Breeding and Pregnancy

Breeding

How do you select the right animals to breed together? That has a lot to do with the animal’s strenghts and weaknesses, coloring, weight, shape, and conformation. When selecting to put animals together, its best to consult another breeder until you are starting to understand how animals are judged and what characteristics make a good breeder. Also ensuring you are not pairing lethal animals together is also important. The lethal genes are white, and TOV. As a rule, almost all breeders to not breed white animals to another white animal, and very few breed TOV animals to TOV animals. The MCBA states animals under 600 grams as not strong candidates for breeding (this is especially true for females) but its good to know that even the really large may not breed due to excess fat. Remember that the animal’s lineage is important in deciding the right pair. If you are more interested in this subject, please feel free to contact me, or visit the MCBA website.

Pedigrees and Pet Store Chins

It should go without saying that animals without pedigrees, purchased from a pet store, or sold to someone as PET ONLY are not meant to be bred. These are animals that have been culled from breeding for one reason or another by someone who knows about the lineage.

The Lethal Factor

“There are two color genes in chinchillas that are referred to as “lethal genes”. These are the Velvet (TOV) gene and the White gene. Neither of these genes can exist in the homozygous state, meaning a gene pair of Velvet + Velvet or White + White would not develop beyond the early embryonic (zygote) stage as it is not viable. It has been said that when this embryo dies and is reabsorbed it can cause blockage of that uterine horn (chinchillas have two horns to their uterus that branch out from the cervix). I doubt this is the case as a zygote is microscopic, but the resorption could cause other problems. The result of breeding two animals with lethal genes may just be smaller litters, but it is probably best to avoid such a pairing. Any two animals carrying the Velvet gene should not be bred together (i.e.. Black Velvet + Brown Velvet, TOV White + TOV Violet, etc.) and any two animals carrying the White gene should not be bred together (i.e.. White Mosaic + Tan and White, Ebony and White + TOV White, etc.). Any of these colors can, although, be bred with any other colors.” -Quoted from Amy at ChinBin in Oregon. Thanks Amy!

Breeding Age

Females should not be bred until they are at least 10-12 months old depending on weight and size. Some females may not be large enough to go into breeding until 14-16 months of age. Males can technically enter breeding as young as 4 months old, but you don’t know the conformation and strengths of the males at that time. 8-12 months is the normal recommended breeding age in males.

Time Length of Pregnancy

Pregnancy lasts an average of 111 days, with the acceptable range being 103-120 days.

Weight Gain

Weight gain is a normal method for monitoring the progression of the pregnancy. Normal pregnancy weight can be as low as 100 grams, to as high as 350 grams. This does not always tell you how many kits the mother is going to have. You will see about 25-30 grams of weight being gained each month for the first few months, then the last month to month and half, a substantial weight gain. The weight gain often slows a week or two before birth, and sometimes the mother may lose some weight as well.

Keeping chins together?

If you are breeding in pairs or trios, you can often keep the pregnant female with the male for most of the pregnancy. If you know the exact date of conception (or within a few days), you can know that by day 100 or so, to remove the male if in a pair, or seperate out the female if in a group. SOME females do fine raising their kits with other females in the cage, but this doesn’t mean all females will do well. Some moms who do fine raising kits with other females in the past doesn’t mean it will continue. With first time moms its best to remove the dad or remove the other chins and let her raise the kits without distraction. In some cases, the chins can be put back in with mom, but that must be on a “as is” basis, and doesn’t always work. Many of my breeding friends will pull the mother and let her raise the kits alone, because repairing doesn’t always work as fast as we would like, and sometimes doesn’t work at all.

The end of the pregnancy

During the last few weeks of the pregnancy, you may notice the kits kicking in the belly, mom laying on her side, and often down more on the shavings than normal. This is her preparing for labor, and just plain tired. She may aggravated easily, and will not want to be handled. This is normal, so the less handling, the better.

This is Camille sleeping on her back, hanging out of her hammock, extremely pregnant. She does this for hours on end! They find unique ways of getting comfy!