PSVIII-7 Performance of blood meal as secondary protein sources in extruded dog and cat diets.

Abstract In light of increasing global demand for a diversity of protein sources in pet nutrition, blood meal (BLDM; crude protein: 86%, crude fat: 3.4%, crude fiber: < 0.2%, ash: 2%) was assessed for nutrient digestibility, and palatability in adult cats and dogs and urine pH in cats. The BLDM was included at 0%, 1%, 2.5% and 5% in chicken-based extruded dog diets (35% crude protein, 16.7% crude fat, 4% crude fiber, 7.6% ash) and cat diets (39% crude protein, 17% crude fat, 4.3% crude fiber, 8.1% Ash). The study was approved by the facility’s Institutional Animal Care and Use Committee. A standard 2-bowl palatability test over a 2-day period was executed (n=30 animals each) to determine intake ratios between each diet (e.g., 0% vs. 1% BLDM). Total tract nutrient digestibility was evaluated (n=6 animals per diet) with 5 days of diet acclimation followed by 5 days of total fecal collection. Stool quality was evaluated on a 1 to 5 scale. Palatability data were analyzed using pair t-test. Urine pH was evaluated (n=10 cats per diet) with diets fed for 7 days and urine pH recorded on day 7. To test for mean differences in digestibility and stool quality outcomes between 0%, 1%, 2.5%, and 5% BLDM, we applied the Kruskal-Wallis test. Statistical significance was set at 5% type 1 error rate. Dry matter, protein, fat, and energy digestibility, and stool quality were similar between diets for cats and dogs (P > 0.05). For cats, palatability was not impacted (P > 0.05) with inclusion of BLDM. For dogs, palatability declined (P < 0.05) with inclusion of BLDM (i.e., preference for 0% vs 1, 2.5 and 5% inclusion) preference declined (p < 0.05) at higher levels (e.g., preference for 1% vs 2.5 and 5% inclusion). For cats, a linear increase (p < 0.05) was seen for urine pH with inclusion of blood meal. Decreased palatability could be linked to the high biogenic amine index of the ingredient (14, with > 10 being considered very poor quality). The blood meal was high in iron (3100 ppm). Excessive iron can contribute to oxidation in the diet and for the pet and should be accounted for during formulation. For diets fed herein, iron increased in the diets with increasing blood meal from 235 ppm in 0% BLDM diets to 315 ppm in 10% BLDM diets. Although digestibility was maintained for both species, and palatability maintained in cats, the higher biogenic amine index and poor palatability in dogs indicates that additional development work would be recommended prior to leveraging blood meal in pet foods.