Different Diet Energy Levels Alter Body Condition, Glucolipid Metabolism, Fecal Microbiota and Metabolites in Adult Beagle Dogs

Abstract

Diet energy is a key component of pet food, but it is usually ignored during pet food development and pet owners also have limited knowledge of its importance. This study aimed to explore the effect of diet energy on the body condition, glucolipid metabolism, fecal microbiota and metabolites of adult beagles and analyze the relation between diet and host and gut microbiota. Eighteen healthy adult neutered male beagles were selected and randomly divided into three groups. Diets were formulated with three metabolizable energy (ME) levels: the low-energy (Le) group consumed a diet of 13.88 MJ/kg ME; the medium-energy (Me) group consumed a diet of 15.04 MJ/kg ME; and the high-energy (He) group consumed a diet of 17.05 MJ/kg ME. Moreover, the protein content of all these three diets was 29%. The experiment lasted 10 weeks, with a two-week acclimation period and an eight-week test phase. Body weight, body condition score (BCS), muscle condition score (MCS) and body fat index (BFI) decreased in the Le group, and the changes in these factors in the Le group were significantly higher than in the other groups (p < 0.05). The serum glucose and lipid levels of the Le and He groups changed over time (p < 0.05), but those of the Me group were stable (p > 0.05). The fecal pH of the Le and He groups decreased at the end of the trial (p < 0.05) and we found that the profiles of short-chain fatty acids (SCFAs) and bile acids (BAs) changed greatly, especially secondary BAs (p < 0.05). As SCFAs and secondary BAs are metabolites of the gut microbiota, the fecal microbiota was also measured. Fecal 16S rRNA gene sequencing found that the Me group had higher α-diversity indices (p < 0.05). The Me group had notably higher levels of gut probiotics, such as Faecalibacterium prausnitzii, Bacteroides plebeius and Blautia producta (p < 0.05). The diet–host–fecal microbiota interactions were determined by network analysis, and fecal metabolites may help to determine the best physical condition of dogs, assisting pet food development. Overall, feeding dogs low- or high-energy diets was harmful for glucostasis and promoted the relative abundance of pathogenic bacteria in the gut, while a medium-energy diet maintained an ideal body condition. We concluded that dogs that are fed a low-energy diet for an extended period may become lean and lose muscle mass, but diets with low energy levels and 29% protein may not supply enough protein for dogs losing weight.

Quantitative bile acid profiling in healthy adult dogs and pups from serum, plasma, urine, and feces using LC-MS/MS

“…Finally, feces BA do not primarily reflect the physiological BA pool but are more dependent on the metabolic activity of the microbiota, which typically exhibits large interindividual variability (10,(49)(50)(51). Of note, as many secondary BAs that result from the microbial degradation of primary BAs are reabsorbed and thus also appear in the blood, the blood compartment reflects the hepatic capacity of BA synthesis, conjugation, and transport, and in addition the metabolic activity of the microbiome (9, 36,52). In this context, the determination of DCA and its taurine-conjugated form (T-DCA), both of which could be robustly detected in all dogs in blood and feces, are interesting candidates for diagnostic BA measurements.…”

“…Additionally, Thakare et al (30) expanded the cross-species BA analysis up to eleven different species, also including beagle dogs. In most of these studies involving dogs, BA analysis was either presented individually across various matrices or as collective report combining several matrices, and most of these studies were performed only in mixed breeds or beagle dogs (17,(31)(32)(33)(34)(35)(36). However, the lack of BA profiling studies in different age groups, the low number of studies for healthy clinical patient collectives of very different dog breeds, and the poorly characterized dietary effects on the BA profile still limit our understanding of the physiological range in BA concentrations and abnormal values in disease conditions.…”

Preclinical Modeling of Metabolic Syndrome to Study the Pleiotropic Effects of Novel Antidiabetic Therapy Independent of Obesity

“…Previous studies have shown that consistent overfeeding of dogs with a high-calorie Western diet (WD) can lead to MetS, regardless of the diet's composition (Moinard et al, 2020;Xue et al, 2022). However, these investigations in dogs have primarily focused on the metabolic issues associated with obesity (Tvarijonaviciute et al, 2012b;Peña et al, 2014;Moinard et al, 2020;Sun et al, 2023;Vecchiato et al, 2023). In both dogs and humans, obesity triggers an adipose tissue redistribution that results in an increase in visceral (vs. subcutaneous) fat.…”

A Preclinical Model of Obesity-Independent Metabolic Syndrome for Studying the Effects of Novel Antidiabetic Therapy Beyond Glycemic Control

“…Previous studies suggest that consistently overfeeding dogs with high-calorie Western diets (WDs) leads to obesity and MetS, regardless of the diet composition (Moinard et al, 2020;Xue et al, 2022). Indeed, prior studies investigating the effects of WDs in dogs have primarily focused on metabolic dysfunction related to obesity (Tvarijonaviciute et al, 2012b;Peña et al, 2014;Moinard et al, 2020;Sun et al, 2023;Vecchiato et al, 2023). Within the context of obesity, both dogs and humans exhibit a redistribution of adipose tissue characterized by an increase in visceral fat, as opposed to subcutaneous fat.…”