McCann: Sorrel Color in Horses yi! 
MATINGS OF VARIOUS COLORS AND COLOR OF OFFSPRING 
Sorrel x Sorrel 
Sorrel Bay Brown Chestnut Black Roan 
61 1 0 0 0 1 
Chestnut x Chestnut 
5 0 0 13 0 0 
Sorrel x Chestnut 
23 3 11 ; 0 1 
Sorrel x Bay 
78 95 10 6 
Sorrel x Black 
9 8 0 6 1 
Chestnut x Black 
1 2 1 1 1 1 
Chestnut x Bay 
ae 48 0 fl 0 
recorded as an offspring in the sorrel 
by sorrel cross is due to a mistake in 
recording, or that one of the parents was 
a roan animal with a very few white 
hairs showing, which is a case of 
incomplete dominance. Occasionally, 
animals are seen which from a distance 
appear to be sorrel, chestnut or bay in 
color, but upon close observation a few 
white hairs are apparent in the coat. 
It has been found by other investigators 
that there are a small number of mis- 
takes in the stud books as regards coat 
colors, because color is considered a 
matter of minor importance by a great 
many breeders. 
SORRELS ARE ABUNDANT 
The chestnut by chestnut matings, 
while few in number, serve to demon- 
strate that sorrel is recessive to chestnut. 
In order to conform exactly to Mendel’s 
Law the offspring should be in the 
proportion of three chestnuts to one 
sorrel, and they do approach this 
proportion rather closely, being thirteen 
to five respectively. There is a pre- 
dominance of sorrels as compared to 
chestnut, in the Belgian breed studied, 
and it would therefore be expected that 
a larger number of the chestnut animals 
would be heterozygous for sorrel, than 
if these two colors were present in 
equal numbers. This is more clearly 
shown in the chestnut by sorrel matings. 
Again considering the matter theoreti- 
cally, if the two colors were present in 
3 ‘‘Why is a Horse Bay?” 
equal numbers, there should be fewer 
sorrels than chestnuts resulting from 
this cross, but there are twenty-three 
sorrels to eleven chestnuts. The same 
thing is brought out in the sorrel by bay 
matings. The sorrels and bays are 
present in about the proper proportion, 
but theoretically, there should be a 
larger number of chestnuts. 
The bay by chestnut matings also 
substantiate the fact that sorrel is 
recessive to chestnut. If such were 
not the case the number of sorrels from 
this cross would be very small as com- 
pared to the others, but the result is 
twenty-two sorrels, forty-eight bays, 
eight chestnuts and one black. 
The sorrel by black matings give a 
result similar to the chestnut by black 
matings. The former gives nine sorrels, 
eight bays, one roan, one chestnut and 
six blacks, and the latter, one sorrel, 
two bays, one brown, one roan, one 
chestnut and one black, showing that 
sorrel and chestnut are qualitatively 
alike. The occurrence of bay offspring 
from these matings is explained by 
Prof. E. N. Wentworth? in the following 
way: 
“The bay coat results from the pres- 
ence of two pigments in the hair 
tubules, viz., red, and black. There is 
a factor associated with the red pigment 
which restricts the appearance of the 
black pigment to certain parts of the 
body, as the mane, tail, legs and around 
the eyes. In the case of sorrels and 
The Horseman, November 10, 1914. 
