Search Results - "Ralphs, M. H"

Relationship Between the Endophyte Embellisia spp. and the Toxic Alkaloid Swainsonine in Major Locoweed Species (Astragalus and Oxytropis) by Ralphs, M. H, Creamer, R, Baucom, D, Gardner, D. R, Welsh, S. L, Graham, J. D, Hart, C, Cook, D, Stegelmeier, B. L

“…Locoweeds (Astragalus and Oxytropis spp. that contain the toxic alkaloid swainsonine) cause widespread poisoning of livestock on western rangelands. There are…”
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Analysis of Swainsonine:  Extraction Methods, Detection, and Measurement in Populations of Locoweeds (Oxytropis spp.) by Gardner, Dale R, Molyneux, Russell J, Ralphs, Michael H

“…An analytical method has been developed to measure the locoweed toxin, swainsonine, in locoweed plant material. Dry ground plant samples were extracted using a…”
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Distribution of norditerpene alkaloids in tall larkspur plant parts through the growing season by RALPHS, M. H, GARDNER, D. R

“…Previous research showed that toxic and total alkaloid pools in tall larkspur (Delphinium barbeyi) increased during early growth, then declined precipitously…”
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Conditioning cattle to graze broom snakeweed (Gutierrezia sarothrae) by Ralphs, M. H, Wiedmeier, R. D

“…Broom snakeweed (Gutierrezia sarothrae) is the most widespread range weed in North America. We attempted to positively condition cattle to graze broom…”
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Locoweed (Oxytropis sericea)-induced Lesions in Mule Deer (Odocoileius hemionus) by Stegelmeier, B. L, James, L. F, Gardner, D. R, Panter, K. E, Lee, S. T, Ralphs, M. H, Pfister, J. A, Spraker, T. R

“…Locoweed poisoning has been reported in wildlife, but it is unknown whether mule deer (Odocoileius hemionus) are susceptible. In areas that are heavily…”
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Predicting toxicity of tall larkspur (Delphinium barbeyi): Measurement of the variation in alkaloid concentration among plants and among years by RALPHS, M. H, GARDNER, D. R, TURNER, D. L, PFISTER, J. A, THACKER, E

“…Tall larkspur (Delphinium barbeyi) is the principal mountain larkspur responsible for the majority of cattle deaths on mountain rangelands in western Colorado…”
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Conditioning taste aversions to locoweed (Oxytropis sericea) in horses by Pfister, J. A, Stegelmeier, B. L, Cheney, C. D, Ralphs, M. H, Gardner, D. R

“…Locoweed (Oxytropis sericea) is a serious poisoning problem for horses grazing on infested rangelands in the western United States. Our objectives were to…”
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Distribution of locoweed toxin swainsonine in populations of Oxytropis lambertii by RALPHS, M. H, WELSH, S. L, GARDNER, D. R

“…Oxytropis lambertii has been considered to be one of the major locoweeds responsible for livestock poisoning on rangelands, but there has been much confusion…”
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A functional explanation for patterns of norditerpenoid alkaloid levels in Tall Larkspur (Delphinium barbeyi) by RALPHS, M. H, GARDNER, D. R, PFISTER, J. A

“…Concentrations of norditerpenoid alkaloids vary among larkspur (Delphinium) species, locations, and years, but environmental stresses seem to have little…”
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Larkspur poisoning: toxicology and alkaloid structure–activity relationships by Panter, K.E, Manners, G.D, Stegelmeier, B.L, Lee, S, Gardner, D.R, Ralphs, M.H, Pfister, J.A, James, L.F

“…Systematic approaches to taxonomic classifications of the tall larkspur spp. have been developed using traditional chemical methods to profile alkaloids,…”
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Influence of defoliation on toxic alkaloid concentration and alkaloid pools in tall larkspur by RALPHS, M. H, GARDNER, D. R

“…This study was replicated at two locations in the mountains of central Utah. In 1997, ten uniform plants of tall larkspur (Delphinium barbeyi) in the early bud…”
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Tall larkspur ingestion : Can cattle regulate intake below toxic levels? by PFISTER, J. A, PROVENZA, F. D, MANNERS, G. D, GARDNER, D. R, RALPHS, M. H

“…Tall larkspur (Delphinium barbeyi) is a toxic forb often consumed by cattle on mountain rangelands, with annual fatalities averaging about 5%. This study…”
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Influence of light and photosynthesis on alkaloid concentration in larkspur by Ralphs, M.H. (USDA, ARS, Poisonous Plant Laboratory, Logan, UT.), Manners, G.D, Gardner, D.R

“…Concentrations of toxic norditerpenoid alkaloids vary greatly in tall larkspur (Delphinium barbeyi) and may be influenced by environmental stress. We evaluated…”
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Transmission of the locoweed endophyte to the next generation of plants by Ralphs, M.H., Cook, D., Gardner, D.R., Grum, D.S.

“…Locoweed species of the legume genera Astragalus and Oxytropis (Fabaceae) contain the toxic alkaloid swainsonine, and poison livestock in semi-arid regions…”
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Effects of energy source and food flavor on conditioned preferences in sheep by Ralphs, M.H. (USDA, ARS Poisonous Plant Research Lab., Logan, UT.), Provenza, F.D, Wiedmeier, R.D, Bunderson, F.B

“…Livestock and range managers would have a powerful tool to direct utilization and modify plant communities if animals could be conditioned to eat specific…”
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Genetic variation within and among 22 accessions of three tall larkspur species ( Delphinium spp.) based on RAPD markers by Li, X, Ralphs, M.H, Gardner, D.R, Wang, R.R.-C

“…Random amplified polymorphic DNA (RAPD) markers were used to assess genetic diversity in three species of toxic larkspurs ( Delphinium spp). A total of 184…”
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Influence of cattle age, lithium chloride dose level, and food type in the retention of food aversions by Ralphs, M. H, Cheney, C. D

“…The influences of animal age and lithium chloride (LiCl) dose levels were evaluated in forming and retaining food aversions to licorice-flavored alfalfa…”
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Locoweeds: effects on reproduction in livestock by Panter, K E, James, L F, Stegelmeier, B L, Ralphs, M H, Pfister, J A

“…Locoweeds (species of Oxytropis and Astragalus containing the toxin swainsonine) cause severe adverse effects on reproductive function in livestock. All…”
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Alkaloid levels in Duncecap ( Delphinium occidentale) and Tall larkspur ( D. barbeyi) grown in reciprocal gardens: separating genetic from environmental influences by Ralphs, Michael H, Gardner, Dale R

“…The objective of this study was to determine whether differences in toxicity between Tall larkspur ( Delphinium barbeyi) and Duncecap larkspur ( D…”
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Velvet Lupine (Lupinus leucophyllus) Population Cycles with Precipitation by Ralphs, M.H., Motteram, E., Panter, K.E.

“…Velvet lupine (Lupinus leucophyllus Dougl. ex Lindl) contains the teratogenic alkaloid anagyrine that causes a crooked calf syndrome. An outbreak of crooked…”
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