Research »   Castration

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Castration is the removal or inactivation of the testicles. In earlier times, castration was used to help control cattle used to pull plows and wagons; oxen are tamer than bulls. Castration is now used as a management tool in modern agriculture for many reasons, including to:

  • Cease the production of male hormones
  • Prevent mating of genetically inferior livestock
  • Decrease aggression to enhance on-farm safety for handlers and animals
  • Decrease costs of managing bulls (larger, stronger facilities)
  • Avoid price discounts from feedlots and meat packers
  • Produce meat with a quality acceptable to consumers (higher grade, more marbling, more consistent)

Sections

Timing

Producers should castrate bulls at the youngest age practical, and definitely before weaning. Castration of bull calves soon after birth is ideal as it results in improved animal welfare, improved health and gain in the feedlot, and enhanced marbling and tenderness compared to castration at or after weaning. Animal health and welfare risks, and animal performance impacts all increase with age. Avoid castrating during the fly and insect season.

Methods

Common physical methods of castration include surgical removal of the testes, or stopping the bloodflow to the testes using a Burdizzo or an elastrator band.

Surgical removal

Surgical removal involves making an incision into the scrotum followed by the physical extraction of both testes. This technique is most commonly performed when the calves are 3-6 weeks of age, when calves are typically also vaccinated and branded. Physical removal is also used when necessary at the feedlot, where intact males are typically 6-12 months of age. This method is rapid, and is essentially fail-safe.

Burdizzo

A Burdizzo is a specially designed clamp that is used for the physical crushing of 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 continually becoming less common in the cattle industry.  Compared to surgical castration, this method takes longer and has a higher failure rate (up to 35%), particularly with old or poorly maintained equipment.

Elastrator banding

Elastrator banding involves creating damage to the scrotal and testicular blood supply by placing a specially designed rubber rings or latex bands around the scrotum, between the testicles and the groin. This disruption of blood supply causes the testis and the scrotum to slough off 3-6 weeks later. The rubber ring technique is typically performed on newborn calves, within a few days of birth while latex bands are used for castrating older animals. This method is relatively rapid in young animals, and has a low failure rate (5%), but may increase the risk of tetanus, particularly in older animals.

“Belly nuts”: If one or both testicles is mistakenly pushed into the body cavity and the ring is placed below them, cut the band off and try again. Failing to fix these mistakes in the young calf means that the feedlot will need to conduct a painful, invasive, costly surgery in an older animal.

There is no clear evidence that either surgical or banding castration produce better animal performance.

Hormonal castration

Research on less painful alternatives to physical castration has developed methods of hormonal castration (immunocastration).  This typically involves injecting agents which induce an immune response against GnRH, a hormone responsible for inducing testosterone production in bulls.  Bulls are given an initial injection, followed by a booster 3-8 weeks later.  At about 9 days after the booster, bulls are shown to have a marked reduction of testosterone in their system.

The disadvantage to this method is that the effect lasts for only 12 -16 weeks. Within modern beef production systems, cattle are typically 12-24 months of age when they are harvested. This would mean multiple applications would be needed.  There is also an issue of the effect of accidental injection in male cattle handlers.  To date, this type of product is not licensed for use in Canada.

Concerns

Although castration is a common and effective production practice, complications may arise from the procedure, including infection, swelling, bleeding, discomfort, and pain. These complications are minimized when castration is done at the youngest age possible, proper, clean techniques and well maintained equipment are used, and through adequate vaccination.

Although castration improves carcass quality, it decreases daily gains and feed conversion ratios compared to intact bulls. However, the development and use of growth promotants within the industry have been able to offset these disadvantages to produce steers that grow rapidly and efficiently without the risks associated with feeding bulls. 

Pain Mitigation

All methods of castration are painful. Surgical castration causes more intense pain that lasts for a few days, while banding castration causes a less intense but chronic pain that lasts for over a month.

Researchers are currently studying pain associated with the various castration techniques. Within the industry, castration at birth is currently viewed as the most humane practice, based on limited research and clear evidence that the surgery is less invasive in smaller animals.

An anesthetic (e.g lidocaine) is a drug that temporarily eliminates all feeling. Local anesthetics cause numbness; general anesthetic cause unconsciousness.

An analgesic temporarily eliminates pain, but not normal sensation.

There is increasing interest in the use of anesthetic or analgesic drugs to reduce the pain associated with castration. Anesthetics need to be injected 5 to 20 minutes or so before the operation, and can provide several hours of pain relief. Injectable analgesics such as ketoprofen (Anafen), flunixin meglumine (Banamine) and meloxicam (Metacam) are longer-acting than anesthetics, and may provide some pain relief for up to a day after castration.

A number of analgesic drugs have been approved for use in beef cattle. None of these products have a specific claim for pain control following castration, but they do control swelling and pain for a variety of different conditions. These one-time injection products do not last long enough to eliminate all of the symptoms associated with band castration. Studies with experimental in-feed products (e.g. oral meloxicam or acetylsalicylic acid) have shown some potential for banded feedlot cattle, but do not appear to be practical for nursing calves on pasture.

References
  1. Adams TE, Daley CA, Adams BM, Sakurai H (1993) Testis function and feedlot performance of bulls actively immunized against gonadotropin-releasing hormone effect of implants containing progesterone and many estradiol benzoate. Journal of Animal Science 71, 811–7.
  2. Anderson DE, Muir WW. Pain management in ruminants(2005) Vet Clin Food Anim ;21:19-31.
  3. Bogucki P (1993) Animal traction and household economies in Neolithic Europe Antiquity 67, 492–503.
  4. Clutton-Brock J (1992) How the wild beasts were tamed. New Scientist 139, 31–3.
  5. Coetzee JF, Gehring R, Tarus-Sanf J, Anderson DE (2010) Effect of sub-anesthetic xylazine and ketamine ('ketamine stun') administered to calves immediately prior to castration. Veterinary Anaesthesia and Analgesia;37:566-578.
  6. Coetzee JF, Edwards LN, Mosher RA, Bello NM, O’Connor AM, Wang B, KuKanich B, Blasi DA (2012) Effect of oral meloxicam on health and performance of beef steers relative to bulls castrated on arrival at the feedlot. Journal of Animal Science 90:1026-1039.
  7. CVMA website http://canadianveterinarians.net/ShowText.aspx?ResourceID=48.
  8. Field R.A. (1971) Effect of Castration on Meat Quality and Quantity. Journal of Animal Science 32(5), 849-858.
  9. George LW In: Recent Advances in Anesthetic Management of Large Domestic Animals, E.P. Steffey (Ed.) Publisher: International Veterinary Information Service (www.ivis.org), Ithaca, New York, USA. Pain Control in Food Animals (9-Oct-2003)
  10. Gonzalez LA, Schwartzkopf-Genswein KS, Caulkett NA, Janzen E, McAllister TA, Fierheller E, Schaefer AL, Haley DB, Stookey JM, Hendrick S (2010) Pain mitigation after band castration of beef calves and its effects on performance, behavior, Escherichia coli, and salivary cortisol. Journal of Animal Science 88(2):802-810.
เกมยิงปลาออนไลน์24 ชั่วโมงLearn More

When to Castrate Calves Could Affect Weight Later On
Stacy Campbell, Extension Agent, Ellis County Kansas
http://beef2live.com/story-castrate-calves-affect-weight-later-88-112823

Castration of Calves
Ontario Ministry of Agriculture, Food and Rural Affairs
http://www.omafra.gov.on.ca/english/livestock/beef/facts/07-029.htm

Effects of Age and Method of Castration on Performance and Stress Response of Beef Cattle - Frequently Asked Questions
Alberta Agriculture and Rural Development
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/faq10883

Welfare Implications of Castration of Cattle (April 20, 2012)
American Veterinary Medical Association
http://www.avma.org/reference/backgrounders/castration_cattle_bgnd.pdf

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Acknowledgements

Thanks to Dr. Cody Creelman, Veterinary Agri-Health Services, for contributing his time and expertise to assist with this page.

This topic was last revised on February 29, 2016 at 09:02 AM.
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