Effect of the non-steroidal anti-inflammatory drug, carprofen, on weaned sheep following non-surgical mulesing by intradermal injection of cetrimide

How Well Does Australian Animal Welfare Policy Reflect Scientific Evidence: A Case Study Approach Based on Lamb Marking

The development and substance of animal welfare policy is subject to a range of social, cultural, economic, and scientific influences that commonly vary within and between countries. Discrepancies in policy can create confusion and mistrust among stakeholders and consumers and limit the ability to create a uniform minimum level of requirements to safeguard animal welfare, as well as create a level 'playing field' for farmers when trading with other jurisdictions. The livestock sector is receiving growing scrutiny globally for real and perceived violations of animal welfare, for example, the practice of mulesing in Australia. This article explores animal welfare legislation within Australia and how it reflects the scientific evidence surrounding routine husbandry practices in sheep, including tail docking, castration, and mulesing. While there is some variation between state and territory legislation, the most notable concern is the lack of enforceable recommendations surrounding the evidence-based use of analgesia and anaesthesia for painful husbandry procedures. The age at which these procedures are recommended to be performed is relatively consistent across Australian jurisdictions, but there is a marked difference compared to international legislation. The global context of animal welfare legislation, public perception, and producer perception of these procedures are also discussed, highlighting the difficulty of creating robust animal welfare legislation that promotes a good standard of welfare that is respected worldwide whilst being practical in an Australian setting given our unique geography and climatic conditions.

Analgesia for Sheep in Commercial Production: Where to Next?

Simple Summary

Increasing societal and customer pressure to provide animals with ‘a life worth living’ continues to apply pressure on industry to alleviate pain associated with husbandry practices, injury and illness. Although a number of analgesic solutions are now available for sheep, providing some amelioration of the acute pain responses, this review has highlighted a number of potential areas for further research.

Abstract

Increasing societal and customer pressure to provide animals with ‘a life worth living’ continues to apply pressure on livestock production industries to alleviate pain associated with husbandry practices, injury and illness. Over the past 15–20 years, there has been considerable research effort to understand and develop mitigation strategies for painful husbandry procedures in sheep, leading to the successful launch of analgesic approaches specific to sheep in a number of countries. However, even with multi-modal approaches to analgesia, using both local anaesthetic and non-steroidal anti-inflammatory drugs (NSAID), pain is not obliterated, and the challenge of pain mitigation and phasing out of painful husbandry practices remains. It is timely to review and reflect on progress to date in order to strategically focus on the most important challenges, and the avenues which offer the greatest potential to be incorporated into industry practice in a process of continuous improvement. A structured, systematic literature search was carried out, incorporating peer-reviewed scientific literature in the period 2000–2019. An enormous volume of research is underway, testament to the fact that we have not solved the pain and analgesia challenge for any species, including our own. This review has highlighted a number of potential areas for further research.

Assessment of a multimodal analgesia protocol in goats undergoing claw amputation

Objective: To evaluate the anti-nociceptive, sedative and behavioral effect of multimodal analgesic drugs in goat's undergoing unilateral claw amputation. Design: A randomized experimental design. Animals: Sixteen goats were randomly assigned into 4 groups (4 bucks per group). Procedure: Animals used in this study were randomly assigned into 4 groups, four animals for each group. All goats were anaesthetized by intravenous regional anesthesia (IVRA) of the right forelimb cephalic vein with 2% lidocaine in a dose of 3mg/kg body weight (BW) before surgery. Administration of carprofen (50 mg/ml) at a dose 0.1 mg/kg BW took place before surgery on day 0 and was then repeated once daily for another 3 consecutive days postoperatively in groups Lidocaine (L), carprofen_lidocaine (CL), carprofen – romifidine - lidocaine (CRL), and carprofen – romifidine - butorphenol - lidocaine (CRBL). Heart rate (HR), respiratory rate (RR), rectal temperature (RT), serum IL-6 level, sedation score, and lameness score were determined at preset time intervals and the animals’ behavior was recorded. Results: The mean average of HR, RR and RT in IVRA treated animals was significantly increased until the end of surgery followed by gradual decrease up to 90 min post-surgery. In CRL and CRBL it showed a significant decrease compared to controls. There was a significant decrease in lameness score in CRL and CRBL treated animals from 30 min until 2 hours and for 3 days post-surgery. After injection of romifidine it showed a significant decrease of IL-6 levels compared to lidocaine and CL treated animals. Conclusion and clinical relevance: It was concluded that, the use of romifidine and buterphanol in the analgesic protocol during claw amputation in goats, alleviate pain response and potentiate the analgesic effects of IVRA. Addition of carprofen to the analgesic protocol can be used for long- term treatment of orthopedic pain in goats without complications.

Acute phase biomarkers of diseases in small ruminants: an overview

Acute phase proteins (APPs) are a large group of proteins synthesised mainly by the liver. Their production is stimulated in response to disturbances in the systemic homeostasis. It is known that each species has a specific set of APPs. Serum amyloid A and haptoglobin are the main APPs in small ruminants and their plasma concentration is changed most significantly in comparison with minor APPs such as ceruloplasmin. In general, APPs could provide valuable information on the general condition of the organism but cannot point at the exact disease. Therefore, APPs should be included as an additional indicator in clinical diagnosis. Knowledge of APPs behaviour in disease states has a remarkable potential for detecting animals with subclinical infections, determining the prognosis of clinical infection, differentiation between viral and bacterial disease, treatment monitoring, vaccine effectiveness and stress conditions. The aim of this review is to present data on APPs behaviour during some parasitic and infectious diseases as well as pathological conditions leading to aseptic inflammation and stress in sheep and goats.

A pen study evaluation of buccal meloxicam and topical anaesthetic at improving welfare of lambs undergoing surgical mulesing and hot knife tail docking

Mulesing is a painful husbandry procedure commonly used to reduce the risk of breech strike in sheep. This study assessed the behavioural (over 6 h), cortisol, haptoglobin and haematology responses to surgical mulesing plus tail hot knife docking (mulesing); modulated by a buccal meloxicam formulation (Buccalgesic), a topical local anaesthetic wound dressing (Tri-Solfen) or both agents. 24 lambs were allocated to each of: 1) Placebo and sham handled (Sham); 2) Placebo and mulesing (Mules); 3) Buccalgesic and mulesing (Mules + B); 4) Tri-Solfen and mulesing (Mules + T); 5) Placebo, Tri-Solfen and mulesing (Mules + T + P); 6) Buccalgesic, Tri-Solfen and mulesing (Mules + T + B). Compared with Mules, Mules + T had a lower cortisol response (72.5 ± 8.7 nmol/L v 122.9 ± 8.7 nmol/L) at 30 min, reduced statue standing at 2 h (3.9% v 11.4%) and increased lying (20.9-25.0% v 7.3-12.5%). Mules + B had reduced cortisol response at 6 h (48.1 ± 8.5 nmol/L), reduced Neutrophil:Lymphocyte ratio at 6 h (Mules + B: 1.25; Mules: 2.44), reduced statue standing at 2 h and 4-6 h (4.1-8.3%), and increased lying at 5 h (27.4%). Mules + B + T had lower cortisol concentrations at 30 mins (86.51 ± 8.71 nmol/L), TWCC not significantly different from Sham at 6 h (9.07 vs 8.09) and 24 h (9.05 vs 8.38). Mules + T + B had significantly lower TWCC than Mules at 12 h (9.56 vs 11.05) and 24 h (9.05 vs 10.42). Mules + T + B did not.

Sheep death and loss of production associated with flystrike in mature Merino and crossbred ewes

In eight well-managed Australian Merino and crossbred sheep flocks the adult ewes were monitored frequently for flystrike. Occurrences of flystrike and severity of strike scores were recorded, whereas bodyweights and condition scores were recorded regularly across two wool production and reproduction cycles. In these unmulesed flocks, 17% of Merino and 5% of crossbred ewes were struck, with 2% of those struck dead within 7 days of detection of the strike. For those adult ewes that survived the immediate period of the strike, the rate of loss over the following year was slightly greater than for ewes that were never struck, particularly for those with a high severity strike. Flystrike also contributed to losses of up to 2.7 (Merino ewes) and 5.2 (crossbred ewes) kg of bodyweight, and 0.3 condition score units at the time of the strike. Bodyweights were still 2 kg lower by 3 months after the strike occurred for Merinos, although condition scores returned to average levels. For ewes struck between mating and lambing, flystrike was associated with significant losses of lambs. Flystrike at severity level 1 (light) had only minor effects on wool production, but severity score 3 (heavy) reduced clean fleece weight.

Randomised trial of the bioavailability and efficacy of orally administered flunixin, carprofen and ketoprofen in a pain model in sheep

OBJECTIVE

To determine the efficacy and bioavailability of non-steroidal anti-inflammatory drugs (NSAIDs) when administered orally to sheep.

DESIGN

Randomised experimental design with four treatment groups: three NSAID groups and one control group (n = 10/group). The study animals were 40 18-month-old Merino ewes with an average weight of 31.4 ± 0.5 kg.

METHODS

Treatment was given orally at 24 h intervals for 6 days at dose rates expected to achieve therapeutic levels in sheep: carprofen (8.0 mg/kg), ketoprofen (8.0 mg/kg) and flunixin (4.0 mg/kg). Oil of turpentine (0.1 mL) was injected into a forelimb of each sheep to induce inflammation and pain; responses (force plate pressure, skin temperature, limb circumference, haematology and plasma cortisol) were measured at 0, 3, 6, 9, 12, 24, 36, 48, 72 and 96 h post-injection. NSAID concentrations were determined by ultra-high-pressure liquid chromatography.

RESULTS

The NSAIDs were detectable in ovine plasma 2 h after oral administration, with average concentrations of 4.5-8.4 µg/mL for ketoprofen, 2.6-4.1 µg/mL for flunixin and 30-80 µg/mL for carprofen. NSAID concentrations dropped 24 h after administration. Pain response to an oil of turpentine injection was assessed using the measures applied but no effect of the NSAIDs was observed. Although this pain model has been previously validated, the responses observed in this study differed from those in the previous study.

CONCLUSIONS AND CLINICAL RELEVANCE

The three NSAIDs reached inferred therapeutic concentrations in blood at 2 h after oral administration. The oil of turpentine lameness model may need further validation.

Effect on the breech and tail characteristics of Merino lambs of varying the duration of application of occlusive plastic clips as an alternative to mulesing

OBJECTIVE

The objective of the study was to determine the minimum duration of clip application required to increase the size of the perineal and tail bare areas and reduce breech wrinkle, dag or urine stain scores of Merino lambs.

METHOD

The study was conducted on a single farm in western New South Wales using 491 unmulesed lambs of a plain body type (9-14 weeks of age; mean (±SD) bodyweight 26.9 ± 5.0 kg; 82% wrinkle score 1 or 2) randomly allocated into 10 groups. Groups 1-9 included 39-46 lambs treated with the clips, which were removed at 1-7, 10 or 14 days, respectively, after application. Group 10 comprised 53 lambs that were unclipped, unmulesed controls. Visual scores, bare area measurements and bodyweights were assessed before and at 28 and 60 days following clip application.

RESULTS

Clips increased the size of the perineal and tail bare areas if left on the lambs for a minimum of 4-6 days. The increases in the size of the perineal and tail bare areas were similar to the results of previous studies. This indicates that the clips performed as expected, despite the current study being conducted on lambs with a plain body type.

CONCLUSION

When used as an alternative to mulesing, clips should remain on lambs for a minimum of 4-6 days to effectively increase the size of the perineal and tail bare areas. Further research is required to determine the degree of protection against flystrike provided by the clip method.

A review of mulesing and other methods to control flystrike (cutaneous myiasis) in sheep

Flystrike (cutaneous myiasis) in sheep has the potential to have a major impact on the welfare of significant numbers of sheep worldwide, but particularly in Australia. The main control method used in Australia, the mulesing operation to remove folds of skin from the hindquarters of the sheep, is effective in controlling the disease, but will be terminated from 2010 as a result of concerns that the operation itself has too great a negative impact on sheep welfare. Alternative treatment methods are considered, and it is proposed that they need to be appraised for each farm separately, based on the conditions prevailing and the potential to apply the different treatments. Sheep are predisposed to flystrike if their fleece is wet or contaminated with faeces or urine. Monitoring and awareness of the weather conditions will enable farmers to strategically treat their sheep with insecticides, or to observe them and treat affected animals more regularly. Frequent removal of wool by crutching, dagging and shearing will aid wool desiccation after rainfall and decrease the likelihood of fleece contamination with excreta. Some control of diarrhoea can be achieved by good grazing management and treatment of diseases that predispose sheep to the disorder. Reducing fly populations can be achieved by the use of traps, and parasitoid wasps also offer some promise. Alternative methods of removing wool and wrinkles from the hindquarters of sheep, including the topical application of quarternary ammonium compounds, phenols, caustic soda or plastic clips, have yet to be proven to be effective, without severely impacting on the welfare of the animal as well as compromising operator safety. In the long term, the breeding of sheep without wrinkles or wool on their hindquarters offers the most likely method of control, although a small proportion of sheep are affected on other parts of their body.