Castration – Why do they do that?

Rocky Mountain oysters (aka cowboy caviar or bull fries) might in some circles be considered a delicacy. But testicles are not for everyone. Beyond the occasional food eating contest, why do they castrate cattle and pigs?

When managing a herd of cattle, maintaining oversight of the genetics is important. By selecting which bulls are allowed to breed the cows, farmers can positively influence traits in the calves. Traits like weaning weight, muscling, fat, milk production, physical soundness are all closely monitored. By breeding the best quality cattle, farmers produce the best quality meat that will make it to the grocery stores.

In cattle, male calves are castrated through the surgical removal of the testes, an elastrator band, through chemical castration, or through hormonal castration. All have advantages and disadvantages so farmers choose the one that makes the most sense for them and their operation. They try to minimize pain to the animal and increase the chance for a quick and speedy recovery.

There are several reasons that cattle are castrated. Testes produce testosterone. By lowering testosterone levels in male animals, aggressiveness is reduced. From a herd management standpoint less aggression means less fighting and less potential harm to humans. Male animals can also have high muscle pH. This can affect taste negatively. Castration reduces this high muscle pH and can increase the marbling, tenderness, and overall grade quality of the meat. The higher quality meat, the higher market prices the carcass can command.

Just look at the different in body shape and size of the two animals below. On the left is a Black Angus bull (testes intact). On the right is a Black Angus steer that has been castrated.

The bull is much larger and much more heavily muscled. The meat will likely be tougher and not as well marbled. The meat of the steer will more closely resemble the meat from heifers and cows. Consumers crave uniformity in meat and so having a consistent product is one objective of the beef industry.

Pigs are castrated for many of the same reasons as cattle. Meat from male pigs that haven’t been castrated (boars) often suffers from ‘boar taint‘. This smell and taste of pork is caused by excessive testosterone and androstenone and is undesirable. Boars can also be very aggressive toward other animals and toward human farm workers.

Male pigs are castrated at a young age typically surgically using a disinfected surgical knife. After the incision is made and the testes removed, the wound is cleansed. The castrated pig, or barrow, will be less aggressive and have improved meat quality. There are some chemical alternatives to this physical castration. A protein compound that works like an immunization delays the maturity of the animals. This reduces the sex hormones in the animal’s body and reduces the effect of ‘boar taint’.

Castration has been a very common practice in livestock operations. It is one management tool to help ensure quality meat products to consumers. So throw another steak or pork chop on the grill this Labor Day weekend and enjoy!

-Will