Saddleback Journal of Biology - Saddleback College

Spring 2010 Biology 3B Paper
supervised by Dr. Harner, DVM, between the ages of
1.5 and 7 years, and weighed between 10kg and
55kg. Humerus length was taken using a measuring
tape by measuring from the point at which the
humerus meets the scapula to the point at which the
humerus meets the ulna. Radius measurements were
taken by measuring from the point where the
humerus and radius meet to the point where the
radius meets the metacarpals.
Dogs had the bottom of their paws dipped in water,
and were trotted at a speed of 2.5 m/s on asphalt (this
speed was approximated at running a distance of 25
meters in 10 seconds) and the distance between wet
pawprints was be measured. A dog’s trot is a twobeat
gait, with the legs moving in diagonal pairs
(front left/hind right and front right/hind left), so
trotting pawprints appear as two prints diagonally
separated by about one or two centimeters, and then
another two prints at an average of 50 centimeters
away. The larger distance (the stride length) was
measured and the mean of three sets was taken. The
mean distance was used in final data and calculations.
Results were obtained using the ANOVA, two-tailed
t-test, and statistical analysis (Excel 2007.)
Results
The results showed that there was a
statistically significant difference between the 3
classifications of dogs studied. Dogs with a humerus
to radius ratio of 0.65-0.89 showed a mean stride
length of 46.7 (±SEM, N=11) and dogs with a
humerus to radius ratio of 1.05-1.30 showed a mean
stride length of 50.70cm (±SEM, N=9). In
comparison, dogs with a humerus to radius ratio of
0.90-1.04 showed a mean stride length of 55.85cm
(±SEM, N=5). This result was significantly different
(ANOVA, p=1.29x10-21, Post Hoc, p