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Service ~ Endophyte Testing Laboratory. Lead by A. Morrie Craig and Anita Holman. History of the Oregon Seed & Straw Industries. 1987-1991: Field burning of grass straw phase-out completed 250,000 acres down to 40,000 acres. History of the Oregon Seed & Straw Industries.
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Service ~ Endophyte Testing Laboratory Lead by A. Morrie Craig and Anita Holman
History of the Oregon Seed & Straw Industries • 1987-1991: Field burning of grass straw phase-out completed • 250,000 acres down to 40,000 acres
History of the Oregon Seed & Straw Industries • Exportation of straw begins to increase • Pollution control tax credit from OR legislature • Export of grass straw to Japan grows to 250,000 tons/year in 1991 • Seed companies intensify use of endophyte since it lessens the need for pesticides, fertilizers and water • Pushes up concentration of ergot alkaloids in straw, creating the need for clinical-related research and testing and research for a long term, proactive solution
History of the Oregon Seed & Straw Industries • 1991-1999 • Grass seed export increases over 200% (250,000 to 500,000 tons/year) • Represents 250,000 acres/year that are no longer burned • 1996: Oregon Legislature votes on money to be directed towards endophyte research at OSU
Crisis in Japan • 1998: shipments to Japan were shut down by Japanese gov’t d.t. fear of high level of endophyte toxins • Dr. Craig, seed industry and National Hay Association established the endophyte testing program and reaffirmed commitment to finding a long term solution • Reopened export to Japan • 1999-present: funding from the OR Ag Fiber Assn, state of Oregon and USDA was granted to study practical and clinical aspects of endophyte-infected forages and their effects on livestock • 2002: export increases to over 600,000 tons/year
Number of Test Requests Increasing ↑ Crisis in Japan
Tall fescue ~ Ergovaline HPLC Analysis Perennial ryegrass ~Lolitrem B HPLC Analysis
Threshold Levels for Clinical Disease (Tall fescue) *Except for mares in the last 60 to 90 days of pregnancy, when the threshold is zero.
Threshold Levels for Clinical Disease (Perennial ryegrass) *Except for mares in the last 60 to 90 days of pregnancy, when the threshold is zero.
Sample Analysis Grind → Extract → Sample Prep HPLC → Chromatogram → Analysis and Data Reduction
Analysis of Endophyte Toxins • Log in samples • Accession number and submission form • Enter into computer log and case records
Analysis of Endophyte Toxins • Grind Samples • Use a grinding mill with 0.5 mm screen • Clean between each sample • Store in freezer until analysis
Analysis of Endophyte Toxins • Schedule run • Priority • Label glassware • Weigh out run • Duplicate • Samples • Controls • Reference material • 1.00g ergovaline, 0.200g lolitrem B
Analysis of Endophyte Toxins • Add mixing solutions • Ergovaline: 10 ml CHCl3, 1 ml internal standard (ergotamine tartrate) and 1 ml 0.001 N NaOH • Lolitrem B: CHCl3:MeOH (2:1 v/v) • Cap
Analysis of Endophyte Toxins • Turn in rotorack for 18-24 hours
Analysis of Endophyte Toxins • Centrifuge samples • Pull out supernatant
Analysis of Endophyte Toxins • Extraction • Ergovaline: manifold with SPE (1.0g silica and 0.5g sodium sulfate) • Condition with CHCl3 • Add 5 ml supernatant • Wash twice with 1 ml 75% CHCl3/25% acetone • Wash with 1.5 ml MeOH • Elute with 2.5 ml MeOH
Analysis of Endophyte Toxins • Concentrate • Ergovaline: dry eluent in N2 evaporator at 50°C • Lolitrem B: dry 1.8 ml supernatant in N2 evaporator • Reconstitute • Ergovaline: 0.5 ml MeOH • Lolitrem B: 0.5 ml CHCl3:ACN (4:1 v/v) • Vortex and sonicate • Final “filter” • Ergovaline: centrifuge • Lolitrem B: centrifuge in Nanosep microcentrifuge tubes • Add this solution to amber HPLC vials
Analysis of Endophyte Toxins • Run samples on HPLC system • Program computer and auto sampler • Create sequence and load method • Make mobile phase • Warm up system and prime pump • Load vials into auto sampler • Start injections
Analysis of Endophyte Toxins • Evaluate chromatograms • Draw baselines • Look for ‘abnormal’ fingerprint • Quantify
Analysis of Endophyte Toxins • Enter results into log file • Generate client summary and certificates • Fax of phone results • Send results and billing information • File lab copy of results • Transfer completed samples to long term storage freezer Sample
Quality Control Program for the Tall Fescue and Perennial Ryegrass Toxins, Ergovaline and Lolitrem B Oregon State University College of Veterinary Medicine Dr. Craig’s Laboratory
GOAL Accurate and consistent results from the analysis of samples for ergovaline and lolitrem B between laboratories in Oregon, Missouri and Japan
NMR of Ergovaline Synthesized by Dr. Forrest Smith in December DMSO H2O
CHN Analysis of December Sample Expected Found C 57.22% 57.02% H 6.11% 6.33% N 10.11% 10.04% 2 Ergovaline + 2 Tartaric acid + H2O
Ergovaline Crystalline StandardOSU Method Ergovaline 5.6 µg/ml Ergotamine Ergotamine epimer Ergovaline epimer 2.8 µg/ml 1.12 µg/ml 0.28 µg/ml
New Quality Control Reference Material for Interlaboratory Analysis • Zero Seed • 300 ppb seed • 3300 ppb seed
Dairy Case Studies Winter 2003-2004 Chuck Estill, Shanna Ivey, Anita Holman, Jennifer Duringer, A. Morrie Craig
The Problem • Reproductive problems at four dairies in the Willamette Valley in fall-winter 2003 • cows not coming into heat as frequently • silent heats • decreased conception rates
Causes • Viral or bacterial • Dr’s Estill and Holcheck involved → exams showed no sign of pathogen involvement • Mycotoxin • screened for two dairies → negative • Something else • same innoculum used for ensiling process by all four dairies • “new” toxin…
Causes con’t • Endophyte • prolactin: no obvious trend • ergovaline and lolitrem B: low levels in hay and silage • new peak: RT = 5 minutes in EV assay • only in silage, not hay from same field • another ergot alkaloid?
mw = 60 C=12, O=16, H=1 Ergovaline mw = 533.63 Molecular formula = C29H35N5O5 MS/MS (m/z 593) of 5 Minute Peak
Taking it one step further…MS7 of 5-minute peak m/z 533 5-minute peak m/z 533
Where do we go from here? • Identify the molecule • Nuclear Magnetic Resonance Spectroscopy • How many C and H? • C,H, & N Analysis • What percent is the molecule composed of C,H, & N? • Post-incident (2004…) • Reproduction problems abated • 5 minute peak has decreased in some cases, others it is still there