275. Dogs Fed Faba Bean Protein and Starch Concentrate, or Flour Based Diets had Similar Body Composition, Serum Biochemistry, Plasma Amino Acids and Cardiac Function After 26 Weeks.

Abstract

Faba bean (Vicia faba L.) is a sustainable, high-protein pulse crop; however, use in canine diets has been limited due to lack of approval by regulatory or authoritative agencies, the presence of anti-nutritional factors (vicine and covicine [V/C]), and relatively low concentrations of the sulfur-containing amino acids. This study incorporated flour, starch, and protein concentrate derived from a low V/C faba bean cultivar (Fabelle) into adult dog diets. The primary objective of this study was to evaluate the long-term safety and nutritional adequacy of dehulled Fabelle faba bean derived ingredients in adult dogs fed at maintenance and compare those to a corn-based diet over a 26-week feeding period. Thirty-six healthy privately-owned adult Siberian Huskies (1-14 years) were randomly assigned to one of three diets (n = 12/group): a corn-based control (CTL; crude protein (CP):37.5%), dehulled faba bean flour (FABA1; 41.5% inclusion; CP:36.0%), or dehulled faba bean starch and protein concentrate (FABA2; 36% and 8% inclusion; CP:40.0%). Following a 4-week CTL wash-in, dogs were randomized to treatments balanced for age, sex, body weight (BW) and echocardiographic (ECHO) ejection fraction and then fed the experimental diets for 26 weeks. Health and safety were assessed through BW, feed intake (FI), body composition by dual-energy X-ray absorptiometry (DEXA), serum biochemistry and plasma analysis by ultra performance liquid chromatography of thiols (cysteine, homocysteine, and cysteinylglycine) with ongoing analysis of remaining amino acids. Cardiac health was assessed using plasma high-sensitivity cardiac troponin I (hs-cTnI), and ECHO. BW and FI were recorded weekly, with DEXA and ECHO at weeks -2 and 24 and blood samples collected at baseline and weeks 1, 3, 7, 15, and 25. Data was analyzed using PROC GLIMMIX in SAS. Overall, inclusion of faba bean ingredients resulted in no adverse biochemistry, cardiac, or body composition outcomes. Both BW and FI were maintained throughout the study, but all groups had greater BW on weeks 19 and 16 (P < 0.01). Although several serum biochemistry parameters were affected by week, diet, or the interaction, all values remained within reference ranges. Analyzed homocysteine concentrations tended to be greater in CTL compared to FABA2 and both were similar to FABA1 (P = 0.056). ECHO and DEXA measurements were similar among diets (P ≥ 0.360), with a trend observed for left ventricular length being greater in FABA2 compared to CTL (P = 0.098). hs-cTnI had no treatment effect (P = 0.801) with all treatment group averages remaining below the clinical threshold (<20-49.9 ng/L), indicating preserved myocardial integrity. Collectively, these results suggest that faba bean ingredients are well tolerated and support the safe use and commercialization of Fabelle faba bean derived ingredients in adult dog diets, as the 26-week feeding period satisfies Association of American Feed Control Officials (AAFCO) criteria for adult maintenance claims.