Fescue Toxicosis: Can Domperidone Therapy Help Agalactic Mares in Japan?

Presented by: Chelsea Herron

Grass can harm a horse?

•Lynn Klimas Petr–Founder of STAR (Therapeutic Riding Center)

–My riding instructor•Fescue Toxicosis–Endophyte–2ndary Metabolites

http://www.metropulse.com/stories/people-you-should-know/lynn-klimas-petr-knoxvilles-therapeutic-riding-exp

What did you say?

http://www.classichorse.com/classic-horse-clip-art/classic-horse-cartoon-clip-art/confused-2/

Can I avoid it?

• 2011: Over 35 million acres in USA

– Primary forage for ≈700,000 horses

• Cut the Grass

• Try Replacing

• Highly Competitive

Symptoms of Fescue Toxicosis

I. AgalactiaII. Prolonged GestationIII. Placental Wall ThickeningIV. Dystocia http://www.emcocala.com/Fetal

%20Malposture%20and%20Dystocia.html

What is an endophyte?

• Arbuscular Mycorrhiza

– Neotyphodium coenophialum

• Plant Friendly

– Efficient nutrient absorbance

– Defense against biotic & abiotic stresshttp://planthealthproducts.com/category/mycorrhizae/

What’s the big deal with Alkaloids?

• Ergovaline

– Agonist

– D₂-Dopamine receptors Ergot Alkaloid Ergovaline

Estrogen hormone

How much does it take?

• Negative Effect Level

– 0.05 mg/kg = Agalactia

• Plant Body

– 0.2-0.6mg/kg

• Seed Head

– > 1 mg/kg

The Endophyte Life Cycle

The Endocrine Disruptive Effects of Ergopeptine Alkaloids on Pregnant Mares

Tim J. EvansPublished by Elsevier Inc. 2011

PRL & PRG Concentrations

Prog

este

rone

(ng/

ml)

Domperidone

• Antagonist

– D₂-Dopamine receptors

– Pushes Bromocriptine Out

– Ergovaline Moves In

Domperidone Therapy

Changes in Serum Concentrations of Prolactin, Progestagens, and Estradiol-17ß and Biochemical Parameters During

Peripartum in an Agalactic Mare

Kenji Korosue et al.Published by Elsevier Inc. 2013

Agalactic Mares in Japan

• Could it be Fescue Toxicosis?

– Domperidone Therapy

– Compare Hormone Levels

PRL vs. PRG Concentrations in Agalactic Mare

What is the culprit?

• Lack of symptoms

• Different Pathology

• More Information Necessary

You got a cure yet

Doc?

https://cometscorners.files.wordpress.com/2012/04/sick-horse.jpg

ReferencesEvans, T. J. (2011). The Endocrine Disruptive Effects of Ergopeptine Alkaloids on

Pregnant Mares. Veterinary Clinics of North America: Equine Practice, 165-173.Herron, C. (2015). Fescue Toxicosis: Disruption of Pregnant Mare Endocrine

Systems by Ergopeptine Alkaloids. Senior Honors Thesis.

Korosue, K., Murase, H., Sato, F., Ishimaru, M., Watanabe, G., Harada, T., . . . Nmabo, Y. (2013). Changes in Serum Concentrations of Prolactin, Progestagens, and Estradiol-17ß and Biochemical Parameters During Peripartum in an Agalactic Mare. Journal of Equine Veterinary Science, 279-286.

Neotyphodium coenophialum. (2012, December 21). Retrieved March 23, 2015, from Microbe Wiki: https://microbewiki.kenyon.edu/index.php/Neotyphodium_coenophialum

Nevala, R. (2001). Isoflavones. Effects of genistein and daidzein on arterial tone and blood pressure in rats.

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