4 — Colors in Live Stock 



The segregation occurring in the F2 generation into pure 

 dominant, impure dominant and pure recessive explains 

 some of the divergent experiences of stock-breeders. For 

 example, Black Aberdeen-Angus cattle sometimes have 

 red calves; white- faced Herefords color-faced calves; and 

 black French Canadian Cattle calves with a white splash ; 

 but chestnut Suffolk mares always have chestnut foals. 

 The explanation is that the black of the Aberdeen-Angus , 

 and the white face of the Hereford are dominants, while the 

 chestnut of the Suffolk horse is recessive. Inasmuch, how- 

 ever, as all breeds are impure at their origin, impure domin- 

 ants will likely persist as they are indistinguishable from 

 the pure dominants, and recessives will occasionally appear. 

 On the other hand ,when the recessive color is chosen as the 

 type, as chestnut in the Suffolk horse, it is pure and will 

 always breed true to color. ^ 



It may be observed that the laws of inheritance of such 

 unit-characters as size, shape, fertility, vigor, endurance, 

 milk production etc., have not yet been determined. It is 

 likely that in these cases many factors are involved. 



Prof. Wilson of Dublin states that white, black, red, 

 light dun and brown are true-breeding colors in cattle, and 

 that yellow, dun, brindle, blue roan and red roan are hybrids 

 and do not breed true. Of the true-breeding colors "two 

 only behave as dominant and recessive — black being dom- 

 inant to red. The others produce intermediate hybrids" 

 as follows: 



The colors of horses may be arranged in a series — 

 "grey, dun, bay, black, chestnut, in which those coming 

 first are dominant to all coming later, and those coming 

 later recessive to all before them" (.Wilson). 



(1) — The reader should consult "Genetics in Relation to Agricuture" by 

 Babcock and Clausen for a fuller discussion of the coat colors 

 of domesticated animals. 



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