Buckley, L. A., Whalley, C. 2019. The use of synthetic grass as a novel substrate within veterinary practice canine inpatient elimination enclosures. Journal of Veterinary Behavior 34, 42-51.

Dogs form toileting preferences that may influence canine elimination behaviors. This study aimed to assess the effect of providing a novel substrate (synthetic grass) on indices of canine willingness to eliminate, plus associated behavioral parameters. At a veterinary hospital, an ad hoc sample of dogs (irrespective of age, sex, neuter, or fluid therapy status) were randomly allocated (based on day) to one of two treatment groups and given opportunities to eliminate off-leash (between 08:00 and 15:00 h) in an outdoor enclosure every two hours until urination occurred (or other factors prevented the dog being taken to the elimination enclosure) or data collection ended for that day. The two treatment groups were as follows: (1) synthetic grass (n = 86), and (2) concrete (n = 106), with the treatment variable being the substrate the dogs experienced in the elimination enclosure. The proportion (95% confidence interval) of dogs urinating on the first outdoors elimination opportunity was 0.77 (0.66-0.85) for synthetic grass and 0.74 (0.64-0.82) for concrete. The proportion (confidence interval) of dogs that defecated at least once was 0.19 (0.11-0.28) for synthetic grass and 0.19 (0.12-0.28) for concrete. No significant effect of substrate was identified on proportion of dogs that urinated either on the first trip to the elimination enclosure or at least once during hospitalization, proportion of dogs that defecated at least once, latency to urinate or defecate, duration of urination, locomotion, sniffing behavior, or position adopted when urinating or defecating. Locomotion predicted urination, with dogs that urinated being more active (P < 0.001). Sexually dimorphic effects on urination (but not defecation) were observed, with males quicker to start urinating (P < 0.001), more frequently (P = 0.048), and for a shorter duration (P = 0.004) than females. Finally, entire dogs of both sexes performed more sniffing behavior than neutered dogs (P = 0.008). It is concluded that synthetic grass does not impact on canine willingness to eliminate but further research should quantify any effect of synthetic grass on disease transmission and hygiene before adopting its use more widely in veterinary practice.