The efficacy of intravenous heparin administration (100UI/kg/8h, from 24 to 48h after carbohydrate administration) in the control of carbohydrate overload-induced equine laminitis (17.6g of corn starch/kg live weight) was evaluated. Fifteen horses were allocated into three experimental groups: GI (control group), GII (laminitis group), and GIII (laminitis+heparin group). These animals were submitted to physical and laboratorial examination during 48h. After that time, they were euthanized with intravenous administration of 5ml of acepromazine followed by 1g of thiopental sodium and 1 liter of saturated solution of KCl to obtain hoof tissues samples for histological examination. GII and GIII horses developed laminitis, showing lameness 12 and 24h after carbohydrate administration, respectively, as well increased heart rate and capillary refill time. The histological alterations, similar in GII and GIII, were degenerative lesions, as thinness of epidermal lamina, retraction, flattening and dislocation of the dermal lamina, epidermal vacuolization, and disruption of the epidermal tissues. The occurrence of laminar degeneration was not prevented or attenuated with intravenous heparin administration.
equine; laminitis; carbohydrate; heparin
