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PubMed1966

Metabolic changes associated with vernalization of wheat. I. Carbohydrate and nitrogen patterns.

A spring wheat (Triticum aestivum) and an obligate winter wheat (Triticum compactum) variety were each grown for 5 weeks in controlled environments at 2 degrees and 25 degrees . The threshold for flower induction in the winter wheat was 4 to 5 weeks at 2 degrees , whereas the spring wheat had no low temperature requirement for flowering. Changes in the levels of carbohydrate and nitrogen fractions in the wheat leaves were determined during their growth in the cold and warm environments. There was an enhanced accumulation of the 5 carbohydrate fractions in both wheat varieties grown at 2 degrees compared to 25 degrees . Highly significant differences in the levels of sucrose, oligosaccharides, and starch were found between the spring and winter varieties grown at 2 degrees . The winter wheat seedlings grown at 2 degrees accumulated much more of these carbohydrates than the corresponding spring wheat. The carbohydrate patterns in both varieties grown at 25 degrees were nearly identical except for the final 2 weeks of growth.The level of nitrogenous substances in the tissues grown at 2 degrees was much higher than in the corresponding tissues grown at 25 degrees . The only significant difference between the spring and winter varieties was in the soluble protein fraction. This fraction rose nearly 3-fold in the winter variety grown at 2 degrees , whereas it remained nearly constant in the similarly grown spring wheat. Most of the changing chemical patterns observed in relation to the vernalization treatment appear to be metabolic alterations associated with low temperature rather than alterations directly related with the vernalization response.

Journal Article↗
PubMed2006

Effects of level of feed intake and Fusarium toxin-contaminated wheat on rumen fermentation as well as on blood and milk parameters in cows.

The aims of this study were to examine the effects of and possible interactions between dry matter (DM) intake and feeding Fusarium toxin-contaminated wheat on ruminal fermentation, serum chemical parameters and milk yield of dairy cows. Fourteen dairy cows equipped with ruminal and duodenal cannulas were analysed. All animals were fed the same ration, the daily feed amounts being adjusted to current performance. On DM basis, the ration consisted of 60% concentrate including 55% wheat [Fusarium-contaminated wheat (mycotoxin period) or control wheat (control period)] and was completed with 40% maize and grass silage. Each cow was fed the contaminated wheat [deoxynivalenol (DON), 8.21 mg/kg DM and zearalenone (ZON), 0.09 mg/kg DM] and the control wheat (0.25 mg DON/kg DM and 51 microg ZON/kg DM). As expected, a higher organic matter (OM) intake decreased the amounts of fermented crude nutrients related to the respective intakes. An increased amount of crude protein degraded (p < 0.05) and a lower molar percentage of propionate in the rumen fluid were observed when feeding the Fusarium toxin-contaminated wheat at increased OM intakes in comparison with the control wheat. The activities of serum aspartate aminotransferase (ASAT; p < 0.001), glutamate dehydrogenase (GLDH; p < 0.01) and gamma glutamyl transferase (gamma-GT; p < 0.01) increased with increasing OM intake and were not related to the mycotoxin contamination of the wheat.

Animal Feed↗
PubMed2004

Changes in population structure of the soilborne fungus Gaeumannomyces graminis var. tritici during continuous wheat cropping.

A method was developed to assess the genetic structure of Gaeumannomyces graminis var. tritici (Ggt) populations and test the hypothesis of an association between disease level in the field with changes in pathogen populations. A long-term wheat monoculture experiment, established since 1994, generated different take-all epidemics with varying the number of wheat crop successions in the 1999-2000 cropping season. Genetic polymorphism in Ggt populations was investigated over natural, local epidemics. Four populations of 30 isolates were isolated from necrotic wheat roots in a first, third, fourth, and sixth wheat crop in the same year. Each Ggt isolate was characterized with RAPD (Random Amplification Polymorphism DNA) markers and AFLP (Amplified Fragment Length Polymorphism) fingerprinting. Seventeen multilocus genotypes based on the combination of RAPD and AFLP markers were identified among all these populations. The 120 isolates were divided into two main groups, G1 and G2, according to bootstrap values higher than 86%, except for an unique isolate from the third wheat crop. Within each group, populations ranged between 93 and 100% similarity. Both groups included isolates collected from the first, third, fourth or sixth wheat crop. However, G1 group profiles dominated amongst isolates sampled in the first and the sixth wheat crops, whereas G2 group profiles largely dominated amongst isolates collected from the third and fourth wheat crops. Aggressiveness of group G2 (38%) was significantly greater than that of G1 (29.5%). These results suggest that changes in Ggt population structure occur during continuous wheat cropping. The distinction of two Ggt groups provides a simple basis for further spatio-temporal analysis of Ggt population during polyetic take-all decline.

Ascomycota↗
PubMed1997

Induced Reporter Gene Activity, Enhanced Stress Resistance, and Competitive Ability of a Genetically Modified Pseudomonas fluorescens Strain Released into a Field Plot Planted with Wheat.

The fates of Pseudomonas fluorescens R2fR and its mutant derivative RIWE8, which contains a lacZ reporter gene responsive to wheat root exudate, were compared in a field microplot. Inoculant survival, root colonization, translocation, resistance to stress factors, and reporter gene activity were assessed in bulk and wheat rhizosphere soils. Populations of both strains declined gradually in bulk and wheat rhizosphere soils and on the wheat rhizoplane as determined by specific CFU and immunofluorescence (IF). In samples from both bulk soil and wheat rhizosphere, IF cell counts were up to 3 orders of magnitude greater than the corresponding numbers of CFU after 120 days, indicating the presence of nonculturable inoculant cells. Estimates of RIWE8-specific target DNA molecule numbers in bulk soil samples 3 and 120 days after inoculation by most-probable-number PCR coincided with the corresponding CFU values. Transport of both strains to deeper soil layers was observed by 3 days after introduction into the microplot. Both strains colonized wheat roots similarly, and cells were seen scattered on the surface of 1-month-old wheat seedling roots by immunogold labelling-scanning electron microscopy. On average, reporter gene activity was significantly higher in wheat rhizosphere soil containing RIWE8 cells than in bulk soil or in soils containing R2fR cells. For both strains, resistance to the four stress factors ethanol, high temperature, high osmotic tension, and oxidative stress increased progressively with residence in soil. Cells from the rhizosphere of 11-day-old seedlings showed similar levels of resistance to osmotic and oxidative stresses and enhanced resistance to ethanol and heat as compared to cells from bulk soil. By 37 days, populations of R2fR and RIWE8 in the rhizosphere were significantly more sensitive to osmotic stress than were populations in bulk soil, whereas differences in response to the other stress factors were less evident. Hence, except for the induction of reporter gene expression in strain RIWE8 in the wheat rhizosphere, the data indicated that there were no great differences in the ecological properties in soil between the lacZ-modified and parental strains.

Journal Article↗
PubMed2006

Use of a large-scale Triticeae expressed sequence tag resource to reveal gene expression profiles in hexaploid wheat (Triticum aestivum L.).

The US Wheat Genome Project, funded by the National Science Foundation, developed the first large public Triticeae expressed sequence tag (EST) resource. Altogether, 116,272 ESTs were produced, comprising 100,674 5' ESTs and 15 598 3' ESTs. These ESTs were derived from 42 cDNA libraries, which were created from hexaploid bread wheat (Triticum aestivum L.) and its close relatives, including diploid wheat (T. monococcum L. and Aegilops speltoides L.), tetraploid wheat (T. turgidum L.), and rye (Secale cereale L.), using tissues collected from various stages of plant growth and development and under diverse regimes of abiotic and biotic stress treatments. ESTs were assembled into 18,876 contigs and 23,034 singletons, or 41,910 wheat unigenes. Over 90% of the contigs contained fewer than 10 EST members, implying that the ESTs represented a diverse selection of genes and that genes expressed at low and moderate to high levels were well sampled. Statistical methods were used to study the correlation of gene expression patterns, based on the ESTs clustered in the 1536 contigs that contained at least 10 5' EST members and thus representing the most abundant genes expressed in wheat. Analysis further identified genes in wheat that were significantly upregulated (p < 0.05) in tissues under various abiotic stresses when compared with control tissues. Though the function annotation cannot be assigned for many of these genes, it is likely that they play a role associated with the stress response. This study predicted the possible functionality for 4% of total wheat unigenes, which leaves the remaining 96% with their functional roles and expression patterns largely unknown. Nonetheless, the EST data generated in this project provide a diverse and rich source for gene discovery in wheat.

Cluster Analysis↗
PubMed1996

A PCR assay for detection of a 2RL.2BS wheat-rye chromosome translocation.

A 2RL.2BS wheat-rye translocation, present in the wheat germplasm line Hamlet, carries a gene for resistance to Hessian fly biotype L, one of the most virulent biotypes presently encountered in wheat production environments. Unlike several other wheat-rye chromosome translocations common in wheat breeding programs, 2RL lacks genes encoding storage proteins or other easily selected markers. Oligonucleotide primers synthesized from published sequences derived from the R173 family of moderately repetitive rye DNA were used in the DNA polymerase chain reaction (PCR) to identify specific markers for 2RL. The same primers, when used with DNA extracted from additional wheat-rye translocation lines of importance to the wheat breeding community, gave distinctive PCR products for each genotype. The single primer pair, PAWS5 and PAWS6, may, therefore, have wide applicability for the identification of wheat-rye chromosomal translocations presently encountered in wheat breeding populations.

Base Sequence↗
PubMed1998

Comparative mapping of the two wheat leaf rust resistance loci Lr1 and Lr10 in rice and barley.

The wheat genome is large, hexaploid, and contains a high amount of repetitive sequences. In order to isolate agronomically important genes from wheat by map-based cloning, a simpler model of the genome must be used for identifying candidate genes. The objective of this study was to comparatively map the genomic regions of two wheat leaf rust disease resistance loci, Lr1 and Lr10, in the putative model genomes of rice and barley. Two probes cosegregating with the Lr1 gene on chromosome 5DL of wheat were studied. The rice sequences corresponding to the two probes were isolated and mapped. The two probes mapped to two different rice chromosomes, indicating that the organization of the region orthologous to Lr1 is different in rice and wheat. In contrast, synteny was conserved between wheat and barley in this chromosomal region. The Lrk10 gene cosegregated with Lr10 on chromosome 1AS in wheat. The rice gene corresponding to Lrk10 was mapped on rice chromosome 1, where it occurred in many copies. This region on rice chromosome 1 corresponds to the distal part of the group 3S chromosomes in Triticeae. The synteny is conserved between rice chromosome 1 and the Triticeae group 3S chromosomes up to the telomere of the chromosomes. On group 3S chromosomes, we found a gene that is partially homologous to Lrk10. We conclude that in the genomic regions studied, there is limited and only partially useful synteny between wheat and rice. Therefore, barley should also be considered as a model genome for isolating the Lr1 and Lr10 genes from wheat.

Base Sequence↗
PubMed2005

Characterization of derivatives from wheat-Thinopyrum wide crosses.

Partial amphiploids are lines that contain 42 (38-42) wheat and 14 (14-18) alien chromosomes. They are derived by backcrossing wheat onto hybrids between wheat and either Thinopyrum intermedium (6x) or Th. ponticum (10x). GISH analysis has shown that, with possibly one exception, the alien genomes (chromosome sets) in partial amphiploids are found to be hybrids i.e. composed of chromosomes from more than one alien genome. The individual partial amphiploids are meiotically stable and nearly perfectly fertile, but hybrids between different lines were characterized by varying numbers of unpaired chromosomes and consequently variable degrees of sterility. Translocated chromosomes involving different Thinopyrum genomes or Thinopyrum and wheat genomes were found in partial amphiploids and consequently in the addition lines derived from them. Partial amphiploids have proven to be an excellent tertiary gene pool for wheat improvement, containing resistance to biotic stresses not present in wheat itself. Resistance to Barley Yellow Dwarf Virus (BYDV) and Wheat Streak Mosaic Virus (WSMV) have been found in partial amphiploids and addition lines derived from both Th. intermedium and Th. ponticum. Excellent resistance to Fusarium head blight has been found on a Th. intermedium chromosome that had substituted for chromosome 2D in wheat. Genes for resistance to leaf rust and stem rust have already been incorporated into wheat and tagged with molecular markers.

Chromosomes, Plant↗
PubMedDate not supplied

Wheat bran decreases aberrant crypt foci, preserves normal proliferation, and increases intraluminal butyrate levels in experimental colon cancer.

BACKGROUND: Dietary wheat bran protects against colon cancer, but the mechanism(s) of this effect is not known. Butyrate, produced by colonic bacterial fermentation of dietary polysaccharides, such as wheat bran, induces apoptosis and decreases proliferation in colon cancer cell lines. Whether similar effects occur in vivo is not well defined. We hypothesized that wheat bran's antineoplastic effects in vivo may be mediated in part by butyrate's modulation of apoptosis and proliferation. METHODS: Male F344 rats were fed wheat bran-supplemented or an isocaloric, isonitrogenous fiber-free diet. Rats were treated with one dose of the carcinogen azoxymethane or vehicle with sacrifice after 5 days (tumor initiation); or two doses (days O and 7) with sacrifice after 56 days (tumor promotion). Study variables included fecal butyrate levels and the intermediate biomarkers of colon carcinogenesis, aberrant crypt foci (ACF), and changes in crypt cell proliferation and apoptosis. RESULTS: During tumor initiation, wheat bran produced greater apoptosis (p = .01), a trend toward less proliferation, and preserved the normal zone of proliferation (p = .01). At tumor promotion, wheat bran decreased the number of ACF (proximal colon, p = .005; distal colon, p = .047) and maintained the normal proliferative zone. The fiber-free diet shifted the zone of proliferation into the premalignant pattern in both studies. Wheat bran produced significantly higher fecal butyrate (p = .01; .004, .00001) levels than the fiber-free diet throughout the tumor promotion study. CONCLUSIONS: Wheat bran increased apoptosis and controlled proliferation during tumor initiation and resulted in decreased ACF. Wheat bran's antineoplastic effects occurred early after carcinogen exposure, and were associated with increased fecal butyrate levels.

Animals↗
PubMed2004

Lysine fortification of wheat flour improves selected indices of the nutritional status of predominantly cereal-eating families in Pakistan.

Wheat provides more than 50% of the protein and calorie intake of the population of Pakistan. Legumes and animal protein that could complement the amino acid pattern of wheat, in which lysine is the first limiting amino acid for utilization of protein, are not affordable by members of lower socioeconomic groups in developing countries. The purpose of the study was to determine whether lysine fortification of wheat flour would have a positive impact on populations consuming a predominantly wheat-based diet. A double-blind study was carried out for three months on the outskirts of Peshawar, Pakistan. Forty families received wheat flour fortified with lysine, and 40 families received wheat flour without lysine. Wheat provided 59% of the protein for men, 65% for women, and 58% for children. The weight and height of the children in both groups increased during the study, but the increase was significantly greater in the lysine group. Hemoglobin increased significantly in the women receiving lysine-fortified flour. Transferrin levels increased significantly in men, women, and children in the lysine group as compared with those in the control group. Prealbumin increased significantly in adults receiving additional lysine but decreased in children. Men, women, and children in the lysine-supplemented families had significant increases in CD4, CD8, and complement C3 as compared with controls. These results indicate that lysine fortification of wheat flour can significantly improve sensitive indicators of nutritional status in a population consuming a diet in which 58% to 65% of the protein, depending on age and sex, is supplied by wheat.

Adult↗
PubMed2004

Sequence polymorphism in polyploid wheat and their d-genome diploid ancestor.

Sequencing was used to investigate the origin of the D genome of the allopolyploid species Triticum aestivum and Aegilops cylindrica. A 247-bp region of the wheat D-genome Xwye838 locus, encoding ADP-glucopyrophosphorylase, and a 326-bp region of the wheat D-genome Gss locus, encoding granule-bound starch synthase, were sequenced in a total 564 lines of hexaploid wheat (T. aestivum, genome AABBDD) involving all its subspecies and 203 lines of Aegilops tauschii, the diploid source of the wheat D genome. In Ae. tauschii, two SNP variants were detected at the Xwye838 locus and 11 haplotypes at the Gss locus. Two haplotypes with contrasting frequencies were found at each locus in wheat. Both wheat Xwye838 variants, but only one of the Gss haplotypes seen in wheat, were found among the Ae. tauschii lines. The other wheat Gss haplotype was not found in either Ae. tauschii or 70 lines of tetraploid Ae. cylindrica (genomes CCDD), which is known to hybridize with wheat. It is concluded that both T. aestivum and Ae. cylindrica originated recurrently, with at least two genetically distinct progenitors contributing to the formation of the D genome in both species.

Base Sequence↗
PubMed2004

Comparison of aeration and spinosad for suppressing insects in stored wheat.

Field studies were conducted from July 2002 to January 2003 for evaluating the effects of controlled aeration and a commercial biological insecticide, spinosad, in suppressing insect populations in stored wheat. Six cylindrical steel bins were filled with newly harvested (2002 crop year) hard red winter wheat on 9 and 10 July 2002. Each bin contained 30.7 metric tons (1,100 bu) of wheat. Wheat in two bins was left untreated (control), whereas wheat in two bins was treated with spinosad, and in another two bins was subjected to aeration by using aeration controllers. Spinosad was applied to wheat at the time of bin filling to obtain a rate of 1 mg ([AI])/kg. Aeration controllers were set to run the fans when ambient air temperature fell below 23.9, 18.3, and 7.2 degrees C for the first, second, and third cooling cycles, respectively. We added 400 adults each of the rusty grain beetle, Cryptolestes ferrugineus (Stephens); lesser grain borer, Rhyzopertha dominica (F.); and red flour beetle, Tribolium castaneum (Herbst), to the grain at monthly intervals between July and October 2002. Insect density in the bins was estimated monthly by taking 3-kg grain samples from 21 locations within each bin by using a pneumatic grain sampler. No live T. castaneum or C. ferrugineus and very low densities of R. dominica (<0.008 adults per kilogram) were found in wheat treated with spinosad during the 6-mo sampling period. Density of C. ferrugineus and T. castaneum in aerated bins did not exceed two adults per kilogram (the Federal Grain Inspection Service standard for infested wheat), whereas R. dominica increased to 12 adults per kilogram in November 2002, which subsequently decreased to three adults per kilogram in January 2003. In the untreated (control) bins, R. dominica density increased faster than that of C. ferrugineus or T. castaneum. Density of R. dominica peaked at 58 adults per kilogram in October 2002 and decreased subsequently, whereas T. castaneum density was 10 adults per kilogram in October 2002 but increased to 78 adults per kilogram in January 2003. Density of C. ferrugineus increased steadily during the 6-mo study period and was highest (six adults per kilogram) in January 2003. This is the first report comparing the field efficacy of spinosad and aeration in managing insects in farm bins. Our results suggest that spinosad is very effective in suppressing R. dominica, C. ferrugineus, and T. castaneum populations in stored wheat.

Animals↗
PubMed2001

Deep rooting in winter wheat: rooting nodes of deep roots in two cultivars with deep and shallow root systems.

Deep rooting of wheat has been suggested that it influences the tolerance to various environmental stresses. In this study, the nodes from which the deepest penetrated roots had emerged were examined in winter wheat. The wheat was grown in long tubes with or without mechanical stress and in large root boxes. The length and growth angle of each axile root were examined to analyze the difference in the vertical distribution of the roots between the two wheat cultivars, one with a deep and one with a shallow root system. In Shiroganekomugi, a Japanese winter wheat cultivar with a shallow root system, the rooting depths of the seminal and nodal roots decreased as the rooting nodes advanced acropetally. Six out of nine deepest roots were seminal root in the non-mechanical stress conditions. In Mutsubenkei, a Japanese winter wheat cultivar with a deep root system, grown in root boxes, not only the seminal roots but also the coleoptilar and the first nodal roots penetrated to a depth of more than 1.3 m in the root box, and became the deepest roots. In both cultivars, the seminal roots became the deepest roots under the mechanical stress conditions. There were no clear tendencies in the root growth angles among the rooting nodes in the wheat root system. This indicates that the length of the axile roots can explain the differences in the rooting depths among axile roots in a wheat root system. On the other hand, the axile roots of Mutsubenkei elongated significantly more vertically than those of Shiroganekomugi. This suggests that not only seminal but also nodal roots exhibit strong positive gravitropism and penetrate deeply in a cultivar with a deep root system. In wheat cultivars, it is likely that the extent of its Root Depth Index results partly from the gravitropic responses of both seminal and nodal roots.

Acclimatization↗
PubMed1999

Effect of wheat and corn variety on fiber digestion in beef steers fed high-grain diets.

Six Salers steers, fitted with ruminal and duodenal cannulas, were used in a double 3x3 Latin square design to assess the depressive effect of the nature of wheat, flint corn, and dent corn on fiber digestion in animals fed high-concentrate diets, and to determine the mechanisms involved in these negative digestive effects. Diets were balanced to be equal in starch content (47.7+/-2.3%). The three cereals were characterized by ruminal starch digestibilities of 86.6, 60.8, and 34.8% for the wheat, dent corn, and flint corn, respectively. Ruminal digestion of NDF was lower with wheat- than with corn-based diets (49.4 vs. 55.2%; P<.001), and with dent corn than with flint corn (53 vs. 57.3%; P<.01). Degradability of hay in nylon bags was not affected by the grain source in the diet (P>.1). The mean retention time of forage particles in the rumen was similar between wheat and corn diets (P>.1), but it was lower for steers fed dent corn than for those fed flint corn (P<.05). Most fibrolytic activities of the solid-associated microorganisms were lower (P<.05) in animals fed wheat than in those fed corn. Differences in fibrolytic activities of the solid-associated microorganisms between the two corn genotypes were not statistically significant (P>.1), but activities of all fibrolytic enzymes were lower (P<.05) with the dent than with the flint corn diet. Protozoal number in ruminal fluid was lower in animals receiving wheat than in those fed corn (177 vs. 789x10(3)/mL; P<.001) and was related to the high ruminal acidity (P<.01) of the wheat diet. Large modifications in the rumen microbial ecosystem between the two corn genotypes were not visible in protozoal numbers or pH. Total-tract digestion of NDF was the same for wheat and for corn diets, averaging 55% for the three diets. A postruminal compensation of NDF digestion (14% of the total tract NDF digestion) seemed to occur with the wheat diet. The lack of any postruminal NDF digestion (0%) with the two corn diets may suggest negative digestive interactions in the hindgut similar to those in the rumen.

Animal Feed↗
PubMed1989

Effects of supplemental silage on forage intake and utilization by steers grazing wheat pasture or bermudagrass.

Seven trials were conducted to determine the effects of increasing amounts of silage (corn, wheat or sorghum) on forage intake, gastrointestinal tract fill, fecal output and ruminal flow and degradation of forage by cattle grazing wheat pasture or bermudagrass. In each of 3 yr, 24 steers grazed a common wheat or bermudagrass pasture and were randomly allocated to four treatments (0, .35, .70 or 1.05 kg silage DM.100 kg body weight-1.d-1). Intake and ruminal flow of forage were measured by feeding a single pulse dose of Yb-labeled forage followed by collection of fecal samples for 4 to 5 d and fitting Yb concentrations to a one-compartment, age-dependent model. Ruminal digestion kinetics of wheat forage were estimated in situ using eight ruminally cannulated steers fed 0 or .55 kg sorghum silage DM.100 kg body weight-1.d-1. Supplemental silage decreased wheat forage (P less than .10) and bermudagrass (P less than .01) intake linearly. However, total forage intake of bermudagrass plus silage increased linearly (P less than .05). Each kilogram of added silage DM decreased DM intake of wheat forage by .66 +/- .25 and of bermudagrass by .63 +/- .17 kg. Flow and turnover of wheat forage or bermudagrass were not altered (P greater than .15) by supplemental silage. Silage consumption increased extent of ruminal degradation of wheat forage DM (P less than .05; 63.1 vs 52.5%), indicating a positive associative effect of silage on wheat forage utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1985

Ingestion of vomitoxin (deoxynivalenol)-contaminated wheat by nonlactating dairy cows.

Our objective was to determine if there were serious deleterious effects of wheat naturally contaminated with vomitoxin (deoxynivalenol) on nonlactating dairy cows. Comparisons were between two Quebec spring wheat sources contaminated with Fusarium graminearum in a feeding trial involving 10 nonlactating Holstein dairy cattle offered good quality hay for ad libitum intake supplemented with wheat-oats concentrate (1 kg concentrate/100 kg body weight). Initially, for 3 wk all cows were fed hay plus wheat-oats containing 1.5 mg vomitoxin/kg. Each week thereafter two more cows, chosen at random, were switched to a second wheat-oats concentrate containing higher mycotoxin concentration (6.4 mg vomitoxin/kg). After the last two cows had been on the latter diet for 6 wk, all cows were returned to the previous wheat-oats concentrate containing the lower mycotoxin concentration (1.5 mg vomitoxin/kg). No unusual symptoms of illness that might be attributed to the mycotoxin-contaminated wheat were observed. In body weight gains, the data reflected a linear growth pattern with no apparent effect of changing from low to high vomitoxin content in the concentrate. Generally, consumption of the wheat-oats ration containing 6.4 mg vomitoxin/kg was lower than the 1.5 mg vomitoxin/kg concentrate. The progressive, linear decrease of hay consumption was not affected by source of contaminated wheat-oats diet.

Animal Feed↗
PubMed1987

Effects of treating wheat straw with pH-regulated solutions of alkaline hydrogen peroxide on nutrient digestion by sheep.

An experiment using a 4 X 4 Latin square design was to determine effects of treating wheat straw with pH-regulated (pH = 11.5) solutions of hydrogen peroxide on site and extent of nutrient digestion in multiple-fistulated sheep. Regulating reaction pH at 11.5 prevented solubilization of some cell wall hemicelluloses, resulting in improved retention of DM. Diets fed to sheep contained 33 or 70% wheat straw either untreated or treated with alkaline hydrogen peroxide. Sheep fed diets of treated wheat straw digested more DM, NDF, ADF, and cellulose anterior to the duodenum and in the total tract than when fed diets of untreated wheat straw. Apparent CP digestion before the duodenum was highest when sheep were fed the treated 33% wheat straw diet and untreated 70% wheat straw diet. Treatments did not affect apparent nutrient digestibilities in the large intestine. Ruminal pH was lower when sheep were fed the alkaline hydrogen peroxide-treated or diets containing 33% wheat straw. Ruminal ammonia concentrations were highest when sheep were fed the untreated 70% wheat straw diet. Molar proportions of ruminal acetic and propionic acids were unaffected by diet. Alkaline hydrogen peroxide treatment substantially increased susceptibility of structural carbohydrates of wheat straw to microbial degradation in the gastrointestinal tract of sheep.

Animal Feed↗
PubMed1989

Utilization of wheat in complete rations for lactating cows.

Effects of different amounts of wheat, protected amino acids, and increased rumen escape protein in high wheat rations were evaluated in two trials with dairy cows. In trial 1, concentrate mixtures with 0, 40, or 60% hard red winter wheat were included in a complete ration with 45% sorghum silage (dry basis). Intake of DM and CP was not affected by treatment. Milk yield declined (28.8, 28.0, 27.3 kg/d) as amount of wheat in the ration increased. In a second trial, concentrate mixtures with 60% wheat were compared with a control corn-base mixture. One wheat mixture was supplemented with protected lysine and methionine and another had protected lysine and methionine plus estimated rumen escape protein equal to the control. Intake of DM and CP was not affected. Milk yield of cows fed rations containing wheat, with or without protected amino acids, was lower than that of cows fed the control ration or the wheat ration in which rumen escape protein was equal to the control (29.1 and 29.0 vs. 30.8 and 30.2 kg/d). Responses of cows fed concentrate mixtures containing wheat appeared to be related to utilization of protein.

Amino Acids↗