Disbudding and Dehorning by Ultra-Scan ©. Disbudding and dehorning in New Zealand New Zealand authorities recommend disbudding at the youngest age possible,

Disbudding and Dehorning by Ultra-Scan ©

Disbudding and dehorning in New Zealand

New Zealand authorities recommend disbudding at the youngest age possible, and chemical dehorning is not deemed to be acceptable unless it is performed within the first few days after birth. The New Zealand Code of Welfare for Painful Husbandry Procedures mandates a 9 month age limit for dehorning without attention to pain relief. 1)

Horn anatomy and growth in cattle

Horns are special adaptations of the skin. The corium is the site of horn production. If the horn but not the corium is removed, horns will resume growing. 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. 2)

Disbudding

Disbudding involves destroying the horn-producing cells (corium) of the horn bud. Horn buds are removed without opening the frontal sinus. Chemical and hot-iron disbudding methods destroy the horn-producing cells, whereas physical methods of disbudding excise them.

3)

Horn bud removed

Dehorning

Dehorning is removal of the horns after they have formed from the horn bud. Physical methods of dehorning (gouge dehorning) include the use of embryotomy wire, guillotine shears, or dehorning knives, saws, spoons, cups, or tubes. The Barnes-type scoop dehorner is commonly used for physical dehorning. Dehorning of adult cattle is associated with increased risks of sinusitis, bleeding, prolonged wound healing, and infection. 3)

A Barnes-type dehorner scoops

Technique - Ultra-Scan technicians use a hot iron, that is heated by LPG. This is suitable method for dairy or beef calves aged 2-8 weeks. The head of the iron is designed to fit

over the horn bud and burn the horn cell base. The heat prevents bleeding. Care is taken not to burn through the skull and damage underlying tissue.

Before coming on to your farm all our gear is cleaned and disinfected.

Cauterization minimizes potential medical harmful possibilities such as infections, when antibiotics are not

available.

The cauterized burn site is a sterile wound.Use of topical antibiotic after disbudding works well in reducing the risk of infection. North Island Ultra-Scan technicians apply this spray as standard procedure. South Island Ultra-Scan technicians will apply if provided.

Local anesthesia

Ultra-Scan technicians are certified by

vets to use local anaesthesia. The

anaesthesia is supplied by your vet

and where they are happy to supply

our qualified technicians we will

bring it with us to your job. Where we

cannot source it but you would like

us to use it, you only need to

order it from your vet, have it on hand

and we will apply. Check with your

local Ultra-Scan technician.

Many sources now recommend that local anesthesia be provided. Anesthesia reduces avoidance behaviors during the disbudding/dehorning procedure. Investigation of the benefits of local anesthesia (in the form of a preoperative cornual nerve block with lidocaine or bupivicaine) has produced conflict results. 4) 5)

Healing of disbudding wounds. Cautery of the skin around the horn buds, with no major involvement of bone, results in relatively superficial wounds. The classic model of

wound healing is divided into three or four sequential, yet overlapping, phases: hemostatis, inflammatory, proliferative and remodeling.

Days after:a) 4b) 14c) 30d) 30 - healthy tissue

under the scab, that forms during healing process

a

b

c

d

Post-disbudding considerations

keep calves dry for at least 24 hours (disbudding should be performed on a dry but not excessively hot day as rain and flies can introduce infection to the wound )

regularly check burn site during feed times irritation will occur due to the discomfort experienced from the burn after the local

anesthetic wears off – because of this check pens and enclosures for sharp objects, protruding wire, nails, tin edges etc.

if prolonged bleeding occurs, apply pressure for 5 minutes or phone your Ultra-Scan technician so we can re-cauterize

allergic reactions can occur with local anesthetic, if any unexpected conditions or deaths occur contact both, your vet and technician

Note: every calf is individual, some heal longer then the other

Infection may occur! Calves can contract an infection from an environment – dirty, wet, not disinfected housing.

Treating for an infection

• remove scab and clean wound immediately with antiseptic solution (i.e. Dettol; contains chloroxylenol)

• then treat with topical antibiotic spray • if infection (including swollen, painfull

area around the wound) occurs in large number of calves, animals appear depressed with loss of appetite, contact your veterinarian for advice

Infection of the frontal sinus appears as a pus coming from the wound after 1-3 weeks

Additional services provided by Ultra-Scan technicians

Extra teat removal Tagging DNA sampling Rubber ring elastration of bull

calves.

References

1) http://www.biosecurity.govt.nz/files/regs/animal-welfare/req/codes/painful-husbandry/painful-husbandry.pdf

2) http://www.thebeefsite.com/articles/2261/dehorning-of-calv

3) http://www.avma.org/reference/backgrounders/dehorning_cattle_bgnd.asp 4) http://gpvec.unl.edu/files/griffin/AnimalWellbeingArticles_Info/

AnimalWelfareDehorningCortisolStafford.pdf

5) http://www.ncbi.nlm.nih.gov/pubmed/15977616

6) http://www.biosecurity.govt.nz/about-us/our-publications/technical-papers#tail switch removal in dairy cows

7) Photos: author archive

Happy calving to everyone!Happy calving to everyone!