Management of pain in production animals

Does Parity Influence the Magnitude of the Stress Response of Nellore Cows at Weaning?

Most studies investigate the impact of stress at weaning on calves; however, little is known about the responses of cows, and whether they would differ according to parity. This study aims to investigate whether parity would influence the weaning stress response in beef cows. Thirty pregnant Nellore cows with their respective calves were randomly allocated to five paddocks and two females from each parity group were placed in the paddocks. There was an interaction (p < 0.05) between parity and evaluation days regarding cortisol, where on d + 7, the higher concentration was observed for multiparous cows. There was an interaction (p < 0.05) between parity and evaluation day for red blood cells (RBC), hematocrit (HCT), and hemoglobin (HB), whereby higher RBC counts on d + 4 were observed for multiparous cows. For HCT and HB, on all post-weaning collection days, higher values were observed for multiparous cows. The day of evaluation had an (p < 0.05) effect on all recorded behaviors, except for rumination (p > 0.05). Nellore cows, regardless of parity, underwent behavioral and physiological changes on abrupt weaning. Physiological parameters indicated that the magnitude of stress was greater in multiparous cows.

Time of day modified the time required for semen collection with electroejaculation and slightly affected the quality of fresh semen in rams

The aim was to compare some stress responses to electroejaculation (EE), and the quality of fresh semen, when ram semen is collected at dawn (06:00 h), noon (12:00 h), or evening (18:00 h). Twelve Corriedale rams were used, and semen was collected from four rams at each study time on three different days, with a Latin-square design. The time required for EE, the number of vocalizations emitted, heart rate, and rectal temperature were recorded, and fresh semen was evaluated. The time required for EE was shorter at evening than at dawn and noon (399.3 s, 480.6 s, and 460.2 s respectively; pooled SEM = 72.1; P = 0.03). The percentage of sperm with progressive motility was greater at noon than dawn (59.7% and 50.3%; pooled SEM = 5.8; P = 0.05). Curvilinear velocity was greater at dawn than evening (117.0 µm/s and 95.5 µm/s; pooled SEM = 7.1; P = 0.04), slow linear velocity was greater at evening than at dawn and noon (13.1 µm/s, 9.3 µm/s, and 8.5 µm/s respectively; pooled SEM = 1.7, P = 0.05), and the slow average path velocity was greater at evening than dawn and noon (16.2 µm/s, 11.7 µm/s, and 10.8 µm/s respectively; pooled SEM = 1.9, P = 0.05). In conclusion, the collection time modified the time required for electroejaculation and had only slight effects on the quality of fresh semen. Overall, the time of the day appears to have only slight effects on semen collection and quality.

Sperm collection by electroejaculation in small ruminants: A review on welfare problems and alternative techniques

There are different perspectives on whether there should be use of electroejaculation (EE) for semen collection because it can be stressful and painful for the males when this technique is imposed. In the present review it is examined 1) the effects of EE on animal welfare and semen quality in domestic and wild small ruminants, 2) benefits and limitations of administering anaesthetics and sedatives prior to EE, 3) advantages/disadvantages of transrectal ultrasonic-guided massage of the accessory sex glands (TUMASG) as an alternative to EE, and 4) benefits of administering hormones, such as oxytocin or PGF2α analogues (which stimulate the contractility of the male accessory sex glands), prior to EE and TUMASG. In general, the administration of anaesthetics, sedatives or hormones reduces the pain and stress caused by EE, and can improve sperm quality, but results may vary depending on the species. The use of anaesthetics is, however, not devoid of risks and pre-EE administration of sedatives, or oxytocin or PGF2α analogues, can aid sperm collection mitigate risks. The TUMASG is less stressful than EE, but its effectiveness varies greatly among species, and it can only be performed by trained personnel. Prior administration of the hormones may also result in a reduction in the period needed to induce ejaculation with use of TUMASG procedures.

Behavioral Signs Associated With Equine Periapical Infection in Cheek Teeth

No studies have focused on dental pain signs associated with periapical infection in cheek teeth (CT) of horses. Moreover, the ability of owners to recognize signs of dental pain in horses has not been reported. We hypothesized that periapical infection will usually induce pain that manifests in the behavior of the horse. Removing the infected tooth will reduce the expression of such behaviors. Owners of 47 horses whose CT had been removed because of periapical infection participated in this study. They filled an internet-based questionnaire including 23 questions about eating behavior, bit behavior, and general behavior observed before and after the operation. The number of signs exhibited by each horse before and after CT removal was compared using Wilcoxon signed-rank sum test. Values of P < .05 were considered significant. Before the operation, avoidance behaviors, such as evading the bit, difficulties in eating, and even asocial or aggressive behaviors were commonly reported by the owners. Removing the infected tooth significantly reduced the number of these behavioral patterns expressed by the horses (P < .001 for each group of behaviors), suggesting that they could be associated with dental pain. Half of the cases had been diagnosed during a routine dental examination, indicating that many owners did not realize that certain undesirable behavioral patterns of their horses might be associated with dental pain. These findings highlight the importance of training owners to recognize behavior potentially related to dental pain in horses and that routine dental examinations are essential for ensuring horses' well-being.

Postpartum ketoprofen treatment does not alter stress biomarkers in cows and calves experiencing assisted and unassisted parturition: a randomised controlled trial

Dystocia is considered painful and stressful for both the dam and the calf, although systematic evidence of this is limited. Few studies have investigated biochemical markers of stress and pain postpartum and whether any adverse effects are ameliorated by administration of analgesia. In this study, cow-calf pairs experiencing both mild to moderate farmer assistance and no assistance at parturition were randomly assigned to either treatment or placebo group in a two-by-two design (animals subject to veterinary intervention were excluded). The treatments were the NSAID ketoprofen or saline, administered within three hours of parturition. Blood samples taken in the immediate postpartum period, and at 24 hours, 48 hours and 7 days after parturition, were analysed for plasma concentrations of creatine kinase and cortisol (cows and calves) and plasma L-lactate and total protein concentration (calves). Stress biomarkers were highest in the immediate postpartum period and declined over time (P<0.05). Cow plasma cortisol was higher in animals experiencing assisted parturition in the immediate postpartum period (P=0.023); by 24 hours no difference was evident. Intervention with NSAID analgesia did not result in beneficial changes in stress biomarkers. Based on biomarkers alone, this suggests limited benefits of NSAID treatment in unassisted or mild to moderately assisted parturition.

Ejaculation does not contribute to the stress response to electroejaculation in sheep

Electroejaculation procedures (EEPs) provoke stress; nevertheless, ejaculation produces physiological changes similar as those usually used to measure stress responses. The application of EEP to animals that cannot ejaculate-as ewes-may be useful to discriminate the responses induced by ejaculation from those provoked by EEP. The aim was to determine the stress response to EEP in rams and ewes. The EEPs were applied to 10 rams and 10 ewes during the non-breeding season, and the number of vocalizations, the heart rate, rectal temperature, serum cortisol concentration, biochemical and haematological parameters were measured. Overall, EEP provoked increases in cortisol concentration, glycaemia, rectal temperature and concentration of creatine kinase (all them: p < .0001) as well as relative concentration of granulocytes (p = .003) and absolute granulocyte concentration (p = .0002) in both, rams and ewes. Heart rate, relative concentration of lymphocytes (p = .001), haematocrit (p = .02) and haemoglobin (p = .045) decreased in animals from both genders after EEP. Besides, cortisol (p < .0001), rectal temperature (p = .002) and glycaemia (p = .001) were greater in ewes than rams, and creatine kinase also tended to be greater in ewes than rams (p = .054). On the other hand, the number of animals that vocalized (p = .006), white blood cells (p = .02) and absolute lymphocytes (p = .02) were greater in rams than ewes. The general trends show a similar pattern of stress responses in animals from both genders. Therefore, we concluded that ejaculation does not contribute to the stress response provoked by the EEP. This procedure also provokes muscular damage and probably pain.

Experience with the delegation of anaesthesia for disbudding and castration to trained and certified livestock owners

Background

Anaesthesia is mandatory for disbudding and castrating calves and lambs of any age, in Switzerland. According to the “anaesthesia delegation model” (ADM), anaesthesia for disbudding calves <3 weeks of age and castrating calves and lambs <2 weeks of age may be administered by certified farmers. Experience with this unique model is not available. The aim was to evaluate the experience of the veterinary practitioners with the ADM. The response rate was 42%. The survey consisted of one questionnaire for each procedure. Procedure I was the delegation of anaesthesia for disbudding calves and procedures II and III were anaesthesia for castrating calves and lambs.

Results

Procedure I was performed with local anaesthesia in all farms of 51.8% of the veterinary practices, while this was only 39.3% and 7.6% for procedures II and III (p < 0.001). Anaesthesia for procedure I was administered technically correctly by farmers in at least 66% of the farms of 58.3% of the practitioners, while this was 45.4% and only 23.6% for procedures II and III (p < 0.001). The ADM was assessed as a moderate to very good model to reinforce the legal obligations for procedures I, II, or III by 74.8%, 76.5% and 62.0% of the veterinary practitioners (p < 0.005).

Conclusions

The delegation of anaesthesia to certified farmers may be a promising model to reinforce the obligation to provide local anaesthesia for disbudding and castrating calves, but to a lesser extent for castrating lambs.

Differences in attitudes of farmers and veterinarians towards pain in dairy cows

Attitudes towards pain and the use of analgesics in dairy cows were evaluated based on a questionnaire answered by 137 Danish veterinarians and 189 Danish dairy farmers. Respondents were asked to score the perceived pain associated with a number of diseases in dairy cows on a scale from 1 (no pain) to 10 (very painful) assuming that no analgesics were used. Additionally, they were asked whether they agreed or disagreed with a number of statements regarding pain and use of analgesics in cows. A large variability in pain scores for individual diseases was found among both farmers and veterinarians. The same disease was scored as 'very painful' by some respondents and as 'not painful' by others; however, farmers and veterinarians generally agreed which diseases were painful and which were not. Farmers considered most of the disease conditions to be slightly more painful than veterinarians but were less likely to use analgesics.

The stress response of frequently electroejaculated rams to electroejaculation: hormonal, physiological, biochemical, haematological and behavioural parameters

Electroejaculation (EE) is a technique widely used to collect semen in ruminants, which produces a stress response with negative effects on animal welfare. The aim of this paper was to characterize the stress response during conventional EE in rams that have been frequently electroejaculated. Blood samples were collected since 20 min before and until 120 min after electroejaculating 10 rams. Electroejaculation affected hormone concentration, as cortisol increased, and testosterone decreased after EE. Heart and respiratory rate increased 10 min after EE. Several blood parameters, such as glycaemia, an increase in total protein and creatine kinase concentrations and a decrease in haematocrit, haemoglobin, red blood cell and alkaline phosphatase concentrations. The rams vocalized 13.8 ± 2.4 times, and the largest length of vocalizations during EE was associated with the numbers of pulses in which the rams ejaculated. In this paper, we provide a complete characterization of the stress response to EE in rams. We showed that although rams have been frequently electroejaculated, an important stress response including changes in respiratory rate, testosterone concentrations, haematological and biochemical parameters were observed, besides the changes in cortisol concentrations and heart rate, suggesting that rams were not habituated to EE. In addition, we described the main parameters of vocalizations and its relation with the moment of EE. The information displayed on the frequent use of EE in the rams should be considered in relation to the welfare implications.

Pain Detection and Amelioration in Animals on the Farm: Issues and Options

Pain in nonhuman animals is a difficult concept to identify and measure. This article briefly describes the consequences of pain in animals on the farm and explains the reasons for the minimal use of analgesics in farmed animals. Pain can have implications for both animal welfare and economics. The reasons for a low use of analgesics in farmed animals include the lack of recognition of animal pain owing to the apparent lack of anthropomorphically identifiable behavioral changes, concern over human food safety, and lack of research efforts to develop safe analgesics for farm use. Treatment cost relative to the benefits expected is another hindering factor. Interventions to minimize pain must begin with developing objective and practical measures for pain identification and measurement at the farm level. A suggested use of a combination of different behavioral and physiological indicators would help to identify pain in animals. To facilitate continued usage of the methodologies on the farm it also is necessary to evaluate the economic implication of the pain alleviation intervention.

Pilot epidemiological study of attitudes towards pain in horses

This preliminary study investigated the attitudes, and evaluated the current practice of a sample of the veterinary profession in the UK in relation to the management of pain in horses. In June 2001, a questionnaire was posted to 260 veterinarians in specialised equine practice, and 140 veterinarians in general practice with a significant equine caseload. There was a 25 per cent response rate to the questionnaire, which recorded information about the availability and prescription of analgesic drugs, the factors influencing the selection of analgesics and their administration, and estimates of the severity of pain associated with selected clinical conditions. There were considerable variations in the practices applied to manage pain in horses, implying that there are similar attitudinal barriers to the optimal management of pain in horses as have been identified in other domestic spedes.