Sleep Duration and Behaviours: A Descriptive Analysis of a Cohort of Dogs up to 12 Months of Age

SIMPLE SUMMARY: Sleep in dogs is a rarely studied but important behaviour. Changes in the pattern and duration of a dog’s sleep can reflect a dog’s wakeful experiences and how comfortable they are in their own environment. Little is known about normal sleep behaviours in dogs under 12 months of age. This study aimed to describe patterns of sleep and sleep-related behaviours (such as where the dog slept, how the dog was settled to sleep, sleep positions, and snoring) based on reports from owners of dogs aged 16 weeks and 12 months. For the statistical analysis, only dogs with data regarding sleep duration at both timepoints were used. Dogs aged 16 weeks slept for significantly longer during the day and in total over a 24 h period, but for less time during the night than dogs at 12 months. At both timepoints, owners most commonly settled dogs to sleep by leaving the dog in a room/area without human company. However, of dogs that did have access to people during the night, more than 86% chose to be around people. Puppies aged 16 weeks were most commonly reported to sleep in a kennel/crate, but dogs aged 12 months most often slept in a dog bed. More research is needed to better understand how the sleep duration and behaviours of dogs change as they age, and how sleep can affect dog health and wellbeing. ABSTRACT: Sleep is a vital behaviour that can reflect an animal’s adaptation to the environment and their welfare. However, a better understanding of normal age-specific sleep patterns is crucial. This study aims to provide population norms and descriptions of sleep-related behaviours for 16-week-old puppies and 12-month-old dogs living in domestic environments. Participants recruited to a longitudinal study answered questions relating to their dogs’ sleep behaviours in surveys issued to them when their dogs reached 16 weeks (n = 2332) and 12 months of age (n = 1091). For the statistical analysis, subpopulations of dogs with data regarding sleep duration at both timepoints were used. Owners of 16-week-old puppies perceived their dogs to sleep longer during the day and over a 24 h period, but for less time during the night than owners of 12-month-old dogs. At both timepoints, dogs were most commonly settled to sleep by being left in a room/area without human company. However, of dogs that had access to people overnight, 86.7% and 86.8% chose to be around people at 16 weeks and 12 months of age, respectively. The most common sleeping place was in a kennel/crate at 16 weeks (49.1%), and a dog bed at 12 months (31.7%). Future research within this longitudinal study will investigate how sleep duration and behaviours change with age and impact on a dog’s health and behaviour.