THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE - PowerPoint PPT Presentation

emily
the effects of dietary clover species on reproduction in the ewe l.
Skip this Video
Loading SlideShow in 5 Seconds..
THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE PowerPoint Presentation
Download Presentation
THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE

play fullscreen
1 / 24
Download Presentation
THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE
180 Views
Download Presentation

THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. THE EFFECTS OF DIETARY CLOVER SPECIES ON REPRODUCTION IN THE EWE LACEY BEAM DEPARTMENT OF ANIMAL SCIENCES OREGON STATE UNIVERSITY

  2. BACKGROUND Escalon, CA

  3. BACKGROUND • SAN JOAQUIN DELTA COLLEGE 2000-2002 • OREGON STATE UNIVERSITY • B.S. IN ANIMAL SCIENCE 2004 • OREGON STATE UNIVERSITY • M.Ag. GRADUATE STUDENT

  4. REPRODUCTION • REPRODUCTIVE DIFFICULTIES IN SHEEP GRAZING CLOVER SPECIES WERE FIRST RECOGNIZED IN 1946 (Bennetts et al.) • “CLOVER DISEASE” • SYNDROME OF ABNORMAL REPRODUCTIVE FUNCTIONS OF EWES GRAZING CLOVER PASTURES

  5. GRAZING • LEGUMES ARE A WIDELY AVAILABLE FEEDSTUFF FOR MAINTAINING RUMINANT ANIMALS • SHEEP ARE A USEFUL TOOL IN A GRAZING SYSTEM • SEED TO SOIL CONTACT • CREATES MORE TILLARS • CONTROLS PLANT SIZE • INEXPENSIVE FERTILIZER • LEGUMES ARE HIGH IN CP, DIGESTIBILITY, INTAKE

  6. CLOVER SPECIES • SUBTERRANEAN CLOVER Trifolium subterraneum

  7. CLOVER SPECIES • RED CLOVER Trifolium pratense

  8. PHYTOESTROGENS • DEFINITION: COMPOUND THAT EXERTS ESTROGENIC EFFECTS ON THE CNS, INDUCE ESTRUS, AND STIMULATE GROWTH OF THE GENITAL TRACT OF FEMALE ANIMALS • CONTAINED IN MANY LEGUMES • ESTROGENIC ACTIVITY DEPENDS ON POSITION OF 2 HYDROXYL GROUPS

  9. PHYTOESTROGENS • PHYTOESTROGEN CONTENT VARIES BETWEEN PLANT SPECIES, AND GROWING AND HARVESTING CONDITIONS • EARLY SPRING: • PLANT STRESS DUE TO CHANGES IN AVAILABLE NITROGEN OR PHOSPHORUS • TEMPERATURE • DISEASE • DROUGHT • INCREASES PHYTOESTROGEN ACCUMULATION IN LEAVES

  10. PHYTOESTROGENS • PHYTOESTROGENS CONTAIN ESTROGENIC COMPOUNDS: COUMESTANS ISOFLAVONES LIGNANS

  11. PHYTOESTROGENS COUMESTANS • COUMESTROL • MOST COMMON COUMESTAN • MOST ESTROGENIC POTENCY OF ALL PHYTOESTROGENS (ADAMS, 1995a)

  12. PHYTOESTROGENS ISOFLAVONES • FORMONONETIN • MOST IMPORTANT ISOFLAVONE PERTAINING TO RUMINANTS • REDUCED AND DEMETHYLATED INTO THE MORE ESTRTOGENIC COMPOUND EQUOL (Lundh, 1990)

  13. MORE ESTROGENIC THAN FORMONONETIN RAPIDLY ABSORBED THROUGH RUMINAL WALL MAJOR ESTROGENIC METABOLITE THAT INITIATES ESTROGENIC EFFECTS IN SHEEP CHEMICAL STRUCTURE RESEMBLES ESTRADIOL - ALLOWS BINDING TO THE ESTROGEN RECEPTOR EQUOL (Lundh, 1990) (ADAMS, 1995a) Equol Estradiol

  14. DEGREDATION AND DETOXIFICATION OF ISOFLAVONES TAKES PLACE IN THE RUMEN RESULTING IN ESTROGENIC RUMEN CONTENTS RUMEN MICROBES BREAKDOWN ALL OTHER ISOFLAVONES INTO THEIR NONESTROGENIC METABOLITES FORMONONETIN EQUOL RUMINANTS AND ISOFLAVONES

  15. EFFECTS ON SHEEP • EWE INFERTILITY TEMPORARY: • DECREASED FIRST SERVICE CONCEPTION • IRREGULAR ESTRUS • DECREASED OVARIAN WEIGHTS • EXCESSIVE SMALL AND MEDIUM FOLLICLES DEFICIENT OF ANTRUM FORMATION, EARLY ATRESIA • REDUCED OVULATION AND CONCEPTION RATES • REDUCED LAMBING RATES AND MULTIPLE BIRTHS

  16. EFFECTS ON SHEEP PERMANENT: • REPEATED GRAZING: • DECREASES RESPONSIVENESS TO ESTROGEN • BARRENNESS • CERVIX- SERVES AS A RESERVOIR FOR SPERM DURING INSEMINATION AND OVULATION

  17. EFFECTS ON SHEEP • PROLONGED EXPOSURE TO ESTROGEN LEADS TO DEFEMINIZATION OF CERVIX • BECOMES SHORTER AND BROADER • INAPPROPRIATE MUCUS VISCOSITY UNABLE SPERM TO MIGRATE THROUGH CERVIX • LOSS OF ABILITY TO STORE SPERMATOZOA

  18. MEASUREMENTS OF ESTROGENIC FEEDS • UDDER DEVELOPMENT AND MILK SECRETION IN UNBRED EWES • WETHERS MAY ALSO SECRETE MILK • INCREASED TEAT LENGTH • DIRECTLY CORRELATED TO CONCENTRATIONS OF FORMONONETIN IN PASTURE

  19. ADDITIONAL PROBLEMS • DYSTOCIA • UTERINE PROLAPSE • ABORTIONS • NEONATAL MORTALITY

  20. RESEARCH • RESEARCH PAPER • AREAS OF INTEREST • SUBTERRANEAN CLOVER CAN ACCUMULATE UP TO 5% WEIGHT OF ISOFLAVONES • ISOFLAVONES ARE ONLY PRESENT IN GREEN CLOVER (ADAMS, 1995a) • RAPIDLY DRIED HAY MAY RETAIN ISOFLAVONE CONCENTRATIONS

  21. RESEARCH • OBJECTIVES • TO DEFINE RAPIDLY DRIED HAY VS. SLOWLY DRIED HAY • TO DETERMINE THE DIFFERENCES IN ISOFLAVONE LEVELS BETWEEN RAPIDLY AND SLOWLY DRIED CLOVER HAY • TO DETERMINE IF CUTTING AND HARVESTING CLOVER FOR EWE FEED HAS A NEGATIVE IMPACT ON REPRODUCTION

  22. RESEARCH • HYPOTHESIS • FEEDING SLOWLY DRIED CLOVER HAY TO EWES WILL HAVE LOWER CONCENTRATIONS OF ISOFLAVONES AND LESS NEGATIVE REPRODUCTIVE EFFECTS THAN THE SAME GRAZED CULTIVAR

  23. EXPECTED OUTCOMES • SLOWLY DRIED CLOVER HAY WILL CONTAIN LOWER LEVELS OF ISOFLAVONES THAN RAPIDLY DRIED CLOVER HAY • NEGATIVE REPRODUCTIVE EFFECTS ON THE EWE SHOULD BE REDUCED COMPARED TO GRAZED GREEN CLOVER • SPECIFIC EVENTS DURING THE DRYING PROCESS THAT REDUCES/ELIMINATE ISOFLAVONE CONCENTRATIONS

  24. QUESTIONS? THANK YOU