Sunflower cake in the diet of Quarter Horses in activity

The increased availability of sunflower cake, a by-product of oilseed extraction for biodiesel production, prompted us to test the scope of its utilization in the diet of Quarter Horses employed in equestrian shows. We substituted 600 and 1200 g of feed with 300 and 600 g of sunflower cake, respectively, so as to obtain isoproteic and isoenergetic diets. Digestibility evaluation by the AIA method evidenced generally improved nutrient utilization with the lower cake diet (300 g sunflower). The higher cake diet was associated with a reduction in organic matter, protein and ether extract digestibility coefficients. In particular, the trend of the protein coefficients (88.5 - 91.5 - 87.7 for control, 300 and 600 g sunflower cake, respectively) was confirmed by higher plasma urea levels.