and V, grain and forage varieties of soybeans were planted in 7", 12", and 30" row spacings, at varying populations. Methods of planting, harvesting, and storage were monitored. Yields, plant height, nodulation, number of pods, number of beans per pod, stage of maturity, and forage quality were measured at harvest. Feeding was monitored to dairy cows, on three farms, for impact on milk production, butterfat, and protein. Results showed a yield range of 1.16 ton to 4.5 ton of dry matter (DM) per acre with an average of 3.5 ton. Wet chemistry forage quality analysis on a DM basis showed a Crude Protein range of 13% to 25% with a mean of 20%. Acid Detergent Fiber range was 29% to 38% with the majority of samples between 30% and 35%. Neutral Detergent Fiber range was 31% to 45% with a mean of 39%. In vitro digestibilities ranged from 71% to 85% with a mean of 78%. A 2 lb to 4 lb/cow/day increase in milk production and an increase of .1 to .4 in Butterfat % was common, while milk protein stayed the same. Soybean yields, quality, milk production and quality during feedout, appear to match or exceed other legume forages in the diet of dairy cows.