In this, I will be focusing on the laminitis in horses, with laminitis in cattle not necessarily being confined to just the laminar region. [4]
Causes & Transmission
In laminitis blood flow to the laminae is cut off, causing inflammation and swelling within the hoof and severe pain. This starves the laminae of oxygen and nutrients, causing them to die.
Laminitis can be caused by various metabolic or physical reasons, and is particularly known to be linked to diet. Obesity both adds to the strain placed on the laminae by increasing the weight they have to support, and through hormonal activities of the fat cells within fatty tissue. [5] Increased amounts of glucose also increase the amount of insulin produced, with high levels of insulin in the blood being linked to, if not directly causing laminitis. [6] Laminitis is more commonly seen in the front feet.
Risk factors include:
Excessive intake of sugar and starch (soluble carbohydrates) - This overloads the digestive system, meaning some goes undigested into the hindgut. Bacteria then breaks this down, increasing the acidity in the hindgut and killing the bacteria which digests fibre. Toxins are released as these die, which then pass through the gut wall to the bloodstream. These toxins produce a response thought to disrupt blood flow, causing laminitis.
Obesity - Internal fat is hormonally active, excreting hormones such as cortisol and inflammatory factors that can trigger a change in the hoof.
Severe infection - As toxins are released by bacteria during certain illnesses.
Repeated physical trauma to the feet - A horse worked fast and for a prolonged period of time on a hard surface can affect the laminae, being a common cause for lamintis.
Severe lameness in one limb - This will cause a horse or pony to carry excessive weight on his other limbs, which may lead to laminitis.
Cushing's disease - This is associated with an abnormality in the pituitary gland, at the base of the brain. Laminitis is often a result of this disease.
[7][8][9]
Symptoms & Diagnosis
The horse may be depressed and reluctant to eat (anorectic), showing an unwillingness to walk, stand or rise, instead laying down. The horse may stand in a way so as to relieve weight or pressure from the affected feet; if all are affected, they may shift their weight from one side to another. The horse will appear visibly lame, potentially walking by placing the heel down first rather than toes first or walking with a slow, crouching, short-striding gait. Symptoms may also be similar to colic. The entire hoof may be warm with muscular trembling and tenderness when pressure is applied. In severe cases, the bone may penetrate the sole just in front of the point of the frog.
Diagnosis is often based upon history (for example diet), posture, an increased temperature of the hooves and reluctance to move. Nerve blocks (Which interrupt pain signals in the way the name suggests) of the forelimbs allow the hind feet to be assessed for laminitis.
Treatments
Recovery from laminitis is dependent on factors such as severity of the illness when noticed and how quickly treatment is administered. Changes to diet and management can improve mild cases, especially those brought on by poor nutrition. [10]
Standard shoes should be removed for the first two or three weeks, as these place stress onto the laminae and hoof wall. A softer substance should be used in its stead, for example padded with foam cut to the diameter of the foot, between one and two inches thick. [11]
Treatment should occur as soon as possible, so as to limit suffering caused by pain, provide analgesia (pain relief) and to prevent any lasting damage. X-rays may be taken, to find if rotation of the pedal bone has occurred, while a farrier may correct the position of the pedal bone under veterinary supervision. [12] Comfort should be a priority, as laminitis can be affected by factors such as stress, with a change to diet also being necessary, due to the link between this disease and nutrition.
"Dieting ponies and horses should be given around 1.25 - 1.5 per cent of their body weight in food – this includes any grass and hay intake.
Follow the rule of feeding little and often. This mimics the horse’s natural feeding pattern and will help keep the digestive system working correctly. It will also satisfy the horse’s need to chew and prevents boredom.
Never starve a horse or pony as this can lead to serious health problems such as hyperlipaemia and only feed high fibre, low carbohydrate and low sugar products."
[13]
(For further in depth information into the treatment of laminitis, particularly regarding the specific drugs used and potential surgical procedures performed, dependent on the severity of the illness, the Treatment section provides this information.
http://www.merckmanuals.com/vet/musculoskeletal_system/lameness_in_horses/laminitis_in_horses.html)
References - provided general understanding of the disease; including symptoms, causes and treatments
Laminitis Treatment, Advice and Management
http://www.laminitis-advice.co.uk/
- Meaning of laminitis [1]
Equine Laminitis - How to prevent it, spot the symptoms and treat for laminitis
http://www.topspec.com/laminitis-in-horses/
- Movement of pedal bone; progression of laminitis [2]
- Laminitis and obesity [5]
- High levels of insulin linked to laminitis [6]
- Causes [7]
- Treatment regarding changes of nutrition [10]
Laminitis a serious, crippling disease of horses, ponies and donkeys
http://www.animedvets.co.uk/laminitis.htm
- Founder, the sinking of the horse's foot [3]
Laminitis in Cattle: Lameness in Cattle: Merck Veterinary Manual
http://www.merckmanuals.com/vet/musculoskeletal_system/lameness_in_cattle/laminitis_in_cattle.html
- Term laminitis misleading in cattle, as not always within laminar region [4]
Blue Cross - Laminitis
http://www.bluecross.org.uk/2146-2832/laminitis.html
- Causes [8]
- Observing rotation and subsequent correction of the pedal bone [12]
- Quote, excerpt from prevention of laminitis nutritional guideline [13]
Laminitis in Horses: Lameness in Horses: Merck Veterinary Manual
http://www.merckmanuals.com/vet/musculoskeletal_system/lameness_in_horses/laminitis_in_horses.html
- Causes [9]
- Replacement of shoes, the material used and when [11]
Images
http://www.equipodiatry.com/images/realign_p3/fig4.jpg
https://www.vetstream.com/watkinsandtasker/html/images/24_266721.jpg
http://www.clccharter.org/maya1/End%20of%20year%20project/severity.png
http://thedailybongo.com/pics/EquineFetlock.jpg
Charlotte O'Connor