| Guinea Pig Color Breeding Information
First let me state that what follows is not an absolute. Guinea pigs can and do like to surprise you. This is only intended as a guide to color breeding not as the rule. I did not write the original article and do not know the author but have adapted it based on my experiences and I am sharing it as I found it easy to understand and well written.
Breeding solid or self colored guinea pigs to broken colored guinea pigs will haunt your breeding with poor patterns and unexpected mismarks for many generations.
Mixing the Intense (dark-eyed) colors to Dilute (pink-eyed) colors will in most cases result in fading of the primary color and/or darkening of the dilute colors and is not recommended.
To prevent mixing or adding unwanted colors or patterns into your breeding, anytime you use a white animal with another color is is extremely important to know that background colors of the white. Be sure the background colors on the white are compatible with the color you are attempting to achieve.
SELFS:
Selfs are sometimes bred to some of the marked varieties such as the Roans and Dalmatian. Himalayans may be bred to blacks. Brindles and Tortoiseshells can be bred to self black or self red.
Beige: You can breed beige to beige of course but you can also breed to white and chocolate. You may get a darker beige or a lighter chocolate when breeding to chocolate. When breeding to white look closely at the pedigree first.
Black: This color can be bred to quite a few other color varieties. You can breed black to either silver or golden aqoutis and solids. You can also breed (of course) to other blacks.
Chocolate: You can breed this color to chocolate, beige, and to red.
Red: You can breed to red or chocolate.
White: You can breed to white, beige or cream. When breeding any white look closely at the pedigree first. You will find that some whites carry other colors or patterns that may not be compatible with your breeding goal.
Cream: You can breed to white or cream.
Red-Eyed Orange: You can breed to red-eyed orange or white. If breeding to white be careful of the eye color of the whites. A white can be dark -eyed and a dark eye will dominate giving you a poor red rather than a red-eyed orange.
MARKED VARIETIES:
Roan: One parent must be roan the other parent can be almost any of the other self or solid varieties as long as white or white patching is not included as it can cause unwanted patching. Breeding Roan to Roan can carry a recessive gene which will produce lethal whites which can have any or all of the following genetic defects: blindness, deafness or misshaped teeth. It is advised that roans be bred to a self or solid color.
Dalmatian: Since breeding Dalmatian to Dalmatian tends to have the same genetic problem as breeding roan to roan the recommended procedure to breed them is a "dominant modifier to a self". I recommend talking with breeders more familiar with roans and dalmatians before getting into breeding them yourself.
Tortoise Shell (TS): Although some breed to tortoise shell and white I have found that by adding the white to the gene pool it is very hard to breed it back out and small patches of white keep showing up. The best breeding is to another tortoise shell with good color. If this is not possible then breeding to a good red or a good black can be done but may cause some problems in distribution of patches.
Tortoise Shell and White (TSW): Breeding to other TSW’s is best but this is a broken color and options do include breeding to other intense broken colors.
Himalayan: This variety does not cross well with other varieties. It is at all times best to breed to other Himalayans. If you do breed to blacks any blacks that are produced from this may not be good breeders as their color is diluted.
BROKEN COLORS:
There are two classes of broken color: (1) Intense or primary and (2) pastel. Mixing the two will in most cases result in fading of the primary color and is not recommended.
SOLIDS:
Brindles: Brindles are best bred to another brindle, a self red, a self black or a tri roan. If breeding to a self color it is helpful to use one from a roan background to encourage an even intermixing of the red and black. You can also use red or black roans.
AGOUTIS:
With agoutis it is not recommended that golden or silver agouti be bred to dilute agouti as it will result in fading.
This guide is offered as suggested breeding options and not "as the only way to do it".
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