http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 가렛트 (검색결과 1 건)
- 무료
- 기관 내 무료
- 유료
-
한인규,W . N . 가렛트 ( I . K . Han,W . N . Garrett ) 한국축산학회 1986 한국축산학회지 Vol.28 No.4
Approximately 450 scientific articles including over 20 review papers (mostly published in the last 2 decades) have been reviewed to evaluate and compare the nutritional characteristics of treated and untreated low quality roughages (mostly crop residues). Attempts have also been made to explain the possible mechanisms for the improvement in nutritive value of treated lignocellulosic materials and to expose some problems associated with various treatments. (1) Over 2,000 million metric tons of crop residues are produced every year in the world. Wheat straw (25.3%), rice straw (22.8%), corn stover (15.8%), sugar cane residues (14.4%) and barley straw (8.3%) are the major crop residues. Of total production of crop residues, Asia, North America, and Europe are producing 46%, 19% and 13%, respectively. Forty types of low quality roughage have been examined with regard to improving their nutritive value by various treatments. These can be listed as follows. A. Crap residues and agricultural by-products: Rice straw, oat straw, wheat straw, barley straw, corn stover, corn cobs, sunflower stover, sugar cane top, cassava wastes, cassava leaves, sorghum stover, millet stover, peanut hull, soybean residues, cotton by-product, cotton straw, pea straw, rice hull, sugar cane bagasse, cotton hull, and alfalfa stem. B. Wood and wood by-products: aspen, poplar, spruce, black ash, American basswood, yellow birch, eastern cottonwood, American elm, silver maple, sugar maple, red oak, white oak, quaking aspen, white birch, soft maple, and ponderosa pine. C. Native herbages: wild (native or range) grasses. D. Animal wastes: cow manure, poultry manure. (2) Most crop residues and low quality rough ages are nutritionally known to be low in energy, crude protein, calcium, phosphorus, some trace minerals and carotene and quite high in crude fiber, ADF, cellulose, hemicellulose, lignin and silica. Their digestibilities of cellulose and bioavailability of energy are low and voluntary feed intake is also low. Thus, most untreated lignocellulosic materials could not be classified as maintenance feeds of animals. (3) Since the Beckman method of sodium hydroxide treatment was developed in 1921, more than 30 treatment procedures were found to be effective in improving the nutritive value of low quality roughages. A. Physical treatments: soaking, grinding, steam pressure, explosion, irradiation, pelleting, and supplementation. 8. Chemical treatments: Beckman NaOH, wet chamber NaOH, Dip NaOH, spray NaOH, urine, urea, anhydrous ammonia stack, aqueous ammonia, calcium oxide (lime), calcium hydroxide, potassium hydroxide, sodium carbonate, sulphur dioxide, sodium chlorite, ozone, chelating metal caustic swelling, hydrogen peroxide, peracetic acid. C. Physico-chemical treatment: sodium hydroxide and pelleting. D. Biological treatments: fermentation, enzyme, silage, manure·silage. (4) Present review data reveal that chemical (36.2%), biological (36.2%), physical (31.1%) and physico-chemical treatments (30.3%) could all significantly improve the dry matter digestibility of low quality roughage. It was found that percent improvement in feed intake for the physico-chemical treatment (51.20 was much higher than biological (40.8%), physical (32.5%) or chemical (31.0%) treatments. Physical (84.4%), chemical (84.9%), physico-chemical (51.5%) and biological (148.4%) treatments of crop residues had a more striking effect on the percent improvement in performances of ruminant animals than on the percent improvement in DM digestibility or feed intake. Supplementation (physical), sodium hydroxide, ammonia, urea/urine (chemical), silage and/or manure·silage (biological) treatments were the most practical and beneficial ways to improve the nutritive value of crop residues. Effects of various treatments on the chemical composition, digestibilities, characteristics of cell walls, feed intake, VFA production, ruminal pH, performance of animals and feed cost are summariz
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
