Coat Colour

Coat Colour in Angus

Angus cattle in Australia predominantly come in two colours, Red and Black. This colour variation is caused by a single gene for which a commercial DNA test is available. Every animal carries two copies (alleles) of each gene, one of which is inherited from the animal’s sire and one is inherited from the dam. Of the two alleles present in each individual, the one that is passed on to progeny is randomly selected (irrelevant if both alleles the same). These inheritance patterns can be observed in the punnet square diagrams in the examples at the bottom of this article.

The red coat colour is what is termed recessive. This means that a Red individual must have inherited the Red coat allele (e) from both parents. However, if one of the parents passes on the black allele (E) to the progeny, the progeny will be black regardless of whether the 2nd allele is black (E) or red (e). Animals are referred to as carriers, or heterozygous, if they are black but carry the Red allele.

Coat Colour Genotypes

A third coat colour allele also exists (Wild Type) but this is rarely observed and does not alter coat colour if either the Red (e) or Black (E) allele is present.

The following are descriptions of the progeny you would expect on average if Red or Red Carrier Angus bulls are used in your herd. The exact proportions may vary in smaller populations.

More detail on the genetics of coat colour in cattle can be found: http://sbts.une.edu.au/media/1075/coatcolour.pdf

Article courtesy of SBTS & TBTS

Red Bull

Red Cow e e e ee (red) ee (red) e ee (red) ee (red)

Black Cow Red Carrier

E e

Red Bull e Ee (black but red carrier) ee (red) e Ee (black but red carrier) ee (red)

Homozygous Black Cow

E E

Red Bull e Ee (black but red carrier) e Ee (black but red carrier)

Black Bull Red Carrier

Ee (black but red carrier)

Ee (black but red carrier)

Red Cow e e

E Ee (black but red carrier)

Ee (black but red carrier) e ee (red) ee (red)

Black Cow Red Carrier

E e Black Bull Red Carrier

E EE (black) Ee (black but red carrier) e Ee (black but red carrier) ee (red)

Homozygous Black Cow E E

Black Bull Red Carrier

100% Red Progeny. Red Bull (ee) x Red Cow (ee) = 100% Red progeny (ee)

E EE (black) EE (black) e Ee (black but red carrier)

Ee (black but red carrier)

50% Red & 50% Black Progeny. Red Bull (ee) x Heterozygous Black/Red Carrier Cow (Ee)

= 50% Red (ee) and 50% Black progeny. All black progeny will carry the Red allele (Ee).

100% Black Progeny. Red Bull (ee) x Homozygous Black Cow (EE) = 100% black progeny All black progeny carry the Red allele (Ee).

50% Red & 50% Black Progeny. Red Carrier/Heterozygous Black Bull (Ee) x Red Cow (ee) = 50% Red (ee) and 50% Black progeny. All black progeny will carry the Red allele (Ee).

25% Red & 75% Black Progeny. Red Carrier/Heterozygous Black Bull (Ee) x Heterozygous Black/Red Carrier Cow (Ee) = 25% Red (ee) and 75% Black progeny. 2/3rds of the black progeny (50% of all progeny) with carry the Red allele (Ee) and the remainder (25% of all progeny) will be homozygous black (EE).

100% Black Progeny.

Red Carrier/Heterozygous Black Bull (Ee) x Homozygous Black Cow (EE)

= All progeny will be black. 50% will carry the Red allele (Ee) and 50% will not (EE).