227 Apparent and true digestibility of minerals in animal and vegetable ingredient based adult maintenance dog food

Abstract

penetration to meet F o = 8 min at 121°C and 21 psi. The three sampling points for vitamin analysis were 1) batter without vitamins , 2) batter with vitamins, and 3) post retort loaf product. Samples from 1 and 2 were stored in the freezer (-20°C) and from 3 were stored at room temperature. Composite samples were analyzed for proximates (moisture, crude protein, crude fat, ash), pH, and B vitamin (thiamine, riboflavin, niacin, pyr-idoxine, pantothenic acid, biotin, folic acid, cobalamin) concentrations. Results were analyzed using the GLM procedure in SAS (v. 9.4) with means and interactions separated using Fischer LSD method by significant F values and an a of 5%. The proximate composition and pH were similar (P > 0.10) among treatments. Neither container size nor container type had an effect on riboflavin, pyridoxine, or cobalamin concentrations (average 87.0, 179.0, 0.41 mg/kg, respectively). Small containers retained more (P < 0.05) thiamine than medium (3,209 and 2,513 mg/kg), niacin (909 and 861 mg/kg), and folic acid (22 vs 15 mg/kg), while pantothenic acid retention in small containers was lower (P < 0.05) than medium (273 and 324 mg/kg, respectively). The main effect means for container type only influenced thiamine concentration, wherein retention was greater for pouches than for trays with cans intermediate to both (2,540, 2,359, and 2,274 mg/kg). This work suggests that thermal processing of B vitamins can be influenced by container size and type, which likely relate to the controls over the heating and cooling cycle. Minerals are essential in the diet of dogs throughout all life stages. There is a dearth of knowledge with regards to mineral digestibility in canines, and current knowledge focuses on the digestibility of supplemented minerals, not of endogenous mineral bioavailability of ingredients or formulated diets. The objective of this study was to determine the apparent digesti-bility and true digestibility of macro and trace minerals in ca-nines fed either animal or vegetable based adult maintenance diets. We hypothesized that dogs fed the animal ingredient based diet would have higher mineral digestibility as compared to dogs fed the vegetable ingredient based diet. This study was designed as a 4 × 4 replicated Latin square. Eight purpose bred Beagles (2 intact males, 6 spayed females) of similar age (2.12 ± 0.35 years) were pair housed but fed individually based on individual energy requirements. Four diets (animal ingredient based diet, vegetable ingredient based diet, animal ingredient based diet diluted to 50% ad glucose , and vegetable ingredient based diet diluted to 50% with ad -glucose) were fed to dogs with titanium dioxide included in the diet at 0.3% to enable calculation of digestibility. Kennel numbers were randomly assigned to each pair of dogs with all 8 dogs cycling through the 4 trial diets in random order. Each diet was fed for 10 d, and fecal samples were collected from d 6 to 10. Data were analyzed using a mixed model through SAS (version. 9.4, SAS Institute) with treatment, period, and kennel as a fixed effect and dog as the random effect. There was no difference in apparent digestibility of calcium between dogs fed vegetable vs. animal diets; however, dogs fed the vegetable based diet had greater true digestibility of calcium (P = 0.0143) as compared to dogs fed the animal based diet. The apparent and true digestibility phosphorus and iron were greater in dogs fed the vegetable based diets as compared to animal based diets (P < 0.001). There were no differences in apparent or true digestibility of potassium, copper, and zinc between dogs fed the animal and vegetable based diets (P > 0.05). These results suggest that apparent and true digestibil-ity do not result in similar conclusions, and digestibility of endogenous minerals are similar or greater in dogs fed diets that are largely vegetable based. 228 Chemical composition, nutrient digestibility, and true metabolizable energy of differentially processed chicken-based pet food ingredients using the precision-fed cecectomized rooster assay. In addition to the nutrient composition of raw ingredients, processing conditions may greatly affect the quality and di-gestibility of protein-based ingredients used in pet food products. Testing the quality of protein sources undergoing different processing conditions provides important information to pet food producers. Therefore, the objective of this study was to determine the chemical composition, nutrient digest-ibility, and nitrogen-corrected true metabolizable energy (TMEn) of chicken-based ingredients that had undergone different processing conditions using the precision-fed cececto-mized rooster assay. Chicken meal was compared to raw (no processing; frozen), steamed (cooked to 200°F and held for 10 min at 200°F, cooled, and frozen), and retorted (retorted at 250°F for 30 min, cooled, and frozen) chicken ingredients. Chicken meal had higher ash [16.3% of dry matter (DM)] and crude protein (CP; 67.4% of DM) but lower acid-hydrolyzed fat (AHF; 15.7% of DM) and gross energy (GE; 5.09 kcal/g of DM) than raw chicken (5.8% ash; 41.7% CP; 52.4% AHF; 6.98 kcal/g), steamed chicken (6.7% ash; 53.0% CP; 44.8%