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Elephant grass, merker grass, Napier grass, napier, Uganda grass, bana grass, barner grass [English]; herbe à éléphant, fausse canne à sucre, canne fourragère [French]; capim-elefante, capim-napiê [Portuguese]; pasto elefante, yerba elefante, zacate elefante, hierba elefante, gigante, pasto de Uganda [Spanish]; mfufu [Afrikaans]; erepani [Cook Island]; Olifantsgras [Dutch]; rumput gajah [Indonesian, Malaysian]; erba elefante, erba Napier, erba ugandese [Italian]; urubingo [Kinyarwanda]; mabingobingo [Kiswahili]; acfucsracsracsr [Kosraean]; senjele [Nyanja]; bokso [Palauan]; puk soh [Pohnpeian]; vao povi [Samoan]; buntot-pusa [Tagalog]; cỏ voi [Vietnamese]; الثيوم الأرجواني [Arabic]; 象草 [Chinese]; Слоно́вая трава́ [Russian]
The taxon Cenchrus purpureus (Schumach.) Morrone was proposed in 2010 as a replacement for Pennisetum purpureum Schumach. (Chemisquy et al., 2010).
Pennisetum benthamii Steud., Cenchrus purpureus (Schumach.) Morrone
Elephant grass (Pennisetum purpureum Schumach.) is a major tropical grass. It is one of the highest yielding tropical grasses. It is a very versatile species that can be grown under a wide range of conditions and systems: dry or wet conditions, smallholder or larger scale agriculture. It is a valuable forage and very popular throughout the tropics, notably in cut-and-carry systems (Mannetje, 1992; FAO, 2015).
Morphology
Elephant grass is a robust, rhizomatous, tufted perennial grass. It has a vigourous root system, developing from the nodes of its creeping stolons. The culms are coarse, perennial, and may be up to 4-7 m in height, branched above. Elephant grass forms dense thick clumps, up to 1 m across. The leaves are flat, linear, hairy at the base, up to 100-120 cm long and 1-5 cm wide, with a bluish-green colour. The leaf margin is finely toothed and the leaf blade has a prominent midrib. The inflorescence is a stiff terminal bristly spike, up to 15-20 cm in length, yellow-brown to purplish in colour. Spikelets are arranged around a hairy axis, and fall at maturity. Spikelets are 4-6 mm long and surrounded by 2 cm long plumose bristles. There is little or no seed formation. When seeds are present they are very small (3 million seeds/kg) (CABI, 2014; Francis, 2004; Mannetje, 1992; Duke, 1983). Elephant grass is very similar in appearance to sugarcane (Saccharum officinarum) but its leaves are narrower and its stems are taller (DAFF, 2014).
Utilisation
Elephant grass is a very important forage in the tropics due to its high productivity. It is particularly suited to feed cattle and buffaloes. Elephant grass is mainly used in cut-and-carry systems ("zero grazing") and fed in stalls, or made into silage or hay. Elephant grass can be grazed, provided it can be kept at the lush vegetative stage: livestock tend to feed only the younger leaves (FAO, 2015). Elephant grass, as implied by its name, is an important source of forage for elephants in Africa (Tchamba et al., 1993; Francis, 2004).
Elephant grass is a multipurpose plant. The young leaves and shoots are edible by humans and can be cooked to make soups and stews (Burkill, 1985). The culms can be used to make fences, and the whole plant is used for thatch. It is considered a potential second generation energy source crop in the USA (EPA, 2013). Leaf and culm infusions are reported to have diuretic properties (Duke, 1983). Elephant grass has several environmental applications. It can be used to make mulch and to provide soil erosion control. It is a weed controller and, in Africa, it has been reported to be used as a trap plant in push-pull management strategies to fight against stemborers in maize crops (see Environmental impact below) (Khan et al., 2007).
Many cultivars of elephant grass have been developed worldwide to suit local conditions and there is a wide range of habits, yield potential and nutritive value. "Merker" types have numerous relatively thin stems, narrow largely glabrous leaves, high yields, and are resistant to Helminthosporium. Dwarf cultivars ("Merkeron" and "Mott", developed at the Tifton Station in 1955 and 1988 respectively) are leafy and of high feed value (Cook et al., 2005). Elephant grass has the capability to exchange alleles with other Pennisetum species, and several hybrids have been developed. Hybrids of pearl millet (Pennisetum glaucum) and elephant grass ("King grass", "Pusa Giant", "Bana grass", "Florida" and others) benefit from the desirable characteristics of pearl millet such as vigour, drought resistance, disease tolerance, forage quality and seed size, whereas elephant grass provides rusticity, aggressiveness, perennity, palatability and high DM yield (Timbo et al., 2010).
Elephant grass originated from sub-Saharan tropical Africa (Clayton et al., 2013). It has been introduced as forage into most tropical and subtropical regions worldwide. It was introduced into the USA in 1913, in the 1950s into Central and South America and the West Indies, and in the 1960s into Australia. It is commonly naturalized and sometimes becomes invasive (CABI, 2014). Elephant grass in mainly found from 10 °N to 20 °S. It is often regarded as a weed in crops, along roadsides, waterways, wetlands, floodplain, swamps, forest edges, disturbed areas and wastelands (CABI, 2014; Francis, 2004). It can withstand drought conditions and is a pioneer species in arid lands such as the Galapagos Islands (CABI, 2014).
Elephant grass is a summer growing grass that grows from sea level up to an altitude of 2000 m (Francis, 2004). It does well in places where temperatures range from 25 °C to 40 °C (FAO, 2015) and where annual rainfall is over 1500 mm. It stops growing below 15 °C and is sensitive to frost, though it can regrow from the stolons if the soil is not frozen (Duke, 1983). Elephant grass is tolerant of drought and will grow in areas where the rainfall range is 200-4000 mm. Elephant grass is not tolerant of flooding and prefers well-drained soils. With poor drainage, it is best grown on raised beds (Göhl, 1982). It does better on rich, deep soils, such as friable loams, but can grow on poorly drained clays, with a fairly heavy texture, or excessively drained sandy soils with a pH ranging from 4.5 to 8.2 (FAO, 2015; Cook et al., 2005; Duke, 1983). Elephant grass is a full sunlight species that can still produce under partial shade but does not withstand complete shade under a dense tree canopy (Francis, 2004).
Establishment and yields
Elephant grass produces very few seeds and is mostly propagated vegetatively through stem cuttings consisting of at least 3 nodes, 2 of which are buried in rows. Row width ranges from 50 to 200 cm and distance within rows is between 50 and 100 cm (Mannetje, 1992). After planting, elephant grass grows vigorously and can reach 4 m in 3 months (Skerman et al., 1990). Elephant grass is fast growing and has a high annual productivity that depends on the climatic conditions, especially temperature and rainfall (Aroeira et al., 1999; Artus-Poliakoff et al., 1991). Elephant grass requires high levels of fertilizer and a regular water supply (Mannetje, 1992). Yields range from 20 to 80 t DM/ha/year under high fertilizer inputs (Francis, 2004; Skerman et al., 1990). With no, or inadequate, fertilizer, yields are in the range of 2-10 t DM/ha/year (Bogdan, 1977). Cuttings can be made at 45-90 day intervals, depending on location (FAO, 2015).
Association
Though elephant grass is mainly grown in pure stands, it can be cultivated in association with legumes such as puero (Pueraria phaseoloides), centro (Centrosema pubescens), perennial soybean (Neonotonia wightii) and leucaena (Leucaena leucocephala) (Mannetje, 1992). Such associations have higher nutritional value than elephant grass alone and can produce higher DM yields, suppress weeds and improve soil fertility. In central Kenya, a comparison of three legumes (Desmodium intortum, Macrotyloma axillare, Neonotonia wightii) associated with elephant grass concluded that Desmodium intortum was the best choice whereas Neonotonia wightii gave the lowest performance (Mwangi et al., 2004). Elephant grass is sometimes intercropped with banana and cassava in home gardens (Mannetje, 1992).
Fresh grass
The ideal harvest regime depends on the cultivar, weather conditions, soil fertility, management practices and livestock needs. In Kenya, the recommendation is to harvest elephant grass for the first time when it attains a height of 1-1.2 m, usually 3-4 months after planting. Thereafter the grass should be harvested at intervals of 6 to 8 weeks, at the same height. Well-managed elephant grass can be harvested every month in hot and wet environments, or every 2 months in drier areas. Harvesting at longer intervals produces higher DM yields but lower quality forage as protein and ash content, digestibility and leaf-to-stem ratios decline. Leaving 10-15 cm high stubble provides sufficient carbohydrate reserves for subsequent regrowth (Orodho, 2006).
Elephant grass is often fed fresh in cut-and-carry systems. It can be manually or mechanically chopped prior to feeding to reduce the selection of leaves and stems by the animal. Chopping and then wilting in the sun for several hours reduces moisture, stimulates appetite, facilitates rumination and thus improves forage utilisation (Moran, 2011).
Pasture
When used for pasture, elephant grass should be heavily grazed so that most of the young leaves and shoots, which have the highest nutritive value, are available to ruminants. Grazing at 6-9-week intervals at a height of about 90 cm gives good utilization. Nitrogen can be applied after each grazing or cutting in high-rainfall areas. Any coarse, leafless stems should be mowed (FAO, 2015).
Hay and dry grass
When elephant grass is intended for hay it should be cut at an early stage of maturity as the stems become too coarse when the plant ages. In Taiwan, elephant grass is used for the production of dehydrated grass pellets used as a supplementary stock feed (Manidool, personal communication cited by FAO, 2015).
Silage
Elephant grass can be processed into high quality silage and may be ensiled alone (FAO, 2015). However, its high cell wall content and low concentration in water soluble carbohydrates (WSC) impair the ensiling process. In Zimbabwe, it was concluded that elephant grass should be harvested for ensiling between 6 and 7 weeks, at the peak of WSC concentration, to increase DM content and optimize herbage production without affecting nutritive value. In practice, the high moisture of elephant grass when its nutritive value is highest is an obstacle for using it as silage, because it results in undesirable fermentation with considerable nutrient losses (Manyawu et al., 2003a). For these reasons, elephant grass is often ensiled with materials that improve the quality of the silage and its nutritional value (protein or energy). The following table lists materials cited in the literature.
Table 1. Materials used for ensiling elephant grass:
| Country | Material | Results | Reference |
| Japan | Molasses (4-5%) | Improved silage quality by increasing lactic acid content and reducing pH value, ammonia nitrogen and acetic, propionic and butyric acid contents. Molasses addition did not modify nutrient digestibility (goats) but inhibited proteolysis during the ensiling process, and improved nitrogen retention. Molasses increased WSC in the silage, increasing its value as an energy source. | Yokota et al., 1992; Yokota et al., 1991; Yunus et al., 2000 |
| Japan | Molasses (4%) and defatted rice bran (15%) | Improved fermentation quality and thus enhanced silage utilization. | Yokota et al., 1998 |
| Thailand | Molasses or cassava roots (5%) | Higher digestibilities with molasses than with cassava (cows). | Bureenok et al., 2012 |
| Brazil | Sugarcane (25%) | Sugarcane provided readily fermentable sugars while coarse mature elephant grass acted as an absorbent and provided high DM content. | Cavali et al., 2010 |
| Brazil | Sugarcane (30 to 45%) and cocoa meal (15%) | Increased the degradability of mature forage. | Teixeira et al., 2008 |
| Brazil | Cassava pomace (5%) | Increased non-fibrous carbohydrates, good preservation, good digestibility (dairy heifers). | Andrade et al., 2010; Silva et al., 2007 |
| Nigeria | Cassava peels (up to 50%) | Improved the physical attributes of the silage and its nutritive value (goats). | Olorunnisomo, 2011 |
| Zimbabwe | Pre-wilting with maize meal (5%) | Increased intake and palatability (sheep). | Manyawu et al., 2003b |
| Ethiopia | Dehydrated cashew stalks (16% fresh basis) | Increased nitrogen content. | Teles et al., 2010 |
| Brazil | Cashew or dehydrated pineapple by-products (10.5%) | Increased body weight gain (sheep) when compared with elephant grass silage alone. | Ferreira et al., 2009b |
| Brazil | Pineapple by-products (14%) | Increased digestible nutrient intake (sheep). | Ferreira et al., 2009a. |
| Japan | Phasey bean (Macroptilium lathyroides) (25%) | Improved the nutritive value of silage. | Yunus et al., 2001 |
| Brazil | Cocoa meal (10-30%) | Increased nitrogenous fractions, but also the non-digestible fraction of carbohydrates and acid detergent insoluble nitrogen, which limits the use of cocoa meal as a silage ingredient. | Andrade et al., 2010 |
| Brazil | Passion fruit by-product, dehydrated (14%) | Increased the energy value, intake and digestibility of the silage (sheep). | Neiva et al., 2006 |
| Brazil | Acerola (Malpighia emarginata) by-product dehydrated (14%) | No effect on DM intake and nutrient digestibility, but positive nitrogen balance (sheep). | Ferreira et al., 2010 |
Standover or deferred feed
In Queensland (Australia), elephant grass has been used for dry-season feed by rolling at the end of winter, as it can make some winter growth during this period (Quinlan et al., 1975).
Weed and soil erosion control
Elephant grass is a pioneer species that competes very efficiently with weeds (FAO, 2015; D'Antonio et al., 1992). In the Philippines, it has been used to control Imperata cylindrica (Skerman et al., 1990; Duke, 1983). In Nigeria, elephant grass has been used as mulch (25 cm layer) for weed control, for water storage and to reduce soil losses on slopes (Adekalu et al., 2007; Francis, 2004). Elephant grass develops a vigourous root system that may help to prevent river bank erosion. Planted as hedgerows, elephant grass makes fences and provides effective windbreaks for crops and houses. It is used for erosion control and forage production in alley-cropping systems of agroforestry (Magcale-Macandog et al., 1998).
Biological control agent of pests
Elephant grass in association with molasses grass (Melinis minutiflora) or Desmodium spp. may be a valuable biological agent to control the maize stemborer moth. The moth, pushed out of the field by molasses grass or Desmodium, lay eggs on elephant grass. When the larvae start boring elephant grass, the plant releases a sticky liquid that kills almost all larvae while the surviving ones are attacked by Cotesia sesamiae (Khan et al., 2007; Parrott, 2005).
Invasiveness
Elephant grass is considered a noxious weed in many places in the world (CABI, 2014). Its ability to out-compete other plants makes it very aggressive, particularly to communities of native plants. This has been reported in the Galapagos Islands (Mauchamp, 1997) and in Florida (Francis, 2004).
Methane production
Methane production by ruminants is linked to structural carbohydrates contained in forage-based diets. Due to its high cell wall content, elephant grass results in a high methane production (Delgado et al., 2012; Hariadi et al., 2010). The addition of 20-25% foliage of plants such as Acacia mangium, Biophytum petersianum, Jatropha curcas, Psidium guajava, Sapindus saponaria, Morus alba or Trichanthera gigantea to a basal diet of elephant grass significantly reduced in vitro methane production in comparison to elephant grass fed alone (Delgado et al., 2012; Hariadi et al., 2010).
Second generation energy crop
In the USA, the Environment Protection Agency agreed that elephant grass could be used as a source of biofuel under the Renewable Fuel Standard Program provided producers respect the Risk Management Plan for early detection and rapid response to potential spread (EPA, 2013).
Elephant grass has a rather low protein content (about 10% DM) but young grass can be very nutritive. In Venezuela, for instance, protein values ranged from 21% DM at 30 days of regrowth to less than 4% DM at 70 days (Butterworth, 1965). Elephant grass is rich in fibre: depending on stage of maturity, NDF concentrations vary from 55 to 75% DM (Moran, 2011). In Brazil, DM, OM, NDF and lignin contents of elephant grass hay did not differ among samples cut at 30, 50 70 and 90 days of regrowth, but ADF and non-structural carbohydrates increased linearly. Non-protein N accounted for almost all soluble N contents, which increased four-fold from 30 to 70 days and decreased at 90 days of regrowth (Kozloski et al., 2005). Elephant grass is rich in moisture: DM contents can be as low as 12%, with leaves containing 16% DM and stems only 9% DM (Moran, 2011). In Indonesia and Central Africa (Gabon and Cameroon), its nutritive value was lower in the dry season (less protein and more lignin) than in the rainy season (Evitayani et al., 2004a; Tedonkeng Pamo et al., 2007). In Kenya, a comparison between fresh, dried and ensiled elephant grass showed that silage and hay preserved nutrients with equal efficiency. Therefore, surplus wet season elephant grass could be preserved for use during dry seasons under tropical climate (Brown et al., 1985). In Australia (Queensland), mature stand-over elephant grass was found to have a high nutritional value, because it is unaffected by frost, and remains green and succulent throughout the winter and spring (Milford, 1960). In several countries (Indonesia, Philippines, Cameroon), phosphorus, magnesium, sulphur, copper, zinc and selenium contents of elephant grass were generally below the critical level to satisfy requirements of grazing livestock in the tropics, but calcium was sufficient (Nasrullah et al., 2004; Njwe et al., 1988; Orden et al., 1999).
Nitrate poisoning
Elephant grass can cause nitrate poisoning in cattle when used as the sole component of the diet (Cook et al., 2005). Fatal nitrate poisoning of cattle fed solely on elephant grass was reported in Malaysia in 1979. Nitrate levels in elephant grass from the toxic area averaged 28.3 mg/g (up to 44 mg in some samples) while level from non-toxic areas was 3.9 mg/g (Seiler et al., 1979). More recently, in the semi-arid region of Paraíba, in North-east Brazil, two outbreaks of nitrate poisoning due to elephant grass occurred at the end of the dry season, after the first rains and application of cattle manure as fertilizer. Clinical signs were anorexia, respiratory distress, teeth grinding, depression or hyperexcitability, tremors, abdominal contractions, salivation, nasal discharge, uncoordinated gait, cyanosis, and finally recumbency (Medeiros et al., 2003).
Oxalate content
Oxalate levels of 2.5-3.1% of DM have been reported but no problems were recorded (Cook et al., 2005).
Mature leaves
The mature leaves are razor sharp and can sometimes hurt grazing cattle (FAO, 2015).
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.
Elephant grass is commonly used as fresh forage for rabbit feeding in tropical countries such as Vietnam (Dinh Van Binh et al., 1991), Mozambique (Demeterova et al., 1991), Nigeria (Ekpenyong, 1984; Amata et al., 2013) and Venezuela (Nieves et al., 1996). Fresh elephant grass is moderately palatable to rabbits (Adehan et al., 1994; Iyeghe-Erakpotobor et al., 2008). However, palatability can be high during the rainy season when the protein content is high (17-18% DM) (Raharjo et al., 1986) and low during the dry season (McNitt, 1980; Muir et al., 1996).
Fresh elephant grass fed as the sole feed did not support growth and induced weight losses (Raharjo et al., 1986). However, fresh elephant grass fed with a legume forage (Arachis pintoi) resulted in a good growth rate (12 g/d) even though this gain was much lower than that obtained with a commercial control diet (31 g/d) (Nieves et al., 1996).
Elephant grass hay was safely introduced in complete balanced diets up to 20-25%, as the main source of fibre, provided that its low protein content (9-10%) and high fibre level of fibre (40-45% ADF) were taken into account (Raharjo et al., 1988; Tangendjaja et al., 1990). Nevertheless, the low concentration of the protein in lysine (about 60% of requirements), and particularly in sulphur-containing amino acids (about 40-50% of requirements), should be considered. Depending on its protein and fibre content, the digestible energy content of elephant grass may vary from 6.0-6.5 to 7.9 MJ/kg DM (Raharjo et al., 1986).
Avg: average or predicted value; SD: standard deviation; Min: minimum value; Max: maximum value; Nb: number of values (samples) used
| Main analysis | Unit | Avg | SD | Min | Max | Nb | |
| Dry matter | % as fed | 17.9 | 5.9 | 8.6 | 41.0 | 1036 | |
| Crude protein | % DM | 9.7 | 4.3 | 2.8 | 22.7 | 2209 | |
| Crude fibre | % DM | 36.1 | 3.9 | 25.5 | 43.2 | 1091 | * |
| NDF | % DM | 71.5 | 7.1 | 54.1 | 79.9 | 433 | * |
| ADF | % DM | 42.5 | 6.4 | 29.5 | 52.9 | 377 | * |
| Lignin | % DM | 5.7 | 1.5 | 2.7 | 9.1 | 365 | * |
| Ether extract | % DM | 2.0 | 0.6 | 1.0 | 3.8 | 1022 | |
| Ash | % DM | 13.8 | 4.8 | 3.9 | 25.1 | 2200 | |
| Gross energy | MJ/kg DM | 17.4 | 1.1 | 16.0 | 18.9 | 5 | * |
| Minerals | Unit | Avg | SD | Min | Max | Nb | |
| Calcium | g/kg DM | 3.6 | 1.3 | 1.4 | 7.6 | 1160 | |
| Phosphorus | g/kg DM | 2.9 | 1.2 | 0.7 | 6.6 | 1762 | |
| Potassium | g/kg DM | 29.0 | 13.9 | 4.9 | 68.0 | 1207 | |
| Sodium | g/kg DM | 0.3 | 0.2 | 0.0 | 0.8 | 89 | |
| Magnesium | g/kg DM | 3.0 | 1.1 | 1.3 | 6.2 | 1031 | |
| Manganese | mg/kg DM | 91 | 56 | 19 | 238 | 38 | |
| Zinc | mg/kg DM | 45 | 26 | 20 | 129 | 45 | |
| Copper | mg/kg DM | 11 | 4 | 5 | 24 | 55 | |
| Iron | mg/kg DM | 413 | 323 | 82 | 1175 | 21 | |
| Amino acids | Unit | Avg | SD | Min | Max | Nb | |
| Arginine | % protein | 2.5 | 2.1 | 3.0 | 2 | ||
| Cystine | % protein | 0.2 | 1 | ||||
| Histidine | % protein | 1.6 | 1.4 | 1.9 | 2 | ||
| Isoleucine | % protein | 3.9 | 3.1 | 4.7 | 2 | ||
| Leucine | % protein | 5.7 | 5.2 | 6.2 | 2 | ||
| Lysine | % protein | 3.1 | 3.1 | 3.1 | 2 | ||
| Methionine | % protein | 1.4 | 1 | ||||
| Phenylalanine | % protein | 3.6 | 1 | ||||
| Threonine | % protein | 3.6 | 3.5 | 3.8 | 2 | ||
| Tryptophan | % protein | 0.6 | 1 | ||||
| Tyrosine | % protein | 4.9 | 1 | ||||
| Valine | % protein | 5.1 | 4.4 | 5.9 | 2 | ||
| Secondary metabolites | Unit | Avg | SD | Min | Max | Nb | |
| Tannins (eq. tannic acid) | g/kg DM | 22.2 | 1 | ||||
| Tannins, condensed (eq. catechin) | g/kg DM | 12.4 | 3.0 | 21.8 | 2 | ||
| Ruminant nutritive values | Unit | Avg | SD | Min | Max | Nb | |
| OM digestibility, ruminants | % | 61.4 | 3.8 | 55.4 | 70.6 | 30 | * |
| OM digestibility, ruminants (gas production) | % | 67 | 1 | ||||
| Energy digestibility, ruminants | % | 58.7 | 56.9 | 72.5 | 2 | * | |
| DE ruminants | MJ/kg DM | 10.2 | * | ||||
| ME ruminants | MJ/kg DM | 8.2 | * | ||||
| ME ruminants (gas production) | MJ/kg DM | 8.2 | 1.1 | 6.4 | 9.2 | 5 | |
| Nitrogen digestibility, ruminants | % | 57.3 | 11.9 | 33.0 | 73.0 | 34 | |
| c (N) | h-1 | 0.012 | 1 |
The asterisk * indicates that the average value was obtained by an equation.
References
Abdulrazak et al., 1996; Abou-Ashour et al., 1984; AFZ, 2011; Aguiar et al., 2006; Ajayi et al., 2011; Aka et al., 2004; Alibes et al., 1990; Aumont et al., 1991; Axtmayer et al., 1940; Babayemi, 2007; Bartha, 1970; Bayble et al., 2007; Butterworth, 1963; Butterworth, 1965; Calles et al., 1982; Carvalho Junior et al., 2009; CGIAR, 2009; CIRAD, 1991; Clipes et al., 2006; Demeterova et al., 1991; Dixon, 1986; Dongmeza et al., 2009; Elliott, 1956; Evitayani et al., 2004; Evitayani et al., 2004; French, 1943; Garcia et al., 2008; González-García et al., 2008; Gowda et al., 2004; Hassan et al., 1979; Hassoun, 2009; Holm, 1971; Holm, 1971; Iyeghe-Erakpotobor et al., 2008; Juma et al., 2006; Kaitho et al., 1998; Kambashi et al., 2014; Khanum et al., 2007; Komwihangilo et al., 2007; Kumar et al., 2012; Lacerda et al., 2004; Lanyasunya et al., 2006; Lim Han Kuo, 1967; Lin et al., 1988; ListaI et al., 2008; Mahyuddin et al., 1988; Marshall et al., 1963; Mecha et al., 1980; Mendieta-Araica et al., 2009; Mendieta-Araica et al., 2011; Mendieta-Araica et al., 2011; Mlay et al., 2006; Mtui et al., 2006; Nasrullah et al., 2003; Ngo Van Man et al., 2003; Niang et al., 1998; Njwe et al., 1990; Nordfeldt et al., 1952; Olubajo et al., 1974; Osuga et al., 2006; Palafox et al., 1961; Palieraqui et al., 2006; Pozy et al., 1996; Ribeiro Filho et al., 2000; Richard et al., 1989; Sarwatt et al., 2004; Shem et al., 1999; Shibata et al., 1988; Teguia et al., 1999; Telford et al., 1947; Tisserand et al., 1989; Tuah et al., 1974; Van Eys et al., 1986; Van Eys et al., 1987; Vicente Chandler et al., 1974; Warly et al., 2006; Xandé et al., 1989
Last updated on 22/01/2015 17:40:13
| Main analysis | Unit | Avg | SD | Min | Max | Nb | |
| Dry matter | % as fed | 89.3 | 6.8 | 79.2 | 98.3 | 8 | |
| Crude protein | % DM | 10.3 | 3.3 | 5.5 | 15.1 | 18 | |
| Crude fibre | % DM | 35.6 | 2.7 | 34.5 | 40.3 | 4 | * |
| NDF | % DM | 71.1 | 5.5 | 60.8 | 79.1 | 16 | * |
| ADF | % DM | 41.9 | 6.2 | 33.0 | 50.2 | 16 | * |
| Lignin | % DM | 5.8 | 2.7 | 4.1 | 12.9 | 15 | * |
| Ether extract | % DM | 1.9 | 0.5 | 1.3 | 2.5 | 7 | |
| Ash | % DM | 10.9 | 2.0 | 5.3 | 13.2 | 18 | |
| Gross energy | MJ/kg DM | 17.9 | * | ||||
| Minerals | Unit | Avg | SD | Min | Max | Nb | |
| Calcium | g/kg DM | 2.8 | 0.2 | 2.5 | 2.9 | 3 | |
| Phosphorus | g/kg DM | 2.3 | 0.4 | 1.8 | 2.6 | 3 | |
| Potassium | g/kg DM | 26.7 | 13.7 | 13.6 | 40.9 | 3 | |
| Magnesium | g/kg DM | 1.6 | 0.5 | 1.3 | 2.2 | 3 | |
| Ruminant nutritive values | Unit | Avg | SD | Min | Max | Nb | |
| OM digestibility, ruminants | % | 58.7 | 9.0 | 44.5 | 72.4 | 13 | * |
| Energy digestibility, ruminants | % | 55.3 | * | ||||
| DE ruminants | MJ/kg DM | 9.9 | * | ||||
| ME ruminants | MJ/kg DM | 7.9 | * | ||||
| Nitrogen digestibility, ruminants | % | 59.4 | 10.2 | 40.7 | 73.2 | 7 | |
| a (N) | % | 20.9 | 1 | ||||
| b (N) | % | 60.8 | 1 | ||||
| c (N) | h-1 | 0.024 | 1 | ||||
| Nitrogen degradability (effective, k=4%) | % | 44 | * | ||||
| Nitrogen degradability (effective, k=6%) | % | 38 | * |
The asterisk * indicates that the average value was obtained by an equation.
References
Aguiar et al., 2006; Aguiar et al., 2006; Anele et al., 2011; Chiou et al., 1995; CIRAD, 1991; Flores et al., 1993; Kozloski et al., 2003; Sarwar et al., 1999; Schnaider et al., 2014; Van Wyk et al., 1951; Zetina-Cordoba et al., 2012
Last updated on 22/01/2015 17:45:08
| Main analysis | Unit | Avg | SD | Min | Max | Nb | |
| Dry matter | % as fed | 19.5 | 6.1 | 9.1 | 25.9 | 8 | |
| Crude protein | % DM | 6.5 | 2.1 | 4.2 | 10.5 | 10 | |
| Crude fibre | % DM | 37.0 | 4.5 | 29.7 | 42.7 | 6 | |
| NDF | % DM | 72.6 | 20.1 | 42.7 | 77.7 | 3 | * |
| ADF | % DM | 43.6 | 10.6 | 28.0 | 52.0 | 4 | * |
| Lignin | % DM | 6.2 | * | ||||
| Ether extract | % DM | 1.8 | 0.9 | 0.9 | 3.8 | 9 | |
| Ash | % DM | 12.6 | 2.6 | 9.0 | 15.7 | 10 | |
| Gross energy | MJ/kg DM | 17.4 | * | ||||
| Minerals | Unit | Avg | SD | Min | Max | Nb | |
| Calcium | g/kg DM | 2.5 | 1.3 | 1.2 | 3.8 | 3 | |
| Phosphorus | g/kg DM | 3.6 | 1.9 | 1.5 | 4.9 | 3 | |
| Potassium | g/kg DM | 36.4 | 6.1 | 29.5 | 41.2 | 3 | |
| Magnesium | g/kg DM | 2.3 | 0.5 | 1.8 | 2.7 | 3 | |
| Ruminant nutritive values | Unit | Avg | SD | Min | Max | Nb | |
| OM digestibility, ruminants | % | 57.9 | * | ||||
| Energy digestibility, ruminants | % | 53.7 | * | ||||
| DE ruminants | MJ/kg DM | 9.3 | * | ||||
| ME ruminants | MJ/kg DM | 7.5 | * | ||||
| Nitrogen digestibility, ruminants | % | 62.0 | 1 | ||||
| a (N) | % | 48.8 | 1 | ||||
| b (N) | % | 12.9 | 1 | ||||
| c (N) | h-1 | 0.068 | 1 | ||||
| Nitrogen degradability (effective, k=4%) | % | 57 | * | ||||
| Nitrogen degradability (effective, k=6%) | % | 56 | * |
The asterisk * indicates that the average value was obtained by an equation.
References
Chizzotti et al., 2005; CIRAD, 1991; Elliott, 1956; Marcondes et al., 2009; Rêgo et al., 2010; Tuah et al., 1974; Xandé et al., 1989
Last updated on 22/01/2015 17:43:20
Heuzé V., Tran G., Giger-Reverdin S., Lebas F., 2020. Elephant grass (Pennisetum purpureum). Feedipedia, a programme by INRAE, CIRAD, AFZ and FAO. https://www.feedipedia.org/node/395 Last updated on October 5, 2020, 10:34