Meeting Abstract
Tetrapod mammals must distribute their weight between fore and hind legs when standing. The proportion of weight by each couplet can vary with species. An elephant carries 55% of its weight on its fore legs, but a monkey has only 44%. There has been no systematic study of weight distribution to determine if the proportion of supported weight on the fore and hind limbs is dependent on body size. Over a four year period, 595 dogs from 123 breeds ranging in size from Chihuahua to Saint Bernard were measured at the Kennel Club of Philadelphia’s National Dog Show. Each dog was weighed on a digital scale while standing in a show position alternating fore leg and hind leg support. The overall mean proportion of weight on the fore legs to the total weight was 60.4+4.8% (range: 40.3-78.3) with a fore leg to hind leg ratio of approximately 60/40. When separated into AKC categories, only the working group (e.g., Newfoundland, Rottweiler) was significantly above the 60.4% mean. Using the genetic groups by Parker et al. (2017), dogs with large heads were significantly greater than the mean (e.g., bulldog, mastiff), while herders and coursers (e.g., sight hounds) were lower. The genetic groups sorted by von Holdt et al. (2010) indicated that the group containing only retrievers, mastiff-like dogs, and small terriers were significantly greater than the mean. Using AKC-related categories from von Holdt, mastiff-like dogs were significant greater and sight hounds were lower than the mean proportion of weight supported by the fore limbs. The weight of the head, chest, and musculature for propulsion and braking could explain the greater weight supported by the fore limbs. Despite differences in morphology and size, dogs generally display a consistent differential between fore leg and hind leg support.
