Untreated Barley Straw Research Articles

Effect of hydrogen peroxide‐dependent enzyme systems on the in‐vitro digestibility of untreated and ammonia‐treated barley straws

AbstractA series of small‐scale in vitro experiments was conducted to evaluate the effectiveness of various hydrogen peroxide (H2O2)‐dependent enzyme systems, peroxidase and glucose oxidase, in improving the nutritive value of ammonia‐treated and untreated barley straw. H2O2 and peroxidase increased (P≤0.001) digestibilities when used individually, but their combined use did not influence digestibility significantly (P>0.05). The effect of H2O2 alone was greater than that of peroxidase alone. The combination of glucose and glucose oxidase to generate H2O2 produced a small but non‐significant (P>0.05) increase in the digestibility of straw. The combination of glucose oxidase and peroxidase was ineffective in improving digestibility of straw. The digestibility values of ammonia‐treated barley straw were always greater (P≤0.001) than those of untreated straw but none of the treatments showed any interaction with ammonia treatment. It is suggested that H2O2 treatment improves the digestibility of straw.

Factors affecting degradation of barley straw in sacco and microbial activity in the rumen of cows fed fibre-rich diets. I. The source of supplemental nitrogen

Untreated barley straw was incubated in nylon bags for up to 72 h in the rumen of three non-lactating dairy cows fed restricted amounts of a diet composed of 76% untreated barley straw and 24% grass hay, and supplemented with urea, casein, soybean meal or fishmeal to make the ration up to 12% protein. The experiment followed an incomplete balanced block design. Fishmeal produced the highest degradability of dry matter, organic matter, cellulose, hemicellulose and individual sugars. For most components of the barley straw, urea produced the lowest results. The source of nitrogen also affected rumen pH, ammonia and volatile fatty acid concentrations, but had no effect upon rumen outflow rate of liquid or particulate phases. Microbial activity was higher in fishmeal and soybean meal than in urea and casein and highest in fishmeal in the residue after extraction of most of the rumen liquid, suggesting that fishmeal exerts its effect upon microbes intimately associated with the fibre and not upon the whole bacterial population. Microbial activity and biomass within the nylon bags were never constant but related to processes of colonization and depletion of degradable substrate.

Carbohydrate and nitrogen metabolism in the forestomach of steers given untreated or ammonia treated barley straw diets supplemented with urea or urea plus fishmeal

Four protozoa-free steers were given diets consisting of a concentrate mixture of flaked maize plus tapioca with either chaffed untreated barley straw (US) or chaffed ammonia treated barley straw (AS). The diets were supplemented with urea (USU; ASU) or urea plus fishmeal (USF; ASF). The diets were calculated to be isoenergetic and given in amounts calculated to provide sufficient metabolisable energy (ME) to support a growth rate of 0.5 kg day −1 in a 4 × 4 Latin square arrangement. Both diets were also calculated to be isonitrogenous with respect to rumen degradable protein (RDP). Chromic oxide and polyethylene glycol were given as digesta flow markers and ribonucleic acid (RNA) and 35S were used as microbial markers. Flows (g per 24 h) at the abomasum of nitrogenous constituents and carbohydrate components were determined. Rumen pH was consistently lower and rumen ammonia concentrations were higher with urea plus fishmeal supplemented diets (USF, ASF) than with urea supplemented diets (USU, ASU). No significant differences were observed in either parameter between treated and untreated straws, however supplemented. Non-ammonia nitrogen flows at the abomasum were significantly higher with fishmeal supplemented diets than with urea supplemented diets but there were no significant differences relating to straw treatment. Microbial nitrogen flows at the abomasum were not significantly different between diets and averaged 37 g day −1. Efficiencies of microbial protein synthesis were not significantly different between diets and averaged 23 g N kg −1 apparently digested organic matter (ADOM), 18 g N kg −1, truly digested organic matter (TDOM) and 24 g N kg −1 total carbohydrate fermented. Total feed nitrogen degradabilities between the mouth and abomasum were 0.84, 0.69, 0.85 and 0.68 for diets USU, USF, ASU and ASF, respectively. Nitrogen degradability values of the basal straw plus concentrate components were 0.53 and 0.57 for diets US and AS, respectively. Degradability of fishmeal nitrogen was 0.43 and 0.38 for diets US and AS, respectively. Digestibility coefficients for the main structural sugars arabinose, xylose and cellulose-glucose were 0.60, 0.53 and 0.59, respectively, for diet USU. The corresponding values for diet ASU of 0.71, 0.62 and 0.66 were all significantly ( P < 0.05) higher. Fishmeal supplementation significantly enhanced ( P < 0.05) the digestibilities of the structural sugars with both types of straw.

Effect of NaOH dip-treatment on intake, digestibility and selection of previously-refused straw by goats

Wahed and Owen (1986) showed that increasing the amount of straw offered to allow refusal rates of 50% instead of the conventional 20% increased straw dry matter/digestible organic matter intake by 40%. Feeding generously to allow selective feeding was suggested as an alternative to alkali treatment of straw. Such a feeding strategy would be useful to farmers in developing countries where the cost of alkali treatment of straw is high. However the strategy generates large amounts of refusals. Unless refused straw can be utilised for other purposes, feeding at such generous levels will not be acceptable. This study was carried out to establish whether refused straw, if treated with alkali, can be re-fed to goats.Twelve Saanen-type castrated goats aged 18-24 months were used in a change-over design experiment. Goats were housed in individual metabolism crates and fed one of the following:1.Untreated barley straw (S) offered in quantities to allow goats to refuse 50% of the amount offered.2.Untreated previously-refused-straw (RS) offered in quantities to allow refusal of 25% of the amount offered.3.NaOH dip-treated previously-refused-straw (DRS) offered in quantities to allow refusal of 25% of the amount offered.

Effect of rates of offer and treatment with sodium hydroxide or ammonia on intake, digestibility and selection of barley straw by goats

Wahed and Owen (1986) showed that intake of untreated barley straw increased by up to 40% when the amount offered was increased to allow goats to refuse 50% of the amount offered instead of the 15-20% used in conventional ad libitum intake trials. The increase was attributed to greater opportunity to select the more digestible parts of the straw. The present experiment was made to see whether similar responses occur if digestibility of the straw is increased by alkali treatment.Thirty-six individually-fed Saanen-type castrates weighing 31-65 kg were used in a 3x2 (3 straw types, 2 rates of offer) factorial design experiment. Goats were blocked according to weight (M) and allocated randomly within block to one of 6 treatments. They were offered untreated barley (var. Triumph) straw (S), ammoniated barley straw (NH3-S) or NaOH-dip-treated barley straw (NaOH-S) at either 20 g DM per g M daily (L) or 50 g DM/kg M.d (H). Straw was ammoniated on 25th August 1987 by the Stack Method (Sundstol and Coxworth, 1984) using aqueous ammonia (35 g NH3/kg straw DM). The stack was opened 30 days later. NaOH-dip-treatment (Sundstol, 1981) involved dipping in a solution containing 15 g/kg NaOH and 7 g/kg urea. Straw was dipped daily and allowed to mature 3-4 d before feeding. Goats were supplemented with concentrates (g/kg DM: milled barley, 600; soya bean meal, 180; fish meal, 180; mineral mix, 40) at 18 g DM/kgM 0.75.d. They were fed twice daily (0800 and 1600 h), offered water ad libitum and individually penned with sawdust bedding.

Calf performance as affected by the quality of grass hay and its substitution by untreated or ammonia-treated barley straw

Calf performance as affected by the quality of grass hay and its substitution by untreated or ammonia-treated barley straw

Fibre degradation in the rumens of animals receiving hay, untreated or ammonia-treated straw

The rate and extent of degradation of the dry matter of untreated barley straw (US), ammoniatreated barley straw (AS) and hay (H), when incubated in nylon bags in the rumen, was studied in rumen-cannulated adult sheep. Three different rumen conditions were created by feeding US, AS and H to the sheep. The three roughages were adequately supplemented with urea, sodium sulphate, vitamins and minerals. In addition to degradation studies, the rumen NH 3 and rumen pH were measured and microbial colonisation of fibre was studied by electron microscopy. The extent of degradation of US was found to be significantly higher in animals given either AS ( P < 0.001) or H ( P < 0.02) to eat than in those given US. Electron microscopy showed that bacterial colonisation of US fibre differed qualitatively and quantitatively among the animals given the three different roughages. Straw fibre incubated in the rumens of animals given AS had the highest number of bacteria attached to it. The stimulatory effects of the readily digestible cellulose and hemicellulose of AS on the microbial density and colonisation characteristics of fibre-degrading microflora are discussed.

The effect of five different supplements on the degradation of straw in sheep given untreated barley straw

Five experiments were conducted to investigate the dietary factors within the rumen environment which could contribute to changes in the degradation of barley straw. Degradation was measured by recording the losses of dry matter (DM) from samples of straw incubated in nylon bags in the rumen for various periods of time. Three sources of supplementary energy (sugar-beet pulp, citrus pulp and dried grass) and two sources of protein (soya-bean meal and fish meal) were investigated for their ability to increase degradation of straw when given as supplements to untreated straw. The untreated straw used in these experiments was adequately supplemented with rumen-degradable nitrogen, sulphur, vitamins and minerals. Unmolassed sugar-beet pulp and dried grass, when given at a level of 150 g kg −1 straw DM, increased both the rate and extent of degradation of straw DM. Citrus pulp and soya-bean meal had no effect on the degradation of straw, while fish meal appeared to have a small effect. It was concluded that in particular digestible cellulose and/or hemicellulose improved the conditions in the rumen for straw fibre degradation in animals given straw diets.

The influence of anaerobic fungi on rumen volatile fatty acid concentrationsin vivo

SummaryElimination of the rumen anaerobic fungi from sheep fed chemically-treated barley straw diets resulted in elevated proportions of propionic acid in rumen liquor (fromca. 0·15 to 0·30). Subsequent inoculation of these sheep with a pure culture of fungus decreased propionate concentrations within 3 days to the levels observed in control animals that possessed abundant fungal populations throughout the experiment.Confirmation that propionate itself was not responsible for the elimination of the fungi was provided by the results of a second experiment in which intraruminal infusions of propionic acid failed to reduce fungal growth or prevent recolonization in sheep previously rendered fungi-free.In a third experiment with sheep fed untreated barley straw, monensin supplementation produced the well known elevation of propionate concentrations. However, this treatment also resulted in the elimination of rumen anaerobic fungi from the animals. The magnitude of the increased concentration of rumen propionic acid, resulting from the elimination of the anaerobic fungal flora, indicates an important role for the fungi in the fermentation of high-fibre diets. In addition, these findings indicate that the well known elevation of propionate levels produced by monensin may likewise be effected directly by removal of the rumen anaerobic fungi.

Effect of amount offered on selection and intake of long untreated barley straw by goats

Effect of amount offered on selection and intake of long untreated barley straw by goats

Rumen degradation of straw 1. Untreated and ammonia-treated barley, oat and wheat straw varieties and triticale straw

ABSTRACTThe dry-matter degradation of 19 varieties of barley, 14 varieties of wheat, 11 varieties of oats and one variety of triticale straws, both untreated and ammonia treated were studied using the nylon-bag technique. There were significant differences between the untreated varieties of all the types of cereal straw studied with respect to dry-matter loss (DML) values. When the barley and wheat straws were treated with ammonia, the differences between the varieties were also significant although ammonia treatment tended to improve those with lower values to a greater extent than those with higher values. There were also significant differences between the DML values of the oat straws when they were treated with ammonia but only after 48-h incubation. There was a significant negative relationship between the 48-h DML values of the untreated oat straws and the improvement in the DML values with ammonia treatment (r = −0·65; P &lt; 0·05). Grain yield, straw length and nitrogen concentration had no significant relationship with the DML values of the untreated straws. Barley and oat straws had generally higher DML than the wheat and triticale straws.

The effects on growth, food intake and rumen volume of including untreated or ammonia-treated barley straw in a complete diet for weaning calves

ABSTRACTTwo experiments were conducted using British Friesian bull calves to determine the effects on growth, food intake and rumen volume of including 0, 150, 200 or 250 g ammonia-treated (35 g/kg dry matter (DM)) or untreated barley straw per kg pelleted concentrate based on cereal. All calves received once daily 440 g milk replacer powder reconstituted in 3 1 warm water, were weaned at 56 days of age and given one of the seven pelleted diets to appetite from 14 days of age. In experiment 1, the seven diets were allocated at random to 70 calves. Food intake was increased by the inclusion of straw but there was no effect on intake of the increased concentration of straw; daily DM intake from 14 to 77 days of age was 1·36 and 1·77 kg/day respectively for diets with or without straw. From 14 to 56 days of age intake of concentrate was increased by the addition of straw but was negatively correlated with the concentration of straw in the diet. After weaning inclusion of straw, whilst increasing total intake, tended to depress intake of cereal. Treatment with ammonia increased the nitrogen concentration in the straw but had no effect on the digestibility or amount of diet consumed. After adjustment was made for gut fill, the increases in weight between 4 and 84 days of age of calves given 150, 200 or 250 g straw per kg food were 6·6, 1·2 and 1·0 kg respectively greater than those that occurred when there was no straw in the diet. DM digestibility of all diets was above 0·67 but the mean digestibility of acid detergent fibre was low (0·19). The pH and ammonia concentration of rumen liquor were low and below the optimum for cellulose digestion. In experiment 2, rumen volume was measured in vivo in a group of 24 calves given the same diets as in experiment 1. Rumen volume was increased two fold at 42 days of age by the addition of straw to the diet (5·6v.2·6 1,P&lt; 0·001), by 87 days of age the difference was increased to 7·11, (19·0v.11·9 1,P&lt; 0·01). When all calves were given the same diet from 91 days of age, there was no effect of previous treatment on intake or rumen volume at 147 days of age.

Evaluation of detergent extraction procedures for characterising carbohydrate components in ruminant feeds and digesta

AbstractSteers fitted with simple rumen and abomasal cannulas were given isoenergetic diets of approximately equal amounts of untreated (UT) barley straw and concentrates (flaked maize + tapioca) alone (BS) or with urea (BSU) or fishmeal (BSF). Similar diets were also given in which the barley straw had been treated (AT) with NaOH (BSA, BSAU and BSAF respectively). The diets were given in a 6 × 6 Latin square design. Feed components and abomasal digesta samples were analysed for neutral (NDF) and acid (ADF) detergent fibres and for monosaccharide constituents of structural polysaccharides. Hemicellulose contents were estimated as the sum of xylose + arabinose (X + A) and by the difference between ash‐free NDF and ash‐free ADF (NDF‐ADF). Cellulose was estimated as β‐linked glucose (C) and by the difference between ash‐free ADF and lignin (ADF–L).103 Ruthenium and PEG were given as flow markers and flows (g24h−1) at the abomasum of carbohydrate components estimated in these ways were calculated. Approximately 98% (by wt.) of the cellulose (C) found in original feed and digesta samples was recovered in both NDF and ADF. Recoveries of hemicellulose (X + A) in NDF from UT straw, AT straw and abomasal digesta were approximately 92, 48 and 50%, respectively. The ADF fraction of feeds and digesta contained 3–6 and 10–17% of the nitrogen and xylose, respectively, present in the original samples. Mouth to abomasum digestibilities of hemicellulose (NDF– ADF) for diets BS, BSU, BSF, BSA, BSAU and BSAF were 39, 62, 67, 29, 61 and 76%, respectively. Corresponding values for cellulose (ADF–L) were 37, 34, 50, 45, 48, and 63%, respectively. The use of NDF–ADF and ADF–L as measures of hemicellulose and cellulose contents, respectively, of feeds and digesta, and the digestibility of these carbohydrate fractions between mouth and abomasum of steers are discussed.

The Supplementation of Ammonia Treated Straws for Suckler Cows

A further experiment in a series of trials to look at the effects of treating straws on their feed values, and the responses to different supplements was carried out in the winter of 1982-83. The treatments were:-1)Untreated barley straw (DBS) plus 1.5 kg rolled barley/urea per day2)Ammonia treated barley straw (TBS) alone3)Ammonia treated wheat straw (TWS) alone4)Ammonia treated wheat straw (TWS) plus 0.5 kg rolled barley5)Ammonia treated wheat straw (TWS) plus 0.5 kg soya bean meal6)Ammonia treated wheat straw (TWS) plus 0.25 kg rolled barley and 0.25 kg fishmealThere were 7 Hereford x Friesian cows per treatment, all mature animals (third calvers or more) calved in May, bulled with a Charolais bull in July and calves weaned off and cows yarded in November 1982. The trial ran for 145 days from 25 November 1982 to 19 April I983 covering about months 4 to 8 of pregnancy. They were group fed.

Ammonia treated straw in diets for finishing beef cattle

In the absence of information on the value of treated straw as a component of the diets of finishing cattle a series of experiments was started in January 1982 to compare diets containing differing proportions of rolled mineralised barley (B) and treated spring barley straw (T) with a control ration of 75% mineralised barley (with extracted soya bean meal supplement (s)) and 25% untreated spring barley straw (U). Two treatments remained common throughout but the others were changed to widen the scope of the investigation. Fishmeal supplementation (F) was introduced as an additional factor in the third trial.

The feeding value for ruminants of straw and wholecrop barley and oats treated with anhydrous or aqueous ammonia or urea

Ammonia-treated or untreated barley straw supplemented with urea was given as the only feed to two groups of Friesian heifers weighing approximately 550 kg. The digestibility of dry matter (DM) was 58.8 and 49.9%, daily feed intake was 5.88 and 3.87 kg and daily liveweight change was +324 and -447 g for the ammonia-treated and control barley straw diets, respectively. Anhydrous or aqueous ammonia (NH 3) was injected into large round straw bales covered with plastic. The rates of degradation of barley straw in nylon bags and digestibility in vivo were the same for both ammonia treatments. The distribution of N in the bales was also similar and uniform with both treatments. No differences were recorded in the rate of degradation in nylon bags if the plastic was removed 2 or 8 weeks after treatment. Anhydrous or aqueous ammonia or isonitrogenous amounts of urea were injected into large round bags containing whole-crop barley or oats collected with a forage harvester. The digestibility of starch by steers was about 92% for ammonia-treated samples and 78% for the urea-treated samples. Urea and ammonia efficiently preserved the whole-crop materials but untreated control samples and samples treated with NaOH deteriorated during storage.

Effects of chemical treatments combined with high-pressure steaming on the chemical composition and in vitro digestibility of crop by-products

Samples of barley straw, pea straw and sugarcane bagasse were treated with sodium hydroxide, ammonium hydroxide, anhydrous ammonia, sodium chlorite, sulphur dioxide or sodium metabisulphite before, during or after high-pressure steaming at 170°C for 60 min. The steaming treatment included an additional 2-h period during which the steaming vessels cooled to room temperature. Control samples were untreated, treated with each chemical without steaming or steamed alone. The amounts of water or chemical solution added were insufficient to cause separation of a fluid fraction and chemical residues were not removed by subsequent washing. Changes in the by-products were assessed in terms of chemical composition and in vitro organic matter digestibility. Untreated barley straw had an in vitro digestibility of 38% and this was increased to 54% by high-pressure steaming alone. The highest digestibility of barley straw, 71%, was achieved by treatment with 6 g NaOH/100 g dry matter before steaming. Other treatments produced intermediate responses; treatment with anhydrous ammonia before or after steaming caused reductions in digestibility compared with the steaming treatment alone or the chemical alone and this also occurred when sulphur dioxide was applied before steaming. Untreated pea straw was 40% digestible. With the steaming treatment alone digestibility increased to 55% and with sodium hydroxide treatment alone, to 54%. No other treatment, either a chemical alone or a chemical treatment combined with high-pressure steaming, resulted in a digestibility higher than these and, in many cases, the combined treatments resulted in digestibility values similar to that of the untreated pea straw. Untreated bagasse was 27% digestible and with steaming alone it was 49% digestible. The highest digestibility of bagasse, 66%, was achieved when sodium hydroxide was provided during steaming. High-pressure steaming alone was more effective than any chemical alone, except sodium hydroxide. Combined treatments produced variable responses. The treatments caused some large reductions in the hemicellulose content of the by-products and smaller changes in contents of neutral detergent fibre and lignin.

Ammonia-treated straw in the feeding of dairy cows and growing cattle

In recent years much attention has been paid in Finland to the improvement of the feeding value of straw by ammonia. In an 11-week trial milk cows were fed untreated barely straw, ammonia-treated straw or hay ad libitum, grass silage at 30 kg per day and barely meal and protein concentrate according to milk yield. The intakes of untreated straw, treated straw and hay were 1.1, 1.4 and 3.4 kg DM per day and milk yields (4%) 16.7, 16.4 and 17.7 kg per day, respectively. In the succeeding trial of 8 weeks the same feeds were used but the amount of silage was decreased to 20 kg per day. The intake of untreated straw DM was 3.5 kg, treated straw 3.1 kg and hay 5.9 kg per day. The milk yields (4%) were 21.6, 20.9 and 21.4 kg, respectively. In a trial with growing cattle the diet included straw, barley meal and pr otein concentrate. The average daily intakes of untreated and treated barley straw from the age of 101 days to 381 days were 0.9 and 0.9 kg DM and live weight gains 1066 and 1092 g per day, respectively. In another trial from the age of 83 days to 363 days the animals consumed untreated barley straw 1.6 and treated straw 1.7 kg DM per day, and the live weight gains were 893 and 973 g per day, respectively.

Effects of treatment of barley straw with anhydrous ammonia and supplementation with heat-treated protein meals on feed intake and liveweight performance of growing lambs

Two feeding experiments were conducted in which lambs were given a basal diet of barley straw, supplemented with urea and minerals. The aim of the experiments was to increase lamb performance by (i) supplementation of the diet with protein meals that were largely undegraded in the rumen, (ii) treating the barley straw with anhydrous ammonia to increase its digestibility, or (iii) a combination of both. In Experiment 1, lambs were given the basal diet supplemented with 0, 60, 120, 180, 240, 300 or 360 g heat-treated protein-meal/kg straw. At the 300 g/kg level of supplementation, the protein pellet increased liveweight gain by 82 g/day, intake of barley straw by 110 g/day, and wool growth by 3.3 g/day, in comparison with unsupplemented lambs. In Experiment 2, untreated barley-straw or barley straw treated with anhydrous ammonia (4% w/w) was given to growing lambs. Each diet was supplemented (g/kg straw diet) with 100, 200 or 300 of two heat-treated protein-meals. Ammoniation of the barley straw increased dry matter (DM) digestibility in vitro from 49 to 57%, and hemicellulose content was reduced by 20%. Total N content of the straw was increased from 4.6 to 9.8 gN/kg DM by ammoniation, 65% of the increased N being potentially degradable in the rumen. As a result of ammoniation, digestible dry-matter intake of lambs was increased by 60 g DM/day and liveweight gain increased by 15 g/day. There was no significant difference between the two protein supplements with respect to either total feed intake or liveweight gain. Liveweight gain was significantly increased by both supplements (71, 106 and 125 g/day for each level of supplementation, respectively), but neither supplement had a significant effect on the intake of barley straw. Supplementation of a low-protein, low digestible diet of barley straw with a pelleted protein-meal considerably increased liveweight gain of growing lambs and maintained straw intake. By comparison, treatment of barley straw with anhydrous ammonia increased its digestibility, but had only a minor effect on lamb performance.

The effect of a sodium hydroxide spray treatment on digestibility of barley straw in sheep and goats

To investigate the possible potential of cheaper foodstuffs for small ruminants, an experiment was designed to compare the digestibility and acceptability of barley straw and barley straw sprayed with sodium hydroxide (NaOH). In feeding trials involving six sheep and six goats, chopped untreated barley straw (US) was compared with straw chopped and sprayed with 5 g NaOH in 60 ml solution for each 100 g straw. The treated straw (TS) was neither washed nor neutralised. Both US and TS were fed to appetite to sheep and goats, with protein, mineral and vitamin supplements and water ad libitum. Both diets were readily consumed and there were no metabolic problems. Dry Matter Intake (g kg −1 W 0.75) was significantly increased (P < 0.05) in sheep but not in goats following alkali-treatment of the straw. The Energy Digestibility and Organic Matter Digestibility (OMD) of the TS diet were significantly higher than the US diet (P < 0.05) in both species. The digestibility of Crude Fibre (CF) by sheep and goats was markedly improved (P < 0.01) following treatment and the improvement was significantly higher (P < 0.05) for the sheep fed on US than for the goats fed US. Values for the OMD and Metabolisable Energy (ME) of the US and TS were derived and both parameters were significantly increased (P < 0.05) following treatment of the straw with alkali. TS, if adequately supplemented with nitrogen, minerals and vitamins is apparently capable of supplying the ME requirements for maintenance and limited production in sheep and goats.