What happens when something stresses a calf? At a physiological level, it sets off a chain of chemical reactions in response to the stressful event. The calf’s brain tells the adrenal glands to make the hormone cortisol. Cortisol increases the blood pressure, makes the heart beat more strongly, diverts blood to the vital organs and increases blood sugar levels – making the calf ready for the “fight or flight” response. In effect, cortisol heightens an animal’s survival mechanism.
However, there is a trade-off. Cortisol also decreases white blood cell movement to infection sites and decreases their ability to fight pathogens. It also decreases the production of antibodies. It means that in times of stress, in order to deal with the problem at hand, the body turns down or turns off the immune system. While this increases short-term survival (say if the calf was running away from a lion!), it also means the calf may succumb to a disease that they would otherwise have been able to fight off, had there not been a stressful event.
Sources of stress for calves include things outside the normal daily routine, such as weaning, transport, vaccination, environmental extremes (hot or cold) and painful procedures, such as ear tagging and disbudding.
Each stressful event can suppress the immune system, but if you combine them and the stress is greater disease is even more likely to result. To minimise the risk of disease in calves, stagger husbandry procedures by several days and if possible, don’t perform husbandry procedures at times of environmental stress.
Reduce the effect of stressful situations through calm and quiet handling, adequate handling facilities for husbandry procedures such as vaccination, mitigating environmental extremes (such as using blankets in cold weather) and providing pain relief at disbudding.
The Vet Group’s CalfWise Disbudding service uses a combination of sedation, local anaesthetic and long-acting anti-inflammatories prior to hot-iron cautery to remove the horn buds. This combination of sedation and pain relief has been shown to minimise cortisol levels in the blood and reduce the risk of a disease setback following the procedure of disbudding.
Linda Whiting, who with her husband Andrew rear around 150 calves per year, has been disbudding with sedation and pain relief since 2015. “When The Vet Group started offering the service, we thought it would be worth trying because it seemed a better alternative for the health and welfare of our animals,” Linda says.
“It is so much calmer; especially using our locking headbails, there is no chasing animals around a pen and the sedation means there is no rush or upsetting the calves”. Linda says the biggest benefit has been the way animals recover from the procedure. “Using long acting anti-inflammatory has had such an impact. The calves are noticeably brighter in the days following disbudding, and don’t have the same obvious soreness that we used to see. Also, we find that the wound is cleaner and heals much quicker.”
Veterinary disbudding using sedation, anaesthetic and pain relief should be performed when calves are 2 to 8 weeks of age. For more information or to make a booking, call Farm Services on 1300 838 700 or talk to your veterinarian.
Sedate calves to recumbancy
Area around buds clipped
Local anaesthetic administered
Hot iron cautery
Horn bud removed
Topical antibiotic applied