Leucaena leucocephala has been being recognized as a high-potential fodder for centuries. Its nutritional value is comparable with that of alfalfa with a high ß-carotene content (Ecoport, 2009). The content in condensed tannins (2.6% DM) in the leaves and stems reduce DM digestibility but enhances by-pass protein (FAO, 2009; Cook et al., 2005).
Leucaena leucocephala can survive for decades under heavy cutting or grazing. It provides high quality forage during the dry season and is very palatable to cattle, sheep and goats (Jones, 1979). Moreover, it grows well in association with many subtropical and tropical grasses (Cook et al., 2005).
Cattle
When leucaena pasture is used as a supplement during the dry or winter season, it substantially improves live-weight gain compared to pure grass pasture, particularly if the pasture is of low quality (Jones, 1979). When the diet contains large amounts of Leucaena leucacephala, without the detrimental effects of mimosine, animals performed better than on pure pasture or grass/legume pasture (twice that of grass/siratro in the same soil conditions). Live-weight gains ranged from 0.36 kg/head/day (over a 315-day period) to 1.1 kg/head/day (over a 90-day period). When cattle were able to detoxify DHP, live-weight gains were even higher (1,442 kg/ha/year = 0.64 kg/head/day) (Shelton et al., 1998).
Feeding dairy cows on cut-and-carry leucaena foliage increased milk production by 14% and also increased milk fat and protein contents. Dairy cows grazing Brachiaria decumbens/Leucaena leucocephala produced higher milk yield than cows fed on the grass only cut-and-carry system. Cows fed Leucaena leucocephala ate less concentrate and did not need feeding on heavy fertilized grasses. They also gained more weight. However, diets containing high amounts of leucaena foliage are detrimental to reproduction in heifers or cows when the rumen is not inoculated with DHP-degrading bacteria: stillborn calves are numerous, calving percentage is reduced (66% vs. 88%), and calf weight at birth is lower. It is recommended that heifers be inoculated before pregnancy or given limited access to leucaena during early pregnancy (Jones, 1998).
Sheep
Leucaena is very palatable to sheep. Grazing sheep or sheep fed on grass hay have higher performances when they are supplemented with 25-50% of dried leucaena leaves (Osakwe et al., 2006; Tomkins et al., 1991). Larger amounts can be fed in periods of feed scarcity (Osakwe et al., 2006; Souza et al., 1999). Leucaena leaf meal or fresh leaves can also replace concentrate or ammoniated rice straw since it increases DM intake, protein intake and N retention, thus improving growth rate (Espinoza et al., 2005; Orden et al., 2000). Lambs fed leucaena leaf meal have a higher survival rate and growth rate (Reynolds et al., 1987). In spite of the mimosine content, reproductive performance is not altered by dry or fresh leucaena forage in rams (Nsahlai et al., 2005; Negussie Dana et al., 2000). Ewes fed leucaena hay had a good body weight at mating with higher ovulation rates (Selaive-Villarroel et al., 2002). Rumen inoculation with DHP-degrading bacteria is effective in sheep and results in satisfactory haematological parameters and growth performance (Mishra et al., 2002). Leucaena may reduce the cost of parasitic control (Medina et al., 2006).
Goats
Leucaena foliage is a very promising feedstuff for goats when compared to other legumes such as alfalfa, Lablab purpureus and Gliricidia sepium. It is rich in nutrients, resulting in better DM intake, weight gain and reproductive performance (Kanani et al., 2006; Babayemi et al., 2006; Pamo et al., 2004; Akingbade et al., 2004). Between 50 and 75% of leucaena foliage can be included in a grass-based diet (Aregheore et al., 2004; Odeyinka, 2001) and 30% when it replaces concentrate (Dutta et al., 2002), without affecting growth and milk production (Clavero et al., 2003). Fresh or wilted leucaena gives better DM intake, growth rate and N utilization than dried leucaena leaves (Aregheore, 2002).
Adding iodine to leucaena can alleviate the detrimental effects of mimosine in goats (Rajendran et al., 2001; Pattanaik et al., 2007). It is also possible for goats to become used to mimosine, resulting in increased weight gains and milk production (Kumar et al., 1998). Rumen inoculation with DHP-degrading bacteria is possible in female and male goats. Bucks transinoculated and fed leucaena have good quality semen (Akingbade et al., 2001; Akingbade et al., 2002).
Leucaena leaf meal included at 45% of the diet to supplement natural pastures increased crude protein intake, weight gain and fibre growth in Angora goats (Rubanza et al., 2007; Yami et al., 2000).
