Ground Barley Grain Research Articles

Suppression of Fusarium wilt of spinach with hypovirulent binucleate Rhizoctonia

Four isolates of hypovirulent binucleate Rhizoctonia (HBNR) were evaluated for their ability to control Fusarium wilt of spinach (FWS) caused by Fusarium oxysporum f. sp. spinaciae (FOS). Fourteen-day-old spinach seedlings grown in paper pots with HBNR-amended soil (1% w/w ground barley grain inoculum) were transferred to artificially pathogen-infested soil. Treatments with HBNR isolates significantly (P = 0.05) reduced disease and discoloration severity by 56%–100% and 52%–100%, respectively. The numbers of colony-forming units of FOS per gram fresh weight in petioles or roots were reduced significantly (P = 0.01) in the plants treated with HBNR. HBNR isolates were well reisolated from the roots inside paper pots where they were inoculated, whereas inconsistent colonization of HBNR was recorded from the roots outside paper pots where only pathogen was inoculated. Root extracts from HBNR-treated and pathogen-challenged plants significantly inhibited germination and germling length of FOS. The fresh weight of spinach leaves in the HBNR-treated plants increased significantly (P = 0.01), as much as 53%–63%, over the untreated and pathogen-challenged plants. This is the first report of biocontrol of FWS by HBNR.

Rumen Degradation and Availability of Various Amounts of Liquid Methionine Hydroxy Analog in Lactating Dairy Cows

Ruminal escape of various amounts of methionine hydroxy analog [D,L-2-hydroxy-4-(methylthio)-butanoic acid (HMB)] was measured in an experiment designed as a 4×4 Latin square using four lactating dairy cows with cannula in the rumen and duodenum. The cows were fed a diet composed of corn silage, alfalfa haylage, rolled barley grain, canola meal, and blood meal, three times per day. The cows were fed the liquid analog each day for 1 wk before the experiment was started. On the day of the experiment, each cow received an intraruminal bolus dose of 0, 25, or 50g of the liquid analog (Alimet feed supplement, 88% HMB) or 51.2g of a dry calcium salt of the analog (86% HMB; MHA) mixed with 0.5kg of ground barley grain. A liquid phase marker (Co-EDTA) was administered as a bolus dose into the rumen at the time of administration of the methionine hydroxy analogs. Rumen and duodenal contents, and blood serum were collected at 0, 1, 3, 6, 9, 12, and 24h relative to the time of dosing. Rumen and duodenal samples were analyzed for Co and HMB, and serum was analyzed for free methionine. Fractional rate constants for the passage of the liquid marker (kp) and the decline of HMB concentration in the rumen (krHMB) were determined by nonlinear regression. Liquid passage from the rumen was similar among the four analog treatments (0.136±0.012 /h; X¯ ±SEM). Ruminal escape of HMB as a percentage of the dose (100% x kp/krHMB) did not differ between cows receiving 25, 50, and 51.2g of the methionine analogs (42.5, 41.0, and 34.9±9.0%, respectively) and averaged 39.5%. Duodenal appearance of HMB as a percentage also did not differ between cows receiving 25, 50, and 51.2g of the methionine analogs (16.2, 26.8, and 22.7%, respectively) and averaged 22%. Omasal absorption of HMB was variable ranging from 12.3 to 26.3% and averaged 17.6%. Serum methionine concentration peaked at 3 and 6h after dosing and increased in proportion to the amount of the analog administered. It was concluded that 39.5% of the methionine hydroxy analog escaped rumen degradation, the percentage of the dose that escaped the rumen was not affected by the amount or form of the methionine analog fed, and the analog that escaped ruminal degradation was likely absorbed and metabolized to methionine.

Effect of rates and extent of ruminal barley grain dry matter and starch disappearance on bloat, liver abscesses, and performance of feedlot steers

The objective was to test the hypothesis that differences in ruminal solubility and degradation of barley grain affects health and rate and efficiency of gain in feedlot steers. Ten barley grains were fed to 200 steer calves (365±27 kg) in diets containing 85.5% barley grain. Overall, 14% of the steers bloated at least once in the experiment and 16% had abscessed livers. Incidences of bloat and liver abscesses did not differ ( P>0.15) between barleys with two- versus six-row head-type morphology. The percentage of animals which bloated at least once was negatively related to the percentage of barley dry matter (DM; r=−0.60; P<0.1) and starch ( r=−0.73; P<0.05) which slowly disappeared in the rumen. Similarly, the percentage of slowly disappearing DM was correlated to the percentage of animals with liver abscesses ( r=−0.82; P<0.01). No differences in DM intake (9.7–10.9 kg per day), daily gain (1.46–1.61 kg per day), kg gain per kg feed DM consumed (0.146–0.157), or carcass characteristics were detected between steers fed the barleys. Dry matter intake, daily gain and feed efficiency of the steers were not related to starch or DM in ground barley which initially washed out of the bags or slowly disappeared in the rumen. Also, rate of disappearance of starch and DM were not related to rate or efficiency of liveweight gain. Daily gain was, however, positively related ( r=0.70; P<0.05) to the percentage of DM which slowly disappeared when rolled grain was incubated in the rumen. Similarly, the estimated degradability of rolled barley in the rumen at a ruminal passage rate of 5% per h was positively related ( r=0.66; P<0.05) to liveweight gain per feed DM consumed. In conclusion, bloat and liver abscesses increased when barley grain was rapidly solubilized and degraded in the rumen. Further, although rate and extent of ruminal disappearance of starch and DM from ground barley grain have important implications with respect to health of cattle, the effect of intrinsic differences in ruminal degradability on rate and efficiency of gain cannot be evaluated in isolation from the effects of grain processing.

Supplementing spineless cactus (Opuntia ficus-indica f. inermis) based diets with urea-treated straw or oldman saltbush (Atriplex nummularia). Effects on intake, digestion and sheep growth

Atriplex nummularia L. (atriplex) foliage and urea-treated straw have been used as nitrogen supplements for Barbarine lambs given Opuntia ficus-indica f. inermis (cactus) and their effects on feed intake, diet apparent digestibility, nitrogen balance and daily gain have been evaluated. Twenty-four lambs (mean live weight 19·9±2·79 kg) were randomly allocated to one of four experimental groups, groups 1–3 received freshly cut pads of cactus ad libitum. Group 1 was supplemented with 600 g untreated barley straw (C+US), while group 2 received 600 g urea-treated straw (C+UTS). Group 3 received 600 g untreated straw and 400 g atriplex (C+A). The amount of atriplex was calculated so that groups 2 and 3 receive iso-nitrogenous diets (i.e. C+UTS and C+A). Group 4 (US+BW) received a diet commonly offered to sheep by Tunisian smallholders, untreated straw ad libitum and 400 g of ground barley grain and wheat bran mixture (50[ratio ]50). A growth trial (60 days) followed by a digestibility trial (8 days) were performed in 1999. Irrespective of dietary treatment, cactus intake was high, averaging 500 g dry matter (DM)/day. It was not affected (P&gt;0·05) with N supplementation, as urea-treated straw or atriplex. Sheep fed cactus-containing diets drank considerably less (P&lt;0·001) water than those on the common diet (US+BW). Nitrogen provision improved significantly apparent digestibility of cactus-based diets. Urea treatment of straw increased content of digestible dry matter, organic matter, crude protein and cell wall (NDF) by 100, 100, 120 and 290 g/kg diet, respectively. There was a further increase when atriplex was provided instead of urea-treated straw. Nitrogen balance was positive across all dietary treatments but was improved when the nitrogen content of cactus-based diets was increased. Sheep fed on cactus and supplemented with atriplex retained the same amount of N as those fed the common diet (US+BW). The efficiency of microbial N production, estimated by the urinary excretion of allantoin, was improved (P&lt;0·05) with N supplementation of cactus-diets (5·7, 12·4 and 11·4 mg/kg digestible OM intake for diets C+US, C+UTS, C+A, respectively). The diet C+US covered maintenance requirements of the sheep (7·7 g of daily gain). Nitrogen supplementation of cactus-based diets raised the average daily gain of lambs. Indeed, sheep given C+UTS or C+A diets grew at a rate of 19·9 or 31·4 g/day, respectively. It is noteworthy to mention that C+A and US+BW diets had similar effect (P&gt;0·05) on sheep growth (31·4 and 39·7 g/day, respectively). It is concluded that cactus may be considered as an emergency feed and water source for sheep in arid and semi-arid zones. Nitrogen supplementation of cactus-based diets with urea-treated straw or atriplex foliage improved the feeding value of these diets and consequently sheep growth. A cactus-based diet, supplemented with atriplex, promoted similar growth in sheep as the commonly used diet (US+BW).

In vitro effects of steroidal saponins fromYucca schidigera extract on rumen microbial protein synthesis and ruminal fermentation

In a first experiment, ground alfalfa hay and rolled barley grain were incubated in buffered ruminal fluid with and without Yucca schidigera extract (YE, 0 or 10 mg ml−1). Gas and total VFA production from barley grain were increased (P < 0.05) by YE during the first 10 h of incubation; from alfalfa hay, these were reduced (P < 0.001) throughout the 24 h. Yucca extract reduced (P < 0.001) acetate/propionate ratios and ammonia concentrations, irrespective of substrate. In a second experiment, ground barley grain was incubated in a buffered suspension of mixed ruminal microbes obtained by low-speed centrifugation of ruminal fluid. Steroidal saponins (SAP) isolated from YE were included at 0, 15, 75 or 225 µg ml−1. Microbial incorporation of 15N was increased (P < 0.05) by 15 µg SAP ml−1 but decreased (P < 0.05) by 225 µg SAP ml−1. Gas and VFA production peaked with 75 µg SAP ml−1 and were elevated (P < 0.05) relative to control in the presence of 75 µg SAP ml−1. Microbial protein synthesis was increased (P < 0.05) by SAP at 15 µg ml−1 and reduced (P < 0.05) by the higher concentrations. Acetate/propionate ratios were linearly reduced by SAP from 8 to 24 h incubation (P < 0.01). The effects of SAP on digestive microbes were less pronounced (P < 0.05) with barley grain digestion than with alfalfa. A YE × diet interaction was recorded. The biological activity of YE was shown to be attributable to its SAP and to be diet-dependent. © 2000 Society of Chemical Industry. Contributions of Y Wang, T A McAllister, L J Yanke and Z Xu © Minister of Public Works and Government Services Canada 2000

Quantitation of bioresmethrin, a synthetic pyrethroid grain protectant, by enzyme immunoassay

An enzyme immunoassay was developed for the synthetic pyrethroid, bioresmethrin, by use of a novel approach for synthesis of the pyrethroid-protein hapten conjugate for antibody preparation. Bioresmethrin was hydrolyzed at the ester linkage, and following protection of the chrysanthemic acid group, the 2-methylprop-1-ene substituent was oxidatively cleaved. The newly formed and unprotected acid group was reesterified to the other bioresmethrin hydrolysis product [[2-(phenylmethyl)-4-furyl]-methanol], and following substitution of the protecting group, the hapten was coupled to either protein for antibody production or peroxidase for use in the immunoassay. The most sensitive assay employed an antibody prepared to a derivative with a 4-carbon spacer arm between bioresmethrin and carrier protein, but used a bioresmethrin-enzyme reporter prepared using a 4-(aminomethyl)cyclohexane-carboxylic acid spacer arm (limit of detection 2 ppb in buffer, 50 ppb in whole wheat or barley grain). Good correlations between HPLC and ELISA determinations of bioresmethrin in whole or ground barley grain were obtained. The sensitivity of the assay was slightly lower in ground grain or flour milling fractions due to interference from coextractives in methanol extracts. Apart from resmethrin, of which bioresmethrin is the 1R,3R-trans-isomer, the assay did not detect a variety of other pyrethroids in commercial use.

Retention of nitrogen from ground barley grain supplemented with lucerne or barley leaf juice in long-term balance experiments conducted with rats.

AbstractThe biological value (BV) and true digestibility of lucerne and barley juice protein mixed with ground barley grain were estimated using the Thomas‐Mitchell balance method with rats. The BV with forage barley juice protein was similar to that of barley grain protein alone and was not improved by any of the applied treatments. The BV with lucerne juice protein was lower and was improved by separating the ‘brown juice’ after heat coagulation. Better results were obtained in a group fed diets with lowered levels of potassium and calcium which suggested an imbalance in the mineral content of lucerne juice; there was no difference in water consumption. The haemoglobin content of the blood of rats fed lucerne or barley juice alone was lower than that of animals fed plant juice/barley grain mixtures. No pathological lesions were observed in the guts, kidneys and livers of the rats.