Laminitis research

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What is Laminitis?

Wikipedia: Laminitis:

The digital laminae are responsible for suspension of the axial skeleton of the animal within the hoof and dissipate concussive forces during locomotion. There are about 600 pairs of interleaved laminae: the epidermal laminae attached to the hoof wall and the dermal laminae attached to the coffin bone. Laminitis results from a compromise of this interaction, the mechanism of which remains unclear and is currently the subject of much research. Laminitis literally means inflammation of the laminae, and while it remains controversial whether this is the primary mechanism of disease, evidence of inflammation occurs very early in some instances of the disease.

In laminitis cases, a clear distinction must be made between the acute situation, starting at the onset of a laminitis attack and a chronic situation. A chronic situation can be either stable or unstable. The difference between acute, chronic, stable and unstable is of vital importance, when choosing a treatment protocol.

Laminitis can be mechanical or systemic, unilateral (on one foot) or bilateral (on two feet) or may also occur in all four feet.

Systemic laminitis follows from some metabolic disturbance within the horse, from a multitude of possible causes, and results in the partial dysfunction of the epidermal and dermal laminae, which attach the distal phalanx to the hoof wall. With this dysfunction, the deep digital flexor tendon (which attaches to the semi-lunar crest of the distal phalanx and serves to flex the foot) is able to pull the bone away from the wall, instead of flexing the foot. When the coffin bone is pulled away from the hoofwall, the remaining laminae will tear. This may lead to abscesses, within the hoof capsule, that can be severe and very painful.

Systemic laminitis is usually bilateral and is most common in the front feet, although it sometimes affects the hind feet.

Mechanical laminitis or "mechanical founder" does not start with laminitis or rotation of the distal phalanx. Instead, the wall is pulled away from the bone or lost, as a result of external influences. Mechanical founder can occur when a horse habitually paws, is ridden or driven on hard surfaces or loses laminar function, due to injury or pathologies affecting the wall.

Mechanical founder can be either unilateral or bilateral and can affect both front and hind feet.

a. b. c.

a) X-ray of a Laminitis hoof with rotation of coffin bone and some sinking

b) Dr Ric Redden's typical diagram when working with x-rays

c) Venogram of normal hoof

What Causes Laminitis?

Obesity is a primary predisposing factor, with some horses and breeds having a genetic susceptibility. Individuals might have efficient energy metabolism and/or nutrient digestion or absorption, or they might have an insatiable appetite. Diet and management practices that lead to obesity include overfeeding (particularly grain), lack of exercise, and varied perceptions of what is considered "good" body condition.

Equine metabolic syndrome describes a syndrome of obesity with regional fat deposits in the neck, prepuce or udder, rump, and subcutaneous tissues. There can be a genetic and/or breed predisposition coupled with insulin resistance (IR) and high risk for laminitis.

Part of the equine metabolic syndrome picture includes insulin resistance, which describes reduced response to insulin to take up glucose in the tissues (skeletal muscle, fat, and liver). Progression of obesity and insulin resistance exacerbates laminitis risk. As a horse gets fatter, insulin sensitivity decreases. Insulin resistance worsens with chronic obesity, making a horse more susceptible to laminitis and less tolerant of triggering events. The longer a horse is obese, the more other tissues are affected.

Laminitis triggers include exacerbation of an insulin resistance crisis due to increased starch and sugar in green grass or other stresses, such as diet and grain supplements, change in pasture, stress of transport, "mechanical separation" (road founder), management or weather, poor blood circulation, disease, hospitalization, and/or surgery. The crisis might be related to seasonal hormonal changes. Another trigger develops in the intestine, particularly when a horse is turned out on new pasture with a sudden increase in starches, sugars, and fructans that creates a carbohydrate overload in the large intestine. This alters bacterial flora, lowers the pH, increases intestinal permeability, and results in endotoxemia, which increases multiorgan inflammation, increases vascular constriction, and induces IR.

The following preventive strategies for avoiding these laminitis scenarios are recommended:

- Manage and treat obesity and insulin resistance;

- Treat equine Cushing's disease and monitor regularly;

- Provide consistent farrier care;

- Regulate starch, sugar, and calorie intake;

- Avoid sudden feed changes;

- Gradually introduce a horse to new pasture; and

- Treat endotoxemia and systemic inflammation.

more on "reasons" for Laminitis: AAEP 2008: Causes of Laminitis

Other possible reasons for laminitis

Who is doing the research?

International Equine Podiatry Center, Versailles, KY

Scool of Veterinary Science - The University of Queensland Headed by Professor Chris Pollitt, also in charge of Australian Equine Laminitis Research Unit

Royal Veterinary College, London

Penn Veterinary School of Medicine

What is the state of that research?

What We Know About Laminitis

Laminitis Treatment: Natural Perspective by Joyce Harman DVM and Madalyn Ward DVM

Founder: Prevention & Cure the Natural Way, 2001 by Jaime Jackson (Star Ridge Publishing) Considered to be one of the most controversial yet written on the subject AND the most useful.

Articles and studies

Various Articles on Laminitis from the International Equine Resource Center

Heparin Might Prevent Laminitis after Colic Surgery The Horse 9/27/09

Equine Metabolic Syndrome a Focus of Research The Horse 8/25/09

Hoof Radiographs The Horse 5/1/05

Laminitis risk Increased by Pasture Grass Sugars The Horse 6/29/09

Metformin a Therapy in Progress for Equine Insulin Resistance The Horse 5/25/09

Form and Function: Managing Chronic Laminitis The Horse 4/3/09

AAEP 2008: Causes of Laminitis The Horse 4/1/09

Laminitis: Cryotherapy Treatment in the Real World The Horse 3/27/09

AAEP 2008: Are Drugs Effective for Acute Laminitis? The Horse 3/18/09

Teff Hay for Foundered Horses: A Good Fit? The Horse 12/22/08

Forage Options for Special Needs Horses The Horse 11/8/08

Autumn Brings Challenges to Cushing's Diagnosis, Management The Horse 9/27/08

Diagnosing Insulin Resistance: Q&A with Researchers The Horse 8/31/08

The Science of Seasons Behind Laminitis, PPID The Horse 7/20/08

Potomac Horse Fever: Don't Ignore Fevers! The Horse 7/7/08 Potomac fever may lead to laminitis...

Inside the Laminitic Foot The Horse 7/1/08 ONE OF THE BEST ARTICLES - PLEASE READ


Managing Acute and Chronic Laminitis The 6/1/08

Wooden Shoes for Chronic Laminitis The 4/23/08

Preliminary Study Performed on New Laminitis Treatment Technique The 4/4/08

Control Spring Pasture Access The 3/31/08

Lessons from Barbaro The 3/23/08

Reducing Hindgut Acidosis The 3/17/08

Healthy Hooves, Inside and Out The Horse 3/1/08 Including "THE MYTH OF MATCHING FEET", by Dr Ric Redden

Dangerous Liaisons: Cytokines, Inflammation, and Insulin Resistance The 1/31/08

Laminitis Conference an Important Step The 12/24/07

Staving off Laminitis with a Buffer Solution The 12/23/07

Readers Respond: Diagnosing Laminitis The 12/14/07

2007 Morris Animal Foundation Equine Research Wrap-Up The 12/14/07

Illinois Vet School Reporting Cases of Black Walnut Laminitis The 12/11/07

Horse Health News Video: Ryder Report for Nov. 28 The Horse 11/28/07 VIDEO

Laminitis Pain Might Originate from Different Source The Horse 11/27/07

Insulin Levels Might Help Measure Likelihood of Laminitis The Horse 11/26/07

The Timeline of Laminitis The 11/23/07

Laminitis Conference Ramps Up the Fight Against Foot Problems in Horses The Horse 11/20/07

Couple Donates $1 Million to UPenn Laminitis Research Fund The Horse 11/15/07

Laminitis Studies Financed by Barbaro Fund to Commence The 11/8/07

Chronicling Laminitis: Horse Owner Records Every Step Toward Recovery The Horse 9/20/07 including VIDEO

Laminitis: New Study on Sugar and Starch as a Cause The 8/25/07

Understanding Laminitis On-Demand Webinar The Horse 8/11/07 VIDEO

Obesity, Insulin Resistance, and Laminitis The Horse 7/31/08

Obesity and Laminitis The Horse 7/9/07

Foot X Rays: A Crystal Ball? The Horse 6/17/07 A really good article, by Ric Redden, DVM, founder of the International Equine Podiatry Center in Versailles, Ky. - why having an educated and skilled farrier is one of the most important things, when you have a horse with Laminitis...

Finding and Testing Low-Sugar Forage The Horse 5/14/07

The Quest to Conquer Laminitis The Horse 5/1/07 ...another one about Ric Redden! Excerpt: "Horses are very durable, and they'll lie through their teeth about how they're feeling," Redden said. "Do not depend on the horse to tell you how healthy the laminae are. Depend on your venogram."

Feeding Laminitic Horses The Horse 5/1/07

Changing Carbohydrate Evaluations in Animal Diets The Horse 4/15/07

Breeding a Laminitic Mare? The Horse 2/1/07

AHF knocks on doors in Washington Animal Health Foundation 11/06

Another Piece of the Laminitis Puzzle The Horse 11/26/06

Good Foot Gone Bad The Horse 9/1/06


Can Laminitis be Inherited? The Horse 10/1/03

Related studies

Equine Metabolic Syndrome (EMS)

E M S By John Stewart MA VET MB MRVCS

Equine Metabolic Syndrome By Kentucky Equine Research (PDF file)


Equine Metabolic Syndrome a Focus of Research The Horse 8/25/09

Table Topic: Cushing's or Metabolic Syndrome? The Horse 4/17/09

No Sugarcoating: Diagnosing and Managing the Insulin-Resistant Horse The Horse 10/19/08

Equine Metabolic Syndrome Versus Cushing's Syndrome The Horse 2/19/07 by Lydia Gray, DVM, MA

Metformin a Therapy in Progress for Equine Insulin Resistance The Horse 5/25/09

A Closer Look at Insulin The Horse 4/21/05

Minnesota Veterinary Medical Association

New Feeding product from Purina Mills: WellSolve L/S (Low Starch) Benefits: Low starch and sugars, no grains or molasses, digestable/fermentable fibers as an alternative energy source, added antioxidants, veterinarian researched.

Some of the conditions affecting special needs horses include: Insulin resistance and/or Equine Metabolic Syndrome, Laminitis, Cushing's syndrome

Feed is based on beet pulp, alfalfa and ground soy hulls. It also consists of vitamins A, D and E, Biotin, Soy bean oil, ground Flaxseed, Lysine, Threonine, Methionine, minerals; Copper and Zinc

Target IR A supplement that targets the special needs of insulin resistant horses but is also appropriate for any horse on a predominately hay diet. Designed to match the most commonly encountered mineral problems and other deficiencies in grass

Soaking Hay to reduce carbohydrates?

Excerpt from Revised Understanding Equine Nutrition: Energy and Carbs The Horse 6/4/08

Preventing Equine Laminitis and Hyperkalemic Periodic Paralysis (PDF file) by Sloane Lipkin, Jonathan Rose, and Margaret Taylor Governor’s School for Agriculture, Virginia Tech, VA

Cutting Down on Carbs (For Your Horse) Study by Kathryn Watts, BS, director of research for Rocky Mountain Research and Consulting

Take Control of Laminitis in Your Horse by Eleanor Kellon, VMD

Danger in Your Horse's Grass: Fructan

With Horse Hay, Wetter Can Be Better My by Eleanor Kellon, VMD

White Line Disease

White line disease (WLD) is a term used to describe a keratolytic process on the solar surface of the hoof, which is characterized by a separation of the inner zone of the hoof wall (Redden, 1991). The separation occurs in the non-pigmented horn at the junction between the stratum medium and the stratum lamellatum. This separation is invaded by opportunistic bacteria/fungi at the toe, quarter and/or heel leading to infection, which progresses to varying heights and configurations toward the coronet. The disease process occurs secondary to a primary hoof problem such as chronic laminitis, abnormal hoof conformation, hoof imbalance or any other condition that causes a hoof wall separation. The disease has been termed seedy toe, yeast infection, Candida and onychomycosis.

White Line Disease - An Update by Stephen E. O'Grady, DVM, MRCVS




a) Typical signs of WLD

b) Resected hoof (carv out all affected tissue to let hoof air)

c) 3 weeks after resection, hoof dried out

Laminitis Treatment Centers

Premier Equine Center, CA Healing, rehabilitation and conditioning.

Orthopeadic Research Center, Colorado State University, CO

Rocky Mountain Equine Podiatry Center, CO

International Equine Podiatry Center, KY

Rood & Riddle Equine Hospital, Podiatry Center, KY

Louisiana State University, LA

Equine Studies at the University of Maryland, MD

Davie County Large Animal Hospital, NC

Ohio State University, OH

Equine Specialty Hospital, OH

Willamette Valley Equine, OR

Penn Veterinary Medicine, University of Pennsylvania, PA

The Podiatry Center at Reata Equine Hospital, TX Opened the Podiatry Center in April of 2008: Texas Equine Hospital Opening Podiatry Center Some success stories of severe laminitis!!

Northern Virginia Equine - Ocala Equine Podiatry, VA Headed by Dr Stephen E. O'Grady, DVM, MRCVS

Serenity Equine, VA

Valley Equine Associates, WV

Symposiums and Seminars

Bluegrass Laminitis Symposium

Laminitis conference - Palm Beach, Nov, 2007

How can one contribute to Laminitis research?

You can help support Penn's effort: Fight Laminitis

Laminitis Research Gets a Boost Bloodhorse 1/31/08 Pfizer Animal Health and the National Thoroughbred Racing Association have joined forces to help fund laminitis research through the NTRA Charities - Barbaro Memorial Fund.