Northern View Ranch Sheep

28501 W. Ash Creek Rd
Willcox, AZ 85643
ph: 928-828-9550
fax: 623-321-8188
alt: 602-316-2915
nvrsheep@yahoo.com

Genotyping Sheep Info

Genotyping

You will see references to "QQ", "QR", and "RR" after the names of animals. These two letters refer to their resistance to the disease known as SCRAPIE. The "Q" gene is susceptibility, and the "R" is resistance, Therefore "QQ" animals have no resistance, "QR" animals have some resistance, and "RR" animals are almost completely resistant(The #of "RR " animals that contract scrapie is negligible). ALL Northern View Ranch sheep except Dorpers and White Dorpers, retained or sold will be genotyed "QR" or "RR", this only applies to intact animals not wethers or market lamb ewes.

Genetic Probablility of Offspring

The following tables represent the probability of the genotypes that EACH offspring will have, based on the parents genotypes. Each of the four highlighted squares represents a 25% probability.

Every sheep has one genotpye and two genes that control their suseptablity, they're either "QQ", "RR", or "QR". When they pass on their gentic material, each parent passes on only one of those genes to the offspring, either a "Q" or an "R". So if you were to breed two "RR" animals ALL the offspring will be "RR", and two "QQ" animals will ALL be "QQ" becuase both parents are passing on the same gene.

	Q	Q		R	R
Q	QQ 100%	QQ	R	RR 100%	RR
Q	QQ	QQ	R	RR	RR

If you were to breed an "RR" animal to a "QQ" animal, the resulting offspring will ALL be QR because one parent is passing on an "R" and the other is passing on a "Q".

	Q	Q
R	QR 100%	QR
R	QR	QR

Now say you breed a "QR" ewe to a "RR" ram(doesn't matter if the genotypes are reversed i.e the ram is "QR" and the ewe is "RR"), the ram can only pass on an "R" gene, but EACH of the offspring have a 50% chance of recieving a "Q" gene and 50% chance of an "R" gene from the ewe.

	R	R
Q	QR 50%	QR
R	RR	RR 50%

The same is true of a "QQ" ewe being bred to a "QR" ram, the ewe can only pass on a "Q" gene, but EACH of the offspring have a 50% chance of recieving a "Q" gene and 50% chance of an "R" gene from the ram.

	Q	Q
Q	QQ 50%	QQ
R	QR	QR 50%

If you were to breed a "QR" animal to another "QR" animal you can end up with anything, but the odds are 50% "QR", 25% "QQ", and 25% "RR".

	Q	R
Q	QQ 25%	QR
R	QR50%	RR 25%

Pictures of our new Rams

for the 2011 lamb crop posted soon!!

Last lamb crop for Limo May 2011

Also lambs from a GUNSLINGER Son TUGBOAT

An a SPOT Grandson CHECK MARK

28501 W. Ash Creek Rd
Willcox, AZ 85643
ph: 928-828-9550
fax: 623-321-8188
alt: 602-316-2915
nvrsheep@yahoo.com