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High-fat diet (HFD) successfully induced obesity in beagle dogs. (A) Schematic diagram of the experimental design process. Beagles were randomly divided into two groups, and then fed a HFD or a normal chow diet (NC) for 24 weeks. The obese dogs were evaluated by physical examination and laboratory and imaging examinations. Obese dogs were selected and randomly assigned to be fed with a weight-loss diet or control diet for an additional 8 weeks. (B) Analysis of body weight, body weight gain, and body condition scoring (BCS) in the HFD and NC groups at 0 and 24 weeks. n = 8 beagles/group. (C) Cross-sectional nuclear magnetic resonance imaging (MRI) analysis of the fat distribution in the HFD and NC groups at 0 and 24 weeks. Total adipose tissue (TAT) quantification was calculated based on the distributions of subcutaneous adipose tissue (SAT) (red arrow) and visceral adipose tissue (VAT) (white arrow). n = 5 beagles/group. Scale bar, 5 cm. (D) Representative images of H&E staining and comparison of morphological changes of adipose tissue between two groups of beagles after 24 weeks. n = 5 beagles/group. Scale bar, 100 μm. (E) The levels of TG, TC, and LDL in serum reflecting the blood lipids. n = 8 beagles/group. The data of body weight and body weight gains in panel (B) and the data in panels (C–E) are presented as the means ± SEMs and analyzed by Student’s two-tailed t-test. The data of BCS in panel (B) are presented as the means ± SEMs and analyzed by the Mann–Whitney U non-parametric test. *P < 0.05; **P < 0.01; ***P < 0.001. TG, triglyceride; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol.

High-fat diet (HFD) successfully induced obesity in beagle dogs. (A) Schematic diagram of the experimental design process. Beagles were randomly divided into two groups, and then fed a HFD or a normal chow diet (NC) for 24 weeks. The obese dogs were evaluated by physical examination and laboratory and imaging examinations. Obese dogs were selected and randomly assigned to be fed with a weight-loss diet or control diet for an additional 8 weeks. (B) Analysis of body weight, body weight gain, and body condition scoring (BCS) in the HFD and NC groups at 0 and 24 weeks. n = 8 beagles/group. (C) Cross-sectional nuclear magnetic resonance imaging (MRI) analysis of the fat distribution in the HFD and NC groups at 0 and 24 weeks. Total adipose tissue (TAT) quantification was calculated based on the distributions of subcutaneous adipose tissue (SAT) (red arrow) and visceral adipose tissue (VAT) (white arrow). n = 5 beagles/group. Scale bar, 5 cm. (D) Representative images of H&E staining and comparison of morphological changes of adipose tissue between two groups of beagles after 24 weeks. n = 5 beagles/group. Scale bar, 100 μm. (E) The levels of TG, TC, and LDL in serum reflecting the blood lipids. n = 8 beagles/group. The data of body weight and body weight gains in panel (B) and the data in panels (C–E) are presented as the means ± SEMs and analyzed by Student’s two-tailed t-test. The data of BCS in panel (B) are presented as the means ± SEMs and analyzed by the Mann–Whitney U non-parametric test. *P < 0.05; **P < 0.01; ***P < 0.001. TG, triglyceride; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol.

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Background and aims Overweight or obesity is one of the most prevalent health burdens in companion pets and predisposes subjects to multiple comorbidities and reduced longevity. Dietary management and sufficient exercise are effective options for weight loss but challenged by modern lifestyle and calorie control-triggered malnutrition. Therefore, t...

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... 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). ...
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... During feeding, it was found that dogs in the Le group could consume almost all of the 32 g/BW kg/d food, while dogs in the Me and He groups had varying degrees of leftovers, which may have been related to the fact that dogs can adjust their food intake according to their energy intake. A similar finding was obtained by Xue et al. [14], where adult beagle dogs lost 15 to 25% of their body weight after eight weeks of consuming a diet with ME of 13.54 or 12.93 MJ/kg diet, while no significant changes were observed after 24 weeks of consuming a dietary ME of 15.07 MJ/kg diet. ...
... The content of LDL-C in serum shows a significant positive correlation with the incidence of coronary heart disease, and it is an important index to evaluate the risk factors of individual coronary heart disease [74]. In canine obesity modeling and weight loss trials, high-fat diets were found to lead to a significant increase in serum CHO levels, while low-energy diets led to a decrease in CHO [13][14][15]75]. ...
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