The potential for participation of the arginine-nitric oxide system in the aetiology of acute equine laminitis has been assessed. Nitric oxide (NO), produced by the action of NO synthase (NOS) on its substrate l-arginine, relaxes vascular smooth muscle to cause vasodilation. An attenuated normal vasodilatory tone may characterise the pathogenesis of acute equine laminitis. An intravenous infusi...

A dairy cow’s environment may influence the onset of laminitis and associated claw horn lesions by exacerbating changes in the hoof triggered by events at parturition, onset of subacute ruminal acidosis, or claw horn growth and wear and ground reaction forces on different walking surfaces. Environmental risk factors for laminitis and associated claw horn lesions include feed bunk space and desi...

Laminitis has been described in many species, but is most common in the equine and bovine. Although bovine laminitis is most common in lactating dairy cows, it has been reported in all ages and sexes. Laminitis is an inflammation of the laminar corium of the hoof wall, and also includes the sole corium in the bovine definition. In general, the term laminitis is used to describe a systemic disea...

Introduction Laminitis is an expensive and emotionally draining disease for the equine industry, whose pathophysiology remains unclear. The disease carries a higher morbidity and mortality rate compared to other causes of equine lameness. The appearance of chronic laminitis with magnetic resonance imaging (MRI) in cadavers has been described, but the usefulness of MRI in evaluating laminitis in...

Pasture-induced laminitis in the horse is associated with the overconsumption of fermentable carbohydrate, in the form of simple sugars, fructans, or starch. The fermentation of carbohydrate in the cecum and large intestine results in the production of lactic acid and other toxins or "laminitis trigger factors." Vasoactive amines have been suggested as possible initiating factors. The aim of th...

Over the past 20 yr, extensive research efforts as well as clinical experience has greatly increased our knowledge base of equine laminitis. Our present understanding of the disease is that there is failure of the lamellar attachment between the distal phalanx and hoof wall. This, in turn, initiates a sequence of events ranging from no permanent structural damage to loss of the hoof capsule. Af...

Research into the structure and function of the hoof wall has proven fundamental to the understanding of how important diseases such as laminitis develop. This article reviews current information on the equine hoof wall and its internal lamellar layer (with notes on the developmental mechanism of laminitis) in the hope that a more unified approach to the rational management of the hoof wall, by...

A method for culturing explants of lamellar hoof was developed to investigate the process of lamellar separation that occurs in laminitis. Explants, consisting of hoof wall, dermal and epidermal lamellae and the adjacent sub-lamellar connective tissue remained intact when cultured in tissue culture medium for 2 days. However, when cultured in the presence of the matrix metalloproteinase (MMP) a...

Laminitis, a highly debilitating disease of the foot in ungulates, is characterized by pathological changes of the complex lamellar structures that maintain the appendicular skeleton within the hoof. Laminitis is a multifactorial disease that involves perturbation of the vascular, hematological, and inflammatory homeostasis of the foot. Interestingly, the pathogenesis of the disease resembles w...