Introduction

• Most breeds of beef cattle have a color pattern that is characteristic for that breed. For example, all Hereford cattle have a red body color with a white face, and Black Angus are black. Some breeds also have colors which are unpredictable, for example, spotting, brindling or solid colors in Longhorn.

• Knowledge of the genetic aspects of hair color allows prediction of the color pattern to expect among calves when crossing breeds. The predictions discussed in this fact sheet give only the major expected colors.

Inheritance of Color All cattle have a basic color of black, red or white. Since all cattle have two genes for basic color, this makes six possible genetic combinations (Table 2). Each parent will contribute one gene to the offspring.

The gene for black (Rb) is dominant to the gene for red (R). Cattle with one gene for black and one gene for red will be black. There is incomplete dominance between the gene for black (Rb) and the gene for white (r). Therefore, an individual with one gene for black and one gene for white will be black-roan. There is also incomplete dominance between the gene for red (R) and the gene for white (r), producing the red-roan when these two genes are present. An individual with two genes for white (r) will be white.

Another set of genes determines if color is diluted or not diluted. The gene for dilution is dominant to the gene for nondilution. An animal that has one gene for dilution and one for nondilution will have a diluted color. An animal with two genes for dilution will be diluted and an animal with two genes for nondilution will not be diluted. The dilution gene causes black to be diluted to gray and red to yellow. Diluted white will still be white. Since many more genes can be involved, sets of genes involving color and dilution are only a small part of the overall inheritance of color. There are several other sets of genes that will modify color. There are also several sets of genes that determine color pattern such as the white face, solid color or spotted.

Embryo Transfer Process

Why Embryo Transfer?

More offspring from valuable animals. (Normally get 8-10 offspring from a cow).

Different sires can be used.$$$$

Why Clone a Cow?                                                              •You transmit 100% of the genetics eliminating costly trial and error breeding. •You can increase and assure the supply of semen and embryos. •You preserve desired genetic traits from old, diseased or dead animals. •You can re-create cows and bulls without the original’s reproductive deficiencies. •You have a new cutting edge breeding management option. •You can eliminate some diseases. •You can eliminate titres caused by vaccinations. •You can create a bull from a high performing steer. •You can have a uniform herd that enables production and management to be improved. •You can supply proven bulls for natural breeding.

Enucleation

Chromosomes of each egg are drawn into a needle. A pipette holds the egg still.

                                                   

After Enucleation

Chromosomes are removed, all that remains inside the zona pellucida is cytoplasm.

                                                   

Transfer

A skin cell, or fibroblast, from the animal to be cloned is transferred underneath the zona pellucida, where it remains separate from the egg cytoplasm.

                                    

Fusion

Each unit is exposed to an electric shock that fuses the skin cell with the egg cytoplasm. The skin cell’s nucleus, with its genes, enters the egg cytoplasm. Within a few hours the embryo begins to divide.

                                    

Embryo

Seven days later the cloned embryo is ready for transfer into a recipient cow.

Shoremar S Alicia ET

                                                               

Alicia clone - March 2003

SUMMARY• Genetics are very fined tuned in the

animal world.• Animals can reproduce multiple offspring

(embryo transfer) by different sires or they can be,

• Cloned – exact duplicate DNA –• Next step – take a hair follicle to determine

what genetic code the animal carries – such as genetic abnormalities or high

production