The impact of an overweight body condition on pregnancy, parturition, and physical activity in the bitch.

Abstract

Lay abstract: Excessive body fat is suspected to negatively affect reproductive success in dogs, similar to other species. Thus, we aimed to determine if overweight dogs had negative pregnancy outcomes. Six overweight and 10 lean female dogs were monitored through pregnancy until the first four weeks of lactation. Lean dogs had higher baseline activity levels at home than overweight dogs. During pregnancy, lean dogs had a gradual decline in their activity that stayed low throughout lactation. Overweight dogs maintained their baseline activity levels throughout gestation, but increased during lactation. No differences were found between the two groups in embryonic growth rate, duration of labor, placental vasculature, or selected blood biomarker concentrations. We noted a potential clinically relevant higher early pregnancy loss and slower labor progression until the birth of the first puppy in overweight bitches, although this was not statistically significant. Although a relatively small number of dogs were included, the results point toward potential negative effects of obesity on canine reproductive performance.