• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.314-319
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• 2015

Purpose: The ratio of straw to grain mass as a function of cutting height affects combine efficiency and power consumption and is an important input parameter to combine simulation models. An equation was developed to predict straw to grain ratios for wheat as a function of cutting height. Methods: Two mass functions, one for straw and one for grain, were developed using regression techniques and measured data collected in west Texas during the summer, and used to predict the straw to grain ratio. Results: Three equations were developed to facilitate the simulation of a combine during wheat harvest. Two mass functions, one for straw and one for grain, were also developed; a quadratic equation describes the straw mass with an $R^2$ of 0.992. An S-shaped curve describes the mass function for grain with an $R^2$ of 0.957. An equation for straw to grain ratio of wheat was developed as a function of cutting height. The straw to grain ratio has an $R^2$ value of 0.947. Conclusions: In all cases, the equations had $R^2$ values above 0.94 and were significant at the 99.9 percent probability level (alpha = 0.001). Although all three equations are useful, the grain mass and straw to grain ratio equations will have direct application in combine simulation models.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.413-419
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• 1994

Mold growth decreased nutritive value of wheat straw (WS). Mold increased DM (94 vs 98%) and ADF (51 vs 56%) contents and had no effect on natural detergent fiber (NDF). Crude protein and N values were decreased in moldy wheat straw, Mold increased insoluble N content of wheat straw (WS) from 21 to 27%. Ammoniation increased the CP of nonmoldy straw from 3.8 to 8.3% and moldy straw from (3.3 to 6.2%). Aspergillus and zygomycetes fungal species were most prevalent and total numbers were higher on moldy straw. Ammoniation decreased total numbers of fungal spores on nonmoldy and moldy WS. Ammoniation of moldy WS increased (p < 0.10) feed in take (1.8%) as compared with nonmoldy, ammoniated, nonmoldy and moldy WS. Steers fed moldy WS had lowest (p < 0.10) feed intake (1.3% of BW daily) compared with other diet. There was little difference (p < 0.10) in intake of nonammoniated vs. ammoniated WS. Steers fed moldy straw lost 6 kg BW. Ammoniated, nonmoldy straw elevated Blood Urea Nitrogen (BUN) (10.5 mg/dl). Alkaline Phosphatase (ALK) was greater in steers fed moldy VS nonmoldy straw (148 VS 95 U/liter. p < 0.10).

• Journal of Mushroom
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• v.8 no.1
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• pp.33-36
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• 2010

The effect of wheat straw mix was tested to develop rice straw replacement media. The chemical contents were analysed after late fermentation. Nitrogen content and C/N ratio of the 20% wheat straw mixing medium were 2.2% and 16.7 and the only rice straw using medium were 2.0% and 17.9, respectively. When the 20% wheat straw mixing treatment was compared to the only rice straw medium, pinhead initiation period was shortened and the yield was increased as much as 30%. Therefore the 20% wheat straw mixing medium is expected to replace the rice straw medium.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.4
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• pp.213-218
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• 1988

Forty eight growing bulls of two breed types(red Sahiwal and white Kilari), fed rice straw, were allocated to nine treatment groups: 1. Control straw (CS) 2. Urea upgraded straw (UUS) 3. UUS + 0.25 kg coconut cake (CC) 4. UUS + 0.75 kg CC 5. UUS + 0.25 kg rice bran (RB) 6. UUS + 1.00 kg RB 7. UUS + 0.25 kg RB + 0.25 kg CC 8. UUS + 1.00 kg RB + 0.25 kg CC 9. CS + 1.00 kg RB + 0.25 kg CC Liveweight gain was measured weekly during 15 weeks and tested in three analyses of variance. The results are: Urea upgraded straw produced a liveweight gain $180g.d^{-1}$ higher (P <0.01) than control straw. The groups supplemented with 0.25 kg coconut cake and 1.00 kg rice bran showed an increase of $100g.d^{-1}$ (p < 0.05) over the unsupplemented groups. No interaction between straw upgrading and supplementation was present (P > 0.10). Both rice bran and coconut press cake, supplemented to upgraded straw at a level of 0.25 kg, did not increase liveweight gain (P>0.05), but 1.0 kg rice bran increased gain by $90g.d^{-1}$ (P<0.05). A supplement of 0.75 kg coconut press cake to upgraded straw increased liveweight gain by $160g.d^{-1}$ compared with 0.25 kg or 0.00 kg coconut cake supplement (P<0.05). There were no significant differences between breed types (P>0.10) or interactions between breed and the other two main treatments (upgrading and supplementation). It was concluded. that both urea upgrading and supplementation of rice straw increase animal performance. The effect of urea upgrading was the same for both supplemented and unsupplemented animals. There was no indication of a nonlinear effect of supplements on growth.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.436-443
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• 2012

This research was focused on the effect of rice straw and rice straw mat on the reduction of upland field non-point source (NPS) pollution discharges. Six experimental plots of $5{\times}22m$ in size and 3% in slope prepared on gravelly sandy loam soil were treated with control, rice straw cover and rice straw mat cover. Radish in Spring growing seasons were cultivated. NPS pollution discharge was monitored and compared with respect to the treatments. The surface cover rate of rice straw and rice straw mat right after the treatments was 64.7% and 73.7%, respectively. Rainfall of the 16 monitored events ranged from 12.8 mm to 538.2 mm. Runoff coefficient of the events was 0.01~0.67 in control plot, 0~0.63 in rice straw plot and 0~0.45 in rice straw mat plot. The reduction of runoff compared to the control plot was 5.4~99.7% in rice straw plot and 32.9~100% in rice straw mat plot. The reduction of NPS pollution load was 52.0% for SS, 28.5% for T-N and 35.2% for T-P in rice straw plot and 79.8% for SS, 68.3% for T-N and 53.3% for T-P in rice straw mat plot. This research revealed that rice straw mat cover on the soil surface could not only increase the crop yield and farmer's income but also reduce the NPS pollution loads significantly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.132-136
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• 2002

The rice straw managements are essential for maintaining soil fertility as well as reducing chemical fertilizer application in paddy field. A field experiment was conducted on moderately well draining alluvial paddy soil to investigate the decomposition pattern of rice straw. The mesh bags containing the rice straw harvested in the previous year were placed at soil surface and buried into around 10cm depth and recovered periodically for determining the straw decomposition. Pot experiments were conducted to investigate the fates of N released from $^{15}$ N-labeled rice straw under different levels of N fertilizer application. The overall decomposition patterns of rice straw were similar for the two incorporation depths in transplanted paddy field. The straw incorporated at transplanting date showed weight loss of about 50%, 70% and 90% after 2 months, 5 months, and 2 years, respectively. The decompositions of straw cell wall components showed somewhat different pattern. The decompositions of cellulose and silica were similar to that of dry weight while the decomposition of lignin was slower than that of cellulose and silica. N was released from rice straw 42% and 65 % of the initial N after one month and after five months, respectively. P release was faster than N release. Recoveries of rice straw-$^{15}$ N by rice plants were 10.2, 13.4 and 14.9% in 0, 120 and 240 mg N pot$^{-1}$ , respectively. Soil recoveries of rice straw $^{15}$ N were 17.3, 20.6 and 18.9% in 0, 120 and 240mg N pot$^{-1}$ , respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.4
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• pp.493-498
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• 1994

The response of crossbred Holstein milking cows to the neutralized urea-treated rice straw feeding was investigated. Rice straw was treated with 6% urea for at least 21 days and further with sulfuric acid for overnight to complete the neutralization. The neutralized straw was then sun-dried and its feeding value was compared with that of the dried non-neutralized urea-treated straw. They were fed to the cows with concentrates either by the ration formulation based on the nutrient requirements for milk production recommended by NRC or by the traditional way in which straw was fed ad libitum and concentrates at 1 kg/2 kg of milk production. The results showed that milk production as well as milk composition of cows were not different between neutralized and non-neutralized straw. The feeding of the neutralized straw could significantly reduce the supply of protein-rich feed such as soybean oil meal, and it was demonstrated that ammonium sulfate in the neutralized straw could be utilized as effective as the plant origin protein. The results also suggested that if the traditional feeding method is applied to the dairy cattle, protein content of the supplementing concentrates should be increased to meet the requirement.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.1
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• pp.1-5
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• 1988

Ninety feeder steers, predominantly Herefords weighing 280 kg, were assigned at random to each of nine diets: basal (high concentrate); 25 or 50% of untreated rice straw (25- or 50 URS) or ammoniated rice straw (25- or 50 ARS); a 50:50 mixture of URS - alfalfa or ARS - alfalfa replacing a proportion of the basal at 25 and 50%. Animals were slaughtered after 154 or 161 days of feeding. The cattle fed 50% URS had the lowest (P<.05) carcass weight, dressing & external fat thickness, kidney, pelvic and heart fat, rib eye area, marbling score, quality and yield grades, followed by cattle fed 50% ARS, 50% rice straw/alfalfa, and 25% rice straw alone or 25% rice straw/alfalfa mixture. Ammoniation of rice straw improved all measured traits. A 25% substitution of basal diet with untreated or ammoniated rice straw and a 50% substitution with rice straw/alfalfa mixture did not significantly affect carcass traits compared to the basal group. Only 50% ARS and 50% URS cattle showed differences in body composition (P<.05) with lower fat and higher water and protein contents. No significant differences were found in shear value, panel tenderness, connective tissue, juiciness, flavor and overall palatability of meat from steers fed the basal, ARS or URS diets.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.845-851
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• 2006

Spent compost wheat straw is an available by-product from edible mushroom production, which constitutes a potential pollutant and is cost effective for disposal. This study was conducted to determine the nutritive value as ruminant feed of spent wheat straw compost from Agaricus bisporus mushroom production. The compost was provided from a mushroom farm, the casing soil was removed from the whole compost, and then it was sun dried and sampled for chemical analysis. An experiment was conducted, in which four wheat straw-based diets comprising control (I), 10% spent straw (II), 20% spent straw (III) and 30% spent straw (IV) were tested in a cross-over design using 8 sheep. Dry matter intake (DMI) was 74.0, 73.8, 70.2 and 57.1 and organic matter intake (OMI) was 62.7, 63.4, 58.0 and 44.4 g per kg $BW^{0.75}$ for diets I, II, III and IV, respectively, which, were significantly (p<0.05) lower for diet IV. Digestible OMI was respectively 33.1, 32.6, 30.6 and, 20.2 g per kg $BW^{0.75}$ on the four diets which were significantly (p<0.05) different between the treatments. Inclusion of spent compost straw up to 20% of the diet did not affect the digestibility of DM, OM, CF, ADF and NDF, but the diet containing 30% compost straw had statistically (p<0.05) lower digestibilities. Nitrogen balance was also significantly (p<0.05) different between the treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.329-335
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• 1992

Degradation of rice straw was observed to be higher (p<0.01) in the buffaloes than in cattle. At 48 h, the dry matter (DM) loss of straw for buffaloes was 53.6 0.8% and that for cattle was 48.7 2.6%. Palm press fibre (PPF) was poorly degraded in the rumen of both animal species. A loss of about 21% DM was observed in both cattle and buffaloes after 48 h of incubation in the rumen. The pattern of bacterial and fungal colonization of straw and PPF seemed to be similar in both cattle and buffaloes. Microbial colonization was restricted by plant structures like the silica crystals in both straw and PPF. The predominant bacteria colonizing both straw and PPF fragments were the rods. Eroded zones and digestion pits were pronounced in straw fragments after 1 h of incubation. The PPF fragments appeared undegraded even after 6 h of incubation. Fungal colonization of straw was rapid and extensive in both cattle and buffaloes. The sporangia observed in straw were mainly spherical or oval in shape, but fusiform sporangia with acuminate tip were predominantly seen in PPF fragments.