Laminitis

EMS is also referred to as Insulin Resistance (IR) and Hyperinsulinemia.  The condition is often triggered by chronic obesity.  Overfeeding of Non-Structural Carbohydrates (NSC), simple sugars and fructans result in increased uptake of glucose by muscles and adipose tissues.  If this happens in chronic levels, these excess sugars will exceed the fat tissues ability to use and store glucose.  This will result in the muscle and adipose (fat) tissues to improperly respond to insulin.  Hyperinsulinemia will result (the body reacts to compensate for the reduced insulin sensitivity and increase its insulin levels even more). Theory suggests high insulin levels alter blood flow and endothelial cell function causing vasoconstriction to the blood vessels and ultimately to the laminae (in the feet).  High insulin may alter the colonic bacteria increase endotoxins causing inflammatory.

See http://www.durangoequine.com/articles/equine-metabolic-syndrome/

How do I know if my horse has laminitis?

Source:  http://www.debenvalleyvet.co.uk/Event.aspx?informationid=5

·         Shifting weight from foot to foot, often quite slowly and subtly.

·         Wanting to walk on the soft, avoiding gravel etc.  May not want to walk or trot.

·         Warm/hot feet.

·         Pronounced digital pulses – your vet can show you where to feel for these.

Signs of distress may be fast breathing, sweating and laying down more than normal.  Noticed perhaps first is the leaning back ‘toe-relieving’ laminitic stance.

Laminitis can develop for a number of reasons, and is currently a hot area of research. However the single most common cause is:

·         Too many calories!

Other predisposing factors and triggers include:

·         Insulin resistance (especially fat ponies)

·         Cushing’s Syndrome

·         Poor shoeing, especially with too much fast work on hard ground / roads (also known as ‘road founder’).

·         Carbohydrate overload/gorging grain

·         Toxaemia or other disease (e.g. liver)

·         Large doses of steroids, or stress

·         Reduction in workload, but not feed volume

 It is now strongly suspected that if a pregnant mare has poorly balanced nutrition – causing obesity - or a lack of vital vitamins and minerals her foal will be predisposed to insulin resistance and be at higher risk of developing laminitis for its whole life.

Management and feeding:

 Severely restricting the volume of food a horse can eat is not ideal because horses are naturally trickle feeders. Long periods without food can result in gastric ulcers.

High risk grazing:

·         Lush grass

·         Hay aftermath

·         Long, dead-looking old grass

·          Frozen grass (Frost affected)

Feeding tips:

Limit the amount of grazing available by increasing the number of horses, reducing the size of the field or using a grazing muzzle.  Mow fields in the summer if they are not used for grazing or hay to prevent them going to seed.  Turn out onto an area which is small enough to be kept grazed short. Suitable grass looks ½ mud and ½ grass.

Don’t be fooled into thinking there’s no grass – usually there’s only no grass because the horse is eating it as fast as it can grow!  If you are mowing your lawn then the grass is growing – if the field looks bare but you are mowing your lawn twice a week then the horses are eating a lot of grass!

Make sure the diet is balanced for vitamins and minerals, especially whilst feeding lots of low calorie fibre, make available “himalayan rock salt, feed a quality pre & pro-biotic (to re-establish gut flora) and feed a toxin binder”. (http://www.hoofnz.org.nz/html/laminitis.html)

Exercise helps reduce insulin resistance, try to ensure your horse gets a minimum of 30 minutes active walking every day.”

Image by Deben Valley Equine Veterinary Clinic

See: http://www.debenvalleyvet.co.uk/Event.aspx?informationid-5

Source: http://www.thelaminitissite.org/articles/equine-metabolic-syndrome-and-insulin-dysregulation

“A common suggestion is to feed a horse 1.5% of its ideal or current bodyweight (based on soaked hay with added minerals).  Do not reduce to less than 1.2% of the horse’s bodyweight.  Severe calorie restriction can worsen insulin resistance.”

Source: http://www.safergrass.org/pdf/sugar_in_hay.pdf

“Soak hay for at least 60 minutes in cold water, or 30 minutes in hot water, drain and feed before mould has a chance to grow. Use fresh water every time, as sugar will build in the water.”

Source: http://www.barehoofcare.com/AB%20articles/Laminitis%20Recovery.pdf

“Whilst ‘bute’ plays a very important role in the early stages of a laminitic episode, it is really only needed for a matter of days, not weeks and definitely not months. Nutritional supplementation is vital to support the body’s efforts at recovery.

A combination of supplements useful during the healing process include concentrating on the ulcerated stomach and damaged digestive system and then liver cleansing.

Facilitate healing through correct trimming. It’s vitally important to remove all weight from the ‘broken’ laminae. That is the only way it is able to begin healing at the coronet. See pictures A, B & C.

Rehab includes soaking in concentrated salt water, cleaning and wrapping in bandages or baby nappies to prevent infection.

A return to soundness comes routinely at three to four months, when the new lamellar attachment reaches ground level at the heels.”

Source: http://naturalhorseworld.com/newsite/laminitis-recovery/

Food Allowed:

“Free choice average quality grass hay plus oaten chaff with quality mineral and vitamin supplements and a small amount of pellets (Hygain Ice recommended) and a few vegetables for variety.

Once the hooves have regained a sound shape, a small amount of grass is allowed daily (1 hour of grazing with a muzzle on
Treatment Summary:
  

·         A natural trim every week for 8 weeks, then every fortnight for the next 6 weeks & now every 3 weeks.

·          Initial bandaging of the front hoof wounds to keep honey in and dirt out until the wounds were healed (3 months).

·         Painkillers to keep spirits up and encourage some movement (gradually phased out after 4 weeks).

·          Confinement away from grass in a large stock yard on soft footing (sawdust & straw then some pea sized gravel was added in wet areas).”

 

Visible Pedal Bone Penetration               

  

Visible blood in the white line   

Bath frequently and bandage  to protect from further infection

Source: http://holistichorse.com/health-care/feeding-the-horse-with-winter-laminitis/

Chinese Food Therapy

Omega-3 fatty acids are very important in the treatment of laminitis. Hemp seed moistens the intestines to promote bowel movement, and is sweet and neutral. Flax and Chia seeds have similar effects. All of these have anti-inflammatory properties and help correct insulin and glucose usage.

Minerals

One of the most important aspects of any nutritional program for horses is the use of free choice minerals and salt fed separately. Many laminitis horses will eat large quantities of minerals for extended periods. Sulfur may be an important nutrient for these horses and can be fed free choice or in an MSM supplement.

Other Nutrients:

Antioxidants:  Vitamin C is an excellent antioxidant and supports the immune system healing. Coenzyme Q10 seems to one of the best antioxidants for use in horses, especially in cases of laminitis.

Chromium:

Chromium  has been found to be beneficial in diabetic experimental animals and also in conditions resulting from insulin sensitivity and defects in glucose transportation (Liu et al., 2010)

Source:https://dspace.library.colostate.edu/bitstream/handle/10217/65346/OtabachianSmith_colostate_0053N_11108.pdf?sequence=1&isAllowed=y

Electrolyte Loss & Replacement Strategies

Did you know a horse not in work loses up to 10 litres a day in sweat! That means losses of 10 grams of Sodium, 10 grams of Chloride, 25 grams of Potassium and 10 grams of Magnesium!

A horse in mid range work sweats by comparison 27-43 litres a day.  That means losses of up to 43 grams of Sodium, 71 grams of Chloride, 43 grams of Potassium and 13 grams of Magnesium.

Tying up is a common problems in performance horses. Research in England suggests tying up is related to electrolyte imbalances.

So how do you replace these significant electrolyte losses?  A portion of sodium and chloride can be obtained by providing a salt lick block.  Potassium can be picked up in forage, typically hay provides 10-20 grams per kg.  German research revealed horses fed adequate forage maintained better water and potassium balances during exercise than horses fed a high concentrate diet (Grain).

http://www.minrosa.com.au/pages/

Magnesium however is not readily available in sufficient quantities to replenish a horses needs.  Magnesium must be fed in conjunction with Calcium (close to 3:1 Calcium: Magnesium) in conjunction with Boron to be adequately supplied to and utilised by the small intestine.

Why is my Horse Itchy and how to manage successfully

Finding the cause to an itch is paramount to finding the right solution, whether it be eradication of the cause or a long term successful management of the diagnosed condition.

Horses confined to paddocks or stables, are often in close proximity to other horses creating a breeding ground for diseases and parasites that affect the skin.

Sarcoptes is perhaps the best known cause of itch and hair loss in the mane and tail of horses.  The microscopic female mite when impregnated tunnels into the skin and deposits eggs in the burrow. The larvae hatch in 3 to 10 days, move about on the skin as they mature into adult mites.  Adult mites live three to four weeks in the host’s skin.

The action of the mites moving within the skin and on the surface itself produces an intense itch that may resemble symptoms of QLD Itch.  Their excreted faeces resemble dandruff or scurf and are often mistaken as just that.  Thinning of the hair occurs as they damage the hair follicles causing reduced hair growth and hair fallout.

Some skin disorders do not cause itching, but secondary infections such as bacterial or yeast infections cause the horse to itch and subsequently hair loss.  It is possible the time the itch occurs the initial skin disorder is long gone.  Your vet will perform a skin scraping to identify the cause of the itch, likely parasites are considered as the first cause of an itch.

Treating mites successfully requires application of a mite killing insecticide to be applied externally every 4^th day for at least three weeks to ensure the breeding cycle is broken.  As the insecticides work only at the skin surface, each lot of hatchlings needs to be treated, hence the ongoing treatment method to ensure a completely successful eradication. Treating rugs and companion horses is also best practise. Seek veterinary assistance to select a suitable insecticide.

Rain scald can be attributed to Dermatophilus Congolensis.  This organism likes to infect traumatized skin, particularly in the presence of high moisture.  Young horses with poorly developed immune systems are at a higher risk of getting rain scald.  Skin trauma can be initiated by abrasions, insect bites or frequent rain exposure that softens the skin, particularly along the horse’s topline.

Once dermatophilus congolenis takes hold most likely secondary bacterial infections occur such as staphylococcus (staph) and or streptococcus (strep).  Hence it is of paramount importance to treat the rain scald immediately before any secondary infections break out. ^A

The best treatment is to wash the horse with antimicrobial and antibacterial shampoos once a day for a week.  Allow the shampoo 10 minutes to sit before rinsing thoroughly.  Condition and dry off.  In severe cases prescription antibiotics will need to be prescribed by a qualified vet.

QLD Itch is an allergic reaction to the saliva of biting midge (biting insects that colonized near a water source and feast at dusk and dawn on nearby stock).  Getting an accurate diagnosis from skin scraping or veterinary assessment is the first step to managing this condition correctly. 

Often times sarcoptes mites are the culprit behind the itch, not the midge or biting flies.  Noticeable symptoms that extend through the cooler months and exhibit dandruff symptoms are an indication the itch is mite related.  Sometimes the horse is dealing with both mites and QLD Itch in warmer climates.

Prevention is the likely successful approach.  Warding off the biting insects by rugging from dusk to dawn and applying a water resistant insect repellent to the exposed areas will greatly reduce the rate of biting flies. 

Secondly try to minimise the infections that occur to the broken skin from rubbing such as bacterial and yeast infections.  At this stage people start to recognise their horse has QLD Itch. 

Washing the horse with a medicated shampoo each week, keeping rugs clean and the horse dry will minimise the skin related infections.  Humidity also increases skin related infections, so do not allow the horse to sweat underneath constant rugging in warm weather.

Science behind the itching reaction

A mast cell is part of the immune system and contains many granules rich in histamine and heparin.  Although best known for their role in allergy and anaphylaxis, mast cells play important protective roles as well being intimately involved in wound healing including angiogenesis and defence against pathogens.

Histamine as part of the immune response to foreign pathogens, produced by both basophils and mast cells.  Histamine increases the permeability of the capillaries to white blood cells and some proteins, to allow them to engage pathogens in the infected tissue. 

Heparin has been proposed to defend at such sites against invading bacteria.

To signal the correct response cytokines (small proteins) are released by cells to affect the behaviours of other cells.

The problem with allergic reaction occurs when incorrect signalling occurs at this cytokine level.  Loosely put they can signal a Type 1 or Type 2 response to favour either a cellular immune response or an antibody response.^B  Type2 (T_h2 ) over activation against auto antigen will cause Type1 IgE-mediated allergy and hypersensitivity.

As a result of a faulty allergic response the horse begins to rub from an ‘over reactive itch response’, next pathogenesis occurs – the skin enters a diseased state and becomes microbial infected, inflamed or has tissue breakdown.

The gastrointestinal system plays a central role in the immune system.^C  New scientific approaches to managing an itchy horse include feeding supplements that may work from the gut to down regulate the over reactive immune response.  Ask at your local feed store for a supplement that works from the inside to benefit holistically.

Veterinarian approaches to managing the symptoms of classic QLD Itch include regular bacterial skin washes, applying effective insect repellents and injections with cortisone are administered in extreme cases.

External solutions that can be applied to skin are popular methods to manage the new infections occurring on the skin surface.  Caution should be exercised using any Iodine based preparations as these may lead to hypothyroidism, result in hair loss and un-wellness with long term use.

Soothing oil preparations with insect repelling properties are popular; however caution should be exercised not to apply in the heat of the day.   It is well know that healing skin must breathe to heal successfully, so resting skin for a few days between applications is best practise.

Pin Worms

The adult worm lives in the rectum and lays its eggs on the surrounding skin externally.  Pin worms cause severe irritation and sometimes horses rub so badly so as to rub the tail head raw leading to secondary infections and hair loss.

To treat successfully some helpful tips include, using a pyrantel based wormer repeating every 6-8 weeks.  Clean the horse’s rectum first thing in the morning to remove eggs.    Apply Vaseline to surrounding skin to help reduce the number of eggs that stick to the skin.  Keep up treatment with wormer for minimum of 12 months as the immature stages of the worm are less sensitive to wormers so may survive post worming.

Neck Threadworms

Referred to as neck worms the adult Onchocerca Cervicalis worms live in the large nuchal ligament that runs from the poll to the withers.  The reproduction process lands the highly irritating microfilaria (larval) around the face, shoulders, chest and abdomen on the horse where biting flies come to feed.  The culicoides fly serves as the carrier, reinfecting and spreading the larvae. The adult Onchocerca Cervicalis worms do not usually cause discomfort to the horse and will reside within the neck for around 10 years meanwhile laying thousands of eggs each year. 

Often inflammation occurs on the underbelly, ending in self trauma to the skin and chest as the horse rubs intensely to relieve the itch.  Another tell tale sign includes a bullseye of hair loss and inflammation on the horse’s forehead.  Most horses exhibit dermatitis, crustiness, hair loss, itching, swelling and self trauma, often mistaken for QLD Itch.

Usually younger horses even though infected may not have symptoms until the age of 5 or more, hence the sudden onset of itch to a horse previously not itchy.

Treatment of the microflilaria can be achieved with regular doses of ivermectin or moxidectin (some recommend weekly or fortnightly) until symptoms subside.  A horse that has neck worms will demonstrate increased itching for 48-72 hours post worming.  The total onchererca life cycle lasts from 4 to 5 months, so consistent treatment is a priority. 

Excellent additional reading can be found at http://thehorsesback.com/neck-threadworms/.

A.       http://www.equusite.com/articles/health/healthRainRot.shtml

B.       http://cid.oxfordjournals.org/content/32/1/76.short

C.       http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2515351/