Wet, wintery weather often coincides with busy calving periods and an abundance of young and vulnerable calves. A change in weather can exacerbate the environmental challenge of many calf-scour pathogens, resulting in an increase in morbidity at this time of the year.
This ‘veterinary disbudding’ has been commonplace in some areas of Australia and New Zealand for a while, but in other regions it is considered a reasonably new concept.
This article aims to de-mystify the technique of veterinary disbudding allowing dairy farmers to make an informed decision on which method of disbudding is suitable for their herd.
Most dairy calves are born with ‘horn buds’ which are freely moveable but not attached to the bony skull below.
The correct term for removal of these is ‘disbudding’.
The disbudding procedure is quicker and less painful prior to 8 weeks of age, before the horn bud has fused with the skull.
The preferred time to disbud calves is between 3 and 8 weeks.
In Australia, hot iron cautery using electric or gas disbudding irons has been used for the removal of horn buds for decades.
Calves are fully conscious but physically restrained for the duration of this process to allow the procedure to be performed safely and effectively.
After 8 weeks of age, there is fusion between the horn bud and underlying bone meaning the horns are no longer freely moveable and they require amputation.
This is generally done using guillotine-style dehorners, ‘scoop’ dehorners or embryotome wire in the case of large established horns.
New methods: Combination therapies
The routine use of sedatives, local anaesthetics and analgesics (pain relief) for the purpose of disbudding dairy calves has been embraced in the UK, New Zealand, USA, Sweden, Canada and Denmark. Regulation and legislation varies by country but there is a general acceptance that the use of these drugs for disbudding reduces the stress for calves and handlers, improves calf growth and optimises animal welfare.
So what are the available options?
|Method||Description||Advantages||Disadvantages||Who can do this?|
||Local anaesthetic is injected around the base of the horn bud prior to removal.||
“Blocks’’ the immediate pain associated with the procedure.
Allows safer removal of horn bud.
|Physical restraint still required as the calf is fully awake. Effects of local anaesthetic will subside by 1-2 hours post-procedure. Direct pain can last for 8 hours.||Veterinarians are trained to handle and administer local anaesthetic.|
||Intramuscular sedation with xylazine. Once recumbent, local anaesthetic is infused around the base of the horn bud prior to removal.||
Physical restraint is not required for horn bud removal allowing stress-free and efficient removal of horn bud.
Extra teats can also be checked for and removed as necessary.
The sedative has mild pain-relief properties but these are short-lived. Direct pain can last for 8 hours.
Risk of death (low) with any sedation.
|In addition to Method 1, veterinarians are trained to select and administer sedatives, along with the recovery of calves post-procedure.|
||Intramuscular sedation with xylazine. Once recumbent, a subcutaneous injection of long-acting pain relief, followed by local anaesthetic infusion around the base of the horn bud prior to removal.||
Virtually abolishes the pain response as the long-acting pain relief can last for up to 3 days.
Horn buds and extra teats can be removed safely and pain-free.
Improved weight gains post-procedure.
Increased cost per head and time-consuming compared to traditional method.
Risk of death (low) with any sedation.
|In addition to methods 1 and 2, veterinarians are trained to select and administer long-acting pain relief.|
*Long acting pain relief can also be used in combination with traditional disbudding and method 1.
The triple combination method is the preferred option due to its superior and sustained pain relief.
Additionally, research has also shown that this method has resulted in an 18% and 15% improvement in growth rates over the subsequent 15 and 30 days respectively.
A perceived disadvantage with all of these combination therapies is the need for a veterinarian to administer the sedative and local anaesthetic.
However, despite a common misconception of additional costs associated with veterinary services, many clinics are offering this service at a very competitive price.
Availability will vary by region but if you are interested in trying veterinary disbudding with your calves, it is worth contacting your local clinic and discussing this service with them.
Dr Gemma Chuck is a veterinary advisor at Apiam Animal Health.