CVMA-ACMV

Disbudding and Dehorning of Cattle – Position Statement

September 22, 2016

Position

The Canadian Veterinary Medical Association (CVMA) supports dehorning/disbudding in cattle for human and animal safety reasons provided that disbudding is performed within the first month of life, appropriate anesthesia and perioperative analgesia are used to control the pain involved and, in the case of dehorning, bleeding is controlled. The CVMA supports selective breeding of polled cattle. 

Summary

  • Cattle without horns cause fewer injuries to other animals and humans than do horned animals.

    Where prevention of horns by genetic selection is not currently an option, calves should be disbudded in preference to dehorning.

    Individual animals subjected to disbudding or dehorning by any method should receive a local anesthetic and peri-operative analgesia.

    Any bleeding during dehorning must be controlled.

Background

  1. The bovine horn is a specialized organ of epidermal origin that is absent at birth. The cluster of cells located at the junction of the eventual horn and skin (corium) is the site of horn production. Horns begin as buds within the skin of the poll. At approximately 2 months of age, the horn buds become attached to the periosteum of the frontal bone overlying the frontal sinus. As the horns grow, the cornual diverticulum of the caudal portion of the frontal sinus extends into the most proximal portion of the horn.
  1. Disbudding involves destroying the corium of the horn bud without significant periosteal damage. Dehorning is amputation of the horns after they have formed from the horn bud. Tissue damage (e.g., from disbudding and dehorning) results in activation and release of intracellular contents from damaged cells, inflammatory cells, and nerve fibers. Physiologic, neuroendocrine, and behavioral changes indicative of pain and distress are observed following dehorning and disbudding (1,2).
  1. Cattle without horns cause fewer injuries to other animals and humans than horned animals (3).
  1. In beef production, there is no evidence that there is a growth or productivity difference attributable to or associated with the horned gene (4,5). Where prevention of horns by genetic selection (6) is not currently an option, calves should be disbudded in preference to dehorning (7).
  1. Although some of the evidence is contradictory, the use of caustic paste to remove horn buds in young calves might cause less acute pain, but the discomfort from prolonged chemical burns can last longer than that from burns following the use of a hot iron. In addition, damage can be caused if the caustic paste spreads to surrounding tissues or other animals (7).
  1. Individual animals subjected to disbudding or dehorning should receive, at the very least, a local anesthetic and peri-operative analgesia (8,9). A cornual nerve block using local anaesthetic is normally effective within 5 minutes of administration and can last for several hours, but its efficacy should be tested using a needle prick around the horn bud prior to use of a hot-iron (10). Handling of calves and administration of a cornual nerve block should not be stressful and is markedly less stressful than hot-iron disbudding without local anaesthesia (11). 
  1. The National Farm Animal Care Council Dairy Code of Practice for the Care and Handling of Dairy Cattle (2009) stipulates that disbudding and dehorning must be performed with pain relief and that dehorning must also be performed with bleeding control (12).
  1. Calves that are disbudded using local anesthesia, sedation, and non-steroidal anti-inflammatories have improved milk intake and higher growth rates, and decreased neuroendocrine and physiologic stress response associated with the procedure (7,13). In addition, calves show a reduction in post-dehorning pain-associated behaviors including head shaking, ear flicking, and head rubbing when anesthesia, sedation, and non-steroidal anti-inflammatories are used in combination (14).
  1. Dairy farmers have the ability to recognize post-dehorning pain (15), providing an opportunity for food animal veterinarians to engage in meaningful conversation and education with dairy producers to develop on-farm protocols to improve calf health and welfare.

References

  1. Vickers KJ, Niel L, Kielbauch LM, et al. Calf response to caustic paste and hot-iron dehorning using sedation with and without local anesthetic. J Dairy Sci 2005;88:1545-1559.
     
  2. Taschke AC, Folsch DW. [Ethological, physiological and histological aspects of pain and stress in cattle when being dehorned] Tierarztl Prax 1997;25:19-27.
     
  3. Knierim U, Irrgang N, Roth BA. To be or not to be horned-consequences in cattle. Livestock Science 2015;179:29-37.
     
  4. Prayaga KC. Genetic options to replace dehorning in beef cattle – A review. Aust J Agric Res 2007; 58:1-8.
     
  5. Stookey JM, Goonewardene LA. A comparison of production traits and welfare implications between horned and polled bulls. Can J Anim Sci 1996;76:1-5.
     
  6. Schafberg R, Swalve HH. The history of breeding for polled cattle. Livestock Science; SI: Alternatives for Dehorning in Cattle. 2015;179:54-70.
     
  7. Stafford KJ, Mellor DJ. Addressing the pain associated with disbudding and dehorning in cattle. Appl Anim Behav Sci 2011;135:226-231.
     
  8. Stafford KJ, Mellor DJ. Dehorning and disbudding distress and it’s alleviation in calves. Vet J 2005;169:337-349.
     
  9. Stookey JM. The veterinarian's role in controlling pain in farm animals. Can Vet J 2005;46:453-458.
     
  10. Fierheller EE, Caulkett NA, Haley DB, Florence D, Doepel L. Onset, duration and efficacy of four methods of local anesthesia of the horn bud in calves. Vet Anaesth Analg 2012;39:431-435.
     
  11. Graf B, Senn M. Behavioural and physiological responses of calves to dehorning by heat cauterization with or without local anaesthesia. Appl Anim Behav Sci 1999;62:153-171 
     
  12. Code of Practice for Care and Handling of Dairy Cattle. National Farm Animal Care Council (2009). Available from: http://www.nfacc.ca/codes-of-practice/dairy-cattle. Last accessed June 14, 2016.
     
  13. Bates AJ, Eder PA. The effect of combinations of a local anesthetic, sedative, and non-steroidal anti-inflammatory on daily growth rate and milk intake of dairy calves after disbudding. Vetlife, Canterbury, NZ. Proceedings of the 28th World Buiatrics Congress WBC July 27-August 1, 2014. Cairns, Australia.
     
  14. Faulkner PM, Weary DM. Reducing pain after dehorning in dairy calves. J Dairy Sci 2000;83:2037-2041.
     
  15. Gottardo F, Nalon E, Contiero B, et al. The dehorning of dairy calves: Practices and opinions of 639 farmers. J Dairy Sci 2011:94;5724-5734.


(Revised July 2016)