Anonymous said to @ask-drferox : Is double muscling bad? When I had my animal ag class, I was under the impression that it's a painful condition and makes birth difficult or impossible. But the only source I can find on the pain part is from PETA. The reason I ask is because it's one of the things that confounds me about US animal ag - it's not illegal to breed these animals on purpose, you'll just get disqualified in shows. But are they actually fine?
So fun fact: The ‘double muscling’ trait, caused by myostatin mutations, also occurs in humans and there have been a couple of case studies. And those case studies do not report being in pain, so I assume it’s generally not a painful condition, even if it looks like a jolly awkward one.
Animals, including humans, with a single copy of the gene often have larger muscles than those without the mutation, so it’s no surprise that it’s accidentally selected for both in human athletes and meat producing animals. Having a single copy of the gene is advantageous for many producers.
It can have affects on the heart, but not always, and if you have a mother with double muscling (muscles are really more like 30-60% bigger than normal), the muscles inside her birth canal are also larger than normal, making the canal smaller than normal, and the muscles of the neonate are larger as well. So a larger neonate through a smaller canal presents significant difficulties.
So as far as I can tell, double muscling isn’t painful in and of itself, and I really think the humans with this condition would have mentioned it if they were in pain. PETA isn’t exactly something I’d consider a reliable source.
