Common methods used to castrate bulls
Common physical methods of castration include surgical removal of the testes or stopping the blood flow to the testes by applying an elastrator band or using a Burdizzo tool.
Research from online publication, www.beefresearch.ca states that banding at two months of age makes it less acute, immediate pain than surgical castration, however, banding at four months causes more chronic pain.
Immunocastration uses a strategic injection of hormone suppressants and requires repeated injections to remain effective.
The methods include:
- Surgical castration
Surgical castration involves making an incision into the scrotum followed by the physical extraction of both testes.
Physical removal is also used when necessary at the feedlot, where intact males are typically six to 12 months of age.
- Elastrator banding
Elastrator banding involves using a specialized tool to place a purpose-designed rubber ring or latex band around the scrotum, between the testicles and the abdomen.
This interferes with the blood supply to the testis, causing the testis and the scrotum to slough off three to six weeks later.
The rubber ring technique is typically performed on at birth or within a few days of birth. This method is relatively rapid in young animals and has a low failure rate.
Older animals may be banded using latex bands, however, they may have an increased risk of tetanus. Farmers should consult their veterinarians about providing additional vaccination protection.
A Burdizzo is a specially designed clamp that is used to physically crush the testicular cord through the scrotal skin.
This trauma disrupts the testicular blood supply, causing the testes to die.
With this technique, the scrotum remains intact, the testes eventually shrink down, and the animal becomes sterile.
This technique is becoming less common in the cattle industry.
Compared to surgical castration, this method takes longer and has a higher failure rate of up to 35 percent, particularly with old or poorly maintained equipment.
- Chemical Methods
Chemical castration includes injection of sclerosing or toxic agents such as lactic acid into the testicular parenchyma to cause irreparable damage and loss of function.
Chemical castration requires additional procedural time and technical skill, and almost twice the healing time compared with surgical castration.
- Hormonal Methods
Hormonal castration (immunocastration) typically involves the injection of immunocontraceptive to induce antibody production against gonadotropin-releasing hormone (GnRH), resulting in decreased production of endogenous hormones.
Immunocastration has been shown to increase live weight, hot carcass weight, average daily gain, and dressing percentage following castration when compared with surgical methods.
Although testosterone production is reduced for approximately six months after immunocastration, persistent mounting behavior, consumer concerns, and the need for a repeat, injections have made the technique less effective and desirable than traditional, physical methods.
The author is Dr. Paul R. N. Kang'ethe (BVM, UoN)