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PubMed2004

Influence of method of whole wheat inclusion and xylanase supplementation on the performance, apparent metabolisable energy, digestive tract measurements and gut morphology of broilers.

1. The aim of the present study was to examine the influence of whole wheat inclusion and xylanase supplementation on the performance, apparent metabolisable energy (AME), digesta viscosity, and digestive tract measurements of broilers fed on wheat-based diets. The influence of the method of whole wheat inclusion (pre- or post-pelleting) was also compared. A 3 x 2 factorial arrangement of treatments was used with three diet forms (648 g/kg ground wheat [GW], GW replaced by 200 g/kg of whole wheat before [WW1] or after cold-pelleting [WW2]) and two xylanase levels (0 and 1000 XU/kg diet). 2. Birds given diets containing whole wheat had improved weight gains, feed efficiency and AME compared to those fed on diets containing ground wheat. The relative gizzard weight of birds fed WW2 diets was higher than in those fed GW and WW1 diets. Pre-pelleting inclusion of whole wheat had no effect on relative gizzard weight. Post-pelleting inclusion of whole wheat resulted in greater improvements in feed efficiency and AME than the pre-pelleting treatment. 3. Xylanase supplementation significantly improved weight gain, feed efficiency and AME, irrespective of the wheat form used. Viscosity of the digesta in the duodenum, jejunum and ileum were reduced by xylanase addition. Xylanase supplementation reduced the relative weight of the pancreas. 4. Neither xylanase supplementation nor whole wheat inclusion influenced the relative weight and length of the small intestine. 5. Xylanase supplementation increased ileal villus height. A significant interaction between diet form and xylanase was observed for ileal crypt depth. Xylanase supplementation had no effect on crypt depth in birds fed on diets containing GW, but increased the crypt depth in WW2 diets. No significant effects of diet form and xylanase supplementation were observed for the thickness of the tunica muscularis layer of gizzard or villus height, crypt depth, goblet cell numbers or epithelial thickness in the ileum. 6. Improved performance observed with post-pelleting inclusion of whole wheat was associated with increased size of the gizzard and improved AME. The gizzard development hypothesis, however, will not explain the improvements observed with pre-pelleting inclusion of whole wheat, suggesting the involvement of other factors.

Animal Nutritional Physiological Phenomena↗
PubMed1995

Sequential feeding of whole wheat to growing broiler chickens.

1. Four broiler feeding trials were performed to examine the suitability of a whole wheat sequential feeding regimen for commercial broiler production. The sequential feeding programme gave a continuous cycle of ad libitum access to only whole wheat followed by the same time of access to only a pelleted diet. The pelleted diet provided a concentration of nutrients to balance that provided by the whole wheat. This was called a balancer diet. 2. The first trial used 144 cage-reared broilers from 28 to 49 d of age. Four different times of access (4, 8, 12 and 24 h) to the two alternate foods were compared. A whole wheat choice-feeding treatment and a complete single diet treatment were also compared. Whole wheat accounted for over 40% of the broilers' total food intakes when they were given the sequential feeding treatments of 8 h or greater. The whole wheat intakes of the birds given the 4 h sequential feeding and the choice-feeding were only 20 and 5% respectively. There was a non linear relationship between the weight gains of the broilers and the length of the sequential feeding period (P < 0.01). The growth rates of the broilers given sequential feeding were lowest (P < 0.05) in the 4-h feeding periods but highest (P < 0.05) in the 8-h periods. Weight gains decreased (P < 0.01) linearly as the sequential feeding periods were increased above 8 h. 3. A second trial, using 144 cage-reared broilers, examined the effect of different balancer compositions or different wheat varieties in 8-h sequential feeding. The broilers selected more whole wheat in their diet when they were given balancers with increased cereal contents. However, these broilers did not eat enough whole wheat to compensate for the reduced cereal content of the balancers and their overall diets had lower energy:protein ratios. The two different wheat samples did not result in any differences (P > 0.05) in the proportion of whole wheat selected by the broilers. 4. A third trial compared the diet selections, weight gains, food intakes and water excretions of 72 cage-reared broilers given whole wheat feeding regimens. The growth rates of the broilers given a loose mix of whole wheat and a pelleted balancer diet were similar (P > 0.05) to broilers given a complete single diet. The growth rates of these two groups were 7% greater (P < 0.05) than broilers given choice-feeding or 8-h sequential feeding.(ABSTRACT TRUNCATED AT 400 WORDS)

Animal Feed↗
PubMed1996

A comparison of the energy availability for chickens of ground and whole grain samples of two wheat varieties.

1. The objective of this study was to examine whether the energy availabilities of two wheat samples, which differed in endosperm hardness, were changed when they were fed ground or as whole grains to chickens. Wheat samples of a variety Haven (hard endosperm) and a variety Riband (soft endosperm), both harvested in 1993 from the same growing site, were used in the experiment. 2. True metabolisable energy (TMEn) was measured in a flock of 24 adult cockerels and the mean of all the samples was 14.68 MJ/kg dry matter (DM). The TMEn of ground wheat was 0.306 MJ/kg DM greater (P < 0.05) than whole grain. There was no significant difference (P > 0.05) in TMEn between the Riband and Haven wheat samples and there were no (P > 0.05) variety x wheat form interactions. 3. The apparent metabolisable energy (AMEn) of the wheat samples was determined with 96 broiler chickens from 19 to 27 d of age. Different amounts of either whole or ground wheat samples were added to a basal diet. Extrapolation of the regression lines indicated AMEn concentrations (MJ/kg DM) of ground Haven 14.33, whole Haven 14.28 ground Riband 14.33 and whole Riband 14.51. There was no evidence (P > 0.05) that whole grain wheat had a different AMEn than ground wheat. 4. A feeding trial used 192 broiler chickens in 48 cages from 24 to 42 d of age. They were fed on a broiler grower diet either mixed with ground wheat before pelleting or with the pelleted grower diet loosely mixed with the whole wheat. There were no differences (P > 0.05) between the 2 wheat varieties or the diet form in growth rates or food conversion ratios. The growth rates of the broilers given a conventional grower and finisher dietary regimen tended (P > 0.05) to be slightly greater than the broilers given the wheat-diluted diets.

Animal Feed↗
PubMed1998

White and wholemeal flours from wheats of low and higher apparent metabolizable energy differ in their nutritional effects in rats.

Wheats used for feeding poultry differ considerably in the ratio of soluble to insoluble non-starch polysaccharides (NSP) and apparent metabolizable energy (AME). We have examined effects of whole and white flour from a wheat of low (12.02 MJ/kg of dry matter) and high (14.52 MJ/kg of dry matter) AME in rats fed a cholesterol-free diet. NSP concentrations were higher in whole flour from the low AME wheat but similar in both white flours. In contrast to chickens, food intake and body weight gain of rats were unaffected by diet. Plasma cholesterol concentrations were lower in rats fed whole wheat and low AME wheat. Cecal bile acids and neutral sterol pools were larger in rats fed whole wheat but were unaffected by wheat type. Negative correlations were found between digesta steroid pools and plasma cholesterol, consistent with greater fecal steroid excretion. Cecal digesta was greater in rats fed whole wheat and low AME wheat. Digesta pH was lower in rats fed whole wheat, but there was a significant interaction between wheat and flour type with lower pH in rats fed low AME white flour. Total volatile fatty acids (VFA) and acetate and butyrate pools were larger in rats fed whole wheat than in those fed white flour. Total and individual VFA pools were larger in rats fed low AME flours than in those fed high AME flours, apparently due to greater cecal starch fermentation in the former. Factors affecting wheat AME in chickens affect important metabolic variables in rats and may have similar actions in other species including humans.

Animal Nutritional Physiological Phenomena↗
PubMed2004

Influence of whole wheat and xylanase on broiler performance and microbial composition and activity in the digestive tract.

An experiment was carried out to study the effect of different forms of wheat (airtight silo stored whole wheat, conventionally stored whole wheat, and ground wheat included in pellets) and dietary xylanase addition on production results and gastrointestinal characteristics of broiler chickens. Ileal viscosity, pancreatic digestive enzyme activities, and the composition and activity of the intestinal microflora were considered as response parameters. Differences between the 2 types of whole wheat with respect to the various measured parameters were marginal, whereas distinct differences were found between pellet-fed birds and birds receiving whole wheat. Whole wheat feeding improved feed conversion ratio and reduced water consumption (P < 0.001). Compared with pellets, whole wheat increased the relative weight of pancreas and gizzard and the dry matter concentration of gizzard content (P < 0.001). Whole wheat feeding reduced the pH in the gizzard contents (P < 0.01) and increased ileal viscosity. The addition of xylanase reduced ileal viscosity in birds receiving whole wheat to the same level as in pellet-fed birds. Whole wheat feeding resulted in lower activities of amylase in pancreatic tissue (P = 0.054), whereas xylanase addition increased chymotrypsin (P = 0.030) and lipase activities (P = 0.052). Whole wheat feeding resulted in lower intestinal numbers of lactose-negative enterobacteria (P < 0.05) and tended to reduce the ileal and cecal numbers of Clostridium perfringens (P < or = 0.08). It is concluded that whole wheat feeding stimulates gizzard function, which in turn prevents potentially pathogenic bacteria from entering the intestinal tract.

Amylases↗
PubMed1999

Amino acid digestibilities in different samples of wheat shorts for growing pigs.

An experiment was carried out to investigate the variability in apparent ileal amino acid (AA) digestibilities in simulated samples of wheat shorts consisting of different proportions of wheat bran (WB), wheat shorts (WS), and wheat flour (WF), hereafter referred to as wheat fractions. The proportions of WS, WB, and WF and the NDF content (DM basis) of the wheat fractions were as follows: A, 70% WS, 30% WB, and 42.3% NDF; B, 85% WS, 15% WB, and 41.8% NDF; C, 100% WS and 41.3% NDF; D, 85% WS, 15% WF, and 35.2% NDF; and E, 70% WS, 30% WF, and 29.5% NDF. Six barrows, average initial BW of 37.2 kg, fitted with a simple T-cannula at the distal ileum, were fed one of six experimental diets according to a 6 x 6 Latin square design. Six diets were formulated to contain 17% CP (as-fed basis). Diets A, B, C, D, and E contained 17.53% soybean meal (SBM), which contributed 50% of the CP in these diets. The wheat fractions contributed the remaining 50% of the CP in these diets. Diet F contained 35.05% SBM, which was the sole source of dietary CP. Chromic oxide was used as the digestibility marker. During the first experimental period, the daily dietary allowance was provided at a rate of 5% (wt/wt) of the average BW. Thereafter, the daily dietary allowance was increased by 100 g at each successive period. Each experimental period comprised 12 d. Following a 7-d adaptation period, feces were collected for 48 h and ileal digesta for a total of 24 h. The apparent ileal digestibilities of AA in the wheat fractions were calculated using the difference method. The digestibilities were usually lowest in the wheat fractions containing WB and highest in those containing no WB. The average of the digestibilities of the indispensable AA was 63.5% for wheat fraction A, which contained 30% WB, and 71.9% for wheat fraction C, which did not contain WB. There were no differences (P > .05) in lysine digestibilities among the wheat fractions, which ranged from 54.7 to 64.1%. Of the indispensable AA, with the exception of arginine, lysine, and methionine, the apparent ileal digestibility values of AA were negatively correlated (P < .05) with the NDF content in the wheat fractions.

Amino Acids↗
PubMed2004

[Inter-laboratory evaluation studies for development of notified ELISA methods for allergic substances (wheat)].

Extracts of sausage, sauce, pasta sauce, fish paste and cereal spiked with wheat standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of both ELISA methods using a Wheat Protein ELISA Kit (Gliadin kit) and a FASTKIT Wheat ELISA Kit (Wheat ELISA kit) were mostly below 10%. Mean recoveries of the wheat standard protein from the food extracts were over 40% in the two ELISA methods except those from cereal extract determined using the Wheat ELISA kit. Repeatability relative standard deviations of wheat standard protein in the five food extracts were in the ranges of 16-26.9% and 3.7-36.2% for the Gliadin kit and the Wheat ELISA kit, respectively. Reproducibility relative standard deviations of wheat standard protein in the five food extracts were 21.6-38.5%, 29.7-53.8% for the Gliadin kit and the Wheat ELISA kit, respectively. The recoveries of wheat standard protein from the cereal extract were improved by the increasing the amount of antibody coated on the plate in the Wheat ELISA kit. The detection limits of both ELISA methods were 1 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of wheat protein levels in extracts of sausage, sauce, pasta sauce, fish paste and cereal.

Allergens↗
PubMed2006

[Enhancement of nonsteroidal, anti-inflammatory drugs and preventive effect of antihistamines and disodium cromoglycate on wheat allergy].

BACKGROUND: Aspirin has been known to be an enhancer to wheat allergy, including wheat-dependent, exercise-induced anaphylaxis. OBJECTIVE: To investigate whether nonsteroidal, anti-inflammatory drugs (NSAIDs) other than aspirin would enhance allergic reactions after wheat ingestion and whether antihistamines and disodium cromoglycate would prevent these reactions. METHODS: Seven cases, whose reactions after wheat ingestion were enhanced by aspirin on challenge tests, were enrolled. Skin prick tests (SPT) and CAP-RAST were undergone for wheat and gluten. We used challenge tests of wheat after pretreatment of NSAIDs and preventive drugs. RESULTS: Four cases were diagnosed with wheat allergy, 3 cases had wheat-dependent, salicylic acid-induced anaphylaxis. SPT and CAP-RAST were positive for wheat and gluten in 5 of 7 cases and 4 of 7 cases, respectively. Dicrofenac enhanced the allergic reactions after wheat ingestion in 1 of 2 cases, whereas etodolac failed to enhance the symptoms in all 5 cases performed. Furthermore, disodium cromoglycate could not completely prevent the allergic reaction in all 4 cases and even enhanced the reaction in 1 case of them. To see an inhibitory effect of antihistamines on the symptoms, fexofenadine (in 2, 1 and 1 case, respectively), olopatadine, and chlorpheniramine were administrated before the challenge test, and as a result these drugs were found to have inhibitory effects on the allergic reaction. CONCLUSION: In this study, it was suggested that etodolac might be a relatively safe anti-inflammatory drug on wheat allergy and antihistamines could prevent allergic reactions more than DSCG in patients with wheat allergy.

Adult↗
PubMed2005

Development and characterization of wheat- Leymus racemosus translocation lines with resistance to Fusarium Head Blight.

Wheat scab (Fusarium Head Blight, FHB) is a destructive disease in the warm and humid wheat-growing areas of the world. Finding diverse sources of FHB resistance is critical for genetic diversity of resistance for wheat breeding programs. Leymus racemosus is a wild perennial relative of wheat and is highly resistant to FHB. Three wheat- L. racemosus disomic addition (DA) lines DA 5 Lr#1, DA 7 Lr#1 and DALr.7 resistant to FHB were used to develop wheat- L.racemosus translocation lines through irradiation and gametocidal gene-induced chromosome breakage. A total of nine wheat-alien translocation lines with wheat scab resistance were identified by chromosome C-banding, GISH, telosomic pairing and RFLP analyses. In line NAU 614, the long arm of 5 Lr#1 was translocated to wheat chromosome 6B. Four lines, NAU 601, NAU 615, NAU 617, and NAU 635, had a part of the short arm of 7 Lr#1 transferred to different wheat chromosomes. Four other lines, NAU 611, NAU 634, NAU 633, and NAU 618, contained translocations involving Leymus chromosome Lr.7 and different wheat chromosomes. The resistance level of the translocation lines with a single alien chromosome segment was higher than the susceptible wheat parent Chinese Spring but lower than the alien resistant parent L. racemosus. At least three resistance genes in L. racemosus were identified. One was located on chromosome Lr.7, and two could be assigned to the long arm of 5 Lr#1 and the short arm of 7 Lr#1.

Chromosome Banding↗
PubMed2000

Inhibitory effect of wheat fibre extract on calcium absorption in Caco-2 cells: evidence for a role of associated phytate rather than fibre per se.

BACKGROUND: In spite of the strong evidence for the beneficial health effects of dietary fibres, one of the potential nutritional disadvantages of high fibre diets is the adverse effect on the bioavailability of micronutrients, especially minerals and trace elements. With regard to Ca, there is considerable evidence that phytate, which is associated with fibre in many foods, such as cereals and soya products, inhibits Ca absorption. However, there is some doubt as to whether fibres per se have an influence on Ca absorption. AIM OF THE STUDY: Therefore, the purpose of this study was to investigate the effect on Ca absorption of two cereal-based fibre extracts (wheat bran and barley hull). In addition, in order to distinguish between the effect of the fibre components per se and the associated phytate content in these fibre extracts, we investigated the effect of dephytinised wheat and barley fibre extracts and the effect of phytate, as sodium phytate at levels present in the fibre extracts, on Ca absorption. Ca absorption was assessed in Caco-2 cells, as a model for studying Ca absorption in humans. METHODS: The effect of wheat and barley fibre extracts, dephytinised wheat and barley fibre extracts, cellulose, and of sodium phytate on transepithelial 45Ca transport and 45Ca uptake was studied in differentiated Caco-2 cells grown on permeable filter supports. Wheat and barley fibre extracts were dephytinised with wheat phytase. RESULTS: Wheat fibre extract had a 3.2-fold higher phytate content (48.0 mmol/kg) than barley fibre extract (15.1 mmol/kg). Enzymatic dephytinisation of both fibre extracts reduced the phytate content to undetectable levels. The rate of transepithelial 45Ca transport across Caco-2 cell monolayers and the uptake of 45Ca into Caco-2 cells were unaffected by cellulose or barley fibre extract. On the other hand, inclusion of wheat fibre extract in the Ca transport buffer (50 g fibre/l) significantly reduced the rate of 45Ca transport (by 17 and 19% respectively) and the uptake of 45Ca (by 24 and 25% respectively) relative to a fibre-free buffer and a control fibre (cellulose) transport buffer. Increasing the phytate concentration of the transport buffer from 0 to 2 mM (a level close to that in the wheat fibre containing buffer) significantly reduced the rate of 45Ca transport (by 16%) and 45Ca uptake (by 26%). Dephytinisation of the wheat fibre extract removed its inhibitory effects on 45Ca transport and e.g. 45Ca uptake. CONCLUSION: The results from the present study in Caco-2 cells suggest that it is the phytate in wheat fibre extract which is the major inhibitory factor of Ca absorption and that wheat fibre per se has little if any inhibitory effect on Ca absorption. In addition, the results of this study support the usefulness of Caco-2 cells for investigating the effects of dietary factors on the cellular uptake and transepithelial intestinal transport of Ca.

Absorption↗
PubMed1975

Inhibition of amylases from different origins by albumins from the wheat kernel.

The amylase activity of water extracts from 18 insect species, from 23 marine species and from 17 different species of birds and mammals was determined quantitatively. The inhibition of amylase in these extracts by three albumin fractions from the mature wheat kernel, which had been separated according to their molecular weights (60 000, 24 000 and 12 500 D), was determined as well. The inhibition activity of the three albumin fractions toward amylases extracted from a number of cereal species or from immature and germinating wheat kernel was also tested. The extracts from insects that are destructive of wheat grain and stored wheat products showed much higher amylase activities as compared to the other insect species that do not attack wheat and wheat products. On the basis of the effectiveness with which the three albumin fractions inhibit their activities, the amylase preparations tested were divided into susceptible, partially susceptible and resistent. Susceptible amylases, inhibited by any of the three albumin fractions, were found mainly in insects that attack wheat and in marine species. Partially susceptible amylases, inhibited by only one or two of the three albumin fractions, were present in a few avain and mammalian species including man. Resistent amylases were largely distributed in cereal, avian and mammalian species as well as in insect species that do not usually attack wheat grain or wheat flour products. At no stage of development, wheat alpha-amylase was inhibited by the albumin fractions from the mature kernel. The 12 500 dalton albumin fraction was the most effective in inhibiting insect amylases, but it was inactive toward avian and mammalian amylases. The 24 000 dalton albumin fraction was the most effective in inhibiting amylases from marine avian and mammalian species and inhibited as much as 33 amylases over 66 different amylases tested. It is suggested that protein inhibitors of amylase contributed to natural selection of polyploid wheats by giving some insect resistence to such wheats, even though some insect species were able to overcome this biochemical defense toa large degree by producing higher amylase activities.

Albumins↗
PubMed1992

Mechanism of antimutagenicity of wheat sprout extracts.

In this paper we have demonstrated that wheat sprout extract, which has been shown to be antimutagenic towards benzo[a]pyrene (BP), reduced formation of BP metabolites by hepatic microsomes of either benzo[a]pyrene- or phenobarbital-treated rats as analyzed in high-pressure liquid chromatography (HPLC). Comparing the time dependence of profiles and values of BP metabolites, formed in experiments in which the same dose of wheat sprout extract was added to the incubation medium, it has been observed that the later this extract was added the higher the percent of BP that was metabolized. In a bacterial test (cytochrome P450 induction assay) high inhibition of mutagenic activity of cyclophosphamide and ethidium bromide, in the presence of wheat sprout extract, reflected decreased levels of cytochromes P4502B1 and P4501A1 respectively. Decreased levels of both cytochromes P4501A1 and P4502B1 were also observed in either wheat sprout extract- or wheat sprout extract plus benzo[a]pyrene-treated rats. In all of these studies it has been observed that wheat sprout extract displays much more affinity for cytochrome P4501A1 than for the P4502B1 form. On the other hand the wheat sprout extract had higher affinity for carcinogen binding protein (4S protein) than for the aryl hydrocarbon receptor. The strong inhibition of BP mutagenicity and BP metabolism with non-chlorophyllic wheat sprout extract suggests that chlorophyll is not the main compound responsible for the antimutagenic activity of wheat sprout extract. The similar chromatographic behavior of both the main inhibitory fraction, obtained from wheat sprout extract, and two pure glycosides of apigenin--shaftoside, purified from wheat sprout extract and synthetic swertisine--suggests that antimutagenic compound(s) contained in the wheat sprout extract belong(s) to this family of flavonoids.

Animals↗
PubMed2005

Changes of anti-oxidative enzymes and membrane peroxidation for soil water deficits among 10 wheat genotypes at seedling stage.

Drought is one of the major factors limiting crop production globally, with increasing global climate change making the situation more serious. Wheat is the staple food for more than 35% of world population, so wheat anti-drought physiology study is of importance to wheat production and biological breeding for the sake of coping with abiotic and biotic conditions. Much research is involved in this hot topic, but the pace of progress is not so large because of drought resistance being a multiple-gene-control quantitative character and wheat genome being larger (16,000 Mb). On the other hand, stress adaptive mechanisms are quite different, with stress degree, time course, materials, and experimental plots, thus increasing the complexity of the issue in question. Additionally, a little study is related to the whole life circle of wheat, which cannot provide a comprehensive understanding of its anti-drought machinery. We selected 10 kinds of wheat genotypes as materials, which have potential to be applied in practice, and measured relative change of anti-oxidative enzymes and membrane peroxidation through wheat whole growth-developmental circle (i.e. seedling, tillering and maturing). Here, we firstly reported the results of seedling stage as follows: (1) 10 wheat genotypes can be grouped into three kinds (A-C, respectively) according to their changing trend of the measured indices; (2) A performed better resistance drought under the condition of treatment level 1 (appropriate level), whose activities of anti-oxidative enzymes (POD, SOD, CAT) were higher and MDA lower and chlorophyll a+b higher; (3) B exhibited stronger anti-drought under treatment level 2 (light stress level), whose activities of anti-oxidative enzymes were higher, MDA lower and chlorophyll higher; (4) C expressed anti-drought to some extent under treatment level 3 (serious stress), whose activities of anti-oxidative enzymes were stronger, MDA lower and chlorophyll higher; (5) these results demonstrated that different wheat genotypes have different physiological mechanisms to adapt themselves to changing drought stress, whose molecular basis is discrete gene expression profiling (transcriptom); (6) our results also showed that the concept accepted by most researchers, 70-75% QF is a proper supply for plants, was doubted, because this level could not reflect the true suitable level of wheat. The study in this respect is the key to wheat anti-drought and biological saving-water; (7) our research can provide insights into physiological mechanisms of crop anti-drought and direct practical materials for wheat anti-drought breeding.

Antioxidants↗
PubMed2000

Antimutagenic effects of wheat bran diet through modification of xenobiotic metabolising enzymes.

Diets containing wheat bran (WB) protect against cancers of the colon or breast in rats, and may be beneficial in humans. In a previous study of rats treated with the carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), inclusion of 10% wheat bran in the diet led to an apparent reduction in IQ metabolites but not of intact IQ in plasma. In the present study, male Wistar rats were fed diets containing 0, 10 or 20% wheat bran, and effects on xenobiotic metabolising enzymes compared. Wheat bran-supplementation showed differential effects on phase I enzymes, significantly increasing the activity of hepatic cytochrome P450 isozyme CYP3A2, but slightly reducing the activity of CYP1A1/2. The activities of both hepatic phase II detoxification enzymes glutathione-S-transferase and glucuronosyl transferase were also reduced. Western blotting revealed similar effects on expression of the proteins. Interestingly, the expression of xenobiotic metabolising enzymes (XME) in the colon appeared to be modulated independently of hepatic XME. Although the wheat bran-supplemented diet still led to an increased expression of CYP3A, it now slightly increased CYP1A in the colon. However, 20% wheat bran significantly increased the expression of both glutathione transferase isozymes, GST A1 & A2, in the colon. Natures Gold (NG) is a commercial wheat bran derivative which is lower than wheat bran in dietary fibre, but enriched in vitamins, minerals and various phytochemicals. Dietary supplementation with 20% Natures Gold led to similar trends as seen in wheat bran-fed rats, but more potent effects in both hepatic and colonic enzymes. The significance of these changes for activation of carcinogens to mutagenic metabolites was investigated using the Salmonella/mammalian microsome mutagenicity test. The activation of IQ and benzo[a]pyrene, but not cyclophosphamide, to a mutagen by hepatic S9 from wheat bran-fed or Natures Gold-fed rats was significantly reduced compared with S9 from animals on a diet lacking wheat bran. We suggest that modulation of xenobiotic metabolising enzymes may be an important component of cancer protection by wheat bran, and this effect may relate to micronutrients or cancer-protective non-nutrient phytochemicals rather more than to dietary fibre.

Animals↗
PubMed2002

Effects of Fusarium toxin contaminated wheat and of a detoxifying agent on performance of growing bulls, on nutrient digestibility in wethers and on the carry over of zearalenone.

Experiments were carried out to examine the effects of a Fusarium contaminated wheat (10 mg deoxynivalenol and 0.76 mg zearalenone, ZON, per kg dry matter) and of a detoxifying agent (Mycofix Plus, Biomin GmbH, Herzogenburg, Austria) on the growing performance of bulls, carry-over of ZON and its metabolites into body fluids and tissues, and on nutrient digestibility in wethers. The experiments were designed according to a complete two by two factorial approach which meant that both the uncontaminated control wheat and the Fusarium toxin contaminated wheat were tested both in the absence and presence of Mycofix Plus. The growing experiment with bulls (n = 14 per treatment) covered the live weight range between 244 kg and 460 kg. The respective wheat batches were included in the concentrate portion at 65%. Concentrates were fed according to plan whereas maize silage was offered for ad libitum consumption. Daily dry matter intake and live weight gain [kg per animal and day] were 7.40, 7.52, 7.51 and 7.49 and 1.367, 1.296, 1.380 and 1.307 for bulls fed the unsupplemented control wheat, the supplemented control wheat, the unsupplemented and Fusarium toxin contaminated wheat and the supplemented Fusarium toxin contaminated wheat, respectively. ZON and its metabolites were not detected in edible tissues. The most striking effects of feeding the Fusarium toxin contaminated wheat on carcass characteristics were a reduced dressing percentage, an increased weight of the emptied gastro-intestinal tract and a reduced weight of the testicles. No effect of the detoxifying agent was seen for these parameters whereas heart weight increased independently of Fusarium toxin contamination of the concentrates. Nutrient digestibility of the two wheat batches, unsupplemented or supplemented with Mycofix Plus was evaluated according to the difference method using wethers. Presence of Fusarium toxins in wheat did not influence its feeding value. The effects of the addition of the detoxifying agent were mycotoxin unspecific and resulted in an increase in apparent digestibility of crude protein and a decrease in crude fiber digestibility. It is concluded that feeding of Fusarium toxin contaminated wheat did not adversely affect performance of growing bulls (approximately 2.2 mg DON and 0.1 mg ZON per kg complete ration at a reference dry matter content of 88%) or nutrient digestibility in wethers. The effects of the detoxifying agent Mycofix Plus on growing performance and on nutrient digestibility were rather Fusarium toxin unspecific. The slightly negative effects on growing performance needs to be examined further.

Animal Feed↗
PubMed2005

Wheat curl mite (Acari: Eriophyidae) dispersal and its relationship with kernel red streaking in maize.

Wheat curl mites, Aceria tosichella Keifer, dispersing from wheat (Triticum spp.) to nearby corn (Zea mays L.) fields play a role in the development of kernel red streaking in corn. These studies were undertaken to verify the relationship of wheat curl mite to kernel red streaking, to determine whether wheat is the main source of curl mites dispersing into corn and to determine whether planting corn in temporal or spatial isolation of wheat is a valid management strategy. These studies were conducted on farm fields using sticky traps to monitor mites, followed by sampling mature grain for kernel streaking in southwestern Ontario from 1999 to 2002. The dominant source mites were winter wheat. Mite dispersal occurred during the first 3 wk of winter wheat maturation after the wheat had reached Zadoks stage 87. Mite dispersal corresponded to prevailing winds in the area with the lowest number of mites and the lowest severity of kernel red streaking occurring 60 m from wheat fields planted to the north, south, and east of cornfields and 90 m from wheat fields planted to the west of cornfields. The severity of kernel red streaking was positively correlated with the density of wheat curl mites in corn; however, the correlation was weak and kernel red streaking was still high in many cornfields when few or no mites were present. These findings suggest that wheat curl mite migration into corn is not entirely predictive of the incidence and severity of kernel red streaking.

Acari↗
PubMed2000

Uptake and retranslocation of leaf-applied cadmium (109Cd) in diploid, tetraploid and hexaploid wheats.

Uptake and retranslocation of leaf-applied radiolabeled cadmium (109Cd) was studied in three diploid (Triticum monococcum, AA), four tetraploid (Triticum turgidum, BBAA) and two hexaploid (Triticum aestivum, BBAADD) wheat genotypes grown for 9 d under controlled environmental conditions in nutrient solution. Among the tetraploid wheats, two genotypes were primitive (ssp. dicoccum) and two genotypes modern wheats (ssp. durum). Radiolabelled Cd was applied by immersing the tips (3 cm) of mature leaf into a 109Cd radiolabelled solution. There was a substantial variation in the uptake and export of 109Cd among and within wheat species. On average, diploid wheats (AA) absorbed and translocated more 109Cd than other wheats. The largest variation in 109Cd uptake was found within tetraploid wheats (BBAA). Primitive tetraploid wheats (ssp. dicoccum) had a greater uptake capacity for 109Cd than modern tetraploid wheats (ssp. durum). In all wheats studied, the amount of the 109Cd exported from the treated leaf into the roots and the remainder of the shoots was poorly related to the total absorption. For example, bread wheat cultivars were more or less similar in total absorption, but differed greatly in the amount of 109Cd retranslocated. The diploid wheat genotype 'FAL-43' absorbed the lowest amount of 109Cd, but retranslocated the greatest amount of 109Cd in roots and remainder of shoots. The results indicate the existence of substantial genotypic variation in the uptake and retranslocation of leaf-applied 109Cd. This variation is discussed in terms of potential genotypic differences in binding of Cd to cell walls and the composition of phloem sap ligands possibly affecting Cd transport into sink organs.

Biological Transport↗
PubMed1990

Chloramphenicol Stimulates the Accumulation of Light-Harvesting Chlorophyll a/b Protein II by Affecting Posttranscriptional Events in the Chlorina CD3 Mutant Wheat.

The levels of total chlorophyll (Chl), total carotenoids, light-harvesting Chl a/b apoprotein of photosystem II (LHCPII), and light-harvesting Chl a/b apoprotein (LHCP) mRNA were examined in the CD3 chlorina mutant wheat (Triticum aestivum, L.) after 18 hours greening at either a low (3 micromoles of photons per square meter per second) or moderate (200 micromoles of photons per square meter per second) irradiance. The Chl b and LHCPII deficient mutant wheat accumulated significantly greater levels of Chl and LHCPII when greened under low irradiance than when greened under a moderate irradiance level. The level of LHCP mRNA, as measured by dot-blot and Northern hybridization analyses to a cDNA probe, increased in response to the irradiance level in the wheat. Applications of chloramphenicol (CAP) to the mutant wheat increased total Chl, Chl b, and LHCPII accumulations at both irradiance levels. Even though the CAP-treated CD3 mutant wheat accumulated similar levels of plastid pigments as those of CAP-treated wild type, the LHCPII amounts were much higher in the wild type than in the CD3 mutant of wheat. CAP treatment did not significantly increase the LHCP mRNA level in either wheat. Applications of either benzyladenine or CAP to the mutant, greened under the moderate irradiance level for 72 hours, increased all plastid pigment levels except for beta-carotene. The benzyladenine plus CAP combination treatment had little effect on the LHCPII levels in the wild-type wheat. The combination treatment increased the LHCPII accumulation in the CD3 mutant of wheat by about twice that of the untreated mutant. Excess LHC pigment accumulation was promoted in each wheat line. We conclude that the regulation of LHCPII in the CD3 mutant of wheat is controlled by a posttranscriptional event. Furthermore, the accumulation of LHC bound pigments is not coupled with the accumulation of LHCPII in wheat thylakoid membranes.

Journal Article↗