Chemical Treatment of Crop Residues

https://idl-bnc.idrc.ca/dspace/bitstream/10625/8776/3/70328.pdf

Rice straw as a feed for ruminants

Chopped wheat straw, containing increasing amounts of added water was treated with a constant level of ammonia (33 percent of straw dry matter) as ammonium hydroxide, and stored for I to 60 days before determing in vitro dry matter digestibility (IVD MD), nitrogen content and fiber-bound nitrogen (ADF-N) versus free ammonia nitrogen (NH3N) of the treated sample The overall improvement (eg, mean of all day X moisture treatment combinations) in IVDMD of treated versus untreated straw was about 33 percent, whereas nitrogen content of treated straw was increased from 46 percent crude protein to 110 percent crude protein Fiber-bound nitrogen and NH3N accounted for 126 and 434 percent of the retained nitrogen, respectively, when averaged across all day X moisture treatment combinations The ammonium hydroxide treatment increased straw digestibility by (I) directly decreasing the total cell wall fiber (NDF) and hemicellulose fractions (perhaps by solubilization effects), and (2) increasing the digestibility of the NDF, hemicellulose and cellulose fiber fractions

/pdf/ammonium-hydroxide-treatment-on-wheat-straw-3523pb1awu.pdf

Ammonium Hydroxide Treatment on Wheat Straw

The effect on digestibility of a new technique for alkali treatment of straw

Historically, many fibrous and by-product feedstuffs have been overlooked, particularly by U.S. livestock producers, as potential alternative energy sources for ruminants. As the demand for direct human use of cereal grains increases, however, these feedstuffs will be used increasingly in the ruminant livestock production enterprise. Greenhalgh (1984) identified four reasons for the resurgence in interest in the feeding of agricultural residues: (i) new feeding strategies for ruminants that involve fibrous residues; (ii) more pre­ cise knowledge of animal nutrient requirements, resulting in the identifica­ tion of situations where less than maximal nutrition is required; (iii) better supplementation regimens that optimize ruminal digestion and postruminal utilization of nutrients; and (iv) new methods for improving the nutritive value of fibrous feedstuffs themselves. In addition, changing agricultural strategies, future political realities, and continuing research to understand and overcome the barriers to microbial fermentation of lignocellulosics may increase the attractiveness of crop residues as feeds for ruminants. Current trends toward sustainable agriculture, with its emphasis on decreased reli­ ance on fertilizer, herbicides, and pesticides, may result in lower U.S. yields of cereal grains. Cereal grains for livestock production therefore may increase in cost because of decreased availability. Additionally, international pres­ sure exists to reduce the disparity in standard of living between developed and underdeveloped countries and may help to redistribute food resources. As a result, cereal grains may become less available to livestock producers in developed countries. Finally, steady progress in understanding and over­ coming the barriers to microbial fermentation of lignocellulosics, particu­ larly through chemical treatments, has greatly improved the feeding value of crop residues. Agricultural residues are in plentiful supply. Approximately 1 kg of residue is produced for each kilogram of grain harvested. This ratio of grain/residue translates into an excess of 400 Tg of crop residue produced

Postharvest Treatment of Fibrous Feedstuffs to Improve Their Nutritive Value

Summary A LFALFA stems, corn cobs, whole corn plant and corn stalks were treated with sodium hydroxide or peroxides and fed to lambs in digestion and metabolism trials. The dry roughages were mixed with the chemicals and enough water to increase the moisture to 50%. The materials were fed after a 48-hr. reaction period or after ensiling. Four percent NaOH treatment increased the dry matter digestibility of alfalfa stems by 6.8 percentage units. Corn cob dry matter digestibility in- creased by 11.2 percentage units due to 4% NaOH treatment. In vitro DMD of whole corn plant increased 9.7 percentage units but in vivo 'organic matter digestibility increased by only 2.5 percentage units. In vitro DMD of corn stalks increased 12.8 and 19.5 per= centage units, respectively, with 3 and 5% NaOH treatment. In vivo organic matter di- gestibility of corn stalks increased 10.1 and 11.2 percentage units, respectively, for 3 and 5% NaOH treatment when fed supplemented only with urea, minerals and vitamins. The five percent NaOH treated stalks showed a 20.5 percentage unit increase in organic mat- ter digestibility compared to untreated stalks when both were fed in combination with ground alfalfa stems. These results indicate that poor quality roughages can be treated with 3 to 5% NaOH, the moist mixture after ensiling is consumed readily by lambs without further treatment, and that the dry matter digestibility is increased by sufficient magni- tude to potentially improve animal perfor- mance. Introduction Low quality roughages are inefficiently util- ized by ruminants because of high content and poor digestibility of the fibrous fractions. This poor digestibility is related to the extent of

M. J. Jones

Papers

Chemical Treatment of Low Quality Roughages