| | Why should bull calves be castrated? What are the advantages?
The breeding herd requires much less breeding males than females, and a surplus of males would mean greater competition for breeding and potential risks of inbreeding happening in the herd. On average, only one bull is needed to breed 25 females in a breeding season. Male offspring may be considered inferior with undesirable traits that the producer does not wish to pass on to other cows, or are born to a herd that raises offspring for the purpose of sale for beef. Castrating these males makes them more desirable for beef production and significantly reduces their affinity for aggressiveness and sexual interest towards nearby females.
Steers, because of their ability to be easier and safer to handle than bulls, also grade better. Fewer steers grade as dark cutters (B4) because they are less apt to get stressed, especially right before slaughter. Cattle carcasses that grade as B4 are discounted, reducing market value for that animal. Steers also tend to have more marbling than bulls, which will also increase grading and their market value.
What are the disadvantages of castration?
Even though castration improves carcass quality, daily gains and feed conversion ratios are decreased in steers compared with bulls. Bulls are able to have an average daily gain that is 19 percent greater than steers with only a 3 percent higher average daily feed intake. Use of growth promotants, however have been able to offset these disadvantages to produce steers with rapid growth and efficient feed conversion.
Castration may also result in complications including infection, swelling, bleeding, discomfort and pain. These complications are minimized when castration is done at the youngest age possible, using proper, clean techniques and well-maintained equipment, and through effective vaccinations for tetanus and other Clostridia spp. bacteria.
What is the best age to castrate bulls or bull calves? Why?
Ideally, the earlier castration is done in the calf's life, the quicker it will recover, and the less discomfort and trauma that calf will experience right after the process. Calves can be castrated up to eight months of age, though the older the calf, the greater the stress and risk of bleeding. However, castrating calves when they are less than eight weeks old is recommended; the process is quicker and less stressful for both the producer and the calf, especially when done properly and quickly.
Will castrating bulls after puberty result in better weight gain and feed efficiency than steers castrated earlier?
Studies have shown that castrating bulls after puberty does not allow the advantage intact bulls have over steers with feed efficiency and average daily gains. Instead, steers that have been castrated late have been shown to have a slaughter weight that is equal to or less than those steers castrated before puberty.
The testes produce androgens during puberty for the development of male reproductive organs, external secondary sexual characteristics, and male behaviour. Androgens, together with increased nitrogen retention, promote development of muscular development. However, castrating bulls after puberty will cause these animals to lose weight and have a decrease in ADG, partly due to hormonal withdrawal. Weight loss, a drop in average daily gain and average daily feed intake are also due to discomfort and trauma associated with post-pubertal castration. Also, the loss of testosterone in their system would cause shrinkage of the reproductive organs and musculature in the forequarters. The weight-loss period for these animals can be as long as 4.5 months.
Can bull calves be castrated at weaning?
Bull calves should not be castrated at weaning. Weaning is already a very stressful time for calves, and with the combination of castration and being separated from their dams, will predispose them to stress-related illnesses such as shipping fever. It is highly recommended to castrate calves before weaning.
What castration methods can be used on my young bulls or bull calves?
Two primary methods exist for castrating bulls and bull calves: Bloodless, and Surgical.
Bloodless castration involves "banding" (using elastrator rings) for calves younger than one month of age, using latex bands for older calves, or the Burdizzo method: also for older calves. Elastrator banding cuts off blood supply to both testes causing them to slough off in three weeks or more. It is important that both testes are felt in the scrotum before the band is released, otherwise "belly nuts" will result (testes that are mistakenly pushed up into the abdomen) that will have to be removed surgically when the animal is older. The Burdizzo method crushes the cord and blood vessels that supply each testicle. Crushing causes enough impairment to render the testicles non-functional; they will become shrunken over time.
Surgical castration should be used on calves less than three months old; however, it can also be done on older cattle. Surgical castration in young cattle involves cutting open the bottom of the scrotum large enough to encourage drainage; then the testes are then removed by first pulling until the spermatic cord muscle separate, and the testes removed by scraping, not cutting, the spermatic cord as close to the scrotum edge as possible. Another method of surgical castration is using an emasculator to crush and cut the spermatic cord; this method reduces the amount of blood lost. Disinfecting instruments and cleaning the surgical area beforehand must be done to reduce risk of infection.
Which castration method is best?
There is no clear evidence that either surgical or bloodless castration methods results in better animal performance. However, use of banding in post-pubertal cattle may result in delayed healing above the banding site, and thus may be less safe for these animals than surgical castration. Banding versus surgical method in younger cattle, though, is up to the choice of the producer.
Should something be done about pain when castrating cattle?
Pain associated with castration is a contentious issue, but it depends on what method is done and what age the animal is. Basically, surgical castration causes intense pain that only lasts for a few days, but banding will cause less intense yet more chronic pain that will last for over a month. Pain mitigation may be required for older calves and bulls, but not necessarily for younger calves or calves castrated soon after birth. This is because stress and discomfort associated with castrating is considerably less when the animal is quite young. Research is limited with this issue and currently ongoing. Talk with your veterinarian about pain mitigation with castrating cattle should you have any concerns.
When is the best time to castrate calves?
Bull calves should be castrated as young an age as practical, and certainly before weaning. Animal welfare is improved with improved health, rate of gain at finish and improved carcass quality. It's also ideal to avoid castrating during the fly and insect season.
References:
Bretschneider, G. 2005. Effects of age and method of castration on performance and stress response of beef male cattle: A review. Livestock Production Science. 97:89-100.
Castration - Beef Cattle Science |
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