Equine Laminitis

1-  Metabolic Laminitis

-   The horses have abnormal control of carbohydrate metabolism and as a result have abnormally high levels of the insulin. This result in two diseases: pituitary pars intermedia dysfunction (PPID; Cushing’s disease) and equine metabolic syndrome (EMS)

-  The abnormal processing of dietary carbohydrates in both of these conditions involves an excessive insulin response to starches (main carbohydrate in grains) or sugars (main carbohydrates in grasses and hay) in horse feed

-  Pituitary pars intermedia dysfunction (PPID; Cushing’s disease): PPID is a disease of ageing, where the control of pituitary gland hormone secretion is lost, leading to excessive secretion from a certain part of the gland (the pars intermedia, as in PPID) leading to hyperadrenocorticism. The clinical signs include:

a- A long hair coat due to delayed shedding.

b-  Sweating.

c-  Loss of muscle mass.

d-  Development of a pot belly and drinking excessively.

N.B

-  Some of the hormones produced from the pituitary also affect carbohydrate metabolism and can predispose to laminitis.

- Many PPID horses/ponies may have been originally fat, so when they lose muscle their    fat often looks strange and lumpy, but PPID is not caused by obesity.

-  Equine metabolic syndrome (EMS )  

 Tend to occur in genetically predisposed breeds and is worsened by obesity. This does not mean that all obese horses or ponies have EMS, but if the horse or pony has EMS then obesity will worsen the carbohydrate metabolism and predispose to laminitis.

2- Sepsis-associated laminitis

              Sepsis-associated laminitis, which occurs in cases of severe systemic inflammation, which associated with serious illness and bacterial endotoxin production. Examples include salmonellosis, colic, bastard Strangles, Potomac Horse Fever, and retained placenta.  

3-     Supporting limb laminitis

             Support limb laminitis (SLL), the least common type of laminitis, occurs in horses suffering a non-weight-bearing lameness. Laminitis develops in the opposite supporting limb due to prolonged excessive weight-bearing.