Effect of bioactive proteins on gait kinematics and systemic inflammatory markers in mature horses

Abstract

Twenty-seven mature Quarter horses were used in a randomized design to determine the effects of bioactive protein supplementation on gait kinematics and systemic inflammatory markers in a 34-d trial. Treatments consisted of oral doses of 230 g/d of pelleted supplements containing 0 g (CON; n=9), 40 g of bioactive protein (40BP; n=9; LIFELINE®, APC, LLC, Ankeny, IA), and 80 g of bioactive protein (80BP; n=9) daily. Horses were fed a commercial concentrate at 0.5% BW (as-fed) and received ad libitum coastal bermudagrass (Cynodon dactylon) hay daily. On d 33, horses consistent in exercise (CON, n=6; 40BP, n=8; 80BP, n=7) participated in a trailering and riding challenge. Kinematic gait analysis was performed on d 0 for use as a covariate, and on d 14, 28, and 34 to allow for determination of potential time and dosage effects. Video footage was collected and analyzed using gait analysis software (EquineTec, Monroe, GA) for determination of stride length (SL) and range of motion (ROM). Blood was collected via jugular venipuncture on d 0, 14, 28, and 34 for determination of systemic expression of TNF-α and IL-1β. Data were analyzed using PROC MIXED of SAS. A trend towards treatment × time interaction was observed in ROM of the knee at the walk (P = 0.10), due to the increasing ROM for 40BP and 80BP as time increased and decreasing ROM for CON. A treatment × time interaction was observed (P < 0.01) for hock ROM at a walk resulting from CON and 80BP decreasing from d 14 to d 28 with 40BP increasing, while from d 28 to 34 ROM at a walk decreased for 40BP and increased for 80BP. The main effect of treatment on hock ROM at the walk was quadratic (P < 0.01) and characterized by higher ROM values for 40BP compared to CON or 80BP. Dietary treatment lengthened (P = 0.04) SL of the hind limb at the walk for 40BP and 80BP compared to CON on both d 14 and d 28. A significant treatment × time interaction was observed in expression of IL-1β (P < 0.01) and can be explained by lower concentrations of IL-1β for 80BP on d 34 compared to the other treatments, with 40BP being intermediate and CON being the highest. Increased articular ROM with decreased expression of IL-1β may indicate potential anti-inflammatory effects of 80 g/d of bioactive proteins.

Effects of Crude Rice Bran Oil and a Flaxseed Oil Blend in Young Horses Engaged in a Training Program

“…Interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays an important role in mediating inflammatory responses, and production is often stimulated by strenuous exercise [ 45 ]. In the current study, increases in post-exercise IL-1β concentrations after 30 d are similar to those seen in a study conducted by Fikes et al [ 46 ], where IL-1β showed no changes in the unstimulated state but increased after a strenuous bout of exercise. These findings and those of the current study disagree with studies where conditioning decreased the post-exercise inflammatory response [ 10 ]; however, horses in the current study were not conditioned to perform the intense exercise of the IET.…”