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Guinea grass (Megathyrsus maximus)

Datasheet

Description
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Common names 

General types

Guinea grass, Tanganyika grass, buffalograss [English]; pasto guinea, mijo de guinea, gramalote [Spanish]; capim-mombaça, capim guine, capim colonião, capim de Angola, capim de feixe, erva-da-guiné [Portuguese/Brazil]; talapi, tinikarati [Cook Islands]; capime guiné, fataque, herbe de guinée, panic élevé [French]; rumput banggala, rumput gajah, suket londo [Indonesian]; erba di guinea [Italian]; rebha luh buluhan, rumput benggala, rumput sarang sesak [Malay]; gewone buffelsgras [Afrikaans]; saafa [Tonga]; güyana otu [Turkish]; vao kini [Samoa]; cỏ ghi nê [Vietnamese]; الثمام الكبير ,الدخن الكبير [Arabic]; 大黍 [Chinese]

Short types

Panic, green panic, slender guinea grass, castilla

Synonyms 

Panicum maximum Jacq., Panicum maximum var. coloratum C. T. White, Panicum maximum var. hirsutissimum (Steud.) Oliv., Panicum maximum var. pubiglume K. Schum., Panicum maximum var. trichoglume Robyns, Panicum hirsutissimum Steud. (USDA, 2009)

Taxonomic information 

Guinea grass used to be known as Panicum maximum Jacq. In 2003, the subgeneric name Megathyrsus was raised to generic rank and the plant was renamed Megathyrsus maximus (Jacq.) B. K. Simon & S. W. L. Jacobs (Simon et al., 2003). However, the name Panicum maximum is still found in literature posterior to 2003.

Description 

Guinea grass (Megathyrsus maximus (Jacq.) B. K. Simon & S. W. L. Jacobs) is a major pantropical grass used throughout the tropics for pasture, cut-and-carry, silage and hay. It is a fast growing and leafy grass, which is palatable to livestock with a good nutritional value. However, it is generally recommended to supplement it with sources of protein in order to meet nutritional requirements or improve animal performance.

Morphology

Guinea grass is a large tufted, fast-growing perennial grass. It has a broad morphological and agronomic variability, ranging in height from 0.5 to 3.5 m, with stems of 5 mm to 10 mm diameter. There are two main types: a tall/medium tussock type, taller than 1.5 m at flowering, and a short tussock type (Cook et al., 2005). The root is a short creeping rhizome; culms are erect, hirsute at the nodes. Leaves are blade-shaped, glabrous to pubescent up to 35 mm broad. Inflorescence is a panicle, 15 to 50 cm long. Spikelets are 3-4 mm green to purple (Ecoport, 2009).

Utilization

Guinea grass is suitable for pasture, cut-and-carry, silage and hay. Many Guinea grass cultivars have been developed for different purposes and agronomic situations (FAO, 2009).

Distribution 

Guinea grass is native to tropical Africa and is now widely naturalized in the tropics. It is naturally found in open grasslands, woodland and shady places within 16.3°N and 28.7°S.

It grows best under an annual rainfall above 1000 mm with no more than a 4 to 5 month dry period. Average annual day-temperature should range from 19.1°C to 22.9°C. Small types are more tolerant of cooler temperatures than tall types. It prefers well-drained, moist and fertile soils (Cook et al., 2005). It is tolerant of light frost and low soil pH if drainage is good (FAO, 2009) and also of high Al3+ saturation (Ecoport, 2009). It is well adapted to sloping, cleared land in rainforest areas (FAO, 2009). Drought tolerance depends on the cultivar, but should not generally exceed 4 or 5 months. Guinea grass can be sown with companion legumes such as Centrosema pubescens, Leucaena leucocephala, Pueraria phaseoloides or Macroptilium atropurpureum (Cook et al., 2005).

Forage management 

Use for pasture, silage and hay

Guinea grass is well suited for cut-and-carry systems and can be used for making silage and hay. Guinea grass can be managed as a long-term pasture grass if grazed consistently, but it should not be grazed under 35 cm height, nor under very wet conditions (FAO, 2009). As the grass rest-period affects animal performance, a good rest-period is to wait for regrowth of 2.5 leaves/tiller (Candido et al., 2005). For silage and hay, a good cutting height is 60-90 cm, but for higher yields of acceptable quality it can be cut at up to 1.5 m, as it does not become coarse even if left to grow to that height (Hongthong Phimmasan, 2005). Better quality silage is obtained if Guinea grass is cut during pre-anthesis or anthesis (Sarwatt et al., 1989). Ensiled Guinea grass has a good texture and it was possible to mix grass of different ages with no effect on silage quality (Babayemi et al., 2009). 

Yields

Guinea grass yields an average of 30 t DM/ha/year (Cook et al., 2005). The yields depend on the cultivar and fertilizer application. For instance, unfertilized Guinea grass yields around 7t DM/ha while N-fertilized pastures can yield up to 42t/ha (Hongthong Phimmasan, 2005). Guinea grass produces around 1.7-3.1 million seeds/kg (Ecoport, 2009).

Environmental impact 

Guinea grass is a fast growing, bulky grass that helps prevention of soil erosion since it provides rapid ground cover (Roose, 1994). While it spreads slowly when it is well managed, Guinea grass can spread very fast and become a weed in ungrazed areas where soil disturbance has occurred. It is a major weed in sugarcane fields since it grows well in shaded conditions (Ecoport, 2009).

Nutritional aspects
Potential constraints 

Traces of HCN in Guinea grass are reported as well as small amounts of oxalic acid (0.28%) (Ndyanabo, 1974 cited by FAO, 2009). Continuous feeding of oxalates has been implicated in hyperparathyroidism ("big head") in horses, and occasionally nephrosis or hypocalcaemia in ruminants (Miyazaki et al., 2003).

In South Africa, it is suspected to cause photodermatitis in sheep ("dikoor", literally "thick ear"), perhaps in conjunction with the smut fungus Ustilago (Botha et al., 2002). The plant is also said to cause fatal colic if eaten too wet or in excess, particularly in Equidae (Duke, 1983; Cerqueira et al., 2009).

Ruminants 

Guinea grass is a valuable fodder for pasture, hay and silage. However, it is generally preferable to supplement it with sources of protein to improve animal performance.

Palatability

Guinea grass is well eaten by all classes of grazing livestock, with particularly high intakes of young leafy plants (Cook et al., 2005).

Digestibility

Reported OM digestibility values range from 53 to 79%. The best OM and DM digestibilities are obtained with young regrowth (Peiris et al., 1995). 

Dairy cattle

In South America, cows grazing Guinea grass yielded 10 to 12 kg milk/day at 2.5 head/ha with good sward persistence and high forage quality (Lima et al., 2006; Lamela et al., 1995). Dairy heifers stocked at 2.3 head/ha on Guinea grass pasture gained 1 kg/ha/d (Costa et al., 2001). Several experiments have shown that supplementing cows or dairy heifers fed on Guinea grass improves animal performance. Supplementation with a concentrate or a concentrate and a legume gave greater milk yields in cows (Goncalves et al., 2005; Razz et al., 2007; Goncalves et al., 2003) and higher weight gains (+35%) in heifers (Rodrigues Filho et al., 2004).

Growing cattle

Steers can graze Guinea grass (Difante et al., 2009). Intercropping or supplementing Guinea grass with legumes increased Ca, P, Na and Fe solubility (Ajayi et al., 2009), DM intake (Akinlade et al., 2005) and did not alter meat quality (Jaturasitha et al., 2009). Guinea grass cv. Monbaca gives higher daily weight gains while cv. Masai allows higher stocking rate (Euclides et al., 2008). Adding 60% autoclaved broiler litter to a Guinea grass-based diet in Zebu heifers increased the intake of digestible nutrients and body weight gain (Belewu, 1998).

Sheep

The protein content of Guinea grass pasture was found insufficient for meeting the nutritional requirement of lambs in South Africa (Relling et al., 2001) and in the Fiji (Aregheore et al., 2004). It was suggested to supplement Guinea grass with a concentrate or with a legume (Aschfalk et al., 2002; Brown et al., 1995). In sheep fed on a Guinea grass hay-based diet, urea treatment or supplementation with poultry manure helped to improve feed conversion ratio and growth performance (Yousuf et al., 2007; Brown et al., 1995). Exogenous fibrolytic enzyme had no effect on rumen digestibility of Guinea grass hay (Avellaneda et al., 2009). Iodinated casein was found to increase rumen potential degradability of Guinea grass (Silva et al., 2007).

Goats

Feeding goats with Guinea grass gives better results when it is supplemented with a legume (Ajayi et al., 2008; Bamikole, 2003; Viengsavanh Phimphachanhvongsod et al., 2002) or a crop residue-based concentrate (Aregheore, 2003). Supplementation increased feed intake and nutrient utilization (Viengsavanh Phimphachanhvongsod et al., 2002; Bamikole et al., 2001).

Poultry 

Guinea grass leaf meal could be used to feed broiler chickens at 15% of the diet in place of maize. It had no effect on meat quality (Oluwasola et al., 2008).

Rabbits 

Guinea grass is palatable to rabbits (Adehan et al., 1994). Rabbits fed on Guinea grass had a higher feed intake and Guinea grass voluntary intake was 75% of the overall intake (Taiwo et al., 2005). It was also a good fibre complement in water spinach-based diet (Khuc Thi Hue et al., 2006). However, it was reported to decrease digestibility coefficients when added at 25% of the diet (Gupta et al., 1993). Replacing Guinea grass with water spinach (Ipomoea aquatica) resulted in higher body weight gains in growing rabbits and higher milk yield and litter size in does (Tran Hoang Chat et al., 2005).

Nutritional tables
Tables of chemical composition and nutritional value 

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 22.7 7.4 10.2 47.4 1835
Crude protein % DM 11.2 4.3 3.2 21.4 2396
Crude fibre % DM 37.3 3.7 27.7 46.9 2218
NDF % DM 72.3 6.5 54.1 80.2 245 *
ADF % DM 43.4 5.4 28.2 49.8 178 *
Lignin % DM 6.1 1.0 3.3 7.6 177 *
Ether extract % DM 1.8 0.6 0.8 3.8 2077
Ash % DM 10.5 2.3 6.1 18.2 2218
Gross energy MJ/kg DM 18.1 0.5 16.9 19.2 21 *
 
Minerals Unit Avg SD Min Max Nb
Calcium g/kg DM 4.9 1.7 1.9 17.5 2147
Phosphorus g/kg DM 2.4 0.9 0.8 4.7 2156
Potassium g/kg DM 23.1 9.3 5.7 50.3 2054
Sodium g/kg DM 2.7 2.2 0.3 8.0 86
Magnesium g/kg DM 3.4 1.3 1.4 7.2 2040
Manganese mg/kg DM 127 57 49 269 122
Zinc mg/kg DM 30 8 18 52 123
Copper mg/kg DM 6 2 3 10 123
Iron mg/kg DM 279 232 132 683 5
 
Amino acids Unit Avg SD Min Max Nb
Arginine % protein 4.9 1
Cystine % protein 1.4 1
Histidine % protein 1.8 1
Isoleucine % protein 4.3 1
Leucine % protein 8.4 1
Lysine % protein 5.6 1
Methionine % protein 2.1 1
Phenylalanine % protein 5.3 1
Threonine % protein 4.7 1
Tryptophan % protein 2.2 1
Valine % protein 6.6 1
 
Secondary metabolites Unit Avg SD Min Max Nb
Tannins (eq. tannic acid) g/kg DM 5.6 1.0 10.1 2
Tannins, condensed (eq. catechin) g/kg DM 0.0 1
 
Ruminant nutritive values Unit Avg SD Min Max Nb
OM digestibility, Ruminant % 59.2 6.5 52.6 79.2 50 *
OM digestibility, ruminants (gas production) % 65 1
Energy digestibility, ruminants % 55.3 51.5 59.1 2
DE ruminants MJ/kg DM 10.0 *
ME ruminants MJ/kg DM 8.0 *
ME ruminants (gas production) MJ/kg DM 7.9 0.7 7.1 8.9 5
Nitrogen digestibility, ruminants % 61.8 11.8 31.5 81.9 61
a (N) % 25.3 16.7 1.2 40.3 6
b (N) % 43.0 18.6 6.8 55.0 6
c (N) h-1 0.038 0.021 0.007 0.058 6
Nitrogen degradability (effective, k=4%) % 46 *
Nitrogen degradability (effective, k=6%) % 42 15 2 65 16 *

The asterisk * indicates that the average value was obtained by an equation.

References

Abaunza et al., 1991; Adejumo et al., 1991; Adeneye et al., 1994; Ajayi et al., 2005; Ajayi et al., 2008; Ajayi et al., 2009; Aka et al., 2004; Akinlade et al., 2002; Anugwa, 1990; Aregheore et al., 2006; Aschfalk et al., 2002; Aumont et al., 1991; Babayemi et al., 2006; Babayemi et al., 2009; Babayemi, 2007; Balogun et al., 1998; Balsalobre et al., 2003; Bamikole et al., 2001; Bamikole et al., 2003; Bamikole et al., 2004; Bamikole, 2003; Blair Ralns, 1963; Boukary-Mori, 2000; Brancio et al., 2003; Buntha et al., 2006; Caceres et al., 1986; Candido et al., 2005; CGIAR, 2009; CIRAD, 1991; Clipes et al., 2006; Devasena et al., 1994; Dzowela et al., 1990; Evitayani et al., 2004; Evitayani et al., 2004; French, 1943; Gerdes et al., 2000; Giraldo et al., 1995; Gomez Cabrera, 2009; González-García et al., 2008; Gowda et al., 2004; Holm, 1971; Ibrahim et al., 1995; Ifut, 1992; Jones et al., 2000; Kabaija et al., 1988; Kabuga et al., 1993; Kaligis et al., 1990; Khuc Thi Hue et al., 2006; Komwihangilo et al., 2007; Lanyasunya et al., 2006; Lim Han Kuo, 1967; Lima et al., 2004; Lin et al., 1988; ListaI et al., 2008; Mlay et al., 2006; Nasrullah et al., 2003; Navaratne et al., 1990; Ngo Van Man et al., 2003; Niekerk et al., 2002; Odedire et al., 2008; Ojeda et al., 1993; Olubajo et al., 1974; Palieraqui et al., 2006; Panditharatne et al., 1978; Pereira et al., 2001; Pozy et al., 1996; Prado et al., 2004; Relling et al., 2001; Relling et al., 2001; Richard et al., 1989; Rodrigues et al., 2004; Rokomatu et al., 2005; Sarwatt et al., 1989; Saxena et al., 1972; Singh et al., 1992; Singh et al., 1996; Souza et al., 2003; Taute et al., 2002; Taute et al., 2002; Tedeschi et al., 2001; Tran Hoang Chat et al., 2005; Velloso et al., 1978; Velloso et al., 1983; Viengsavanh Phimphachanhvongsod et al., 2002; Villarreal et al., 1994; Warly et al., 2010; Xandé et al., 1989; Yadav et al., 1991

Last updated on 24/10/2012 00:43:10

Main analysis Unit Avg SD Min Max Nb  
Dry matter % as fed 89.8 2.9 83.4 93.4 61  
Crude protein % DM 9.1 3.1 4.0 13.8 94  
Crude fibre % DM 36.7 4.0 30.3 44.7 55  
NDF % DM 71.7 3.4 68.3 81.5 38 *
ADF % DM 42.7 4.9 36.9 53.7 40 *
Lignin % DM 6.0 1.7 3.8 8.8 39 *
Ether extract % DM 1.6 0.4 1.0 2.5 54  
Ash % DM 11.5 2.0 6.6 14.2 78  
Gross energy MJ/kg DM 17.7 0.3 17.7 19.1 4 *
               
Minerals Unit Avg SD Min Max Nb  
Calcium g/kg DM 4.6 1.6 2.8 9.3 45  
Phosphorus g/kg DM 3.0 0.9 1.4 4.3 46  
Potassium g/kg DM 16.3 7.7 6.8 40.2 41  
Sodium g/kg DM 3.1 2.9 0.4 8.6 17  
Magnesium g/kg DM 3.0 1.1 1.7 5.9 35  
Manganese mg/kg DM 152 71 23 262 14  
Zinc mg/kg DM 35 5 29 48 15  
Copper mg/kg DM 6 2 2 10 15  
               
Ruminant nutritive values Unit Avg SD Min Max Nb  
OM digestibility, Ruminant % 57.3 4.5 49.2 65.4 28 *
Energy digestibility, ruminants % 53.9         *
DE ruminants MJ/kg DM 9.5         *
ME ruminants MJ/kg DM 7.7         *
Nitrogen digestibility, ruminants % 54.8 12.2 36.0 71.3 10  

The asterisk * indicates that the average value was obtained by an equation.

References

Abdulrazak et al., 2006; Babayemi et al., 2009; Calles et al., 1982; CIRAD, 1991; Holm, 1971; Holm, 1971; Ibrahim et al., 1990; McLeod et al., 1990; Minson, 1971; Richard et al., 1989; Silanikove et al., 1990; Yousuf et al., 2007; Zhao et al., 1993

Last updated on 07/11/2012 17:20:36

Main analysis Unit Avg SD Min Max Nb
Dry matter % as fed 92.5 1.0 91.6 93.6 3
Crude protein % DM 4.3 1.7 2.4 5.8 3
Crude fibre % DM 40.4 3.5 36.4 43.0 3
NDF % DM 75.1 5.5 68.8 78.8 3
ADF % DM 44.7 41.0 48.4 2
Lignin % DM 5.0 2.0 3.0 6.9 3
Ether extract % DM 1.4 0.3 1.2 1.7 3
Ash % DM 12.2 5.3 8.1 18.2 3
Gross energy MJ/kg DM 17.4 *
 
Minerals Unit Avg SD Min Max Nb
Calcium g/kg DM 4.7 1
Phosphorus g/kg DM 2.6 1
Sodium g/kg DM 10.1 1
Manganese mg/kg DM 16 1

The asterisk * indicates that the average value was obtained by an equation.

References

Parigi-Bini et al., 1991

Last updated on 24/10/2012 00:43:11

References
References 
Datasheet citation 

Heuzé V., Tran G., 2015. Guinea grass (Megathyrsus maximus). Feedipedia, a programme by INRA, CIRAD, AFZ and FAO. http://www.feedipedia.org/node/416 Last updated on June 19, 2015, 14:45

English correction by Tim Smith (Animal Science consultant) and Hélène Thiollet (AFZ)