Disbudding is practised in 61% of European bovine herds – in 75% of cases on young calves. In Switzerland, approximately 73% of dairy cows are hornless. The reasons for dehorning are both economic and safety-related: horned animals need more space, and horns represent an additional risk of injury. In Switzerland, dehorning is regulated in the Animal Protection Ordinance (Art. 32 AniPO and art. 16 AniPA), which stipulates that the calves to be dehorned may not be more than 3 weeks old, and that the disbudding must be performed with a hot-iron under anaesthetic and with the administration of an analgesic.
Studies on Long-Term Effects of Disbudding – Pain, Stress Reactivity and Meat Quality
(As of January 2018)
Since 2015, Agroscope and the University of Bern Vetsuisse Faculty have for the first time been studying the possible long-term consequences of disbudding in a Fondation Sur-la-Croix-sponsored project consisting of two sub-projects:
- ‘Investigations with Fattening Cattle’(Behaviour, Stress-Reactivity)
- ‘Investigations with Cattle and Calves’ (Study of the Long-Term Effects of Disbudding)
1. Investigations with Fattening Cattle (Agroscope)
This sub-project studies the influence of dehorning on the stress-reactivity, behaviour and meat quality of fattening bulls.
The experience of chronic stress can lead to changes in the reactivity of physiological stress axes (especially of the hypothalamic-pituitary-adrenal (HPA) axis). A stress-axis reactivity test – the so-called ACTH test – can be used to investigate such changes in reactivity via stimulation of the adrenal cortex. In an Agroscope study, repeated ACTH tests were performed on horned, disbudded and mixed groups of fattening bulls to determine whether horn status might have an effect on stress-axis reactivity. The results have not been published yet, but a scientific paper has been submitted.
Social and Individual Behaviour of Fattening Cattle
At present, there is a lack of studies conducted under experimental conditions that investigate the behaviour of cattle from the point of view of horn status. For this reason, both the group- and individual behaviour of fattening bulls and heifers are currently being observed in behavioural tests. Analysis of the data is still pending.
Contact: Media Office Agroscope
2. Studies on the Effects of Disbudding in Calves (Vetsuisse Faculty, University of Bern)
Pain and the Experience of Pain up to 3 Months after Disbudding
Prof. Claudia Spadavecchia, Dr. Alessandro Mirra und Dr. Daniela Casoni investigated in this study both, whether the disbudding of calves under the analgesia and anaesthesia recommended in Switzerland causes acute or chronic pain, and whether the timing of the disbudding (age of calves at time of disbudding: 1 or 4 weeks) has an effect on pain development. For this, a group of male calves were sedated on the day of the disbudding and administered analgesics locally and systemically. Part of the calves were then disbudded. The other part were merely ‘sham-disbudded’, to allow for a distinction between the possible influence of the treatment on the calf and the influence of the administration of a local analgesic on the one hand, and the effect of the disbudding itself on the other.
The results of the first part of the study show that both a local hypersensitivity to tactile stimulation and pressure (allodynia) as well as the experience of pain from non-inherently painful stimuli (hyperalgesia) persisted over the 24-hour post-operative period. This occurred irrespective of the calves’ age at disbudding (no differences between calves 1 or 4 weeks old).
The second part of the study, in which the longer-term consequences of disbudding were investigated, shows that this hypersensitivity could persist up to 105 days after disbudding. Thirty-eight per cent of the disbudded calves developed chronic trigeminal hypersensitivity. The disbudded calves had significantly higher pain scores, local hyperalgesia and allodynia than the sham-disbudded ones. Moreover, the disbudded calves (especially those disbudded at four weeks of age) exhibited an impairment of the endogenous pain-modulation system. From this, we may conclude that the consequences of the disbudding may extend far beyond the acute phase, and, irrespective of age and anaesthetisation, individual animals may develop chronic trigeminal hypersensitivity at the time of disbudding.
Mirra, A. et al., 2018. Acute pain and peripheral sensitization following cautery disbudding in 1- and 4-week-old calves. Physiol Behav 184: p. 248-260.
Casoni, D. et al., 2019. Can disbudding of calves (one versus four weeks of age) induce chronic pain? Physiol Behav 199: p. 47-55.
Determining Potential Neuropathic Changes after the Disbudding of Cattle and Calves
Prof. M. Stoffel, Dr. B. Vidondo and S. Stettler from the Vetsuisse Faculty of the University of Bern investigated possible dehorning-related morphological changes in nerve cells of the Ramus cornualis of the N. maxillaris, which is responsible for the sensitive innervation of the horn. For this, the diameter and frequency of different fibre types versus those of an unaffected nerve (N. infraorbitalis of the N. maxillaris) were analysed. The study encompassed dehorned cattle as well as the disbudded and sham-disbudded calves of Prof. Claudia Spadavecchia’s study (Sub-Project II, see above), with the result that a possible connection between the anatomical-histological findings and a heightened sensitivity to pain could also be taken into account.
The results show that there is a slight tendency towards a minor and probably clinically insignificant increase in the diameter of the nerve fibre in debudded calves. For all other measured values, there were no statistically significant differences, and hence no connection with the occurrence of chronic pain.
Stettler, S., 2016. Assessment of Potential Neuropathic Changes in Cattle after Heat Disbudding. Veterinary Medicine Dissertation, Bern
Stettler, S., Stojiljkovic, A., Mogel, H., Gaschen, V., Spadavecchia, C., Casoni, D., Stoffel, M. H. (in preparation). Assessment of Potential Neuropathic Changes in Cattle after Heat Disbudding.
Contact: University of Berne, Media Relations, email@example.com,
T : +41 31 631 41 42
Further Research Projects
Social Behaviour of Horned and Dehorned Cows (FSVO)
A project on the importance of horns in the social behaviour of cows is currently being conducted by the Centre for Animal-Friendly Housing of the Federal Food Safety and Veterinary Office (FSVO). Ethological and physiological parameters (e.g. heart rate) were recorded on commercial farms to determine whether a change in available space in the exercise area elicited differences in social behaviour between horned and dehorned cows.
Regardless of horn status, the number of confrontations decreased along with an increase in space in the exercise area. In addition, high-ranking cows exhibited more-aggressive behaviour than low-ranking cows, regardless of horn status. In the case of confrontations between two members of the same herd, horned cows exhibited a different behavioural pattern from hornless cows; confrontations in the former group were repeatedly played out without physical contact, i.e. the mere threat from the higher-ranking animal caused the lower-ranking animal to take avoidance action.
Contact: Kathrin Naegeli, FSVO, firstname.lastname@example.org,
T: +41 58 466 79 71