Saturday, February 16, 2008

Blazing Along

We come to the Blaze gene. The Blaze gene, Bl, is incompletely dominant, and is common in the Simmental breed.

BlBl animals generally have a large blaze to a white face. Unlike the Sh pattern, they won't have the other associated white areas. BlBl animals with the ss trait for recessive spotting can look a lot like Sh animals.

Blbl animals have less white, usually a blaze, or even as small as a star or a snip.

Here are 2 Blbl animals. As you can see, the black has a full blaze, and the red only has a star and a snip.

Another thing to remember, is that the ss (recessive spots) gene can give very similar results to the Blbl or BlBl.

Here is a calf that very much looks like BlBl or Blbl. However, as both her parents were solid colored, one can presume that they were both Ss blbl in genetic makeup. They both passed on the s gene, to make her ss blbll

Another calf, his parents were ss blbl and Ss blbl. He ended up ss blbl.

This heifer calf is out of 2 Ss blbl parents. Again both parents passed on the s gene, to make the calf ss blbl. This time the calf has only a small amount of white on the head

Brockling, A Mottling of the Facts

The brockling gene Bc is what causes the brockle or mottled faces and legs we often see when we cross Herefords with Angus. There are many breeds that carry this gene, although most spotted breeds, such as Hereford for the most part do not carry it. Normande cattle are one of a few spotted breeds where Bc is common. Bc is dominant, and all it takes is one copy for the trait to be expressed. The amount of brockling is not increased when there are 2 genes present rather than just 1. The Bc affects all white patterns by putting darker colored areas within the white areas, usually on the legs and face. ss animals that carry this gene will often be spotted as normal, but where white is present on their legs they will be mottled.

BcBc and Bcbc animals will express broken patches of color within white spots. They may tie into the colored areas on the animal, or they may be completely separate. If one copy of Bc is present you will see brockling.

This animals is BcBc, she exhibits more color than white, but that is not always the case.

These 3 are all Bcbc animals. The goggles on the last one are more likely due to the Bc gene than any other.

This animal is also Bcbc, but she exhibits the mottling on her legs also

bcbc animals however will not express the mottling. There are other genes which are thought to cause the goggle eyes in the Hereford and Simmental breeds, so it is possible for a bcbc animal to express similar marking and still be Bc free. There is also thought to be a separate gene that causes the freckle effect sometimes seen within the Hereford breed.

These 3 exhibit the goggle eyes, and are more than likely not due to the Bc gene. As you can see, other than their eyes, they have no other brockling type markings.

Color Sided

Color sided is a common coloration in the Longhorn breed. White Park cattle also exhibit this coloration. Color sided is represented by Cs. Cs is also a incompletely dominant trait. The Homozygous animals will exhibit more than their Heterozygous mates.

CsCs animals are will exhibit a white body, with dark points. The ears, muzzle and lower legs or around the hooves.

Cscs animals however show a varying pattern. Often they will have a white dorsal stripe and white belly with color extending from the head, along the neck and often tapering off as it moves back to the hips. These animals may resemble SpSp animals. The color will often roan or turn splotchy around the edges of the pattern. Animals that carry the Rr and Cscs genes, often will result in an pattern that is very similar to the CsCs individuals.

The cow here exhibits the Cscs pattern, however as you can see she did not pass the Cs on to her calf which exhibits cscs.

and, here is her next calf which she passed the gene onto it is Cscs

cscs animals are again solid colored.

Dilution, An Enlightening Experience

Dilution is the lightening effect we see within the Charolais, Simmental (and some other breeds). There are 2 different genes covering these lightening effects. They are Dc and Db. Dc is mainly seen in the Charolais breed, and in fact Charolais cattle are generally Homozygous for this gene.Db is commonly seen in the Simmental, Highland and Gelbveih.

DcDc animals tend to be white in color. The base color is still there, but it is removed by the Dc gene. This gene works similarly to the roan gene.

Dcdc animals tend to vary in color, from very light to quite dark. But, you can usually see the color to them. Black based Dcdc animals will be gray and red based Dcdc animals will be tan in color.

This animal is ee, ss, Rr and Dcdc. She is Red base, recessive spots, roan and diluted.

This animal is Ee, ShS and Dcdc. Black base, Hereford marked and diluted. Notice she is a lot lighter than the 1st cow, but still dark enough that you can see the white face.

The rear calf is also a Dcdc calf, where as the leading 3 are dcdc, that is not diluted.

DbDb animals on the other hand tend to be light in color, but not white. They will be light tan and silver gray.

Dbdb animals will be darker in color than there homozygous counterparts. Dark gray for the black based animals, and light to golden red for the red based animals.

Here is a good example of a Dbdb animal. Notice she has a more goldeny or orangey tint to her coat. Bred black she may throw grey and bred red she may throw a light red.

dcdc and dbdb animals of course are not carriers of the dilution genes, and will be normally colored, black or red.

Roan, a Mixture......

Roan is a gene that is co-dominant, which means that traits are equally expressed. That is that you will see both coloured and white hairs mixed.

It is on a different locus than the spots gene, and can result in totally white, roan coloured or solid coloured animals. It is represented by R or r.R is roan, r is solid.

RR animals are Homozygous for the roan gene. These animals will be white with the exclusion of some coloured hair inside their or around the ears. These animals can only pass on the roan gene, every single calf they have will either be roan, or white, depending on what genes the animal they are bred with/to pass on.

Rr animals are Heterozygous for the roan gene. These animals will be roan. The amount of roaning on the animal can vary a lot. Some will only have a bit of roaning on the tail, face, hocks or brisket. Some will be mostly white with a bit of colour thrown in hear and there. You can have Blue Roans, Red Roans, Tan Roan, Grey Roan and so on. It all depends on the Base colour of the animal. You can have spotted roans, or white faced roans if the animal also carries one of the spotted genes.

The above 3 animals are all Rr. 1/2 of the calves they produce should be roan when bred to solid coloured animals. Notice the difference in the amount of roaning.

This animal is Ee, ShS and Rr. So she is black base colour (red carrier), Hereford marked and Roan in color.
This guy is ee, ss and Rr. So Red in colour, spotted (recessive gene) and roan.

rr is homozygous for solid colour. These animals will be solid coloured, and cannot pass the roan gene on.