Sheep have a rich history, with their domestication and utilisation being an integral part of human civilisation's expansion across the world. Sheep are hardy creatures capable of living in some of the most remote and harshest locations and are extensively utilised for their meat and wool, with over 1.2 billion head worldwide in 2023. Beyond agricultural use, sheep are kept as companions and used as models for biomedical research. There is extensive research into the efficacy of various anaesthetics and analgesics and their impact on sheep, as well as investigations into methods to identify pain in sheep. Even with the long history of being raised and utilised by humans, sheep are often misrepresented as being an unintelligent species that has limited experience of pain. It can also be difficult to identify individuals experiencing pain due to their stoic nature. As such, there is still a gap in understanding of the level of pain sheep experience throughout their life in a production system and the availability of analgesic and anaesthesia resources for those that care for them.
The lives of humans and cattle have been intertwined for over 9000 years. Cattle have been worshiped as gods, sacrificed to gods, used as beasts of burden and providers of milk, meat and leather. Today, there are approximately 940 million cattle worldwide, the majority being reared for meat or milk production. Cattle are also used in research, as beasts of burden, sporting animals and pets. Both Nietzsche and Frankl acknowledged that life and suffering are entwined, both from philosophical and physical points of view. Parturition engenders pain and suffering and is notable in cattle, while misadventure and injury are a part of life for all animals. Commercial cattle production involves several elective husbandry procedures that are painful. This chapter investigates the domestication and natural history of cattle, the sources of pain and its management.
Society expects that animals brought to slaughter are killed humanely, taking care to manage and maintain their welfare. Rendering the animal unconscious while minimising pain, fear, or distress is one key expectation, while unconsciousness lasting long enough for the animal to die through loss of blood without regaining consciousness is another. A dielectric (electromagnetic) system, trademarked DTS: Diathermic Syncope® (DTS) has the potential to address these requirements. Twelve cattle were rendered unconscious using DTS with 160-200 kJ of energy delivered at 18 kW. In addition to Electroencephalography (EEG) the animals were carefully observed from the time of entry into the restraint until they had fully bled out for signs that could indicate consciousness. There was little sign of pain, fear or distress, in the restraint box or during energy application. Both EEG and behavioural observation confirmed that DTS induced Grand mal epilepsy in the cattle consistent with unconsciousness, within a few seconds of energy application. There was no rise in forehead temperature at the site of energy application while the animals were conscious. Later rises in temperature could result in superficial burns. The animals remained unconscious while the neck cut was applied and then bled strongly without regaining consciousness. The significant blood loss met the expectation of religious slaughter.
Although society desires good animal welfare at slaughter, there is a tension between some religious requirements and modern commercial stunning methods. The DTS (Diathermic Syncope®) system has been designed with a vision of relieving that tension, rendering the animal unconscious within 0-5 s, by applying 160-200 kJ of 915 MHz electromagnetic energy to the forehead, while limiting damage or changes to the tissues. To investigate this latter aspect, surface temperature at the point of application was measured using fiber optic sensors in 12 animals; application point hide skin of 3 animals was examined histologically; 7 brains were inspected and palpated shortly after energy application; and four brains were examined histologically. There were no gross morphological changes to the brain, and limited evidence of changes on histological examination. Temperatures at the point of application remained close to the ambient (29.0-36.5 °C) prior to and for the first 8-12 s of energy application (max duration of application 12 s), then rose steadily to a peak, and began to fall when energy application ceased. Maximum recorded temperature was 54.27 (± 6.56) °C, which occurred after energy application had ceased. Although small numbers of animals were included in this study, they and the process used were representative of the normal operation through the commercial abattoir. Depilation and effects on forehead skin noted on carcases after bleed-out are likely to be exacerbated by post-mortem change. These findings may comply with religious slaughter requirements.
IntroductionUnderstanding the impact of housing conditions on the stress responses in farmed saltwater crocodiles (Crocodylus porosus) is crucial for optimizing welfare and management practices.MethodsThis study employed a multi-omics methodology, combining targeted and untargeted LC–MS for metabolite, lipid, and hormone profiling with 16S rRNA gene sequencing for microbiome analysis, to compare stress responses and changes in fecal samples of crocodiles housed in single versus group pens. Metabolic responses to a startle test were evaluated through multivariate analysis, and changes post-stress were examined.ResultsA total of 564 metabolic features were identified. Of these, 15 metabolites were linked to the cortisol biosynthesis pathway. Metabolite origin analysis showed that 128 metabolites originated from the host, 151 from the microbiota, and 400 remained unmatched. No significant differences in fecal corticosterone levels were observed between single and group pens. However, metabolic profiling revealed distinct differences in stress responses: single pen crocodiles exhibited downregulation of certain compounds and upregulation of others, affecting pyrimidine and purine metabolism pathways when compared to grouped pen crocodiles, linked to altering energy associated induced stress. Additionally, fecal microbiome analysis indicated increased Firmicutes:Bacteroides (F:B) ratio in group-housed animals, suggesting greater stress.DiscussionThe study highlights that while traditional stress indicators like corticosterone levels may not differ significantly between housing conditions, metabolic and microbiome analyses provide deeper insights into stress responses. Single pens are associated with less metabolic disruption and potentially better health outcomes compared to group pens. These findings underscore the value of fecal microbiome and metabolomics in assessing animal welfare in farmed crocodiles.
For beef to be acceptable to consumers of Halal and Kosher meat, the animal must be alive at the point of exsanguination, undamaged and, if rendered unconscious prior to slaughter, able to recover from the unconscious state if not exsanguinated. A dielectric (electromagnetic) system, trademarked DTS: Diathermic Syncope® (DTS) has the potential to address these requirements. Seven cattle were rendered unconscious using DTS at 150-180 kJ of energy. Electroencephalography (EEG) was performed prior to and after DTS energy application in 6 of these animals, while they recovered consciousness, while the seventh was handled in accordance with commercial processing procedures, without the delays involved in collecting EEG data. Five animals (4 of which had EEG recorded) were returned to the holding pen after recovery and held for a period of 30 min, during which they explored their surroundings ate hay and rested. After the observation period, they were returned to restraint, DTS energy reapplied and the carcases processed for human consumption. Loss of consciousness, based on behavioural reactions, occurred within 10 s of the start of energy application, while EEG indicated the duration of insensibility to be 63 s (based on absence of eye reflexes) or more, with a long transition to full return of consciousness. Animals recovered fully from the induced unconsciousness and responded normally to environmental stimuli. No evidence of aversion was noted when these animals were returned to the restraint box a second time, some 30 min after recovery.
OBJECTIVE:To compare the behavioural responses of lambs to ring castration with or without local anaesthetic administration by single midline injection at the scrotal neck. STUDY DESIGN:Blinded, randomized block design pen study. ANIMALS:A group of 60 male Merino lambs; 6-8 weeks of age; average body weight of 18.5 ± 0.33 (mean ± standard error of the mean) kg at the time of castration. METHODS:Lambs were randomly assigned to three groups of 20: 1) NUMNUTS - lamb placed in a marking cradle and ring castrated with 1.5 mL lignocaine 2%; 2) SHAM - lamb placed in marking cradle and the scrotum manipulated as though an elastrator castration ring were applied; and 3) RING - lamb placed in the marking cradle, ring castration performed using an elastrator. Pain-related behaviours annotated for 1 full minute every 5 minutes post-procedure, from video footage collected for 2 hours post-procedure, according to a defined ethogram. RESULTS:Lignocaine administration led to significant (p < 0.05) reductions in restless behaviour at 5 and 10 minutes in NUMNUTS lambs compared with RING (mean = 0.2 ± 0.4 versus 1.0 ± 0.4, respectively) post castration. A significant (p = 0.01) reduction in foot stamping and kicking behaviour at 5 minutes post castration (mean = 1.5 ± 0.4, for RING versus 0.4 ± 0.4 for NUMNUTS) and significant (p = 0.001) reduction in the sum of all acute pain-related behaviours at 5 minutes post castration. CONCLUSION AND CLINICAL RELEVANCE:A single midline injection of local anaesthetic at the scrotal neck can alleviate the behavioural responses to ring castration in the immediate post-procedure period. However, the duration of effect was limited, which may be a result of the drug we used. Development of a longer-lasting local anaesthetic formulation is imperative to optimize pain mitigation for ring castration.
Killing of farmed saltwater crocodiles involve stunning with a penetrative captive bolt device, followed by a cut across the nape of the neck and physical destruction of the brain to ensure death. This study was a welfare-based assessment of the use of a penetrative captive bolt device in saltwater crocodiles, to determine whether it satisfies the criteria of a humane stunning method and can be regarded as a direct killing method without the need for the application of an adjunct method. Methods used were electroencephalogram (EEG), observation of post-stun behavior, and postmortem examination of gross pathology of the cranium and brain. 30 of 30 animals, demonstrated immediate and irreversible loss of consciousness. There was extensive damage to the brain in all animals, deemed to be inconsistent with cortical function and possible recovery. The CASH Special 0.22 penetrative captive bolt pistol (1.25 grain cartridge), applied to the top of the cranial plate, produced immediate and irreversible unconsciousness in all the animals studied. This method satisfies animal welfare expectations, providing crocodile processors with a technique that contributes to a humane killing process.
Saltwater crocodiles (Crocodylus porosus) are farmed in Australia primarily for their skins and meat. Commercially, they are raised in group pens as hatchlings and grower crocodiles and then moved to unitised (individual) pens for the final finishing stage when they are several years old. They will exhibit aggressive behaviour towards each other in captivity. Unitised pens can prevent animal injury and teeth marks on the skins but may result in other social restrictions. Research into behavioural housing preferences could assist the industry and inform the process of guideline development for optimal crocodile management and welfare. This study assessed the impacts of two housing systems, unitised or group pens, in 20 commercial finishing crocodiles through measuring behavioural profiles of individuals from video recordings, including housing preference when given a choice. Both pens included water and an above-water shelf, but the crocodiles in unitised pens could also access underneath the shelf. A threat perception test was applied to assess anxiety when housed individually or in groups. However, it was difficult to apply a standardised stimulus to all animals that reliably elicited a behavioural response. Further work would be needed to validate this test for commercial reptiles as the outcomes were not robust. The behavioural observation results showed clear differences in where the crocodiles spent their time across the day and in their activity levels between the pen types. However, interpretation of this variation was confounded by the physical and social differences between the pen types given the inconsistency in shelf access. Behaviours exhibited also differed given there were social opportunities in the group pens where individuals were observed engaged in both aggressive and non-aggressive contact interactions. In the free choice environment, crocodiles spent similar amounts of time in both unitised and group pens, suggesting there were features of both pen types that were attractive to the animals. However, skins were damaged from teeth marks highlighting the physical and economical risks of group housing. Further work could validate behavioural tests to quantify affective state impacts in different housing environments and whether social interactions do provide benefits for improving crocodile welfare.
The aim of this study was to assess welfare outcomes of electrical stunning as a means of restraint in farmed grower saltwater crocodiles (Crocodylus porosus). Physical handling of a stunned, unconscious crocodile is far safer for the operator than handling a fully conscious animal. Electroencephalogram (EEG) was recorded before and after the application of electrical stunning at 50 Hz or 400 Hz using an electrical stunner applied to the cranial plate (Position 1: P1–50 Hz; n = 31, P1–400 Hz; n = 29) or immediately behind the skull (Position 2: P2–50 Hz; n = 29; P2–400 Hz; n = 30). For all electrical stuns, percentage total EEG power in a 10-s epoch decreased in the alpha and beta frequency bands; and increased in the delta and lower frequencies bands. All electrical stuns resulted in increased strength of signal, based on the quadratic mean EEG power in all frequency bands of the EEG. Greatest change in power occurred in the delta frequency band, with P1–50 Hz. This was greater than with P2–50 Hz; while decibel change using 400 Hz at either position was intermediate and not significantly different from either. Application of either electrical stunner at position 1 resulted in seizure-like activity and activation in low frequencies, but at position 2 this was not consistent across all animals. The ability of the electrical stunning equipment to consistently induce recoverable unconsciousness could be ranked in decreasing order as: P1–50 Hz > P1–400 Hz = P2–50 Hz > P2–400 Hz. Based on behavioural observations, all animals in the study appeared to stunned however evaluation of duration of EEG changes indicates that use of the electrical stunning equipment at 50 Hz would allow some margin for inaccuracies in tong placement, while achieving a consistently reliable stun.
Studies in humans have shown sex differences in response to painful events, however, little is known in relation to sex differences in sheep. Understanding sex differences would enable improved experimental design and interpretation of studies of painful procedures in sheep. To examine sex differences in response to pain, 80 lambs were tested across five cohorts of 16. The lambs were penned in groups containing two male and two female lambs with their respective mothers. Lambs were randomly allocated from within each block to one of four treatment groups; FRing–Female lamb, ring tail docked without analgesia, MRing–Male lamb, ring tail docked without analgesia, FSham–Female lamb, tail manipulated and MSham–Male lamb, tail manipulated. Following treatment, lambs were returned to their pen and were video recorded for 45 mins for behavioural observations of acute pain and posture. An hour after treatment, lambs then underwent an emotional reactivity test that consisted of three phases: Isolation, Novelty and Startle. Following treatment, Ring lambs displayed more abnormal postures (mean = 2.5 ± 0.5) compared to Sham lambs (mean = 0.05 ± 0.4, P = 0.0001). There was an effect of sex on the display of acute pain-related behaviours in lambs that were tail docked (P < 0.001), with female lambs displaying more acute behaviours (mean count = +2.2). This difference in behaviour between sexes was not observed in Sham lambs. There was no effect of sex on display of postures related to pain (P = 0.99). During the Novelty and Startle phase of the emotional reactivity test, Ring lambs tended to (P = 0.084) or did (P = 0.018) show more fear related behaviours, respectively. However, no effect of sex was observed. The results of this study indicate that a pain state may alter the emotional response of lambs to novel objects and potential fearful situations. It was also demonstrated that female lambs display increased sensitivity to the acute pain caused by tail docking compared to males.
The persistent endocrinological effects of perinatal stress due to gestational immaturity in horses are unknown, although effects have been reported in other livestock species. This pilot study tested the hypothesis that persistent adrenocortical dysregulation is present in horses that were gestationally immature at birth by assessing the salivary cortisol response to exogenous ACTH.Case horses (n = 10) were recruited with histories of gestation length < 315 d or dysmaturity observable through neonatal signs. Positive controls (n = 7) and negative controls (n = 5) were recruited where possible from related horses at the same locations. Cases and positive controls received an intramuscular, low-dose (0.1 ug/kg) of synthetic ACTH (Tetracosactrin 250 mg/mL, Synacthen); negative controls received no ACTH. Saliva samples were collected from all horses at baseline T = 0 and at 30 min intervals post injection from T = 30 to T = 150. These were assayed for salivary cortisol concentration (SCC) using a commercially available ELISA kit (Salimetrics).All baseline values (T = 0) were within normal published ranges. Peak and AUC values (corrected for baseline) for case horses were significantly different (ANOVA P < .001) to positive controls, with either higher (H-cases) or lower (L-cases) SCC values, outside the 95% Confidence Interval of the reference population. There was no significant effect of breed, age, sex, test month, or location on results. The results suggest that gestational immaturity may lead to subclinical adrenocortical dysregulation, with affected horses presenting an elevated or blunted response to a low-dose ACTH stimulation, despite normal basal levels.
A novel technology for inducing unconsciousness prior to slaughter has been developed (DTS). For commercial reasons meat quality attributes are important, and impacts on endocrine responses provide an indication of animal welfare. We compared endocrine, ultimate pH and meat quality (after 1 and 10 weeks of storage) attributes of cattle carcases processed using DTS with those processed using penetrative captive bolt (CB). There were no significant differences between treatments in the change in plasma cortisol, adrenocorticotropic hormone, β-endorphin and catecholamines between baseline and immediately post-slaughter, and no significant differences in terms of pH at 24 h post slaughter. There were no significant differences in pH, shear force, TBARS or drip loss between DTS and CB samples of round and loin at week 1 and week 10 post slaughter; DTS meat was yellower at quartering (MINOLTA b* P < 0.05). At week 1, DTS loins were redder (MINOLTA a*, P < 0.05) and yellower (MINOLTA b*, P < 0.05), while DTS rounds were lighter (MINOLTA L*, P < 0.05), than CB. At week 10, there were no significant meat color differences between treatments. Processing cattle using DTS results in endocrine changes and meat quality attributes that are comparable to CB.
Docking the tail of lambs is a standard husbandry procedure and is achieved through several techniques including clamps, hot or cold knives and latex rings, the last of which is the most popular. All tail docking methods cause acute pain which can be reduced by application of local anesthetic, however precise anatomical injection for optimal efficacy requires considerable skill. This pen trial evaluated the ability of local anesthetic (LA) delivered with a dual function ring applicator/injector to alleviate acute tail docking pain. Thirty ewe lambs were assigned to one of three treatment groups (n = 10 per group): ring plus local anesthetic (Ring LA), ring only (Ring) and sham handled control (Sham). Lambs were videoed and their behavior categorized every five minutes for the first hour and every 10 min for the subsequent two hours after treatment. There was a significant effect (p < 0.001) of treatment on total active pain related behaviors in the first hour, with Ring lambs showing higher counts compared to Ring LA or Sham. Ring lambs also displayed a significantly higher count of combined abnormal postures (p < 0.001) than Ring LA or Sham lambs. Delivery of 1.5 mL of 2% lignocaine via the dual action device abolished abnormal behaviors and signs of pain in Ring LA lambs. However, lambs in the Ring LA group spent less time attempting to suckle compared to Ring and Sham lambs, suggesting that some residual discomfort remained.
The use of local anesthesia at the time of ring castration and tail docking can improve lamb welfare. However, few local anesthetics are registered for sheep, and data on their duration of effect is limited. Three studies were conducted to evaluate the efficacy of procaine (P), lidocaine (L), and bupivacaine (B) in terms of observed alleviation of behavioral responses to castration and/or tail docking in 10-min blocks in the first 60 min post-treatment. In each study, comparisons were made between two groups of lambs castrated and/or tail docked with rubber rings and either receiving the agent using the NUMNUTS® instrument (N) or receiving no anesthetic agent (RR). Acute pain behavior was lower in NL (n = 28) than RRL (n = 15) males in the first 10 min post-procedure (p < 0.05); lower in NB (n = 16) than RRB (n = 16) males in periods 10–20 min (0.05 < p < 0.01), 20–30 min (p < 0.05) and 40–50 min (0.05 < p < 0.01); lower in NB (n = 16) than RRB (n = 16) females between 20 and 40 min post-procedure (0.05 < p < 0.01); lower in NP (n = 8) than RRP (n = 7) males in period 10–20 min (0.05 < p < 0.01), and lower in NP (n = 9) than RRP (n = 9) females in periods 0–10 min (0.05 < p < 0.01), and 10–40 min (p < 0.05). Benefits were modest, and the effects of procaine appear to last longer than lidocaine, while bupivacaine is slower to take effect than either procaine or lidocaine but may provide longer-lasting pain relief. The duration of action of local anesthetics is short in sheep, and detailed behavioral evaluations are required in the first hour post-procedure to establish efficacy.
Animal-based measures are the measure of choice in animal welfare assessment protocols as they can often be applied completely independently to the housing or production system employed. Although there has been a small body of work on potential animal-based measures for farmed crocodilians, they have not been studied in the context of an animal welfare assessment protocol. Potential animal-based measures that could be used to reflect the welfare state of farmed crocodilians were identified and aligned with the Welfare Quality® principles of good housing, good health, good feeding and appropriate behaviour. A consultation process with a panel of experts was used to evaluate and score the potential measures in terms of validity and feasibility. This resulted in a toolbox of measures being identified for further development and integration into animal welfare assessment on the farm. Animal-based measures related to ‘good feeding’ and ‘good health’ received the highest scores for validity and feasibility by the experts. There was less agreement on the animal-based measures that could be used to reflect ‘appropriate behaviour’. Where no animal-based measures were deemed to reliably reflect a welfare criterion nor be useful as a measure on the farm, additional measures of resources or management were suggested as alternatives. Future work in this area should focus on the reliability of the proposed measures and involve further evaluation of their validity and feasibility as they relate to different species of crocodilian and farming system.
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.
The provision of analgesia at the time of marking has been adopted by the Australian sheep industry, but data on production benefits are lacking. In the current study, alternate lambs were provided with either meloxicam (non-steroidal anti-inflammatory drug [NSAID], n = 781) or no analgesia (NONE, n = 822) at the time of ring castration and tail docking. Six distinct management groups of lambs were studied. Lambs were weighed immediately before marking and then again at weaning. There was no significant effect of treatment on average daily gain between marking and weaning in cross-bred lambs. In Merino lambs, average daily gain was 5 g/day lower (P < 0.005) in lambs receiving NSAID, but this may not be biologically significant. Lamb losses were significantly (P < 0.05) lower in the NSAID group (1.1%) than in the NONE group (2.7%). This observation is worth validating in larger studies, particularly considering that lamb mortality is a significant cost to production and welfare concern.
Equine Caudal Cervical Morphologic Variation (ECCMV) is a congenital malformation of the caudal cervical spine distinct from the more commonly recognized Cervical Vertebral Stenotic Myelopathy (CVSM). The most common presentation of ECCMV is recognized on the sixth cervical vertebra (C6). In “normal” presentations, the transverse processes on the left and right sides have a caudal lamina projecting ventrally below the caudal vertebral body in a heel shape. With ECCMV, variations occur to the structure of the caudal ventral lamina on one or both sides of C6 and may include the seventh cervical (C7) and first thoracic (T1) vertebrae and ribs, in varying configurations. Whereas the prevalence of ECCMV is not known, it has been recognized for many years and has been reported to occur with relatively high frequency within multiple populations of domesticated horses. To date, there is no documented link between the occurrence of ECCMV and clinical signs. However, based on retrospective studies, multiple authors have recognized the potential impact on performance that this condition may have. Establishing a reliable radiographic protocol for the consistent diagnosis of ECCMV would allow quantitative, scientific evaluation of the problem and support clinicians working in this field. We present a radiographic technique, which has been illustrated by diagnosis of ECCMV in three horses and confirmation of the diagnoses in two cases via postmortem examination.
Delivery of local anaesthetic at the time of castration and tail docking (marking) could improve welfare outcomes in lambs. This study examined pain responses in lambs marked using rubber rings, with or without local anaesthetic precision injected using the Numnuts® instrument. On each of two commercial farms, 150 prime lambs aged 4 to 10 weeks, balanced for sex, were randomly allocated to 3 treatments: handled in a lambing cradle (Sham), handled and marked with rubber rings (Ring) or handled and marked with rubber rings and treated with 30 mg lignocaine using the Numnuts® instrument (NNLA). Time to mother up (one trial site only), acute pain related behaviours at 5, 20, 35 and 50 min, and postures at 10 min intervals from 60 to 180 min were recorded. NNLA lambs tended to mother up more quickly than Ring lambs (P = 0.09), and more slowly (P = 0.07) than Sham lambs. Acute pain behaviours were significantly more frequent in Ring and NNLA than Sham (P < 0.001) from 5 to 50 min. NNLA was significantly lower than Ring at 5 min (P < 0.001) and 20 min (P = 0.001). Ring and NNLA did not differ at 35 or 50 min. Abnormal postures were higher in Ring and NNLA than Sham at 60, 70, 80, 90 and 150 min (P < 0.048). Ring and NNLA did not differ at any time point between 60 and 180 min. Delivery of lignocaine with the Numnuts® instrument improved welfare outcome of lambs during the acute pain response caused by castration and tail docking with rubber rings.