Dog Diets Research Articles

Dry food affects the oxidative/antioxidant profile of dogs.

Including adequate concentrations of antioxidants in dog diets has been recommended to reduce their vulnerability to the action of free radicals and reactive oxygen species (ROS). Oxidative stress in dogs has been associated with a wide range of diseases and disorders, as well as with ageing. There are few reports about the influence of diet on dog's antioxidant profile and oxidative stress. The objective of this study was to evaluate the effect of four types of dry dog food on the oxidative/antioxidant profile of dogs. Six Beagle dog males were used. The study included four experimental diets (dry foods A-D). Each dry food was supplied for 5 weeks to all dogs, for a total of 24 weeks, including an adaptation week between one food and another. For each dry dog food, the total phenolic content (TPC), total antioxidant capacity (TAC) and cytotoxicity were evaluated. Each week, a blood sample was collected to measure ROS and TAC of plasma. A crossover repeated measures design was used. Mixed models were adjusted, and means were compared using the Tukey test. Food A had the highest values for TPC and TAC. Food C had the lowest levels of ROS, whereas food B had the highest TAC in the blood plasma. The dog had a significant influence on the redox state of its blood plasma, even when the same dog was fed the different dry foods. Dry dog food influences the oxidative/antioxidant profile of dog's blood plasma; however, this seems to be unrelated to the antioxidant profile of the food.

High-protein dried distillers grains in dog diets: diet digestibility and palatability, intestinal fermentation products, and fecal microbiota.

This study aimed to evaluate the effects of high-protein dried distillers grains (HPDDG) on palatability and metabolizable energy (ME) of the diet, apparent total tract digestibility (ATTD) of nutrients and energy, intestinal fermentation products, and fecal microbiota in dogs. Four diets containing 0, 70, 140, and 210 g/kg of HPDDG were manufactured. To evaluate the ME and the ATTD of macronutrients of HPDDG itself, an additional test diet was manufactured containing 70% of the control diet formula (0 g/kg) and 300 g/kg of HPDDG. Fifteen adult Beagle dogs were distributed in a randomized block design, with two periods of 15 d each (n = 6). The HPDDG digestibility was obtained using the Matterson substitution method. For the palatability test, 16 adult dogs were used, comparing the diets: 0 vs. 70 g/kg of HPDDG and 0 vs. 210 g/kg of HPDDG. The ATTD of HPDDG were: dry matter = 85.5%, crude protein = 91.2%, and acid-hydrolyzed ether extract = 84.6% and the ME content was 5,041.8 kcal/kg. The ATTD of macronutrients and ME of the diets and the fecal dry matter, score, pH, and ammonia of the dogs did not differ among treatments (P > 0.05). There was a linear increase in the fecal concentrations of valeric acid with the inclusion of HPDDG in the diet (P < 0.05). Streptococcus and Megamonas genera reduced linearly (P < 0.05), and Blautia, Lachnospira, Clostridiales, and Prevotella genera showed a quadratic response to the inclusion of HPDDG in the diet (P < 0.05). Alpha-diversity results showed an increase (P < 0.05) in the number of operational taxonomic units and Shannon index and a trend (P = 0.065) for a linear increase in the Chao-1 index with the dietary inclusion of HPDDG. Dogs preferred the 210 g/kg diet over the 0 g/kg HPDDG diet (P < 0.05). These results demonstrate that the HPDDG evaluated does not affect the utilization of nutrients in the diet, but it may modulate the fecal microbiome of dogs. In addition, HPDDG may contribute to diet palatability for dogs.

Apparent total tract macronutrient digestibility of mildly cooked human-grade vegan dog foods and their effects on the blood metabolites and fecal characteristics, microbiota, and metabolites of adult dogs.

Vegan, mildly cooked, and human-grade dog foods are becoming more popular, as beliefs and views of pet owners change. To our knowledge, however, dog studies have not examined the digestibility of commercial vegan diets. Therefore, the objective of this study was to determine the apparent total tract digestibility (ATTD) of mildly cooked human-grade vegan dog foods and their effects on blood metabolites and fecal microbiota, characteristics, and metabolites of adult dogs consuming them. Three commercial dog foods were tested. Two were mildly cooked human-grade vegan dog diets, while the third was a chicken-based extruded dog diet. Twelve healthy adult female beagles (7.81 ± 0.65 kg; 7.73 ± 1.65 yr) were used in a replicated 3 × 3 Latin Square design. The study consisted of three experimental periods, with each composed of a 7 d diet adaptation phase, 15 d of consuming 100% of the diet, a 5 d phase for fecal collection for ATTD measurement, and 1 d for blood collection for serum chemistry and hematology. During the fecal collection period, a fresh sample was collected for fecal scoring and dry matter, pH, metabolite, and microbiota measurements. All data were analyzed using the Mixed Models procedure of SAS (version 9.4). All three diets were shown to be highly digestible, with all macronutrients having digestibility values above 80%. The vegan diets had higher (P < 0.001) ATTD of fat, but lower (P < 0.05) ATTD of organic matter than the extruded diet. Dogs consuming the vegan diets had lower circulating cholesterol (P < 0.001), triglyceride (P < 0.001), and platelet (P < 0.009) concentrations and lower (P < 0.010) blood neutrophil percentages than dogs consuming the extruded diet. Dogs consuming vegan diets had lower (P < 0.001) fecal dry matter percentages, lower (P < 0.001) fecal phenol and indole concentrations, and higher (P = 0.05) fecal short-chain fatty acid concentrations than those consuming the extruded diet. Fecal bacterial alpha and beta diversities were not different (P > 0.05) among diets, but dogs consuming vegan diets had altered (P < 0.05) relative abundances of nearly 20 bacterial genera when compared with those consuming the extruded diet. In conclusion, the mildly cooked human-grade vegan dog foods tested in this study performed well, resulting in desirable fecal characteristics, ATTD, and serum chemistries. The vegan diets tested also led to positive changes to serum lipids and fecal metabolites, and interesting changes to the fecal microbial community.

Comparing the standardized amino acid digestibility of an alternative protein source with commercially available protein-based ingredients using the precision-fed cecectomized rooster assay.

Using single-cell-based proteins in pet foods is of interest, but little testing has been done. Therefore, our objective was to determine the amino acid (AA) digestibilities, assess protein quality of a novel microbial protein (MP) (FeedKind), and compare it with other protein-based ingredients using the precision-fed cecectomized rooster assay. Test ingredients included: MP, chicken meal (CM), corn gluten meal (CGM), pea protein (PP), and black soldier fly larvae. Thirty cecectomized roosters (n = 6/ingredient) were randomly assigned to test ingredients. After 24 h of feed withdrawal, roosters were tube-fed 15 g test ingredient and 15 g corn, and then excreta were collected for 48 h. Endogenous AA corrections were made using additional roosters. Digestible indispensable AA score (DIAAS)-like values were calculated to determine protein quality according to Association of American Feed Control Officials (AAFCO), The European Pet Food Industry Federation, and National Research Council reference values for growing and adult dogs and cats. Data were analyzed using the Mixed Models procedure of SAS 9.4, with P ≤ 0.05 being significant. All reactive lysine:total lysine ratios, an indicator of heat damage, were higher than 0.9, except for CM (0.86). Digestibility of indispensable and dispensable AA were >85% and >80% for MP, respectively, with indispensable AA digestibilities being >80% for all other ingredients. In general, CGM had the highest, while CM had the lowest AA digestibilities. Two exceptions were lysine and tryptophan. Lysine digestibility for MP was higher than that of all other ingredients, while tryptophan digestibility for MP was higher than that of CM, CGM, and PP. Threonine digestibility was highest for CGM and MP. Valine digestibility was highest for CGM, PP, and MP. DIAAS-like calculations identified limiting AA of each ingredient and depended on the reference used and life stage and species of animal. Using AAFCO guidelines, all DIAAS-like values for MP were >100 suggesting that it could be used as the sole source of protein in adult dog and cat diets; only methionine had DIAAS-like values <100 for growing kittens. For dogs, limiting AA was most commonly methionine, threonine, and tryptophan in the other protein sources. For cats, limiting AA was most commonly lysine and methionine. Lysine was severely limited in CGM across all life stages considered. Further research in dogs and cats is necessary, but our data suggest that the MP tested has high AA digestibilities and is a high-quality protein source that may be useful in pet foods.

Nutritional evaluation of new alternative types of dog foods including raw and cooked homemade-style diets.

New alternative types of pet foods such as raw and cooked homemade-style diets containing human food ingredients have been introduced due to a trend of pet humanization and diversification of consumer needs. To evaluate nutritional adequacy of new alternative types of dog foods containing human food ingredients as maintenance diets for dogs. Eleven homemade-style foods for adult dogs were purchased from online channel in Korea and analyzed to evaluate nutritional adequacy for adult dogs. Nutrients analyzed included crude protein, amino acids, crude fat, fatty acids, and minerals. Crude protein and amino acids in all products satisfied Association of American Feed Control Officials (AAFCO) requirements. Crude fat in one of 11 products did not meet AAFCO requirements. The most deficient minerals were selenium (10 of 11, 90.9%), copper (five of 11, 45.5%), zinc (five of 11, 45.5%), potassium (three of 11, 27.3%), calcium (three of 11, 27.3%), iron (two of 11, 18.2%), and magnesium (one of 11, 9.1%). Six products were not in the range of the recommended Ca:P ratio in AAFCO dog food maintenance nutrient profiles. This study performed nutritional evaluation of raw and cooked homemade-style foods as maintenance diets for adult dogs. Some nutritional inadequacies were observed including some minerals, Ca:P ratio, and omega-6:omega-3 fatty acid ratio, although three products (26.2%) satisfied the AAFCO standard except selenium. Overall, the data suggest a need for accurate nutritional adequacy statement for consumers based on proper methods to validate the formula.

Evaluation of corn-fermented protein as a dietary ingredient in extruded dog and cat diets.

Most pet foods utilize traditional ingredients like corn, wheat, and soy. These ingredients and other grains, such as distillers dried grains (DDG), have been used by the pet food industry. Corn-fermented protein (CFP) is a nutrient-dense enhancement on DDG but has not been evaluated in pet food. Therefore, it was the objective of this study to determine the effect of CFP in the production of extruded pet diets, and to determine the effect on nutrient utilization (digestibility) and stool consistency in dogs, and palatability in dogs and cats. Experimental diets with treatment protein sources (corn gluten meal [CGM], soybean meal [SBM], and CFP) were produced in triplicate using a single-screw extruder. Processing parameters and kibble samples were collected at timed intervals during diet production. Kibbles were evaluated for physical dimension and texture. No differences (P > 0.05) were observed in any physical dimension or texture parameters evaluated, with exception of radial expansion, which was lower (P < 0.05) for CFP kibble compared to others. The CFP kibble required a smaller (P < 0.05) mass restriction valve opening, to keep similar bulk density among dietary treatments. However, there was no difference (P > 0.05) in specific mechanical energy among treatments during diet production. Twelve beagles were fed the experimental diets in a 3 × 3 replicated Latin Square design in which four dogs were randomly assigned to each of three treatments for each period. Diets were formulated to be isonitrogenous and were supplemented with titanium dioxide to serve as an external marker in order to estimate apparent total tract digestibility. Dogs were housed individually and fed twice daily, and water was available ad libitum. Feces were collected after feedings. The diet produced with CGM was more digestible (P < 0.05) than CFP and SBM for dry matter, organic matter, crude protein, crude fat, and gross energy. Further, the CFP diet was also less (P < 0.05) digestible than the SBM diet for dry matter and organic matter. Dogs fed the diet containing CFP had higher (P < 0.05) fecal mass than those fed SBM and CGM. The CFP diet also resulted in a higher fecal score (P < 0.05) than those fed diets with the CGM diet, but similar (P > 0.05) to the SBM diet. For palatability assessment, dogs had a preference (P < 0.05) for CGM over SBM or CFP, but cats showed a preference (P < 0.05) for SBM and CFP over CGM. Results indicate that CFP is acceptable for use in dog and cat diets. Further research should be conducted to evaluate the use of these ingredients at lower inclusion levels.

Amino acid digestibility and nitrogen-corrected true metabolizable energy of mildly cooked human-grade vegan dog foods using the precision-fed cecectomized and conventional rooster assays.

The pet food market is constantly changing and adapting to meet the needs and desires of pets and their owners. One trend that has been growing in popularity lately is the feeding of fresh, human-grade foods. Human-grade pet foods contain ingredients that have all been stored, handled, processed, and transported in a manner that complies with regulations set for human food production. While most human-grade pet foods are based on animal-derived ingredients, vegan options also exist. To our knowledge, no in vivo studies have been conducted to analyze the performance of human-grade vegan diets. Therefore, the objective of this study was to investigate the amino acid (AA) digestibility and nitrogen-corrected true metabolizable energy (TME n ) of mildly cooked human-grade vegan dog foods using precision-fed cecectomized rooster and conventional rooster assays. Three commercial dog foods were tested. Two were mildly cooked human-grade vegan dog diets (Bramble Cowbell diet (BC); Bramble roost diet (BR)), while the third was a chicken-based extruded dog diet (chicken and brown rice recipe diet (CT)). Prior to the rooster assays, both mildly cooked diets were lyophilized, and then all three diets were ground. Diets were fed to cecectomized roosters to determine AA digestibility, while conventional roosters were used to determine TME n . All data were analyzed using the mixed models procedure of SAS (version 9.4). The majority of indispensable and dispensable AA across all diets had digestibilities higher than 80%, with a few exceptions (BC: histidine, lysine, threonine, and valine; BR: histidine). The only difference in indispensable AA digestibility among diets was observed with tryptophan, with its digestibility being higher (P = 0.0163) in CT than in BC. TME n values were higher (P = 0.006) in BC and BR (4.55 and 4.66 kcal/g dry matter, respectively) than that in CT (3.99 kcal/g dry matter). The TME n /GE was also higher (P = 0.0193) in BR than in CT. Metabolizable energy (ME) estimates using Atwater factors accurately estimated the energy content of CT, but modified Atwater factors and the predictive equations for ME recommended by the National Research Council underestimated energy content. All calculations underestimated the measured TME n values of BC and BR, with Atwater factors being the closest. Although testing in dogs is required, these data suggest that mildly cooked human-grade vegan dog diets are well-digested. Moreover, TME n data suggest that existing methods and equations underestimate the ME of the mildly cooked human-grade vegan foods tested.

Effects of extruded pet foods containing dried yeast (Saccharomyces cerevisiae) on palatability, nutrient digestibility, and fecal quality in dogs and cats.

Global protein shortages and sustainability concerns have increased consumer demand for non-animal-derived protein. Dried whole-cell yeast (Saccharomyces cerevisiae) may be a suitable alternative to rendered protein meals in pet foods. The objective of this study was to investigate the effects of dried yeast in dog and cat foods on indicators that pet parents typically use to evaluate the suitability of a food for their pet. For this evaluation, two dog and two cat dry extruded diets were formulated. For each species, the test diet contained 10% dried yeast (Yeast) and the control diet was devoid of yeast (Control). Palatability, apparent total tract nutrient digestibility, and fecal quality of the foods were assessed in dogs and cats. Urine pH and specific gravity were measured in cats as indicators of urinary tract health. In dogs, the Yeast diet showed equivalent or better palatability compared to the Control diet based on total food consumption (P = 0.06), average daily consumption (day 1, P = 0.10; day 2, P = 0.54), and first choice preference over 2 consecutive days (P = 0.005). Cats showed a strong preference for the Yeast diet with more than double the consumption during the 2-d test period (P = 0.001). More cats showed a first-choice preference for the Yeast diet (24 vs. 16), but the difference was not statistically significant (P = 0.21). There were no significant differences in stool quality or nutrient digestibility when fed Yeast vs. Control diets to the dogs and cats (P > 0.05). All cats produced urine with pH and specific gravity values within the normal range, though specific gravity was lower in the Control group (P = 0.003). This study provides support for the acceptability and digestibility of dog and cat diets containing dried yeast as an alternative protein source.

A comparison of summer insectivory among four sympatric mesocarnivores on Izushima, a small island in northern Japan

Abstract Limited resources intensify interspecific competition and constrain the survival and distribution of species. A restricted, spatially isolated, small island can also pronounce this effect, as predicted in the island biogeography. This study compared the summer diets of sympatric carnivores, red foxes, raccoon dogs, Japanese martens, and Japanese weasels on the small island Izushima and evaluated niche partitioning, especially focusing on their insectivory. The results showed that insects were the main summer food source for all four species, with a significant overlap in their diets. However, in-depth investigation on insectivory down to the level of species and genera revealed that the species differences were more pronounced. Raccoon dogs frequently fed on ground-dwelling beetles, and Japanese martens fed on several arboreal beetles, while red foxes were less dependent on insects and more biased toward larger prey such as mammals and birds, and Japanese weasels foraged more on smaller prey, thereby reflecting niche partitioning between these species owing to differences in foraging ecology under the constrains of their body sizes.

Home-cooked diets cost more than commercially prepared dry kibble diets for dogs with chronic enteropathies

Nutrition plays a fundamental role in the management of canine chronic enteropathies (CCEs). Dog owners may elect to feed home-cooked diets (HCDs) rather than veterinary commercially prepared diets (CPDs) because of perceived lower costs. There is a paucity of data comparing costs of these options. We hypothesize there will be differences in costs between complete and balanced HCDs and nutritionally comparable CPDs. 6 Home-cooked diets. Six HCD recipes (2 highly digestible, 2 limited antigen, 2 low-fat) were formulated by 2 board-certified veterinary nutritionists to mimic the nutritional and ingredient profiles of veterinary CPDs for management of CCEs. The cost (in US$ on a per 100 kilocalorie [kcal] basis) of each recipe was determined via collection of ingredient prices from 3 grocery stores combined with supplement prices from online retailers. Prices of CPDs were obtained from a national online retailer. Maintenance energy requirements of 1.6 X (70 X BWkg0.75), where BWkg represents body weight in kilograms, were calculated for 3 dog sizes (5, 20, and 40 kg), and costs of feeding maintenance energy requirements with HCDs versus dry and canned CPDs were compared with a Kruskal-Wallis test and post hoc testing. The median costs of all dry and canned CPDs and HCDs were $0.29 (range, $0.18 to $0.46), $1.01 (range, $0.77 to $1.20), and $0.55 (range, $0.35 to $1.14), respectively. Feeding complete and balanced HCDs cost more than feeding dry CPDs (P < .001), but not canned CPDs (P > .99). Dry CPDs cost the least for nutritional management of CCEs. There is a wide range of costs for both CPDs and HCDs.

Weight measurements result in improved accuracy and precision in preparation of cooked homemade diets for dogs.

Accurate measurement of ingredients for cooked homemade diets helps ensure diets are complete and balanced. Studies have demonstrated measuring dry dog food with measuring cups results in significant inaccuracy. Therefore, measuring ingredients by volume when preparing these diets may be inaccurate. The purpose was to determine the accuracy of preparing cooked homemade diets by measuring ingredients by volume (measuring cups and spoons) or weight (digital gram scale with a syringe for measuring oil only). 42 diet samples prepared by 21 participants. 21 participants were instructed on homemade diet preparation based on weight or volume measurement methods. Diet samples underwent proximate analysis and mineral analysis. Data, expressed on a dry matter basis (DMB) and an energy density basis (EDB), from both groups were compared to the anticipated nutrient profile to determine which method resulted in more accuracy. Data from individual samples within each group were compared to each other to determine the precision of both methods. Weight measurements were more precise for crude protein, crude fat, nitrogen-free extract, and potassium (DMB and EDB) and more accurate for ash (DMB and EDB) and iron (EDB). Comparatively, volume measurements were more precise for ash (DMB) and more accurate for iron (DMB). Findings suggest weight measurements should be utilized to prepare cooked homemade diets for dogs to promote precision and accuracy.

High levels of dietary digestible protein transiently promote beneficial bacteria in adult dog feces

Nowadays, many commercial dog diets select the ingredients not only to meet the needs of the individual and maintain a balance between nutrition/microbiome/health; fiber and protein quality is known to be one of the most important factors in this balance. Diets high in low digestible protein tend to favor microorganisms that when fermenting amino acids generate substances that induce inflammation, while high digestible protein and fermentable fibers have been related to beneficial bacteria. The study's objective was to identify changes in the relative abundance of specific microorganisms (Clostridium perfringens, Enterococcus faecium, Lactobacillus salivarius, Bacteroides fragilis and Fusobacterium varium) by PCR (polymerase chain reaction), associated with two diets of different quality and digestibility. Twenty adult dogs were used, divided into two groups, the first one fed with a high digestibility diet (HD) (n = 10), the second one with a low digestibility diet (LD) (n = 10). After 3 days of adaptation to the diet, fecal samples were taken at days 15 and 30. The results showed that the high-quality diet promotes a transient increase (15 days) in the relative abundance of F. varium and E. faecium, as well as a persistent increase in that of L. salivarius and B. fragilis until day 30. Apparently, however, healthy adult dogs eventually balance their fecal microbiota, regardless of the dietary protein level and digestibility. Therefore, it is difficult to identify clear patterns of the ideal dietary profile in this species.

Effects of black soldier fly larvae as protein or fat sources on apparent nutrient digestibility, fecal microbiota, and metabolic profiles in beagle dogs.

Black soldier fly (Hermetia illucens) larvae (BSFL) act as a biological system converting organic waste into protein and fat with great potential application as pet food. To evaluate the feasibility of BSFL as a protein and fat source, 20 healthy beagle dogs were fed three dietary treatments for 65 days, including (1) a basal diet group (CON group), (2) a basal diet that replaced 20% chicken meal with defatted black soldier fly larvae protein group (DBP group), and (3) a basal diet that replaced 8% mixed oil with black soldier fly larvae fat group (BF group). This study demonstrated that the serum biochemical parameters among the three groups were within the normal range. No difference (p > 0.05) was observed in body weight, body condition score, or antioxidant capacity among the three groups. The mean IFN-γ level in the BF group was lower than that in the CON group, but there was no significant difference (p > 0.05). Compared with the CON group, the DBP group had decreasing (p < 0.05) apparent crude protein and organic matter digestibility. Furthermore, the DBP group had decreasing (p < 0.05) fecal propionate, butyrate, total short-chain fatty acids (SCFAs), isobutyrate, isovalerate, and total branched-chain fatty acids (BCFAs) and increased (p < 0.05) fecal pH. Nevertheless, there was no difference (p > 0.05) in SCFAs or BCFAs between the CON and BF groups. The fecal microbiota revealed that Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were significantly enriched in the DBP group, and Terrisporobacter and Ralstonia were significantly enriched in the BF group. The fecal metabolome showed that the DBP group significantly influenced 18 metabolic pathways. Integrating biological and statistical correlation analysis on differential fecal microbiota and metabolites between the CON and DBP groups found that Lachnoclostridium, Clostridioides, and Enterococcus were positively associated with biotin. In addition, Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were positively associated with niacinamide, phenylalanine acid, fumaric acid, and citrulline and negatively associated with cadavrine, putrescine, saccharopine, and butyrate. In all, 20% DBP restrained the apparent CP and OM digestibility, thereby affecting hindgut microbial metabolism. In contrast, 8% BF in the dog diet showed no adverse effects on body condition, apparent nutrient digestibility, fecal microbiota, or metabolic profiles. Our findings are conducive to opening a new avenue for the exploitation of DBP and BF as protein and fat resources in dog food.

Environmental impact of diets for dogs and cats

Food production is responsible for almost one-quarter of the environmental impact and, therefore, its importance regarding sustainability should not be overlooked. The companion animal population is increasing, and an important part of pet food is composed of ingredients that have a high environmental impact. This study aimed to evaluate the impact of dry, wet, and homemade pet diets on greenhouse gas emission, land use, acidifying emission, eutrophying emissions, freshwater withdrawals, and stress-weighted water use. The wet diets were responsible for the highest impact, and dry diets were the type of diet that least impacted the environment, with a positive correlation between the metabolizable energy provided by animal ingredients and the environmental impact. It is necessary to consider the environmental impact of pet food since it is significant, and the population of pets tends to increase.

Effects of poultry by-products inclusion in dry food on nutrient digestibility and fecal quality in Beagle dogs.

Animal by-product meals show large variability in diet digestibility. This study aimed to provide information on including bone protein meal (BPM) or feather meal (FM) in extruded dog diets with regard to digestibility and fecal characteristics in two trials. In the first trial, compared to the control (BPM0), 6, 12, and 24% of the basic diets were replaced by BPM (BPM6, BPM12, and BPM24, respectively). In the second trial, in comparison to the control (FM0), 5, 10, and 20% of the basic diets were replaced by FM (FM5, FM10, and FM20, respectively). In both trials, six Beagle dogs (BW 17.3±2.14 and 18.1±2.04 kg for trials 1 and 2, respectively) participated in a crossover experiment design. Five days were used as wash-out before each experimental period for each trial. The fecal consistency scores were based on a 5-point scale (1 = very hard, 2 = solid, well formed "optimum", and 5 = watery diarrhea). In the first trial, results showed that the apparent digestibility of dry matter, crude protein, and crude fat was significantly lower for dogs fed BPM6 compared to those fed BPM24. There was a lower number of dogs with a fecal consistency score value &gt; 2 (16.7%) among those fed BPM6 (median = 2, Interquartile range (IQR) = 0) compared to those fed BPM24 (83.3%). The fecal dry matter content was significantly (p &lt; 0.05) the highest (39.4%±2.15) for dogs fed BPM6. In the second trial, the data revealed that dogs fed FM0 had significantly (p &lt; 0.05) the highest organic matter digestibility (87.2%±1.05), while dogs fed FM20 had significantly (p &lt; 0.05) the lowest crude fat digestibility (95.0%±0.95). Inclusion of FM at 10% or 20% in the diet decreased fecal dry matter significantly (29.0%±2.10 and 27.9%±2.46, respectively) compared to those animals offered FM0 (31.1%±2.56). Among those dogs fed FM0 and FM5, there was a lower significant number of dogs with a fecal score value &gt; 2 (16.7% and 16.7%, respectively; p &lt; 0.05). While the fecal score was significantly a higher (median = 4, IQR = 0) for dogs fed FM20. Including FM at any level in the diet resulted in significantly higher levels of iso-butyric and iso-valeric acids compared to FM0. These findings in both trials suggest that apparent crude protein digestibility was not affected when diets containing BPM up to 24% and FM up to 20% were offered, but fecal quality was reduced.

Extrusion and product parameters for extruded dog diets with graded levels of whole soybeans

Increasing the fat amount of the ration during extrusion can negatively affect product density and product expansion. Ingredients, like whole soybeans (WSB), which are high in fat may increase energy density while avoiding production issues. The objective of this study was to determine the effect of WSB on extrusion and product characteristics of dry expanded dog food. Experimental diets were extruded with 0, 100, 200, and 300 g/kg, as fed WSB. The processing conditions during extrusion were kept constant across all treatments. Processing outputs, trypsin inhibitor, urease, and phytic acid concentrations were analyzed. Single degree of freedom contrasts were used for statistical analysis and significance at α = 0.05. As WSB increased, the extruder load, die pressure and temperature, and specific mechanical energy (SME) decreased linearly (P < 0.05). The bulk density of the products increased linearly (P < 0.05) while the kibble sectional expansion index (SEI) decreased linearly (P < 0.05) as WSB increased. Post-extrusion, trypsin inhibitor and urease activity decreased, but trypsin inhibitor was not eliminated. In conclusion, the increased inclusion level of WSB changed processing conditions and outputs as a result of the intrinsic and intact fat content. Increasing energy input in processing may destroy anti-nutritional factors completely when WSB are included in diets.

Infographic: Digestible indispensable amino acid scores of animal and plant ingredients potentially used in dog diet formulation: How this protein quality metric is affected by ingredient characteristics and reference amino acid profile.

Infographic: Digestible indispensable amino acid scores of animal and plant ingredients potentially used in dog diet formulation: How this protein quality metric is affected by ingredient characteristics and reference amino acid profile.

Effects of an Herbal Source of Choline on Diet Digestibility and Palatability, Blood Lipid Profile, Liver Morphology, and Cardiac Function in Dogs.

Simple SummaryCholine is an essential nutrient for dogs, and its dietary supplementation is usually made using choline chloride. However, this compound is highly hygroscopic—meaning it absorbs moisture from the air—which makes it difficult to manipulate during animal food production. Stable herbal additives rich in phosphatidylcholine may be used as an alternative source of choline. In light of this, this study compared the effects of an herbal source of choline with choline chloride on diet digestibility and palatability, blood metabolites, liver morphology, and cardiac function in adult dogs. Our results suggest that the herbal source of choline is a possible substitute for choline chloride in dog diets, in addition to reducing the activity of liver enzymes, total cholesterol, and serum triglycerides. This study is relevant to the pet food market since it concerns pet owners interested in natural alternative foods.We aimed to evaluate the effects of an herbal source of choline on the coefficients of total tract apparent digestibility (CTTAD), diet palatability, fecal characteristics, blood variables, liver morphology, and cardiac function of dogs. Sixteen adult dogs were randomly assigned to two groups (n = 8) which were fed two different diets for 45 days: control, containing 0.28% choline chloride 60, and test, containing 0.14% of an herbal source of choline. Feces were collected between days 39 and 44 to determine nutrient CTTAD and fecal characteristics. On days 0 and 45, blood samples were collected and the liver morphology was evaluated. Cardiac function, in turn, was evaluated only on day 45, and the palatability test was performed on two consecutive days (n = 32). There were no changes in nutrient CTTAD, diet palatability, or fecal characteristics of dogs fed the test diet (p > 0.05). However, on day 45, dogs fed the test diet showed lower (p < 0.05) serum total cholesterol, triglycerides, alkaline phosphatase, and alanine aminotransferase when compared to the control group. We concluded that the herbal source of choline can be a possible substitute for choline chloride in dog nutrition.

122 Human-Grade dog Diets Dramatically Shift the Fecal Microbiome of Healthy Adult Dogs

Abstract Human-grade pet foods have been shown to be highly palatable and digestible, resulting in reduced stool volume, but their impact on the gut microbiome has not been well studied. Therefore, our objective was to compare the fecal characteristics and microbiome of dogs consuming a human-grade or extruded kibble diet. Female beagles (n = 20; BW = 10.25±0.82 kg; age = 3.85±1.84 yr) were used in a completely randomized design. The diets tested were: 1) Chicken and Brown Rice Recipe [extruded; Blue Buffalo (BB)] and 2) Chicken and White Rice [human-grade; Just Food for Dogs (JFFD)]. The study consisted of a 4-week baseline when all dogs were fed BB, and a 12-week treatment phase when dogs were randomized to eat each diet (n=10/group). After the baseline and treatment phases, fresh fecal samples were collected for fecal pH, dry matter (DM), score, and microbiota analysis. Fecal bacterial DNA was extracted and shotgun sequencing was conducted using an Illumina NovaSeq, generating over 1.8 billion reads. Taxonomic and pathway abundances were calculated using MetaPhlan and HUMAnN, respectively. Fecal pH and DM were less (p&amp;lt; 0.05) in dogs fed JFFD than those fed BB, but fecal scores were not affected by diet. PCoA plots based on Bray-Curtis distances of bacterial genera and species showed some shifts over time in dogs fed BB, but much greater shifts in those fed JFFD. JFFD increased (adj p&amp;lt; 0.05) the relative abundances of 4 bacterial genera, 11 bacterial species, 129 KEGG pathways, and 167 Maaslin pathways and decreased (adj p&amp;lt; 0.05) the relative abundances of 16 bacterial genera, 25 bacterial species, 37 KEGG pathways, and 87 Maaslin pathways. In conclusion, the human-grade food tested vastly shifted the fecal microbiome. More research is needed to link taxonomic and gene content shifts to ingredient inclusion, nutrient concentrations, and health outcomes.

PSXI-1 Influence of Graded Levels of Microbially Enhanced Protein on Processing and Expansion of Extruded dog Foods

Abstract Dry expanded kibbles with ingredients that bring extra nutrition and health benefits are much better received than those which are simply an economic choice by manufacturers. Microbially enhanced protein (MEP) from soybeans, a fermented ingredient, may promote utilization. The objective of this study was to determine the influence of increasing levels of MEP on extrusion processing parameters and kibble characteristics. Four dietary treatments were evaluated which differed by level of MEP in exchange for soybean meal (15%; SBM) at 5, 10 and 15% (5MEP, 10MEP and 15MEP, respectively). The four diets were produced on a single-screw extruder with processing data and samples collected every 15 minutes. Results were analyzed as a completely randomized design by one-way ANOVA and treatment means were separated by Tukey’s test using R open-source software. Feed rate and extruder waterflow rate were not different among treatments. However, motor power, shaft speed and specific mechanical energy (SME) was least for 5MEP (P&amp;lt; 0.05, 30.1 KW, 322.5 rpm and 38.4 kW hr/ton, respectively). The SME for SBM was also less (P&amp;lt; 0.05) than 10MEP and 15 MEP (43.72, vs 47.4 and 47.0 kW hr/ton, respectively), but shaft speed did not differ among these treatments. Both kibble diameter and sectional expansion index (SEI) of 5MEP (11.9 mm and 10.0 mm2, respectively) were greater (P&amp;lt; 0.05) than SBM (11.0 mm and 7.6 mm2, respectively), 10 MEP (11.4 mm and 8.6 mm2, respectively) and 15MEP (11.5 mm and 8.9 mm2, respectively). While thickness of 5MEP was thinner (P&amp;lt; 0.05) than SBM, 10MEP and 15MEP (5.73 vs average 6.20 mm, respectively). Bulk density was greater (P&amp;lt; 0.05) for SBM than 5MEP (408.7 vs 374.0 kg/m-3, respectively), while10MEP and 15MEP (388.8 and 392.7 kg/m-3, respectively) were similar to both extremes. Addition of MEP in extruded dog diets improved expansion and reduced energy requirement, but the benefits may be less at greater inclusion levels.