Taking the headache out of dehorning
Why do we need to remove horns?
The removal of horns in dairy cattle improves animal welfare in the long term as there is a reduced risk of bruising and hide damage, improved safety during handling, increased value of the animal and reduced aggressive behaviour within the herd.
What is the difference between ‘dehorning’ and ‘disbudding’?
Most dairy calves are born with ‘horn buds’ and the correct term for removal of these is ‘disbudding’. Horn buds are freely moveable and are not attached to the bony tissue below. They remain as horn buds until ~ 8 weeks of age, after which they have grown sufficiently and have started to fuse with the underlying bone. Due to this fusion with the skull, the horns are no longer freely moveable and require amputation. This is called ‘dehorning’.
Is removal of horns painful?
There is an acute pain response following disbudding and dehorning which peaks at 30 minutes and can last for 8 hours. Many studies have measured the effect of dehorning on calves and they have repeatedly shown this pattern of pain and stress response. As a result, the disbudding and dehorning of calves in this way is a welfare concern. The negative effects of this procedure on feed intake and weight gain can last for the next 30 days.
What is the best way to remove horns?
Disbudding prior to 8 weeks of age is preferred as the procedure is quicker and less painful.
The best way to reduce the pain and stress associated with disbudding is to use hot iron cautery in combination with sedation, local anaesthesia to the area surrounding the horn bud and pain relief at the time of the procedure.
Using veterinary disbudding, the pain and stress response is virtually abolished. Growth rates (kg/day) can be increased by 18% over the first 15 days and 15% over the first 30 days, compared to calves disbudded without the combination treatment.
Who can perform this procedure?
Our veterinarians are fully trained and qualified to sedate calves, perform local anaesthesia and disbud using hot iron cautery. Disbudding in this way is less stressful for calves and handlers. Extra teats can be easily removed at the same time as this procedure.
Veterinary disbudding procedure
- CALF SELECTION: Calves should be aged between 2 weeks and 8 weeks. Sick animals should not be disbudded and the procedure should be delayed until the calf has made a full recovery.
- TIME OF DISBUDDING: Calves should not be disbudded within 6 hours of milk feeding due to the risk of aspirating milk under sedation. We aim to disbud calves early in the morning to enable a milk feed later the same day.
- SEDATION: Calves are sedated to recumbency (lying down). This needs to occur in a clean, sheltered environment with adequate ventilation. There needs to be sufficient space for calves to lie down without touching each other. This is usually the calf pen they are being reared in. Sedation reduces the ability for calves for regulate their body temperature which means that disbudding on excessively hot or excessively cold days should be avoided.
- PAIN RELIEF: A long acting non-steroidal pain relief is provided at the time of sedation.
- CLIPPING: The hair around the horn buds is clipped using electric clippers. This allows better visualisation of the horn bud enabling more accurate placement of the disbudding iron. It also reduces the smoke associated with burning hair.
- LOCAL ANAESTHETIC: A nerve block is administered to both horn buds using local anaesthetic. This takes approximately 3-5 minutes to have an effect.
- DISBUDDING: Hot iron cautery with an electric disbudding iron is used to disbud calves. In older calves where horn buds have fused to the underlying bone, amputation is required prior to hot iron cautery.
- ANTISEPTIC: Topical antibiotic is applied to both horn bud sites immediately after the procedure.
- RECOVERY: Calves must be monitored following veterinary disbudding. They should be placed on their chest, away from other calves. They should be standing within 1 hour of the procedure, although may remain partially sedated for up to 3 hours. Calves disbudded in the morning should be fully awake and active for a milk feed the same day.
- CALL THE VET IF:
- Calves remain sedated for >3 hours
- There is bleeding form the horn bud sites
- Calf behaviour is abnormal (e.g. poor appetite)
- The horn bud sites become infected