Bob Childs - ESA/AHA/PHCP Certified Hoof Specialist


Metabolic Syndrome in Horses
By admin | | EMSLaminitis |

Article by: Philip J. Johnson, BVSc, MS, MRCVS, DACVIM

Affected horses tend to be aged between 6-to-20 years and there does not appear to be a sex predilection. The problem is reported more commonly in some pony breeds, domesticated Spanish mustangs, Peruvian Pasos, Paso Finos, European Warmbloods, American Saddlebreds, and Morgan horses. Affected horses are commonly obese and develop excessive adiposity at specific locations, especially in the crest of the neck, at the shoulders, above the gluteal muscles, and in the sheath (geldings). Female horses are notoriously difficult to breed and exhibit abnormal ovarian cycling behavior. Horse owners refer to many of these horses as "easy keepers" and vigorously contend that all efforts to reduce the horse's obesity by dietary restriction are futile. Ample intra-abdominal (omental) adiposity is evident during ultrasonographic examination of the abdomen or at necropsy of affected horses.

Many of these horses are presented to veterinarians for diagnosis of lameness attributable to laminitis. There is a very strong association between the development of obesity, metabolic syndrome and the risk for developing laminitis. Commonly, at initial veterinary examination, there already exists both physical and radiographic evidence for long-standing laminitis in these horses although reputable and credible owners and managers report that there have been no prior signs of laminitis or any obvious explanation. Metabolic syndrome is often recognized incidentally when horses are presented for other reasons, such as routine health care or other medical problems. In these horses, visible changes in the hoof that are commonly attributable to laminitis (including prominent growth lines, palmar divergence of growth lines, and a convex sole) may be evident in the absence of laminitic pain or any history of laminitis or lameness. There are minimal hematological changes in horses affected with metabolic syndrome (unless laminitic pain is prominent). Abnormal results of routine serum biochemical profiling might include a slight-to-moderate elevation in the glucose and triglyceride concentrations.

Laminitis and Obesity
By | | Laminitis |

Interesting comments on laminitis and obesity by Donald M. Walsh, DVM

"Based on my experience observing laminitic horses over the past 36 years in veterinary practice, I believe that obesity leads to the development of weakened laminae and other supporting structures of the foot and to changes in the growth pattern of the feet. 2 Radiographs reveal that the appearance of the laminae begins to change in horses that are becoming obese, even before any signs of lameness from laminitis are observed.

Perhaps, when a horse becomes obese, there is a messenger substance that promotes or allows for the skin's basement membrane to stretch so the skin can "enlarge itself" in order to accommodate for the increased layer of fat under the skin. If this is so, perhaps this same messenger substance is also recognized by the epithelial laminar basement membrane in the foot, which would cause the basement membrane to stretch, which could result in the weakening of the laminae of the foot in the obese horse. These weakened feet are much more susceptible to grass laminitis and other predisposing insults known to cause laminitis.

Obese horses need a major change in lifestyle in order to become healthy. Accomplishing this can be a challenging task for the owner because weight reduction in these horses requires a low caloric diet together with a considerable amount of exercise. Many of the horses experiencing laminitis are so sore-footed that much exercise is not possible. Many live lives of constant pain associated with ongoing bouts of laminitis, which finally results in so much damage to the feet that recovery is impossible. These (heavy-type) horses are the most common group associated with the ingestion of grass as a cause of laminitis."