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Animal feed resources information system
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Rice hulls

IMPORTANT INFORMATION: This datasheet is pending revision and updating; its contents are currently derived from FAO's Animal Feed Resources Information System (1991-2002) and from Bo Göhl's Tropical Feeds (1976-1982).

Datasheet

Description
Click on the "Nutritional aspects" tab for recommendations for ruminants, pigs, poultry, rabbits, horses, fish and crustaceans
Common names 

Rice hulls, chaff, rice husks

Synonyms 

Oryza glutinosa Lour., Oryza sativa var. affinis Körn., Oryza sativa var. erythroceros Körn., Oryza sativa var. flavoacies Kara-Murza ex Zhuk., Oryza sativa subsp. indica Kato., Oryza sativa cv. italica Alef., Oryza sativa subsp. japonica auct., Oryza sativa var. japonica auct., Oryza sativa var. melanacra Körn., Oryza sativa var. suberythroceros Kanevsk, Oryza sativa var. vulgaris Körn., Oryza sativa var. zeravschanica Brches ex Katzaroff, nom. nud. (USDA, 2009)

Description 

Rice hulls are the by-product of rice dehulling. They are used in some countries for poultry litter that can later be fed to ruminants. Numerous publications on uses of rice hulls attest to the many attempts to solve the problem of disposing of this by-product.

Distribution 

Rice originates from Asia where it is known to have been growing since 6500 BC. It was then brought to all tropical regions within centuries. Rice grows from 53°N in China to 35°S in Australia. The optimal growing conditions are: 20-30°C average day-temperature with night temperature over 15°C; fertile, heavy soils, 6.5-7 pH. Most varieties ("swamp rice", "lowland rice") must be planted in stagnant water and require 200 mm rainfall/month or equivalent amount from irrigation, whereas others ("mountain rice" or "upland rice") require less irrigation and 750 mm rainfall on a 3-4 months period and no dessication.

Environmental impact 

Irrigated rice causes anaerobic fermentation in the soil, subsequently producing high amounts of CH4 (6 to 29% of the total amount of anthropogenic CH4 emissions) one of the most important greenhouse gases (Neue et al., 1993). Lodging also causes acidification and increases salinity. Water specific demand for rice is ranging from 2000 to 3000 l/kg which is slightly higher than other crops like legumes or wheat (Hoekstra, 2003).

Nutritional aspects
Ruminants 

Rice hulls can be used in animal feeding in the following ways:

  1. As raw rice hulls. Low-quality roughages like ground rice hulls can be included in small amounts (up to 15%) in high-concentrate diets for feedlot cattle to help furnish bulk, stimulate appetite and decrease incidence of liver abscesses. In areas with a shortage of roughage, ground rice hulls can be used in place of straw or advantageously as a partial replacement for it. The addition of ground rice hulls has been found in some cases to increase the feed intake.
  2. As ammoniated rice hulls. A process developed for making livestock feed from hulls includes the addition of monocalcium phosphate, removal of silica, ammoniation under pressure and toasting. Ammoniated rice hulls have been used in proportions of up to 40% of the total ration for sheep, without digestive or mastication problems.
  3. Together with bran and polishings.
Horses and donkeys 

In Australia, ground rice hulls have been used successfully in lower energy horse feeds at 25% inclusion in the pelleted part of the ration (Hutton, 1990).

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

IMPORTANT INFORMATION: This datasheet is pending revision and updating; its contents are currently derived from FAO's Animal Feed Resources Information System (1991-2002) and from Bo Göhl's Tropical Feeds (1976-1982).

Main analysis Unit Avg SD Min Max Nb
Dry matter % as fed 91.9 2.0 88.1 95.4 35
Crude protein % DM 3.7 1.4 1.9 6.7 35
Crude fibre % DM 42.6 6.8 28.1 56.8 35
NDF % DM 67.8 11.7 46.0 79.2 17
ADF % DM 51.7 11.0 31.6 72.0 17
Lignin % DM 14.2 3.7 6.1 19.2 15
Ether extract % DM 1.5 1.1 0.4 4.2 27
Ash % DM 17.5 3.1 12.9 24.1 37
Starch (polarimetry) % DM 5.3 3.7 0.8 11.9 13
Gross energy MJ/kg DM 16.3 1.4 14.7 18.1 5 *
 
Minerals Unit Avg SD Min Max Nb
Calcium g/kg DM 0.9 0.4 0.3 1.7 19
Phosphorus g/kg DM 1.1 1.0 0.3 4.0 20
Potassium g/kg DM 4.0 1.7 1.7 7.3 16
Sodium g/kg DM 0.3 0.2 0.1 0.4 3
Magnesium g/kg DM 1.0 1.1 0.3 4.4 16
Manganese mg/kg DM 442 435 448 2
Zinc mg/kg DM 43 1
Copper mg/kg DM 2 1
Iron mg/kg DM 56 1
 
Ruminant nutritive values Unit Avg SD Min Max Nb
OM digestibility, Ruminant % 28.9 1
Energy digestibility, ruminants % 22.8 *
DE ruminants MJ/kg DM 3.7 *
ME ruminants MJ/kg DM 3.0 *
Nitrogen digestibility, ruminants % 7.4 1
 
Rabbit nutritive values Unit Avg SD Min Max Nb
Energy digestibility, rabbit % 36.3 *
DE rabbit MJ/kg DM 5.9 1

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

References

Abdekalam, 1975; AFZ, 2011; CIRAD, 1991; Cirad, 2008; Enueme et al., 1987; Fernandez Carmona et al., 1996; Fraga et al., 1991; Karunajeewa et al., 1987; Krishna, 1985; Krishna, 1985; Lim Han Kuo, 1967; Mopaté et al., 2011; Nguyen Nhut Xuan Dung et al., 2002; Ohlde et al., 1982; Storey et al., 1982

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

References
Datasheet citation 

DATASHEET UNDER CONSTRUCTION. DO NOT QUOTE. http://www.feedipedia.org/node/749 Last updated on March 6, 2011, 16:07

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