Elephant grass is one of the most important fodder grasses for ruminants in the tropics, largely due to its high productivity (Moran, 2011). It is grazed, used for cut-an-carry, dried or ensiled. The high variability among cultivars may result in many differences regarding intake and animal performance (Islam et al., 2003). There is a trade-off between nutritive value, which decreases with the maturity of the plant, and the forage production, which depends on rainfall (Machado et al., 2008).
Palatability
Elephant grass is extremely palatable when young and leafy (Cook et al., 2005). However, it becomes coarse and unpalatable when it matures. In a trial in Nigeria, fresh elephant grass cut during the dry season was less palatable to West African dairy goats than Guinea grass (Megathyrsus maximus), Gliricidia sepium, Leucaena leucocephala or Terminalia catappa. Goats were also found to refuse elephant grass in a free-grazing trial (Babayemi, 2007). Animals tend to select the most palatable and nutritive parts so that differences in quality are less important in the actual intake than in the offered feed, as was shown in a trial in Venezuela with sheep fed ad libitum elephant grass cut at different stages (Butterworth, 1965). For that reason, fresh elephant grass is often chopped to prevent animals from selecting the best parts (Moran, 2011).
Digestibility and intake
Elephant grass is rather low in energy and protein, due to its high cell wall content (Artus-Poliakoff et al., 1991; Krishnamoorthy et al., 1995). Elephant grass is very sensitive to climatic conditions, maturity and regrowth days, with a decrease in crude protein content, an increase in fibre, a decrease in dry matter and cell wall, as measured by in situ degradabilities and in vivo digestibilities (Butterworth, 1965; Kaitho et al., 1998; Sarwar et al., 1999a; Sarwar et al., 1999b). As in most grasses, young grass has a better nutritional value. However, because its cell wall content does not increase with age as fast as in other tropical forages, such as kikuyu (Pennisetum clandestinum) and pangola grass (Digitaria eriantha), elephant grass retains a given level of digestibility for a longer period (Orodho, 2006). In Venezuela, OM digestibility measured on sheep ranged from 65% at 30 days of regrowth to 60% at 70 days (Butterworth, 1965). In Brazil, DM intake and OM digestibility measured in steers linearly decreased with days of regrowth: OM digestibility varied from 75% at 33 days to 56% at 93 days. The authors recommended using of elephant grass between 30 and 35 days of regrowth (Machado et al., 2008).
A comparison of grass species in Brazil found that elephant grass has an in vitro DM digestibility similar to signal grass (Brachiaria decumbens), but higher than Guinea grass (Megathyrsus maximus) with a lower insoluble potentially degradable fraction and a higher degradation rate for DM, crude protein and cell wall (Benedetti et al., 2008). Elephant grass harvested in Central Brazil during the dry season after 100 days of growth had a better nutritive value (gas production) than Bermuda grass (Cynodon dactylon), giant star grass (Cynodon plectostachyus) and koronivia grass (Brachiaria humidicola) due to its lower cell wall and lignin contents, and higher N content (Nogueira Filho et al., 2000).
When elephant grass is very young, its high water content might decrease voluntary intake due to a fill effect caused by water intake (Soares et al., 2009). Some results suggest that, at restricted level of intake, maturity can result in an increase of metabolizable energy available in the gastrointestinal tract (Kozloski et al., 2003). The duration of rumination and the transit time of feeds increased markedly with older grass, resulting in an increased digestive efficiency (Butterworth, 1965). In Pakistan, the use of N fertilizer increased the protein concentration of the elephant grass but could not reverse the adverse effects of maturity on nutrient digestibility in buffaloes (Sarwar et al., 1999a; Sarwar et al., 1999b).
Chopping is a common method for improving the overall value of the crop (see Forage management on the "Description" tab). Further processing with a roller mill may increase forage intake due to the higher rate of rumen digestion of the fibrous material through a greater cell wall surface area available for digestion by rumen microbes. Increasing forage intakes will reduce total feed costs, and improve feed efficiency and hence farm profits (Moran, 2011).
Fresh forage
Dairy cattle
Elephant grass is a popular forage in smallholder dairy farms in the tropics, where it is considered as an ideal crop. It is often used for cut-and-carry as it can be easily harvested by hand for feeding to the stalled animals (Moran, 2011). In Kenya, it was suggested that elephant grass should be fed to dairy cows when it reaches a height of 55-60 cm (7-8 weeks) and 130-140 cm (9-10 weeks) in the medium and high rainfall areas (Muia et al., 1999). However, its low DM and high fibre content, as well as the physical nature of the crop, reduces the utilisation of freshly harvested elephant grass (Moran, 2011). As a sole feed or when supplemented only with leucaena, elephant grass will only support milk yields of 7 to 8 litres/cow/day (Muia et al., 2000b). Grass height (1 m vs. 1.5 m, i.e 4 to 6 weeks vs. more than 6 weeks) significantly affected daily DM intake (9.3 and 6.8 kg), total daily DM intake (10.5 and 7.9 kg), daily live-weight losses (165 and 490 g) and daily milk yield (8.6 and 6.9 kg/d, respectively) by cows fed ad libitum for 14 weeks from week 3 of lactation (Muinga et al., 1992).
Generally, a basal diet of elephant grass should be supplemented with a legume forage or with by-products to achieve adequate dairy performance.
Table 2. Effect of supplementation on performance of dairy cattle fed a basal diet of elephant grass:
| Country |
Animals |
Diet |
Results |
Reference |
| Brazil |
Holstein and crossbred (Holstein × Jersey) mid-lactation cows,
20 kg/d |
Elephant grass pasture + concentrate (8.7% protein) |
Met protein requirements, highest efficiency of nitrogen utilisation. |
Danes et al., 2013 |
| Brazil |
Lactating Holstein × Zebu cows |
Elephant grass pasture + chopped sugarcane with 1% urea |
Minimized the effects of the low pasture intake during the dry season. |
Lopes et al., 2004 |
| Kenya |
Mid-lactation Jersey cows |
Elephant grass pasture + 3 kg maize bran + 8 kg fresh Clitoria ternatea or Mucuna pruriens or Gliricidia sepium |
Similar dairy performance for all legumes. |
Juma et al., 2006. |
| Kenya |
Ayrshire/Brown Swiss × Sahiwal cows |
Elephant grass ad libitum + 0, 4 or 8 kg fresh Leucaena leucocephala |
Increased daily DM intake, reduced daily liveweight loss and increased daily milk yield (7.3, 7.7 and 8.3 kg, respectively). |
Muinga et al., 1992 |
| Kenya |
Ayrshire/Brown Swiss × Sahiwal cows |
Elephant grass ad libitum + 1 or 2 kg leucaena or 2 kg leucaeana + 1 kg maize bran |
Supplementation with maize bran and leucaena increased DM intake and allowed a higher milk yield than elephant grass alone or supplemented with leucaena. Maize bran increased energy utilization. |
Muinga et al., 1995 |
| Kenya |
Dutch Friesian cows |
Mature elephant grass ad libitum + 3.65 kg DM sunflower meal or sun-dried poultry litter |
Increased milk production but cows fed 2 months or 15 weeks elephant grass lost weight. Supplementation with sun-dried poultry litter is suitable for low to medium producing cows whereas supplementation with sunflower meal is to be preferred for high production. |
Muia et al., 2000a; Muia et al., 2001 |
| Tanzania |
Crossbred dairy cows (Bos taurus x Bos indicus) 400 kg,
9 kg/d milk |
Elephant grass ad libitum + Gliricidia sepium + cottonseed meal |
1.6 kg/d of cottonseed meal gave the highest milk yield but the best economic return was obtained with 0.5 kg/d DM cottonseed meal and 1.3 kg/d DM Gliricidia. |
Shem et al., 2003. |
Growing cattle
Elephant grass forage is able to support high animal production in tropical environments. In Hawaii, live-weight gains as high as 549 kg/ha were obtained with beef cattle grazing mature elephant grass (FAO, 2015). Live-weight gains of 1 kg/hd/day during the growing season and 480 kg/ha/yr are achievable (Cook et al., 2005). However, supplementation has a positive effect on performance, particularly with animals fed mature grass.
Table 3. Effect of supplementation on growth performance of growing cattle fed a basal diet of elephant grass:
| Country |
Animals |
Diet |
Results |
Reference |
| Kenya |
Growing Friesian heifers |
Fresh elephant grass (0.5 m, 6 weeks growth) ad libitum |
Average daily gain 0.5 kg/d, similar to that obtained with fresh sweet potato vines, but lower than with alfalfa hay (0.68 kg/d). |
Kariuki et al., 1998 |
| Kenya |
Growing Friesian and Sahiwal heifers |
Fresh elephant grass (0.5 m, 6 weeks growth) ad libitum alone or with fresh Desmodium intortum (intercropped) or with Desmodium hay or alfalfa hay |
Average daily gains were 0.41, 0.45, 0.52 and 0.42 kg/d respectively but the diet with intercropped Desmodium gave the best economic returns. |
Kariuki et al., 1999a; Snijders et al., 2011 |
| Kenya |
Growing Friesian and Sahiwal heifers |
Fresh elephant grass (6 or 12 weeks growth) ad libitum alone or with alfalfa hay (1.5-3.5 kg) |
Supplementation increased DM intake and average daily gain, from 0.32 kg/d to 0.65 kg/d in the case of 12-week grass. |
Kariuki et al., 1999b |
| Kenya |
Growing Friesian heifers |
Fresh young elephant grass (7 weeks growth) ad libitum alone or old elephant grass (16 weeks) + 25% fresh Desmodium intortum (intercropped), Calliandra calothyrsus or Sesbania sesban |
Average daily gain of 1.0 kg/d with young elephant grass. Old elephant grass supplemented with Desmodium, Calliandra and Sesbania allowed adequate daily gains of 0.64, 0.73 and 0.61 kg/d respectively. |
Kaitho et al., 1998 |
| Kenya |
Growing Friesian steers |
Fresh elephant grass (8 weeks growth) ad libitum alone or + 10-30% (DM) of fresh Desmodium intortum or sweet potato vines |
Supplementation increased OM and protein intake, DM degradation and rumen fermentable OM. |
Kariuki et al., 2001 |
| Brazil |
Charolais, Nellore and crossbreed steers and heifer calves |
Elephant grass pasture + concentrate at 0.5, 0.75, 1.0 and 1.25% of body weight |
Liveweight gain increased with the level of supplementation from 0.56 to 0.85 kg/d. |
Neumann et al., 2005 |
Sheep and goats
Sheep and goats raised for meat or milk can be fed fresh elephant grass, usually in zero-grazing systems. Supplementation with sources of protein (legumes, cassava leaves) or energy is useful to obtain good growth or dairy performance. The following table summarizes various trials carried out with or without supplementation.
Table 4. Performance of small ruminants fed a basal diet of elephant grass with or without supplementation:
| Country |
Animals |
Diet |
Results |
Reference |
| Indonesia |
Javanese Thin-tail lambs and crossbred kids |
Elephant grass ad libitum + up to 50% (DM) cassava-urea |
Maximal average daily gain, feed efficiency and carcass weight at 30% cassava for sheep and 40% for goats. |
Van Eys et al., 1987 |
| Indonesia |
Javanese Thin-tail lambs and Kacang kids |
Elephant grass + tree legume foliage or wilted cassava leaves |
Increased average daily gain up to 50 g/d for lambs and 20 g/d for kids. Faster gains were obtained with higher intakes of tree legume foliage, or with combinations of higher-energy supplements such as rice bran, cassava meal and molasses. |
Johnson et al., 1989 |
| Mexico |
Pelibuey male lambs |
Elephant grass ad libitum alone + 20 or 30% (DM) duckweeds (Lemna sp. and Spirodela sp.) |
Improved nutrient digestibility, nitrogen retention and rumen ammonia concentration. |
Zetina-Cordoba et al., 2013 |
| India |
Sikkim goats (meat) |
Elephant grass ad libitum |
Elephant grass fed alone could support the energy requirements of meat goats at maintenance. |
Chandra et al., 2012 |
| Kenya |
Kenya Dual-Purpose male goats |
Elephant grass + pasture grass + Neonotonia wightii or Leucaena leucocephala (30% requirement) |
Increased average daily gain, particularly with leucaena. |
Njarui et al., 2003 |
| Uganda |
3-4 months kids |
Elephant grass ad libitum + 300 g of either gliricidia or gliricidia with leucaena or gliricidia + leucaena + maize bran |
Increased average daily gain. |
Mpairwe et al., 2002 |
| Kenya |
6 months old East African goats |
Elephant grass ad libitum + sun dried leaves of Pithecellobium dulce (22.5 g DM/kg LW0.75) |
Increased DM intake, OM digestibility, N retention and average daily gain. |
Kahindi et al., 2007 |
| Malaysia |
Growing Boer x local female goats |
Elephant grass ad libitum + molasses, palm kernel meal and soybean waste or + commercial concentrate (1% liveweight) |
Higher growth performance with palm kernel supplementation than with commercial concentrate. |
Rahman et al., 2013 |
| Kenya |
Lactating Toggenburg dairy goats |
Elephant grass (7 weeks growth) ad libitum |
Elephant grass fed alone could support the energy requirements of dry and pregnant goats, but not of lactating goats even if they are able to choose the most nutritive parts. |
Brown et al., 1988 |
Hay
Elephant grass can be used as hay, though this is less common.
Buffaloes
In Egypt, lactating buffaloes received elephant grass hay replacing 37% of a diet (55% concentrate, 30% clover hay, 15% rice straw, DM basis). There was no effect on milk and milk fat yields, though milk fat content was slightly changed, and milk protein and solid not fat (SNF) content increased. However, 66% substitution decreased yields, solid non fat and milk protein. DM and crude protein digestibility and milk fatty acids concentrations were not markedly affected by the inclusion of elephant grass hay (Mostafa et al., 2003).
Sheep
In Brazil, with lambs fed dwarf elephant grass hay cut at 30, 50, 70 and 90 days of regrowth, aging resulted in a decrease in NDF intake and DM, OM and NDF digestibility. Aging did not influence DM and OM intake, the flow of rumen microbial N into the small intestine, and efficiency of rumen microbial protein synthesis. Nitrogen intake was minimum at 70 days while N digestibility and retention were maximum at the same age (Kozloski et al., 2005). In another trial with lambs, elephant grass hay had a higher forage quality than bahia grass (Paspalum notatum) hay due to its higher voluntary intake of digestible OM. Sheep chewed elephant grass hay at a greater rate than bahia grass hay and spent less time ruminating, due to its less fibrous leaf structure and more readily digested leaf epidermis (Flores et al., 1993). In feedlot sheep, elephant grass supplemented with 30% concentrate allowed an average daily gain of 95 g/d, comparable to that obtained with buffel grass (Cenchrus ciliaris), Panicum molle and Urochloa mosambicensis (Camurca et al., 2002).
Goats
In Brazil, chopped elephant grass hay (60 d regrowth) fed to goats resulted in DM intake and OM digestibility (61%) comparable to those obtained with pearl millet (Pennisetum glaucum) and Sudan grass (Sorghum × drummondii) hays, and higher than those obtained with forage sorghum hays (Aguiar et al., 2006a). With growing goats fed a concentrate and elephant grass hay, the inclusion of 60% and 45% hay resulted in the best cost/benefit ratio for male and female goats, respectively (Medeiros et al., 2007).
Silage
Nutritive value of elephant grass silage is dependent on the forage value at ensiling and is lower when old grass is used, compared to younger material (Yokota et al., 1994). It is often preferable to ensile elephant grass with a source of carbohydrates such as molasses or sugarcane that improves silage quality and its nutritional value. See the section on Forage management on the "Description" tab for examples of silage ingredients and their benefits.
