Abstracts to Bibliography


Lambs were handled only or castrated and tail docked at five, 21 and 42 days of age by either surgery, rubber ring or rubber ring and Burdizzo. Plasma cortisol was measured in blood samples taken before and at 12, 24, 36, 48, 60, 72, 84, 96, 138 and 180 minutes after castration and docking. Pre-treatment and peak cortisol values were highest in five-day-old lambs. The peak cortisol values, at each age, were similar for surgery and rubber ring groups. However, the peak occurred earlier after surgery and rubber ring Burdizzo than after rubber ring only treatment. The cortisol peak was 28 nmol litre-1 lower after rubber ring Burdizzo than surgery or rubber ring only. Plasma cortisol returned to pretreatment values within 84 minutes after rubber ring Burdizzo, 96 to 138 minutes after rubber ring only but not within 180 minutes after surgery. The changes in plasma cortisol together with the changes in behaviour suggest that the rubber ring Burdizzo method of castration and docking of lambs at all ages, was probably the least painful of the methods tested.

The behavioural and plasma cortisol changes in groups of six lambs, five to six days old, were used to compare the acute effects of four methods of castration and tail docking: Burdizzo, standard sized and small rubber rings, and a combined method in which the application of a standard rubber ring was followed immediately by the application of the Burdizzo just distal to it. A control group was also included, Active behaviours such as foot stamping and restlessness increased markedly only after the treatments with rubber rings. Less time was spent in abnormal postures, and the increases in plasma cortisol were least after the combined method. It was concluded that the lambs treated by all the methods suffered considerable acute pain, for up to three hours in some cases, but that the combined method produced the least pain as judged by the behavioural and physiological indices measured, and that the small rubber rings produced more intense pain for a shorter time than the standard rubber rings.


Kent JE, Molony V, Graham MJ 1998 Comparison of methods for the reduction of acute pain produced by rubber ring castration or tail docking of week-old lambs. VETERINARY JOURNAL 55 (1): 39-51 JAN 1998

Behavioural and plasma cortisol changes were recorded for groups of eight SuffolkxGreyface lambs subjected to castration or tail docking using rubber rings with and without local anaesthetic treatment. Immediately after application of the rubber ring, local anaesthetic (2x0.2 ml 2% lignocaine) was administered either by needle and syringe or by high-pressure needleless injection into each side of the neck of the scrotum or tail at the site of the ring, or by high pressure needleless injection into the testes before ring-application. In other groups, the innervation to the scrotum or tail was disabled by crushing with a powered bloodless castrator just proximal to the ring. Measurements were recorded in groups of control (handled) lambs, with and without local anaesthetic treatment. Application of local anaesthetic by high pressure needleless injection had little effect on either plasma cortisol values or behaviour of control lambs. For castration, application of the bloodless castrator and/or local anaesthetic at the ring site reduced the peak plasma cortisol concentration by 50% (P less than or equal to 0.01), the incidence of active behavioural responses by 80 and 64% (P less than or equal to 0.01) respectively, and the time spent in abnormal postures by 68 and 59% (P less than or equal to 0.01) respectively. Both methods were effective in reducing pain for tail docking [active behavioural responses reduced by more than 80% (P less than or equal to 0.01) and abnormal postures by 56% (P less than or equal to 0.01)], although local anaesthetic was more effective, reducing the peak cortisol by 60% (P less than or equal to 0.01) [crushing by 44% (P > 0.05)]. Injection of local anaesthetic into the testes was less effective than injection into the neck of the scrotum at the site of the ring [reduction in abnormal lying postures (P < 0.05), 45 vs 71%, respectively]. The rapid action, effectiveness, and ease of application of these experimental methods may provide the basis for commercially viable methods for reducing the acute pain produced by rubber ring castration and tail docking of lambs.

Kent JE, Jackson RE, Molony V, Hosie BD 2000 Effects of acute pain reduction methods on the chronic inflammatory lesions and behaviour of lambs castrated and tail docked with rubber rings at less than two days of age. VETERINARY JOURNAL 160 (1): 33-41 JUL 2000

Lesions were produced by castration and tail docking of two-day-old Dorset-cross lambs with elastrator rings with (RRla) and without (RR) local anaesthetic or after destruction of the innervation by crushing close to the ring (Brr). The lesions were monitored twice weekly for six weeks and the behaviour of handled controls (H), RR and RRla lambs was recorded for two 3 h periods 10, 20, 31 and 41 days after treatment.

There was no significant effect of castration and tail docking, with or. without pain reduction methods, on daily liveweight gain. In die Err lambs, the dead tails were cast 19 days earlier than from RR and RRla lambs. The time taken for the scrotal lesion to reach maximum severity was halved in Err and RRla lambs, although the maximum severity of the lesion was unaffected by the methods of pain reduction. During the four 6 h behavioural observation periods, RR lambs showed a significant increase in the mean (+/-sd) frequency of foot stamping (RR13 +/- 13; H2 +/- 2.5), tail wagging (61 +/- 26; 15.6), head turning to the scrotum and inside hind-leg (12 +/- 10; 1 +/- 1). Less abnormal behaviour was found after RRla than after RR treatment. This unexpected finding may be evidence of long-lasting increases in pain sensitivity after an episode of intense acute pain in young animals. (C) 3000 Harcourt Publishers Ltd.

Mellor DJ, Stafford KJ, Todd SE, Lowe TE, Gregory NG, Bruce RA, Ward RN 2002 A comparison of catecholamine and cortisol responses of young lambs and calves to painful husbandry procedures.
Aim To compare the changes in plasma concentrations of noradrenaline, adrenaline and cortisol in lambs after ring castration plus tailing and in calves after dehorning with or without prior local anaesthesia. Methods Male lambs were castrated and tailed with rings and calves were dehorned by amputation using a scoop with or without prior local anaesthesia. Blood samples were taken before and after treatment and plasma concentrations of noradrenaline, adrenaline and cortisol were determined. Results Castration plus tailing of lambs resulted in a rapid increase in noradrenaline concentrations, a lack of an adrenaline response and a marked increase in cortisol concentration. There were similar changes in catecholamine concentrations in calves that were dehorned both with and without local anaesthetic, with adrenaline being elevated within 5 min of treatment and noradrenaline exhibiting a more protracted response. Dehorning caused a marked cortisol increase which was reduced to control concentrations by local anaesthesia for as long as the associated nerve blockade lasted. Conclusions The very short-lived adrenaline responses in calves were attributed to dehorning-induced nociceptor input leading to sympathetic stimulation of the adrenal medulla. The longer lasting noradrenaline responses in lambs and calves were thought be due to 'wash-out' of noradrenaline from damaged tissue associated with rings and amputation wounds, respectively.

The behavioural responses of groups of seven lambs were compared with control groups after castration and tail docking by rubber rings, application of a Burdizzo clamp in addition to a rubber ring and after surgical castration at rive, 21 and 42 days. All methods at all ages produced changes in behaviour which were interpreted as indicative of considerable pain. The rubber ring groups showed most changes in behaviour at all ages. The rubber ring with Burdizzo groups showed least changes and some lambs in these groups showed much less response than others. The surgical groups showed some behavioural responses which were different, both qualitatively and quantitatively to those in other groups. It is concluded that indices used for recognition and assessment of acute pain received conditional support, that modification of the rubber ring with Burdizzo may provide the least painful method without local anaesthesia and that age had little effect on the responses.

Molony V, Kent JE, Robertson IS 1995 Assessment of acute and chronic pain after different methods of castration of calves. APPLIED ANIMAL BEHAVIOUR SCIENCE 46 (1-2): 33-48 DEC 1995

Four groups of Ayrshire calves (n=8 each) were castrated at 1 week of age by either surgery, crushing by a Burdizzo, rubber ring or a combination of the Burdizzo and rubber ring methods. Responses of castrated calves were compared with a control group (n=8) of handled calves. Plasma cortisol was measured in blood samples taken during the first 3 h after castration. Observations of behaviour were made for 3 h immediately after castration, and for 3 h each afternoon for the first 4 days and then on every third day to 48 days after treatment. An assessment of the castration site (lesion score) was made after each observation period and the calves were weighed every twelfth day. Acute changes in behaviour and plasma cortisol were consistent with those reported previously, namely that increases in active behaviours, abnormal postures and plasma cortisol occurred in the first 3 h after castration. The behavioural response to both surgical and Burdizzo castration was characterised by immobile postures. The combined Burdizzo and rubber ring method produced a significant reduction in the activity (count per 3 h period) of two behaviours (foot stamping/kicking (11.9) and easing quarters (13.3)) compared with the use of a rubber ring alone (27 and 23.7, respectively). During the 48 days after rubber ring treatments there was an increase in the calves' concern with the site of castration, indicated by a significantly (P<0.01) increased incidence of licking which was associated with increased abnormal standing, with slow movements of the tail, alternate lifting of the hindlegs and head turning as the integrity of the skin broke down. If these indices are valid, they demonstrate that considerable acute and chronic pain is associated with rubber ring methods of castration of calves and that the chronic pain can last for at least 42 days.

Molony V, Kent JE 1997 Assessment of acute pain in farm animals using behavioral and physiological measurements. JOURNAL OF ANIMAL SCIENCE 75 (1): 266-272 JAN 1997
In this paper various aspects of animal pain and methods for its assessment are considered. The responses of lambs and calves to castration and of lambs to tail docking are used to illustrate quantitative approaches to the recognition and assessment of acute pain in farm animals. The validation of physiological and behavioral measurements for assessment of pain is examined by relating measurements made from young lambs, after a range of treatments, to an independent ranking of the order of severity of the treatments.


Molony V, Kent JE, Hosie BD, Graham MJ 1997 Reduction in pain suffered by lambs at castration
VETERINARY JOURNAL 153 (2): 205-213 MAR 1997
The acute pain produced by bloodless castrators was studied by comparing the behavioural and plasma cortisol changes in groups (n=8) of 3-week-old Dorset cross lambs after castration with a 22 cm (9 '') Burdizzo, a new power assisted castrator and by a combined method using a Burdizzo and elastrator ring. The time spent in abnormal postures (52-58 min) and the peak cortisol response (110-120 mmol l(-1)) were similar for the three methods, although the powered castrator produced a more sustained response. The Burdizzo method halved the incidence of active behaviours compared with the powered castrator and combined methods (16 versus 30, 32 counts). Intratesticular local anaesthetic administered 2 min before the Burdizzo castrator and combined method, or intramuscular injection of the non-steroidal anti-inflammatory drug diclofenac, 20 min before the application of a Burdizzo, significantly reduced the peak plasma cortisol response to 80 nmol l(-1). Diclofenac also significantly reduced the time spent trembling or in abnormal postures.

Molony V, Kent JE, McKendrick IJ. Validation of a method for assessment of an acute pain in lambs.  APPLIED ANIMAL BEHAVIOUR SCIENCE 76 (3): 215-238 MAR 26 2002

Acute pain following different methods of rubber ring castration and tail docking (CTD) was assessed using behavioural and physiological methods. Validity was determined by showing how accurately lambs were allocated, to their appropriate treatment groups. Six groups of seven lambs, 5-6 days old, were subjected to treatments, ranked before the experiment, by the amount of tissue damaged and its sensitivity to pain (anaesthesia), in decreasing order of severity. (1) castration and tail docking; (2) bilateral castration; (3) unilateral castration; (4) short scrotum castration; (5) short scrotum castration with local anaesthesia; (6) handled. A further group (n = 7) of tail docked only lambs acted as a tail docking control for castration and tail docked lambs. Changes in plasma cortisol concentration; 14 postures and 11 active behaviours were recorded for 180 min. Principal component analysis (PCA) and discriminant analysis (DA) helped determine the combinations of indices that most accurately allocated lambs to their appropriate groups. In a PCA, using all individual indices from the lambs, the first two components accounted for 45% of variation in the data. The same indices when used for DA allocated 79% of the lambs to their appropriate group (60 min data). Values for 30, 90, 120 and 180 min were 50, 55, 48 and 48%, respectively. Measurement was simplified by combining indices: total-incidence of active behaviours, relating to movements of limbs, tail and head plus vocalisation; VSS-time spent dog sitting, lying normally with trembling or with partial extension of hind limbs, and statue standing; V4LL-lying with full extension of the hind limbs; AbS-abnormal standing, excluding statue standing. These combined indices improved accuracy of allocation to 60, 79, 71, 64 and 60% for 30, 60, 90, 120 and 180 min. Inclusion of increases in plasma cortisol did not improve the accuracy for 60 min data. A simplified index consisting of V4LL and REW (movements of limbs and tail) correctly allocated 74% (60 min data, 64% for 30 min data). After combining treatment groups, to represent severe, mild or moderate pain the combined indices permitted correct allocation of 91% and the simplified indices 83% of lambs to their appropriate groups (60 min data).

It is concluded, that measuring activities involving the limbs and tail and the time spent lying with full extension of the hind limbs for 30-60 min, separated the severity of acute pain from the testes, scrotum and tail into six levels with >60% accuracy and into three levels with >80% accuracy. Awareness of these indices and their limitations should improve training for animal pain assessment. Crown Copyright (C) 2002 Published by Elsevier Science B.V All rights reserved.

Peers A, Mellor DJ, Wintour EM, Dodic M 2002 Blood pressure, heart rate, hormonal and other acute responses to rubber-ring castration and tail docking of lambs. NEW ZEALAND VETERINARY JOURNAL 50 (2): 56-62 APR 2002
AIM: To examine cardiovascular, hormonal and other physiological responses of 2-month-old lambs to rubber-ring castration and tail docking. METHODS: Twenty-two male lambs, well accustomed to handling and prepared with femoral artery and jugular vein cannulae, were studied during a 5 h control period and, at least 2 days later, for 1 h before and 4 h after castration and tail docking using rubber rings. Pressure recordings were made via femoral cannulae and blood samples for analysis of plasma constituents were taken from jugular cannulae. RESULTS: Mean systolic, diastolic and mean arterial blood pressure, heart rate and the plasma concentrations of adrenocorticotropic hormone (ACTH) and cortisol all increased markedly during the first 1 h after ring castration and tail docking. Although plasma ACTH and cortisol concentrations had returned to control levels by 2.5-3 h, blood pressures and heart rate were still elevated 4 h after ring application. In contrast, there were no significant changes in mean plasma concentrations of renin, electrolytes, minerals, glucose, lactate, urea, creatinine, total carbon dioxide and total proteins, plasma osmolality or the haematocrit after ring application. There were no significant changes in the mean values for any parameter during the 5 h control period or the I h period before ring application. CONCLUSION: Systolic, diastolic and mean arterial blood pressure and heart rate may be more sensitive than plasma ACTH or cortisol concentrations as indices of low-grade pain induced by ring castration and tail docking. Alternatively, it is possible that by 4 h after ring placement a small shift in sympathetic tone still persists in the absence of low-grade pain.

Calves of six, 21 and 42 days were either handled (controls) or castrated by Burdizzo, by surgical or by rubber ring techniques and their behaviour and plasma cortisol monitored for three hours after treatment. The rubber ring caused significant increases in active behaviour and abnormal postures for two hours compared with handled or castrated by Burdizzo and surgical techniques, and surgical techniques resulted in a significant increase in abnormal standing, particularly in the first 30 minutes. Abnormal behaviour and posture were recorded less frequently in six-day-old calves. The mean cortisol peaks for six-, 21- and 42-day-old calves were, respectively, 36, 31 and 23 nmol litre(-1) in the handled groups; 60, 43 and 48 nmol litre(-1) in the rubber ring groups; 77, 50 and 62 nmol litre(-1) in the Burdizzo groups; and 106, 63 and 107 nmol litre(-1) in the surgical groups. The greatest cortisol response occurred in 42-day-old surgically treated calves and the shortest response after Burdizzo castration. These responses suggest that irrespective of age, all methods of castration studied caused acute pain. Burdizzo castration appeared to produce the least pain, particularly in younger calves.

Stafford KJ, Mellor DJ, Todd SE, Bruce RA, Ward RN 2002 Effects of local anaesthesia or local anaesthesia plus a non-steroidal anti-inflammatory drug on the acute cortisol response of calves to five different methods of castration. RESEARCH IN VETERINARY SCIENCE 73 (1): 61-70 AUG 2002
The cortisol response of calves to different methods of castration (ring, band, surgical, clamp) with or without local anaesthetic, or local anaesthetic plus a non-steroidal anti-inflammatory drug were recorded. All methods of castration caused a significant cortisol response and by inference pain and distress. Band castration caused a greater cortisol response than ring castration but the responses were eliminated by local anaesthetic. The cortisol response to surgical castration, by traction on the spermatic cords or by cutting across them with an emasculator, was not diminished by local anaesthetic but when ketoprofen was given with local anaesthetic the cortisol response was eliminated. Local anaesthetic did reduce the behavioural response to cutting the scrotum and handling the testes. Clamp castration caused the smallest cortisol response which was reduced or eliminated by local anaesthetic or local anesthetic plus ketoprofen respectively, but this method of castration was not always successful. (C) 2002 Elsevier Science Ltd. All rights reserved.

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                                            Revised: 20-10-08