Rice bean fodder (fresh, hay and straw) and rice bean seeds can be fed to ruminants.
Rice bean forage at the pre-flowering stage is palatable to sheep (Chandel et al., 1988). In Nepal, farmers have emphasized the softness and palatability of rice bean fodder for livestock (Joshi et al., 2008). In an experiment with rice bean hay in India, bullocks consumed it hesitantly at first, but within a few days the animals grew accustomed to it and DM consumption increased, indicating that the hay was palatable (Gupta et al., 1981). Rice bean straw was reported to be relished by cattle (Göhl, 1982).
Fresh rice bean forage
In India, 22 month-old calves fed a mixture of fresh Sudan grass (Sorghum × drummondii) and rice bean forage (54:46 fresh basis) for 64 days had a DM intake of 1.90 kg DM/100 kg LW and a daily weight gain of 456 g/d (Singh et al., 2000). In India, 22 month-old calves fed a mixture of fresh Sudan grass (Sorghum × drummondii) and rice bean forage (54:46 fresh basis) for 64 days had a DM intake of 1.90 kg DM/100 kg LW and a daily weight gain of 456 g/d (Singh et al., 2000).
Rice bean hay
Rice bean hay is generally used as a protein source to supplement poor quality roughage-based diets in ruminants.
In Thailand, rice bean hay supplementing a Congo grass (Brachiaria ruziziensis)-based dairy cow diet increased milk yield and decreased feed cost, resulting in higher farmer income. Rice bean hay supplementation did not alter rumen volatile fatty acid (VFA) production, or increase diet digestibility and intake (Wanapat et al., 2012).
In India, a trial with bulls showed that rice bean hay had a moderate OM digestibility (50%) but that it contained nitrogen, calcium and phosphorus in adequate amounts to meet the maintenance needs of adult cattle (Gupta et al., 1981). In Vietnam, a mixture of cassava hay and rice bean hay (3:1 ratio) replaced 60% of concentrate in a forage-based diet (Pennisetum purpureum + urea-treated rice straw) offered to growing crossbred heifers, resulting in higher daily weight gain (609 g/d), better feed efficiency and reduced feed costs (Thang et al., 2008).
In Thailand, rice bean hay included at 600 g/d to supplement rice straw in diets for swamp buffalo increased DM intake, digestible protein and N retention. It had a positive effect on rumen microflora, resulting in increased VFA production and lower CH4 emissions (Chanthakhoun et al., 2011). Adding rice bean hay was reported to increase cellulolytic rumen bacteria, thus improving the utilization of high fibrous feeds in buffalo diets (Chanthakhoun et al., 2010).
In India, supplementing local goats fed grass with rice bean hay (15% of diet DM) did not increase grass intake, but total DM intake and nutrient digestibility were increased. Increasing the level of rice bean level above 15% had no further effect on digestibility (Das, 2002).
Rice bean straw
In India, a trial with bullocks showed that rice bean straw had a low OM digestibility (31-47%) and it was recommended to supplement a rice straw-based diet with energy-rich feed materials, such as cereal grains or bran (Chaudhuri et al., 1981).
Rice bean seeds
In India, rice bean seeds are fed to buffalo calves and sheep to provide energy. Rice beans replaced half the cereals and half the deoiled cake present in the concentrate offered to buffalo calves (Ahuja et al., 2001). In sheep, replacing 50% of the metabolizable energy from oat hay by rice bean seeds had no deleterious effect on sheep N balance, which remained positive (Krishna et al., 1989).