Treated Wheat Straw Research Articles

Commercial experience of treating straw with ammonia

Paired samples of barley (118), wheat (31) and oat (4) straw, either untreated or treated with ammonia, showed improvements in digestible organic matter in vitro from 46 to 54, 44 to 54 and 46 to 57%, respectively. The improvement in straw (66 paired samples) treated with aqueous ammonia in a stack was 7.8 ± 4.7 units, but it was 12.4 ± 4.5 units when treated with anhydrous ammonia (20 samples). This was similar to an improvement of 11.7 ± 4.9 when straw was treated with anhydrous ammonia in an oven (67 samples). There was no significant influence of moisture content and samples with the lowest initial digestibility showed the greatest improvement after treatment. The majority (68%) of the 213 farms studied had treated barley straw and 18% had treated wheat straw. About 60% of stack-treated straw was given to store stock compared with only 39% of that treated in an oven, and only 4% of the total treated straw was given to sheep. Just over 50% of farmers treating straw in a stack were pleased with the results, but 25% stated that they would not continue the treatment another year. Of those who treated straw in an oven, 85% were pleased and most of these farmers intended to treat for another year. The results are discussed in the broader context of the probable impact of the system.

Enzymatic hydrolysis of agricultural residues by Trichoderma cellulases and the fermentation of the liberated sugars to ethanol

Five different agricultural residues, barley straw, wheat straw, corn stover, corn stalks and alfalfa stalks were pretreated by steam explosion. The pretreated agricultural residues were then hydrolyzed by the addition of 15 IU of Trichoderma E58 cellulase per gram dry weight of residue. This resulted in the hydrolysis of 46% of the barley straw, 42% of the wheat straw, 38% of the corn stover and corn stalks and 31% of the alfalfa stalks, to reducing sugars after 24 hrs incubation. Water washing the steam treated wheat straw increased the percent hydrolysis of cellulose to glucose from 18% to 35%. When the agricultural residues were fermented to ethanol using a combined hydrolysis and fermentation procedure, the efficiency of hydrolysis was further improved by 8% to 19%, depending on the nature of the substrate.

Utilization of low quality roughages: effects of alkali treatment of wheat straw on intake by and growth rate of cattle, with and without a supplement of cotton-seed meal

SUMMARYEffects of treating wheat straw with caustic soda solution and of providing a cottonseed meal supplement were studied with 40 Friesian heifers (280 kg live weight) in individual pens. Responses were measured in terms of food intake, growth rate and food conversion ratio.Wheat straw was coarsely-milled and fedad libitum, untreated (U) or alkali-treated (T); both types of straw were supplemented with urea and minerals. Half the animals on each type of straw were fed 500 g cotton-seed meal (C/day.Straw intake was higher with T than with U (P< 0·01) and unaffected by the cotton-seed meal supplement, being 4·53, 4·71, 6·58 and 6·56 kg/day on treatments U, UC, T and TC respectively. Alkali treatment and the cotton-seed meal supplement improved live-weight change (P< 0·001), being –6, 189, 334 and 495 g/day respectively.In vivodigestible organic matter in the dry matter, calculated from lignin ratios, was 59, 60, 64 and 64 respectively.Rumen VFA concentrations were significantly higher, molar proportions of acetic acid lower, propionic andn-butyrie acids higher in animals on T than on U. Plasma urea and rumen ammonia concentrations were lower on treatment T than on U.It was concluded that wheat straw which is coarsely-milled, NaOH-treated and sprayed with urea and minerals provides sufficient nutrients to allow cattle to grow and that additional gain obtained by feeding cotton-seed meal was predictable in terms of its energy contribution to the diet.

Performance of fattening cattle and lactating beef cows on diets high in chemically treated wheat straw and poultry litter

Three experiments were carried out to study the effect of chemical treatment on the nutritive value of wheat straw (WS) and the effect of diets containing such treated straw and poultry litter (PL) on the performance of fattening cattle and lactating beef cows. The chemical treatment consisted of treating half of the wheat straw with 60 kg sodium hydroxide/t and the other with 60 kg sulphuric acid/t, and then mixing the two to give “Celephos”. The digestibility coefficient of organic matter was 68.0 and 41.7 for “Celephos” and untreated straw, respectively. For a long term feeding trial, two mixtures were formulated: (a) including 23% WS and 19% PL; (b) including 30% chemically treated WS and 16% PL. A conventional high grain fattening diet (c) served as control. The metabolizable energy concentrations in the above diets were 2.37, 2.38 and 2.78 Mcal/kg DM. Protein content of the diets was regulated by PL or soya bean meal. Liveweight gain was 1059, 1137 and 1180 g/day, metabolizable energy conversion ratio to liveweight was 22.8, 20.7 and 20.0 Mcal/kg, and carcass gain was 565, 606 and 656 g/day for treatment groups (a), (b) and (c), respectively. In a third trial, lactating beef cows were fed on long straw or Celephos, PL and 1.5 kg grain per head per day. Intake of Celephos was 28% higher than that of untreated straw and milk output was 3 kg/day higher. This was reflected in an increase of 67 g/day in gain of suckled calves.

Wheat Straw in Growing Cattle Diets

Summary Three cattle growth trials were conducted to evaluate the use of untreated and alkali-treated wheat straw as energy sources for ruminants. In trial 1, daily gain decreased as level of untreated wheat straw increased in the diet. A 14% decrease in gain occurred when the level of straw was increased from 30 to 40% of the diet. In trial 2, cattle fed 4% NaOH-treated wheat straw at the 30 or 60% level had better daily gains and feed efficieneies (P<.05) than those fed untreated wheat straw. In trial 3, when the effect of balancing for specific mineral ratios on the alkali-treated straw diets was evaluated, steers fed 78% treated wheat straw with added minerals gained faster (P<.05) than those receiving 80% treated wheat straw with no mineral additions (.65 kg/day vs..54 kg/day). In addition, in this trial, cattle fed 50% treated wheat straw gained faster (P<.05) than those fed 50% untreated wheat straw (.74 kg/day vs. .62 kg/day).

Chemical Treatment of Wheat Straw

Summary An in vitro digestion study, a lamb growth trial and a lamb digestion trial were conducted to evaluate the effect of different NaOH and Ca(OH)2 treatments on the energy availability of wheat straw. In vitro dry matter disappearance (IVDMD) of wheat straw was increased 29% by chemical treatment with 1% NaOH plus 3% Ca(OH)2 and by as much as 86% by a 4% NaOH plus 1% Ca(OH)2 treatment. A significant amount of hemicellulose was solubilized by chemical treatment with NaOH and Ca(OH)2, but little cellulose was solubilized. Rate and extent of both hemicellulose and cellulose digestion of treated wheat straw were increased significantly in comparison to corresponding measures for untreated wheat straw. Lambs fed chemically-treated wheat straw gained significantly faster and more efficiently and consumed more dry matter per day than those fed untreated wheat straw diets. Chemical treatment of wheat straw significantly increased dry matter, organic matter cellulose and hemicellulose digestibilities in the lamb digestion trial. Organic matter digestibility was increased from 51.3% for untreated wheat straw to 65.3% for 4% NaOH-treated wheat straw.

Retention of Organic Matter and Nitrogen by the Silt and Clay Fractions and by the Whole Soil as Affected by Lime and Organic Residues

AbstractThe experiment was conducted in glazed 3‐gallon pots in the greenhouse, using Kirvin clay soil, limed and not limed, treated with red clover, wheat straw, and Juniper wood residues. An application of 59.5 mg. of nitrogen per 100 g. of soil was made at the beginning, and again after 15 months. Soil samples were taken from each treatment before planting the first crop, after 15 months, and again after 48 months. Ten crops were grown during the 4‐year period.There was a marked loss of nitrogen from all soils during the experiment, but loss from limed soil was greater than from unlimed soil. The highly carbonaceous materials retarded nitrogen loss. There was a tendency for nitrogen to accumulate in the silt fraction, especially in unlimed soil.The amount of organic matter retained by the soil was not affected by lime content and there was no difference in organic matter and total nitrogen contents of the wheat straw and red clover treatments after 48 months, although the organic matter/nitrogen ratio was 21.0 for the red clover treatment and 34.4 for the wheat straw treatment when the experiment started.Only the Juniper wood had a significant effect on aggregate stability after 48 months.