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NW Iowa | I've had black bull and a black cow, throw calf with reddish hair.
The two main alleles (or alternative forms) for the melanocartin 1 receptor gene are Black (ED) or, Red (e), while another allele, Wild Type (E+) is also present in a very small percentage of animals, including Angus cattle.
Each animal inherits two alleles for coat colour, one from each parent, with the Black allele being dominant over both the Red and Wild Type alleles. An animal can consequently be phenotypically, or visually Black but still carry one copy of either the Red or Wild Type allele, which can then be inherited and expressed by progeny. The Wild Type allele (E+) is considered to be neutral and can produce either a red or black coat colour depending on its interaction with other genes. The Red allele (e) is recessive and an animal must carry two copies of the Red allele to have red coat colour.
Because animals inherit two alleles for the base coat colour, it is possible that their phenotype, or visual appearance, does not reflect their underlying genotype. For example a phenotypically black animal may be either “homozygous” Black, meaning they have two copies of the Black allele (ie. ED ED), or “heterozygous” Black, meaning they have one copy of the Black allele and one copy of either the red or wild type allele (i.e. ED e or ED E+).
Consider the four mating combinations shown in Figure 1 where only phenotypically black sires are used in a breeding program.
In the first scenario, homozygous black dams (ED ED) are joined to a homozygous black sire (ED ED) with 100pc of the resulting offspring being homozygous black (ED ED).
In the second scenario, heterozygous black dams carrying the Red allele (ED e), are joined to a homozygous black sire (ED ED). The resulting offspring will all be phenotypically black, but 50pc will be heterozygous (ED e) and will carry one copy of the Red allele.
In the third scenario, heterozygous dams (ED e) are joined to a heterozygous sire (ED e), with 25% of the resulting offspring being homozygous black (ED ED), 50pc being heterozygous black (ED e) and 25pc being homozygous red (e e).
In the final scenario, homozygous red dams are joined to a heterozygous black sire. The resulting offspring will be 50pc heterozygous black carriers and carrying one copy of the Red allele, while the remaining 50% would be homozygous red.
The above scenarios not only apply to straight-bred Angus breeding programs, but also to crossbreeding programs where Angus animals may be joined to animals from another breed. For example, if a heterozygous Black Angus sire is joined to Hereford cows, who are homozygous red, 50pc of progeny would be black Baldies, while 50pc would be red Baldies, as per the final scenario.
Edit- In short it is possible the sire and dam to have half the recessive gene and throw each side into the calf
Mating: Parents that are heterozygous have the same 50% chance of passing on the dominant allele as they do the recessive. So, when mating a heterozygous black sire with a heterozygous black dam, there is a 25% chance the progeny will be homozygous dominant, a 50% chance the progeny will be heterozygous, and a 25% chance that the progeny will be homozygous recessive.
Edited by Massey1155 3/8/2026 20:02
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Mystery calf
