If you’re a beginning goat farmer and you’re trying to save on money, it might be a good idea to let the litter of goat siblings just breed with each other. But what are the risks, if any, and should it be done at all?
There are a lot of unintended negative consequences that result from inbreeding with goats and every other animal. However, when used correctly, (never with a brother and sister) it can help to enhance the good traits of the herd.
Just like anything else, this can be a good tool when utilized properly. But if you’re new to goat farming, it might be best to avoid this dicey breeding strategy altogether due to all the horrible effects of inbreeding in organisms of all shapes and sizes.
Inbreeding and DNA
If you ever took biology in high school, then you’re probably familiar with the Punnett Square. It’s a simple concept used to demonstrate how dominant and recessive genes work, usually drawn out in four connected squares. Long story short, each person has two copies of each gene, but when they have children, they only give one copy of their gene to the child.
When the child gets the two copies of those genes, their genetic traits will all change based on how many dominant or recessive genes they got. If even one parent gave a dominant gene, then the child will express the dominant trait. In the image above, two flowers breed, each with one dominant and one recessive gene. In the end results, the recessive gene is only expressed in one of their offspring.
But when inbreeding happens, very tightly closed gene pools are reused over and over again, and this can cause many issues. The main reason it causes issues is that it gives a higher chance of those recessive genes to be expressed–and sometimes those recessive genes express genetic diseases.
Lack of diversity in genetics, for whatever reason, causes a multitude of problems since the cells constantly copying these DNA strands are getting “sloppy.” The same gene pool makes them start to mutate the genes as they replicate strands of DNA. Inbreeding doesn’t just bring out the hidden traits within a genetic pool, but it has a nasty tendency to create new problems out of thin air.
Inbreeding in Humans and Animals
There have been many known cases of nasty inbreeding from human history, the most notorious being European royalty.
This is no surprise. Royalty was so concerned with purity and staying away from the “lower” classes that they failed to realize the many benefits of mingling with those outside of their station. Not only would it have given them a new perspective on life (and hopefully knocked them down a few pegs), but it also would’ve brought in some much-needed genetic diversity into their inbred lines.
But they never mingled with the common folk, and plenty of them suffered for it. Richard III, Charles II, and “Mad King George” all had to deal with the negative consequences of their parent’s horrible decision-making. Shakespeare called Richard III “cheated of feature by dissembling nature” due to Richard’s curved spine and strange appearance. When Richard III’s bones were finally dug up in a Leicester Cathedral, the skeleton “had several unusual physical features, most notably scoliosis, a severe curvature of the back.” Charles II of Spain had a disfigured jaw, making it impossible to eat, and he was unable to walk until he was eight years old. And King George III lost his mind (gaining his aforementioned nickname) due to a hereditary disease known as porphyria.
Humans aren’t the only ones to suffer from the nasty side effects of inbreeding. Have you ever wondered why dogs have so many breeds when they’re all part of the same species?
It’s because of something called “selective breeding.” It started because people began noticing certain traits some dogs had, and they wanted to increase those traits, whether it was black spots or an ability to herd sheep. This is a great idea on paper, but over time, the good traits weren’t the only ones being enhanced. The bad traits were as well, and purebred dogs today still suffer from this practice.
Pugs got the short end of the stick. They’re the most inbred dogs of all time, and because of it, every single pug born today has more problems than they can handle. For instance, their faces were bred to be as flat and cute as possible, but because of that, now it’s nearly impossible for them to breathe.
Bigger dogs were bred together–and now it’s taken a serious toll on their life span. Great Danes usually have to deal with hip dysplasia and bloating, and they rarely, if ever, live to ten years old. Pit Bulls were bred for their aggression, and they have the potential to go crazy because of it. Even German Shepherds can inherit a spinal cord disease that can cause paralysis.
Linebreeding
Despite all of the ways that things can go wrong genetically from inbreeding, there is still a benefit to using it with farming. This version of inbreeding, called linebreeding, started for the same reason selective breeding started. If a liter has good qualities, the best way to “farm” that quality is to breed that liter with other animals that also have that trait.
However, the best way to build up a good group of goats right away is NOT to start with this tactic. Linebreeding is good to use later when you’ve already established a healthy herd of goats, but up until that point, do your best to introduce diversity and new genetic pools into the equation.
Something you should never, ever do is breed two direct siblings with one another. It should be obvious why, besides the basic fact that it’s just messed up. Siblings can share up to 50% of the same DNA. The gene pool will be really small, so the potential good traits AND potential problems will only multiply with their offspring.
Once it comes time to breed goats, instead of breeding siblings, experienced goat farmers recommend breeding relatives that are further apart, such as uncle and nieces, grandfathers and granddaughters, and in some cases (if there’s no other option) father and daughters. But don’t worry; your goats aren’t Oedipus, and the world won’t spontaneously combust from their linebreeding. Despite all the negative side effects mentioned, it can be beneficial if you are careful to pick a few good bucks with good traits that you want to see passed on to future generations in your herd.