Early-Life Factors Can Predict Obesity in Adult Dogs
Researchers have identified several early predictive factors for obesity in adult female beagles, adding to the current body of knowledge on canine obesity risk factors.
In a study recently published in BMC Veterinary Research, researchers identified several early predictive factors for obesity in adult female beagles. This study, according to the authors, was “the first longitudinal study in growing dogs to investigate predictive factors that could explain becoming overweight and obese in adulthood.”
Nearly 50% of pet dogs are either overweight or obese, often due to increased energy intake and decreased energy expenditure. Unfortunately, many dogs on weight loss programs either don’t reach their target weight or cannot maintain long-term weight loss.
Previous studies have identified risk factors for canine obesity, including neutering and sedentary lifestyle. Other studies have reported the influence of various plasma biomarkers on energy homeostasis in obese and normal-weight dogs.
Human studies have identified early predictive factors for obesity, such as high gestational weight gain. Few veterinary studies, though, have evaluated whether early growth patterns and plasma biomarker concentrations predict adult canine obesity.
The authors studied 24 female beagles from birth to 24 months. All dogs came from multiple litters at a breeding center, were fed and raised identically, and were spayed at 8 months. Early-life data, including gestational weight gain and body weight (BW) of parents at mating, were collected. At designated time points, biometric data were also collected:
- Withers height
- Fat-free mass
- Pelvic circumference
- Fat mass percentage
- Body condition score (BCS; 9-point scale)
Blood samples were collected to measure plasma concentrations of various biomarkers, including glucose, ghrelin, leptin, and inflammatory markers. Energy intake and resting energy expenditure were also measured.
After analyzing several biometric parameters at 24 months of age, the authors categorized the dogs into 3 groups—ideal weight (IW), slightly overweight (OW1), and overweight (OW2)—for additional data analysis.
From 7 to 24 months of age, BCS values remained relatively stable in IW dogs but increased steadily in OW1 and OW2 dogs. Importantly, the authors determined that at 7 months of age, BCS clearly differentiated the groups. This finding indicated that BCS at 7 months could be used as an early predictor of adult obesity.
Although parental characteristics did not significantly influence differences between groups, maternal BW significantly and positively correlated with fat-free mass at 24 months.
Birth weights were generally similar across groups. Over time, though, BW and growth rate significantly varied between groups. For example, from 6 to 24 months of age, BW was significantly higher in OW2 than in IW or OW1 dogs. Importantly, growth rate within the first 2 weeks of life (GR2w) was significantly higher in OW2 than IW or OW1 dogs; the authors identified GR2w as another early predictor of adult obesity.
Energy intake and resting energy expenditure (adjusted for fat-free mass) significantly decreased across groups between 7 and 10 months of age, which correlated to when the dogs were spayed. However, resting energy balance values were significantly higher in OW2 than IW and OW1 dogs during this time frame, suggesting poor energy balance control with excessive weight gain.
Concentrations of most of the analyzed plasma biomarkers were not significantly different between groups. Notably, postprandial acylated ghrelin levels decreased most rapidly and significantly in IW dogs, suggesting that slow postprandial acylated ghrelin suppression in overweight dogs could encourage overeating.
The authors concluded that BCS at 7 months of age and GR2w were early predictors of adult canine obesity. Awareness of these early risk factors could help breeders and veterinarians make dietary adjustments in neonatal and adolescent dogs at risk for obesity. Larger studies in different breeds and sexes will be needed, the authors noted, before practical recommendations can be implemented.
Dr. JoAnna Pendergrass received her Doctor of Veterinary Medicine degree from the Virginia-Maryland College of Veterinary Medicine. Following veterinary school, she completed a postdoctoral fellowship at Emory University’s Yerkes National Primate Research Center. Dr. Pendergrass is the founder and owner of JPen Communications, a medical communications company.