26 CIRCULAR 824, U. S. DEPT. OF AGRICULTURE 
Length of stride at the trot ranged from 7.9 to 12.4 feet with an 
average of 10 feet. It was significantly associated with sire (table 2), 
time required to trot a mile and to cover the 11.35-mile course (table 
5), sex (table 11), general conformation and top line of back (table 17), 
and ease of trot to rider (table 18). Geldings had, on the average, 
the longest stride (10.3 feet); stallions, the shortest (9.1 feet); and 
mares, intermediate (10 feet). Averages for the offspring of different 
sires ranged from 8.8 to 10.6 feet (table 2). However, an analysis of 
the variance between the offspring of different sires within the same 
sex showed that the average difference was not significant. 
Horses with different scores on general conformation differed sig- 
nificantly, though not consistently, in average length of stride. In 
- general, horses with intermediate scores for conformation, as well as 
for top line of back and top line of withers, had the longest stride 
(table 17). 
Action at the walk, which was significantly associated with time 
required to cover the 11.35-mile course, performance at the walk, and 
ease of walk (table 7), and with ease of handling at the trot, was not 
significantly associated with differences between sexes, offspring of the 
various sires, or the progeny of sires within sexes. 
Action at the trot was significantly associated with the sire (table 2), 
time required to cover the 11.35-mile course, performance at the walk 
and trot, and ease of walk and trot to rider (table 7), and differences 
in the dams (table 18). Considerable spread was found in the dis- 
tribution of the offspring from some of the sires (figure 4). This may 
indicate segregation of genetically different types. 
Temperament, which was significantly associated with length of 
stride at the walk and all the riders’ scores except for ease of canter, 
was not significantly associated with differences between sexes or 
between the progeny of sires within sexes. 
Heart girth, which was somewhat associated with length of stride 
at the walk (table 16), was not significantly associated with differences 
between the offspring of the various sires when the effects of sex were 
removed. 
General conformation, which was significantly associated with time 
required to trot a mile (table 10), length of stride at trot (table 17), ease 
of handling at walk (table 18), and sex (table 18), was not associated 
with differences between the offspring of the various sires. The stal- 
lions averaged the highest conformation, mares the next, and geldings 
the lowest. 
Top line of back, which was significantly associated with the time 
required to cover the 11.35-mile course (table 12) and length of stride 
at the trot (table 17), was not significantly associated with differences 
between the offspring of the various sires, although the association 
approached significance. The averages for the different sires ranged 
from 4.3 (medium) for Hudson’s progeny to 7.5 (short, level) for 
Laddie’s progeny. The progeny of Goldfield and Canfield averaged 
medium-+ (6.0 and 6.1, respectively). 
