Lamellar perfusion and energy metabolism in a preferential weight bearing model

Background: Supporting limb laminitis (SLL) is suspected to be caused by lamellar ischaemia as a consequence of increased mechanical load.Objectives: Examine the effects of prolonged preferential weight bearing (PWB) on lamellar perfusion and metabolism.Study design:\ua0In vivo\ua0experiment.Methods: Microdialysis probes were inserted in the lamellar and sublamellar dermis of one forelimb in 13 Standardbred horses. In 6 horses, a platform shoe (contralateral forelimb) was used to induce increased load on the microdialysis‐instrumented forelimb (PWB). The remaining 7 horses were controls (CON). All horses were housed in stocks with limb weight distribution logged continuously for 92 h. Microdialysate was collected and analysed every 4 h for glucose, lactate, pyruvate and lactate to pyruvate ratio (L:P). Microdialysis urea clearance was used to estimate lamellar perfusion. Data were analysed using a mixed‐effects linear regression model.Results: Median [IQR] load on the microdialysis‐instrumented limb was equivalent to 38.7% bwt. [37.3‐40.3] in PWB and 27.3% bwt. [26.6‐28] in CON. Limb offloading frequency increased in CON (