Search

Overdose of carbon dioxide gas (CO₂) is a common euthanasia method for rodents; however, CO₂ exposure activates nociceptors in rats at concentrations equal to or greater than 37% and is reported to be painful in humans at concentrations equal to or greater than 32.5%. Exposure of rats to CO₂ could cause pain before loss of consciousness. We used 2 standardized loss of righting reflex (LORR) methods to identify CO₂ concentrations associated with unconsciousness in Wistar, Long???Evans, and Sprague???Dawley rats (n = 28 animals per strain). A rotating, motorized cylinder was used to test LORR while the rat was being exposed to increasing concentrations of CO₂. LORR was defined based on a 15-second observation period. The 2 methods were 1) a 1-Paw assessment (the righting reflex was considered to be present if one or more paws contacted the cylinder after the rat was positioned in dorsal recumbency), and 2) a 4-Paw assessment (the righting reflex was considered to be present if all 4 paws contacted the cylinder after the rat was positioned in dorsal recumbency). Data were analyzed with Probit regression, and dose-response curves were plotted. 1-Paw EC 95 values (CO₂ concentration at which LORR occurred for 95% of the population) were Wistar, 27.2%; Long???Evans, 29.2%; and Sprague???Dawley, 35.0%. 4-Paw EC 95 values were Wistar, 26.2%; Long???Evans, 25.9%, and Sprague???Dawley, 31.1%. Sprague???Dawley EC 95 values were significantly higher in both 1- and 4-Paw tests as compared with Wistar and Long???Evans rats. No differences were detected between sexes for any strain. The 1-Paw EC 95 was significantly higher than the 4-Paw EC 95 only for Sprague-Dawley rats. These results suggest that a low number of individual rats from the strains studied may experience pain during CO₂ euthanasia.

General anesthesia induces a reversible loss of consciousness (LOC), a state that is characterized by the inability to feel pain. Identifying LOC in animals poses unique challenges, because the method most commonly used in humans, responding to questions, cannot be used in animals. For over a century, loss of righting reflex (LORR) has been used to assess LOC in animals. This is the only animal method that correlates directly with LOC in humans and has become the standard proxy measure used in research. However, the reporting of how LORR is assessed varies extensively. This systematic literature review examined the consistency and completeness of LORR methods used in rats and mice. The terms 'righting reflex,' 'anesthesia,' 'conscious,' 'rats,' 'mice,' and their derivatives were used to search 5 electronic databases. The abstracts of the 985 articles identified were screened for indications that the study assessed LORR in mice or rats. Full texts of selected articles were reviewed for LORR methodological completeness, with reported methods categorized by 1) animal placement method, 2) behavioral presence of righting reflex, 3) duration of LORR testing, 4) behavioral LORR, and 5) animal position for testing LORR. Only 22 papers reported on all 5 methodological categories. Of the 22 papers, 21 used unique LORR methodologies, with descriptions of LORR methods differing in at least one category as compared with all other studies. This variability indicates that even papers that included all 5 categories still had substantial differences in their methodological descriptions. These findings reveal substantial inconsistencies in LORR methodology and reporting in the biomedical literature likely compromising study replicability and data interpretation.

This prospective study evaluated oral transmucosal pentobarbital sodium at three doses in 110 wild-caught wild birds requiring euthanasia. Birds received transmucosal pentobarbital at five (430 mg/kg), six (516 mg/kg), and seven times (602 mg/kg) the intravenous dose for mammals. Time to first effects and loss of consciousness, presence of pupillary light and corneal reflexes, apnea, and asystole were recorded each minute. When asystole was not achieved at 5 minutes, IV pentobarbital was administered. Combining data for all doses, loss of consciousness occurred at a median (range) of 2 minutes (0-4.75 min), apnea at 3 minutes (0-6 min), and asystole at 4 minutes (0.5-5 min). Loss of consciousness and apnea occurred significantly faster in the 602 mg/kg dose group than in the 430 mg/kg group (p = 0.009, difference of 0.6 ± 0.2 min; p = 0.024, difference of 0.7 ± 0.3 min), respectively. Apnea and asystole were achieved in 80/110 birds within 5 minutes. Oral transmucosal pentobarbital results in rapid loss of consciousness and respiratory arrest and provides a reliable alternative euthanasia method compared to intravenous administration.

To ensure animal welfare at slaughter, rapid stunning is required to render the animal deeply unconscious. In cattle, captive-bolt stunners are typically used for this purpose. However, with regard to their impact force and maximum length of approximately 120 mm, such captive-bolt stunners are not suitable for stunning water buffaloes due to anatomical characteristics of the skull. In water buffaloes the bone layer is thicker and the distance from the point of attachment of the captive-bolt stunner to the relevant brain region is longer. For this reason, a special bullet-shooting stunner was developed, which is similar in size and handling to a standard captive-bolt stunner, but instead of a bolt, it fires a bullet. Actually, even two bullets can be loaded so that a follow-up shot can be fired immediately if necessary. In this study, the bullet-shooting stunner was tested using two different types of hunting ammunition for stunning water buffaloes during regular slaughter., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests to report., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Animal disease preparedness plans including depopulation guidelines are paramount to prevent the spread of emerging infectious diseases but difficult to implement for swine under field conditions. However, water-based foam (WBF) is currently an approved and successfully deployed depopulation methodology in poultry. Therefore, the reliability of WBF as a depopulation method and the effectiveness and irreversibility of consciousness and consequential mortality in pigs of different ages was assessed across two trials. Trial 1 investigated the time to loss of consciousness and cessation of cardiac activity in nursery pigs (n = 72) at six different foam immersion time points (2.5, 5, 7.5, 10, 12.5 and 15 min) when placed in a 1.47 m 3 (1.2 × 1.2 × 1.02 m, length × width × height) plastic bulk container. One pig per replicate was implanted with an ECG bio-logger. Irreversible loss of consciousness was observed after a 5-min immersion. The average (SD) time to development of a fatal arrhythmia from the initiation of the foam application was 7.3 min (1.82 s). Trial 2 aimed to validate the findings from Trial 1 in 75 larger cull sows across three replicates (n = 25). Sows were loaded into a 41-m 3 sealed trailer (12.2 × 1.5 × 2.24 m), immersed in WBF and left undisturbed for 5 min post foam-filling completion. Six pigs in each replicate were implanted with an ECG bio-logger. A 5-min dwell time resulted in irreversible loss of consciousness and subsequent mortality in all cull sows. The average time (SD) to cessation of movement and fatal arrhythmia post foam-filling completion was 2.2 min (34.8 s) and 8.7 min (138.0 s), respectively. While a 5-min immersion in WBF induced irreversible loss of consciousness and death in both trials, a 7.5-min dwell time followed by observation for confirmation of death post WBF removal would be advisable for pigs of all sizes., (© 2022 The Authors. Transboundary and Emerging Diseases published by Wiley-VCH GmbH.)

Although physical restraint without anesthesia is a common way to immobilize microtines in field settings, tagging can cause pain and stress, and escape-response movements may reduce marking quality. To evaluate if inhaled isoflurane may be a tool to minimize these issues, we anesthetized free-ranging voles (Microtus and Myodes spp.) undergoing subcutaneous injection of a passive integrated transponder tag and dorsal fur clipping. We anesthetized 24 voles for short-duration anesthesia using two 0.2-mL isoflurane doses in a simple drop-chamber system. We used the first dose to induce unconsciousness and the second dose to immediately restore unconsciousness after the vole regained consciousness from the first dose. Median induction times were 54 s for the first dose (interquartile range [IQR], 47-61) and 50 s for the second dose (IQR, 38-55). Median recovery times were 33 s for the first dose (IQR, 26-60) and 62 s for the second dose (IQR, 35-104). No mortalities occurred during the holding period. The technique was simple, inexpensive, and effective. We therefore recommend using isoflurane delivered in a drop chamber when tagging or marking microtines in the field to improve handling., (© Wildlife Disease Association 2022.)

In this study, the occurrence of repeat stunning, deviations in placement and direction of stun shots, and the occurrence of reflexes/reactions following stunning with a pneumatically powered captive-bolt stunner in comparison with a cartridge-fired captive-bolt stunner in cattle were assessed. Repeat stunning and deviations in placement and direction of the stun shots were less frequent (p < 0.01) with the use of a pneumatic stunner in all cattle. The rate of repeat stunning and deviation from the ideal place and direction of stun shots were lower (5.81%, 24.75%, and 9.60% of all animals, respectively) when a pneumatic stunner was used in comparison with cartridge-fired captive bolt (18.32%, 34.03%, and 47.38% of all animals, respectively). The stunning quality was assessed on the basis of evaluation of signs observed following the stun shot. A pneumatic stunning resulted in a significant reduction of occurrence of signs particularly in bulls in comparison to cows, for which a cartridge-fired stunner already provides an adequate stunning. Our study provides evidence that pneumatic stunning has the potential to be a more effective method than cartridge-fired stunning from the viewpoint of the welfare of slaughtered animals. Pneumatic stunning ensures a high quality of stunning in both bulls and cows., (© 2022 Japanese Society of Animal Science.)

1. There is a need to humanely kill moribund or injured broiler birds on-farm with no reasonable chance of recovery. Two experiments evaluated the efficacy of three commercially applicable killing methods; manual cervical dislocation (CD), mechanical cervical dislocation with the Koechner Euthanising Device (KED) and a non-penetrative captive bolt device (Zephyr-EXL; ZEXL), at 7, 21 or 35 d of age, on their ability to induce insensibility (unconsciousness and loss of brain stem reflexes) and death.2. Experiment one assessed the damage to the cranial-cervical region resulting from the methods applied to cadavers of cull birds (n = 180) by radiography and gross pathology observation.3. Experiment two evaluated the latency to insensibility and death when cull broiler birds (n = 240) were killed by CD, KED or ZEXL, using behavioural and reflexive indicators. Insensibility and death were measured by the absence of pupillary light, palpebral blink and nictitating membrane reflexes and cessation of rhythmic breathing, cloacal winking and convulsions. Analysis of variance for the main effect of the method was performed to determine the differences.4. In experiment one, only the Zephyr resulted in skull fractures. A higher number of vertebral fractures occurred with KED application compared to CD, at 21 and 35 d.5. In experiment two, indicators of sensibility were absent earliest with the ZEXL (μ < 2 s); then,CD (μ = 28 s) and were longest with KED (μ = 47 s), at 21 and 35 d. Cloacal winking and convulsions ceased earlier after CD (88 s), compared to either KED (124 s) or Zephyr (118 s). Death after a single application occurred 100%, 100% and 98% of time for CD, KED and ZEXL, respectively.6. Overall, all methods were efficacious at inducing insensibility and death. Insensibility occurred earliest with ZEXL, whilst death occurred earliest with CD. KED resulted in the longest time to insensibility and death.

Within the insensitization by electronarcosis and the bleeding processes performed at the pig's slaughterhouses, there are some factors that hinder the achievement of an adequate slaughter of these animals, being this a critical phase in which animal welfare must be guaranteed; the objective of this study was to evaluate and compare the efficiency of insensitization by electronarcosis and two types of bleeding direction (horizontal and vertical). Dependent variables were measured as indicators of animal welfare (absence of the corneal reflex, absence of reflex of sensitivity to painful stimuli, attempts to reinstatement or posture recovery and vocalization), after the stunning and bleeding process, in four slaughterhouses of national category in "Eje Cafetero", Colombia. The methodological approach included the binomial distribution, descriptive statistics, hypothesis testing and statistical significance. The results show that the efficiency of the insensitization procedures and type of bleeding direction depends on multiple aspects, including the tranquility of the animals during their handling, the correct position of the insensitization clamps, the amperage used and the time between insensitization and bleeding. In this way, the analysis of possible preventive and/or corrective measures includes: Continuous training and supervision of the personnel in charge of carrying out the procedures, the need to immobilize pigs prior to their insensitization process, the continuous monitoring of process variables and the appropriate vascular cutting that ensures animal's death prior to their entrance into the scalding machine., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: This study aims to identify the correlation between bispectral index (BIS) value and modified Glasgow Coma Scale (MGCS) score in dogs with altered level of consciousness (ALOC)., Design: This prospective, observational, clinical study was conducted from February 2016 to March 2017, and follow-up was conducted until the death of dogs or their discharge from the hospital., Setting: This study was performed at the Small Animal Teaching Hospital., Animals: A total of 31 client-owned dogs (males, 20; females, 11) with ALOC and MGCS score <18 with no restrictions for age, breed, sex, and body weight were included. Dogs that received neuromuscular blocking agents before MGCS score evaluation were excluded., Interventions: BIS values were measured using the Covidien BIS Loc 2 Channel OEM module and a pediatric 4 sensor with a bifrontal application pattern., Measurements and Main Results: Minimal databases of initial neurological assessment, blood profiles, and chest and skull radiographs were developed. In addition, MGCS scores and BIS values were recorded. The mean BIS values for mild, moderate, and severe brain injuries were 89.14 ± 6.52, 77.21 ± 9.82, and 50.58 ± 27.04, respectively. Correlation analysis revealed a significantly positive relationship between BIS values and MGCS scores (r = 0.75; P < 0.001)., Conclusions: The significant correlation observed between MGCS scores and BIS values in dogs with ALOC demonstrated the usefulness of BIS as an alternative to MGCS for monitoring consciousness in patients with ALOC caused by traumatic brain injury, encephalitis, etc., (© Veterinary Emergency and Critical Care Society 2020.)

The identification of the heart rhythm during an episode of transient loss of consciousness (TLOC) is considered the reference standard method to elucidate the underlying aetiology. This study aimed to characterise heart rhythm in dogs during TLOC using Holter and external loop recorder monitoring. We retrospectively reviewed 24-h Holter monitoring and external loop recorder tracings from 8084 dogs. Heart rhythms from dogs that experienced TLOC during the recording was analysed to identify rhythm disturbances that occurred during episodes of TLOC. Electrocardiograms (ECGs) were subsequently categorised into Type 1 (ventricular arrest), Type 2 (sinus bradycardia), Type 3 (no/slight rhythm variations), and Type 4 (tachycardia). Transient LOC was documented in 92 dogs over 230 episodes of TLOC. Percentage of cases with ECGs compatible with each classification were as follows: 72.1%, Type 1; 6.1%, Type 2; 20.9%, Type 3; and 0.9%, Type 4. Cardiac rhythm during the TLOC could have been a consequence of a neurocardiogenic mechanism in 46.7% cases, while intrinsic rhythm disturbances of the sinus node or of the atrioventricular node were diagnosed in 31.5% cases. In two cases, tachycardia was the possible cause of the TLOC. ECG patterns in dogs presenting with multiple TLOC episodes were completely reproducible during each episode. TLOC in dogs was primarily caused by ventricular arrest. Most dogs with TLOC had electrocardiographic finding suggestive of a reflex or neurally-mediated syncope, but one third had an ECG more suggestive of a conduction disorder. Distinguishing these two entities could help inform diagnostic, therapeutic, and prognostic plans., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Rainbow trout, Oncorhynchus mykiss, is an important fish in European freshwater aquaculture. This industry sector is dominated by small family-owned enterprises located in rural areas. A large percentage of rainbow trout produced by these small enterprises is marketed directly and killed on demand and not processed in commercial processing plants. EU and national regulations stipulate that fish shall be stunned prior to killing and slaughter. The overall objective of this study was to monitor how stunning interventions were integrated into the production chains of German conventional trout aquaculture in order to safeguard animal welfare during stunning and killing. For this, the stunning and slaughtering processes were monitored on 18 rainbow trout farms in various German federal states. During the on-farm research, (i) the stunning success, (ii) injuries related to the stunning procedure, (iii) duration between stunning and killing, and (iv) visible responses at the time of slaughtering were assessed as welfare indicators. In addition, haematological and biochemical blood parameters were measured as indicators for physiological stress. Due to the fact that stunning interventions should induce a loss of consciousness in fish, in a laboratory study, it was examined whether the absence of the brainstem/ behavioural responses, opercular movements (OM) or eye-rolling reflex (vestibulo-ocular reflex, VOR) was correlated with the stage of insensibility., Results: The majority of rainbow trout farms applied manual percussion (38%) or electrical stunning (48%), while on 14% of the farms, the fish were stunned by electrical stunning which was immediately followed by manual percussion. After percussive stunning, about 92.3% of the rainbow trout displayed no OM or VOR as brainstem/ behavioural indicators of consciousness. This percentage varied on farms which applied electrical stunning. While on the majority of farms, 95 to 100% of the fish were unconscious according to the observation of brainstem/ behavioural indicators, the stunning intervention was less effective on farms where rainbow trout were stunned at current densities below 0.1 A dm 2 or for a few seconds only. The laboratory study confirmed that the absence of brainstem/ behavioural indicators correlated with the absence of visually evoked responses (VER) of the brain to light stimuli as a neuronal indicator of insensibility. Therefore, the brainstem/ behavioural signs can be used to interpret the stage of insensibility in rainbow trout. A stage of insensibility could safely be induced by exposing portion-sized rainbow trout to an electric current density above 0.1 A dm 2 . This was not influenced by the orientation of the electric field., Conclusions: In conventional aquaculture, rainbow trout can effectively be stunned by manual percussion or electrical stunning. Consciousness can be monitored by the absence of opercular movements or the eye-rolling reflex, which are lost approximately at the same time as neurological responses like VER. For safeguarding animal welfare during stunning and killing of rainbow trout in conventional production processes, the stunning process requires careful attention and the operating personnel need to be trained in using the stunning devices and recognising indicators of consciousness.

This study quantified the welfare of 423 cattle and water buffalo in four Bangladeshi slaughterhouses to identify facility and species-specific factors that influence welfare. The majority of animals arrived at the slaughterhouse with injuries, signs of dehydration and oculo-nasal discharge. During slaughter, buffalo experienced more stabbing at the throat (21%), compared to local cattle (10%, P = 0.011), and significantly more cuts to the neck during slaughter (5.1 ± 1) than Hariana (3.9 ± 1) or local cattle (3.6 ± 1.1; P < 0.001). These results indicated that welfare compromise is common to all species, but that the risk to buffalo was greater. Partial severing of carotid arteries was common and affected time to unconsciousness. There was a statistical interaction between facility and species on the time taken for animals to reach unconsciousness, suggesting that welfare within a location could be improved; however, animal welfare was compromised at all facilities. Immediate welfare improvements could be made by training for effective halal slaughter, and future welfare improvements could be gained by improved facility infrastructure for restraint and halal approved pre-slaughter stunning.

Low atmospheric pressure stunning (LAPS) is a novel approach to pre-slaughter stunning of chickens using progressive hypobaric hypoxia by the application of gradual decompression (280s cycle) according to a set of prescribed pressure curves. Low atmospheric pressure stunning produces a non-recovery state. Concerns have been raised relating to the possible pathological and welfare consequences of expansion of air in the body during LAPS. In a randomised trial, we compared the gross pathology of broilers exposed to LAPS with a control group euthanised by intravenous injection of pentobarbital sodium (60 mixed sex broilers per treatment). The birds were exposed to each treatment in triplets and all birds were subject to necropsy examination to detect and score (1 to 5, minimal to severe) haemorrhagic lesions or congestion for all major organs and cavities (e.g. air sacs, joints, ears and heart) as well as external assessment for product quality (e.g. wing tips). Behavioural data (latency to loss of posture and motionless) and chamber cycle data (temperature, humidity, pressure and oxygen availability) confirmed that LAPS had been applied in a manner representative of the commercial process. All of the organs observed were structurally intact for both treatment groups. No lesions were observed in the external ears, oral cavity, tracheal lumen, crop and air sacs of birds from either treatment group. There was no difference between treatments in the wingtips, nasal turbinates, thymus, biceps femoralis and colon. Haemorrhagic lesions were observed in the calvaria, brains, hearts and lungs of both treatment groups, but lesions in these areas were more severe in the LAPS treatment group. It was not possible to distinguish between pathological changes induced by decompression or recompression. In the barbiturate group, more severe haemorrhagic lesions were observed in the superficial pectoral muscles as well as greater congestion of the infraorbital sinuses, liver, spleens, duodenum, kidneys and gonads. These findings provide evidence that LAPS did not result in distension of the intestines and air sacs sufficient to cause changes, which were grossly visible on postmortem examination. There was also no evidence of barotrauma in the ears and sinuses. The pathological changes observed in the barbiturate treatment were as expected based on barbiturate toxicity. Low atmospheric pressure stunning appears to produce pathological changes by a variety of well-established mechanisms, and while these pathological data have limited value as welfare indicators, the results confirm that organ integrity was not compromised by the process.

Hind limb post stunning kicking in properly stunned unconscious cattle is a safety hazard for employees. Three different captive bolt lengths of 15.2 cm (STRD), 16.5 cm (MED), and 17.8 cm (LON) were evaluated for amount of tissue damage and hind limb kicking in a Jarvis USSS-1 pneumatic stunner. The air pressure setting was 1378.95 to 1447.90 pKa for all captive bolts. All 45 test cattle were rendered unconscious with a single shot. There was a trend (P = .06) for less kicking to occur when the 16.5 cm length bolt was used in the stunner. Visual appraisal of the brains on the split heads indicated that the shortest bolt caused the least amount of brain damage. The brainstems were intact for all cattle regardless of captive bolt treatment. Young fed English, Continental European, and Holstein steers and heifers can be effectively stunned without visible brainstem disruption., (Published by Elsevier Ltd.)

The electroencephalographic (EEG) responses of 31 bulls (zebu crossbred cattle) stunned with either pneumatically powered Jarvis penetrating (PCB) or non-penetrating captive bolt (NPCB) was examined. Animals were organized into two treatment groups: PCB (n = 20); and NPCB (n = 11) stunning, both using airline pressures of 220 psi (1517 kPa). All bulls shot with PCB (n = 20/20) had patterns of EEG activity that were inconsistent with consciousness. Of the cattle shot with NPCB 82% (n = 9/11) showed waveforms suggesting complete unconsciousness. After stunning two NPCB bulls had periods of normal EEG activity and maintenance (Ptot, delta, theta, beta) or increased (alpha) spectral power compared to pre-treatment values, indicating incomplete concussion. The study showed that pneumatic PCB stunning was effective in rendering all bulls unconscious, while NPCB was less effective. This highlights the potential animal welfare risks associated with NPCB compared to PCB stunning of mature bulls in commercial abattoirs., (Copyright © 2019. Published by Elsevier Ltd.)

The captive bolt device has been used for stunning cattle at abattoirs for more than 100 years and is now one of the stunning devices used most widely. The aim of this review article was to assess the effects that are decisive during cattle slaughter on the quality of stunning with the use of a captive bolt stunning device. The basis of effective stunning is the use of a suitable type of device, with the speed of the bolt and the kinetic energy corresponding to the anatomical parameters of the slaughtered animal. The importance of the regular cleaning and maintenance of stunning devices and monitoring of the effectiveness of stunning goes without saying. The immediate loss of sensibility in the animal must occur after the first shot. The effectiveness of the stunning process can be quantified by regular monitoring of the behavior of animals after stunning with an emphasis on the loss of reflexes (corneal reflex, regular breathing, attempts to regain physiological posture) and checks on the shot location on the skulls of slaughtered animals., (© 2019 Japanese Society of Animal Science.)

DTS: Diathermic Syncope® (DTS) is a novel system for rendering animals insensible prior to slaughter, utilizing microwave energy to induce a rise in temperature in the brain to a point at which the animal is expected to lose consciousness. During development and optimisation of the system, two trials were carried out utilizing non-anaesthetized adult cattle, to gather data on behavioural outcomes and EEG changes following energy application. In trial1, ten cattle received DTS treatments (high energy >290 kJ, n = 3; low energy <200 kJ, n = 4; and intermediate 200 < 290 kJ, n = 3), and seven received captive bolt stunning, prior to exsanguination. In trial 2, following improvements to the efficiency of energy delivery, 20 cattle received DTS (200-360 kJ). Post treatment EEG was characterized by seizure-like activity and reductions in 95% spectral edge and median frequencies; with EEG suppression persisting for at least 80 s up to over 4 min post treatment application. Animals showed: Loss of posture, Loss of corneal responses; Loss of withdrawal response (pinprick); Eye staring, not following movement. The animals remained unresponsive to stimuli for up to 4 min post DTS, and behavioural expression of distress was not observed. Seventeen of the 30 animals showed indications of returning reflex responses after 100 s post treatment, suggesting that animals receiving lower energy applications may recover from the stun., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Cultured meat is a promising product that is derived through biotechnology that partially circumvents animal physiology, thereby being potentially more sustainable, environmentally friendly and animal friendly than traditional livestock meat. Such a novel technology that can impact many consumers evokes ethical, philosophical and religious discussions. For the Islamic community, the crucial question is whether cultured meat is halal, meaning compliant with Islamic laws. Since the culturing of meat is a new discovery, invention and innovation by scientists that has never been discussed by classical jurists (fuqaha'), an ijtihad by contemporary jurists must look for and provide answers for every technology introduced, whether it comply the requirements of Islamic law or not. So, this article will discuss an Islamic perspective on cultured meat based on the original scripture in the Qur'an and interpretations by authoritative Islamic jurists. The halal status of cultured meat can be resolve through identifying the source cell and culture medium used in culturing the meat. The halal cultured meat can be obtained if the stem cell is extracted from a (Halal) slaughtered animal, and no blood or serum is used in the process. The impact of this innovation will give positive results in the environmental and sustain the livestock industry.

Background: Common carp Cyprinus carpio is an important food fish in Central Europe, which in some regions is consumed as part of local tradition. The majority of carp are sold by small retailers and not processed in commercial processing plants. The overall objective of this study was to monitor how animal welfare is safeguarded during the stunning and slaughtering of carp for retail sale. For this, the stunning and slaughtering process was monitored on 12 carp farms. Four welfare-related parameters were assessed: (i) stunning success, (ii) injuries related to the applied stunning method, (iii) time between stunning and slaughter, and (iv) visible responses of carp during slaughtering. In addition, indicators of physiological stress were measured. In order to analyse whether the absence of behavioural indicators of consciousness after electrical stunning was correlated with unconsciousness a complementary laboratory study was performed. Here, carp were exposed to electrical current densities between 0.09 and 0.41 A/dm 2 . The presence of behavioural responses and visually-evoked responses (VER) in the electro-encephalogram in response to light flashes as indicators for an absence of consciousness was recorded., Results: The carp farms applied manual percussive (18%) or electrical (23%) stunning methods, while the majority of farms used a combination of electrical stunning immediately followed by manual percussive stunning (59%). In the latter condition, 92.6% of stunned carp displayed no behavioural indicators of consciousness and significantly fewer injuries related to mishits compared to sole percussive stunning. In the laboratory study, behavioural indicators of consciousness recovered in carp between 1 and 9 min following removal of the electrical current. However, VER could be recorded already at 30 ± 8 s post stunning. This indicates a fast recovery of carp from electrical stunning when exposed to current densities in the range of those generated by commercially available stunning instruments for fish., Conclusions: Under field conditions, percussion (applied manually) and electrical stunning might be poor inducers of unconsciousness before slaughter, while a combination was most effective. In order to undertake improvements in electrical stunning, further investigations into the current density, required for inducing prolonged insensibility in carp during electrical stunning, are needed.

1. The aim of this study was to evaluate the electroencephalographic (EEG) and behavioural responses of turkeys stunned with three different concussive non-penetrative captive-bolt guns prior to slaughter. 2. A total of 31 slaughter weight ex-breeding female turkeys (29 weeks of age; mean body weight 13.32 ± SD 0.65 kg) were stunned with the Cash Poultry Killer (CPK) (n = 10), Turkey Euthanasia Device (TED) (n = 10) and Zephyr EXL (n = 11). 3. Mean peak kinetic energy was highest for the CPK compared to the TED and Zephyr EXL (75.9 ± 4.5, 28.4 ± 0.4 and 24.4 ± 0.7 J, respectively). 4. A total of 29 (94%) of the turkeys were rendered unconscious following captive bolt stunning, with total power of the EEG (Ptot) significantly reduced from baseline values (reductions of 67% CPK, 84% TED and 76% Zephyr EXL, p < 0.01) and waveforms becoming isoelectric after periods of transitional EEG. However, two birds shot with the CPK and Zephyr EXL had periods of behavioural/reflexes (rhythmic respiration, nictitating membrane reflex, neck tension) and EEG activity (43-47 and 36-60 + s after the shot, respectively) indicating incomplete concussion and return of consciousness. In one bird, the shot was incorrectly positioned (Zephyr EXL), while the other appeared to be related to a defective cartridge (CPK). 5. In conclusion, all three captive bolt gun models were effective in producing unconsciousness in turkeys, provided they were positioned correctly and power loads performed according to their specifications.

Broilers in the United States are typically electrically stunned using low voltage-high frequency (12-38 V, ≥400 Hz) DC or AC water bath stunners. In the European Union, however, broilers are required to be electrocuted using high voltage-low frequency (50-150 V, 50-350 Hz) AC. Low voltage stunned broilers regain consciousness in the absence of bleeding. In contrast, high voltage stunned broilers die due to induction of cardiac fibrillation. For birds stunned with low voltage systems, concerns have been raised regarding animal welfare during bleeding. This work evaluated the impact of extended DC stunning duration and alternative stunning methods (DC+AC combination) on the recovery of bird consciousness and meat quality. In the absence of bleeding, broilers that were DC stunned for extended times (60, 90, or 120 s), 63, 10, or 0% of broilers, respectively, were able to recover consciousness. Alternative stunning protocols included water bath stunning broilers at 15 or 25 V DC for 10 s followed by plate stunning at 100, 110, or 120 V AC for 5 s. Prior to shackling, live body weight and shank width were measured and during stunning, maximum mA for both DC and AC stuns were recorded. All of the alternative stunning protocols (DC+AC) resulted in non-recoverable stunning. The maximum mA recorded during both DC and AC stunning were moderately/strongly (r = 0.54-0.81) correlated to body weight and poorly/moderately (r = 0.27-0.74) correlated to shank width. No significant differences for carcass or meat quality characteristics (hemorrhages, red wing tips, broken clavicles, pH, cook loss, a* and b* color values, and MORS shear energy) were detected between control (15 or 25 V DC only) and treatment groups (DC+AC combination stunning). The only significant different meat quality parameter was L* values where the lowest voltage group (15 V DC) had the darkest fillets (53.27) and the 15 V DC+100 V AC group had the lightest fillets (55.61) with all other groups intermediate. These data indicate that stunning parameters combining DC and AC stunning may be viable protocols when a stun-to-death is desired., (Published by Oxford University Press on behalf of Poultry Science Association 2017.)

Stunning prior to slaughter is commonly used to render the animal insensible to pain. However, for certain markets, stunning is disallowed, unless the animal can fully recover if not slaughtered. There are very few available methods of inducing a fully recoverable stun. This paper describes the development of a microwave energy application system for stunning cattle. Cadaver heads were used to demonstrate that brain temperature could be raised to a point at which insensibility would be expected to occur (44°C), and to calculate the power and time combinations required to achieve this in a range of cattle weights. Surface heating was identified as a cause for potential concern, which was mitigated by the development of another type of microwave applicator. Although the applicator and process variables require validation in animal studies, this technology shows promise as a method of inducing a recoverable stun., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

According to the Agreement on International Humane Trapping Standards (AIHTS), which was signed by the European Community, Canada, and Russia in 1997, killing devices used for the capture of canids and other fur-bearing nonhuman animals should render an animal irreversibly unconscious within 300 s. However, killing neck snares are not included in the agreement. In this commentary, a parallel is drawn between injuries caused by steel-jawed leghold traps, which have been banned by the AIHTS signatory countries, and killing neck snares to demonstrate that these snares should also be included in international humane trapping standards (i.e., AIHTS). Previous scientific investigations have shown that neither manual nor power-killing neck snares can consistently render canids unconscious rapidly. Animals caught in killing neck snares suffer injuries that are similar to or worse than those reported for leg-captured canids. The authors strongly recommend that AIHTS be modified to include killing neck snares and that such devices be subject to the criteria applied to other trapping devices. Alternative restraining trapping devices, which are effective and more humane, are available for capturing wild canids.

Animal welfare is receiving increasing attention from the authorities, the public and NGOs. For this reason, the improvement of animal welfare and animal handling systems is of the utmost importance for the meat industry. Technological developments have led to more animal friendly systems that handle animals on the day of slaughter, and these developments will be even more important as consideration for animal welfare and sustainability is no longer just a trend but a licence to operate. Improvement of animal welfare also leads to a higher value of the carcasses due to higher product quality, less cut-off caused by fewer injuries, and reduced working load, which leads to increased business opportunities. Therefore, good animal welfare is good business, and the development and implementation of new technology is the way to obtain improved animal welfare. These subjects will be addressed using examples and cases from the pork and broiler production industry., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Islam teaches zero-tolerance to all forms of animal abuse throughout the halal meat production supply chain and demands that when animals are slaughtered, they must be slaughtered in the mindful and attentive way espoused by the Prophet Muhammad. Why then are poor practices and animal welfare abuses still occurring during halal meat production, and how can they be reduced or eliminated? In this review we discuss how improvements might be achieved through: (1) training of staff regarding the religious and regulatory requirements of animal welfare from on-farm to slaughter; (2) empathy and compassion assessment of applicants prior to employment; (3) installation of CCTV cameras around lairage and slaughter sites; (4) regular employee follow-up training to minimise 'compassion fatigue'; (5) incorporating animal welfare requirements in halal certification; (6) using mosque-based sermons by Imams to increase awareness of animal welfare issues; and (7) making portable humane slaughter units available to small cottage operations and home/neighbourhood-kills through mosque-based organizations/structures., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Low atmospheric pressure stunning (LAPS) is a novel approach to poultry stunning involving the application of gradual decompression lasting 280 s according to a prescribed pressure curve. The aim of this study was to determine how behavioural, electroencephalogram (EEG) and electrocardiogram (ECG) responses to LAPS are influenced by illumination of the decompression chamber. A secondary aim was to examine responses to the decompression chamber without LAPS being applied, as such a "sham" control has been absent in previous studies. A two by two factorial design was employed, with LAPS/light, LAPS/dark, sham/light and sham/dark treatments (N = 20 per treatment). Broilers were exposed to each treatment in pairs, in each of which one bird was instrumented for recording EEG and ECG. Illumination was applied at 500 lx, and in sham treatments, birds were identically handled but remained undisturbed in the LAPS chamber without decompression for 280 s. Birds which underwent the sham treatment exhibited behaviours which were also observed in LAPS (e.g. sitting) while those exposed to LAPS exhibited hypoxia-related behaviours (e.g. ataxia, loss of posture). Behavioural latencies and durations were increased in the sham treatments, since the whole cycle time was available (in LAPS; birds were motionless by 186 s). Within the sham treatments, illumination increased active behaviour and darkness induced sleep, but slow-wave EEG was seen in both. The pattern of EEG response to LAPS (steep reduction in median frequency in the first 60 s and increased total power) was similar, irrespective of illumination, though birds in darkness had shorter latencies to loss of consciousness and isoelectric EEG. Cardiac responses to LAPS (pronounced bradycardia) closely matched those reported previously and were not affected by illumination. The effects of LAPS/sham treatment primarily reflected the presence/absence of hypoxia, while illumination affected activity/sleep levels in sham-treated birds and slowed time to unconsciousness in birds undergoing LAPS. Therefore, it is recommended that LAPS be conducted in darkness for poultry.

This second review describes indicators of consciousness and unconsciousness that can be used in the abattoir. These indicators evaluate different aspects of cerebral functioning, but only indirectly. It is therefore necessary to monitor several indicators. Animals are considered unconscious if signs of consciousness are absent, and signs of unconsciousness are present. Given that the unconscious state may be reversible it is further necessary to monitor these indicators until the end of bleeding. The techniques used to diagnose brain death in humans cannot be used in the slaughterhouse. Under field conditions, at the end of bleeding, the absence of breathing and of brainstem reflexes and the adequacy of the exsanguination are verified. If these three aspects are confirmed, in the context of the slaughterhouse and at this stage of the slaughter process the loss of vital functions is irreversible and the animal can be considered dead., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This review describes the neurobiological mechanisms that are relevant for the stunning and killing process of animals in the abattoir. The mechanisms underlying the loss of consciousness depend on the technique used: mechanical, electrical or gas stunning. Direct exsanguination (without prior stun) causes also a loss of consciousness before inducing death. The underlying mechanisms may involve cerebral anoxia or ischemia, or the depolarisation, acidification and/or the destruction of brain neurons. These effects may be caused by shock waves, electrical fields, the reduction or arrest of the cerebral blood circulation, increased levels of CO2 or low levels of O2 in the inhaled air, or the mechanical destruction of neurons. The targeted brain structures are the reticular formation, the ascending reticular activating system or thalamus, or the cerebral hemispheres in a general manner. Some of the techniques, when properly used, induce an immediate loss of consciousness; other techniques a progressive loss of consciousness., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The study assesses the effectiveness of reversible head-only and back-of-the-head electrical stunning of chickens using 130-950 mA per bird at 50 Hz AC. Three trials were conducted to compare both stunning systems: (a) behavioural assessment of return of consciousness, (b) insensibility to thermal pain, and (c) assessment of return of brain activity with visually evoked potentials (VEPs). Assessment of behaviour suggested that the period of unconsciousness following head-only electrical stunning was shorter in hens compared to broilers. Stunning across the back-of-the-head delayed the time to return of brainstem function compared to stunning with standard head-only electrodes. Additionally, back-of-the-head stunning produced a more prolonged period of electroanalgesia compared to head-only. Based on examination of return of brain function with VEPs in hens, back-of-the-head stunning produced a shorter-lasting stun than standard head-only. However, even for standard head-only, the stun was notably shorter than previously reported. In some birds, brain function had returned within 9 s after the end of stunning. The results suggest that some birds may recover consciousness prior to or during the neck cut. Based on these findings, back-of-the-head stunning and standard head-only stunning of hens should not be recommended without further development.

The effects of different amounts and frequencies of stunning sine wave alternating current were investigated under field conditions. Seven hundred and fifty broilers were stunned in an electrical water bath with an average root mean square (RMS) current of 150, 200, and 250 mA and frequencies of 200, 400, 600, 800, and 1,200 Hz. The occurrence of corneal reflex, spontaneous eye blinking, and a positive response to a painful stimulus were monitored and recorded immediately after the stunning and at 20 s post-stun. Statistical analysis showed that the electrical stunning frequency (P=0.0004), the stunning RMS current (P<0.0001) and the interaction between stunning frequency and stunning current (P<0.0001) had a significant effect on the occurrence of animals experiencing an abolition of corneal reflex at 20 s post-stun.At a current of 150 mA, the probability of a successful stun was over 90% at 200 Hz, approximately 40% at 400 Hz, and below 5% for frequencies greater than 600 Hz. So, stunning at frequencies greater than 600 Hz cannot be recommended when a RMS current of 150 mA is applied. The maximum probability of a successful stun was obtained for a current level of 200 mA at 400 Hz and for a current level of 250 mA at 400 and 600 Hz, whereas the stunning treatments at 1,200 Hz provided the lowest probability of a successful stun. Assessment of spontaneous eye blinking and responses to comb pinching confirmed the indications coming from the analysis of corneal reflex., (© 2016 Poultry Science Association Inc.)

This study examined the effect of neck cut position on the time to physical collapse in upright restrained halal slaughtered cattle (n = 644). Time to collapse was used as an indirect indicator of the early stages of onset of unconsciousness. Cattle were slaughtered with either a conventional low (LNC) (n=561) or a high neck cut (HNC) (n = 83). Mean time to final collapse was higher in the LNC compared to HNC group (18.9 ± 1.1s and 13.5 ± 1.3s respectively (P < 0.01)). The mean false aneurysm scores were higher in the LNC cattle (0.8 ± 0.0) compared to the HNC (0.6 ± 0.1) (P < 0.01). Animals that took > 20s to final collapse had larger false aneurysms. In summary, the HNC reduced the mean time to final collapse and the frequency of animals that took longer than 20s to collapse., (Copyright © 2015. Published by Elsevier Ltd.)

The validity of behavioural indicators to assess unconsciousness under different slaughter conditions is under (inter)national debate. The aim of this study was to validate eyelid-, withdrawal-, threat reflex and rhythmic breathing as indicators to assess unconsciousness in sheep. Sheep were monitored during repeated propofol anaesthesia (n=12) and during non-stunned slaughter (n=22). Changes in the EEG and behavioural indices of consciousness/unconsciousness were assessed and compared in sheep. Threat reflex and rhythmic breathing correlated with EEG activity during propofol anaesthesia whilst absence of non-rhythmic breathing or threat reflex indicated unconsciousness. None of the behavioural indicators correlated with EEG activity during non-stunned slaughter. Absence of regular breathing and eyelid reflex was observed 00:27±00:12 min and 00:59±00:17 min (mean±SD) respectively after animals were considered unconscious, indicating that absence of regular breathing and eyelid reflex are distinctly conservative indicators of unconsciousness during non-stunned slaughter in sheep., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Euthanasia of small numbers of birds in case of injury or other illness directly on the farm may be necessary for welfare reasons. This should be done without transportation of the moribund animals in order to minimize pain and distress. Blood loss has to be avoided to minimize the risk of contaminating the environment. Cervical dislocation in combination with a blunt trauma may be an appropriate way to achieve this aim but the bird's age and body weight may influence the practicability of this method in the field. In this study, we evaluated broilers, broiler breeders, and turkeys of different age groups and weights up to nearly 16 kg for the efficacy of blunt trauma to induce unconsciousness, allowing subsequent killing of the bird without pain. The effect of blunt trauma on the brain was determined by electroencephalography (EEG). Auditory evoked potentials (AEPs) were recorded for each animal. Convulsions or tonic seizures were observed in all investigated animals after blunt trauma, including strong wing movements, torticollis, and stretching of legs. The EEG results demonstrate that the blunt trauma induced by a single, sufficiently strong hit placed in the frontoparietal region of the head led to a reduction or loss of the AEP in all groups of birds. These results clearly indicate a loss of sensibility and induction of unconsciousness, which would allow painless killing of the birds immediately after the induction of the blunt trauma., (© 2015 Poultry Science Association Inc.)

Assessing unconsciousness is important to safeguard animal welfare shortly after stunning at the slaughter plant. Indicators that can be visually evaluated are most often used when assessing unconsciousness, as they can be easily applied in slaughter plants. These indicators include reflexes originating from the brain stem (e.g. eye reflexes) or from the spinal cord (e.g. pedal reflex) and behavioural indicators such as loss of posture, vocalisations and rhythmic breathing. When physically stunning an animal, for example, captive bolt, most important indicators looked at are posture, righting reflex, rhythmic breathing and the corneal or palpebral reflex that should all be absent if the animal is unconscious. Spinal reflexes are difficult as a measure of unconsciousness with this type of stunning, as they may occur more vigorous. For stunning methods that do not physically destroy the brain, for example, electrical and gas stunning, most important indicators looked at are posture, righting reflex, natural blinking response, rhythmic breathing, vocalisations and focused eye movement that should all be absent if the animal is unconscious. Brain stem reflexes such as the cornea reflex are difficult as measures of unconsciousness in electrically stunned animals, as they may reflect residual brain stem activity and not necessarily consciousness. Under commercial conditions, none of the indicators mentioned above should be used as a single indicator to determine unconsciousness after stunning. Multiple indicators should be used to determine unconsciousness and sufficient time should be left for the animal to die following exsanguination before starting invasive dressing procedures such as scalding or skinning. The recording and subsequent assessment of brain activity, as presented in an electroencephalogram (EEG), is considered the most objective way to assess unconsciousness compared with reflexes and behavioural indicators, but is only applied in experimental set-ups. Studies performed in an experimental set-up have often looked at either the EEG or reflexes and behavioural indicators and there is a scarcity of studies that correlate these different readout parameters. It is recommended to study these correlations in more detail to investigate the validity of reflexes and behavioural indicators and to accurately determine the point in time at which the animal loses consciousness.

Impaired states of consciousness can be relatively easily identified, although it can occasionally be difficult to assess whether there is a pure disorder of wakefulness or awareness. Regardless, such impairments represent dysfunction of the brainstem and or cerebrum. Acute and severe impairments of consciousness can require immediate assessment, in part currently performed using the modified Glasgow coma scoring system, and emergency stabilization. The prognosis is always guarded and highly sensitive to the underlying etiology., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The objective of the present study was to determine the impact of recovering consciousness on physiological responses in hogs stunned with different concentrations of CO2. A total of 1336 pigs were moved into a CO2 anaesthesia chamber for 90s. The remaining pigs were assigned to 3 groups according to the CO2 concentration used for stunning: 85, 90 or 95%. Each group was then further divided into 2 sub-groups: those exsanguinated during the first 60s after leaving the chamber without recovering consciousness (WRC); and those exsanguinated after more than 60s that recovered consciousness (RC). The blood pH of the RC pigs decreased below 7.08, but their blood levels of Ca(2+) (>1.59mmol/L), glucose (>159.79mg/dL), and lactate (>103.52mg/dL) all increased when compared to reference values (RV) (P<0.05). Therefore, a greater metabolic and energy imbalance occurs during exsanguination when pigs recover consciousness. In conclusion, exsanguination should be performed immediately upon the pigs leaving the CO2 chamber., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Two experiments were conducted to evaluate a new electrical stunning system for broilers. The objective of the first experiment was to evaluate the behavioral, neural, and physiological responses of 27 broilers after head-only electrical stunning while their bodies were restrained in cone-shaped holders. In the second experiment, quality of meat from 30 broilers after head-only electrical stunning in a cone-shaped restrainer was compared with that from 30 broilers stunned in a conventional water bath. Broilers were restrained in the cone with their heads positioned to facilitate a correct stun, followed by a neck cut by hand. After stunning, each broiler displayed a tonic phase, followed by minimal brain activity during bleeding. On average, heart rate was 258 ± 51 beats/min before stunning. The heart was observed to malfunction after cutting. According to the correlation dimension analyses, the score remained low. Within a confidence limit of 95%, taking into account the number of birds with a reliable electroencephalogram (n = 27), the chance of an effective stun and exsanguination with all broilers lies between 0.90 and 1.00 using a sinusoidal AC current of 264 ± 29 mA (∼130 V). After a brief learning period, operators were able to easily position the broilers in the cone in a commercial setting. The pH after chilling was 0.5 units lower (P < 0.05) in the head-only stunned group compared with the group stunned in a conventional water bath. After head-only stunning, 60% of breast fillets showed no blood splashes and 3% showed severe blood splashes compared with 20 and 27% after conventional water bath stunning. No differences in temperature and color were observed between the 2 groups. It is concluded that broilers could be restrained in a cone, followed by correct head-only stunning, neck-cutting, and unconscious shackling afterward under laboratory and commercial slaughterhouse conditions. When this procedure was used, meat quality was better compared with broilers stunned in the conventional water bath.

We present results from the development of a new system of reversible electrical stunning of cattle. A single-pulse ultra-high current (SPUC) was generated from a capacitance discharge current spike of at least 5000 V at 70 A, for approximately 50 ms. Ninety-seven cattle were stunned in three experimental protocols. With improvements made to the design of the stun box and charge delivered, 38 cattle were either stunned and immediately jugulated or monitored for signs of reappearance of brain stem reflexes at which point a concussion stun was administered. This use of the SPUC charge, provided as a biphasic-pulse waveform, resulted in a high level of stunning efficacy, with unconsciousness lasting for up to 4 min. These results were supported by EEG data taken from a subsequent cohort of stunned cattle. The SPUC stun also apparently eliminated post-stun grand mal seizures that can occur following short-acting conventional electrical stun, with its associated negative consequences on operator safety and meat quality., (© 2013.)

The transformation of an animal into pieces fit for human consumption is a very important operation. Rather than argue about halal slaughter without stunning being inhumane or stunning being controversial from the Islamic point of view, we discuss slaughter, stunning and animal welfare considering both Islamic and animal welfare legislation requirements. With the world Muslim population close to two billion, the provision of halal meat for the Muslim community is important both ethically and economically. However, from the animal welfare standard point of view, a number of issues have been raised about halal slaughter without stunning, particularly, about stressful methods of restraint and the latency of the onset of unconsciousness. This paper sets out to, discuss the methods of stunning that are acceptable by Islamic authorities, highlight the requirements for stunning to be acceptable in Islam and suggest practical ways to improve the humanness of slaughter., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Disease control measures require poultry to be killed on farms to minimize the risk of disease being transmitted to other poultry and, in some cases, to protect public health. We assessed the welfare implications for poultry of the use of high-expansion gas-filled foam as a potentially humane, emergency killing method. In laboratory trials, broiler chickens, adult laying hens, ducks, and turkeys were exposed to air-, N2-, or CO2-filled high expansion foam (expansion ratio 300:1) under standardized conditions. Birds were equipped with sensors to measure cardiac and brain activity, and measurements of oxygen concentration in the foam were carried out. Initial behavioral responses to foam were not pronounced but included headshakes and brief bouts of wing flapping. Both N2- and CO2-filled foam rapidly induced ataxia/loss of posture and vigorous wing flapping in all species, characteristic of anoxic death. Immersion in air-filled, high expansion foam had little effect on physiology or behavior. Physiological responses to both N2- and CO2-filled foam were characterized by a pronounced bradyarrythymia and a series of consistent changes in the appearance of the electroencephalogram. These were used to determine an unequivocal time to loss of consciousness in relation to submersion. Mean time to loss of consciousness was 30 s in hens and 18 s in broilers exposed to N2-filled foam, and 16 s in broilers, 1 s in ducks, and 15 s in turkeys exposed to CO2-filled foam. Euthanasia achieved with anoxic foam was particularly rapid, which is explained by the very low oxygen concentrations (below 1%) inside the foam. Physiological observations and postmortem examination showed that the mode of action of high expansion, gas-filled foam is anoxia, not occlusion of the airway. These trials provide proof-of-principle that submersion in gas-filled, high expansion foam provides a rapid and highly effective method of euthanasia, which may have potential to provide humane emergency killing or routine depopulation.

In low atmospheric pressure stunning (LAPS), poultry are rendered unconscious before slaughter by gradually reducing oxygen tension in the atmosphere to achieve a progressive anoxia. The effects of LAPS are not instantaneous, so there are legitimate welfare concerns around the experience of birds before loss of consciousness. Using self-contained telemetry logging units, high-quality continuous electroencephalogram (EEG) and electrocardiogram (EKG) recordings were obtained from 28 broiler chickens during exposure to LAPS in a commercial poultry processing plant. Application of LAPS was associated with changes in the EEG pattern in the form of increases in total power, decreases in mean frequency, and in particular, increases in slow-wave (delta) activity, indicating a gradual loss of consciousness. Increased delta wave activity was seen within 10 s of LAPS onset and consistently thereafter, peaking at 30 s into LAPS at which point the EEG signal shared characteristics with that of birds in a surgical plane of anesthesia. During LAPS, heart rate consistently decreased, with more pronounced bradycardia and arrhythmia observed after 30 s. No heart rate increases were observed in the period when the birds were potentially conscious. After an initial quiescent period, brief body movements (presumed to be ataxia/loss of posture) were seen on average at 39 s into the LAPS process. Later (after 120 s on average), artifacts related to clonic (wing flapping) and tonic (muscle spasms) convulsions were observed in the EKG recordings. Based on EEG analysis and body movement responses, a conservative estimate of time to loss of consciousness is approximately 40 s. The lack of behavioral responses indicating aversion or escape and absence of heart rate elevation in the conscious period strongly suggest that birds do not find LAPS induction distressing. Collectively, the results suggest that LAPS is a humane approach that has the potential to improve the welfare of poultry at slaughter by gradually inducing unconsciousness without distress, eliminating live shackling and ensuring every bird is adequately stunned before exansguination.

In two pig abattoirs of different slaughter capacities, the stunning efficacy of CO2 on finishing pigs with and without pneumonic lesions (observed post mortem) was reflected against the corneal-reflex and blood parameters (blood pH, pCO2 and pO2) from individual finishers. Stunning duration was 120 s (abattoir A) and 90 s (abattoir B), respectively. Pneumonia in finisher pigs is frequently observed during post mortem inspection, which may raise concerns about a delay of unconsciousness because of hampered gas exchange in the lungs. The aim of this study was to examine possible pneumonia consequences for stunning efficacy under commercial conditions. For that, corneal reflex, O2 and CO2 partial pressure in the blood as well as blood pH were measured in 2650 finishers from abattoir A and 2100 from abattoir B. The partial pressure of O2 after stunning accounted to about 3 kPa, the partial pressure of CO2 was found at levels of about 24 kPa in abattoir A (after 120 s CO2 exposure) and 17.5 kPa in abattoir B (after 90 s CO2 exposure). In abattoir A, the blood pH was at 6.9, and at 7.0 in abattoir B. The corneal reflex was observed in 6.2% of pigs in abattoir A and 17.1% of pigs in abattoir B. A correlation between pneumonic lesions and blood status was not observed. However, for some individual farms, a significant correlation between pneumonia and corneal reflex was observed., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

In two cattle head deboning plants, a total of 8879 cattle skulls were investigated for number and precision of shots. Deviation from the ideal position on the forehead and the direction of the shot were measured, results were then attributed to three classes of precision. In all, 64.7% of the skulls in plant 1 and 65.3% in plant 2 were shot from the ideal position and in the ideal direction. A medium precision was observed in 31.3% and 31.5% of cases, 4.0% and 3.1%, respectively, of the skulls indicated a poor precision. In both plants, skulls with more than one shot hole were observed. Shot holes may indicate the precision of a shot, and thus the risk of suffering during the sensitive time of stunning. In addition to observations at the time of stunning, the observation of shot holes on skulls at random or in total after a day's slaughter can reflect the shooting precision.

Stunning effectiveness of male and female broiler chickens was analyzed in response to different waveforms at 3 constant voltage levels. In total, 180 male and female broiler chickens were stunned using a sine wave alternating current (AC) of 50 Hz, rectangular AC of 70 Hz, and pulsed direct current (DC) of 70 Hz (duty-cycle 1:1) with a constant voltage of 60, 80, or 120 V, respectively. In each stunning group, 10 male and 10 female birds were stunned for 4 s. The current obtained by every bird was recorded. For stunning efficiency, the electroencephalogram (EEG) and physical reflexes were recorded and analyzed. The EEG was recorded for 120 s poststun. Simultaneously, the occurrence of spontaneous eye blinking, wing flapping, and breathing was assessed, and the corneal reflex was tested every 20 s poststun. The EEG was analyzed regarding the occurrence of a profound suppression to less than 10% of the prestun level in the 2 to 30 Hz and 13 to 30 Hz bands. Female broilers obtained a significantly lower stunning current compared with that of the males. This resulted in a lower stunning efficiency for females, when the same constant voltage was applied to males and females. The waveforms required different amounts of currents to achieve a 90% stunning efficiency. A minimum necessary stunning current of 70, 90, and 130 mA could be established for sine wave AC, rectangular AC, and pulsed DC, respectively. The low stunning efficiency of pulsed DC might be caused by the short stunning time of 4 s. This effect should be further investigated for DC stunning. Very few birds stunned with AC resumed breathing following stunning, indicating stun to kill. Pulsed DC stunning showed a lower effect on the induction of death. The level of wing flapping, indicating convulsions and possible meat quality defects, was higher for the AC treatments.

This study aimed to investigate the effects of different CO(2) concentrations on blood variables, glycolytic potential (GP), and meat quality of hot-boned muscles in broilers. Thirty broilers were exposed to one of the following 5 gas mixtures for 90 s: 40% CO(2) + 30% O(2) + N(2) (control), 30% CO(2) + 21% O(2) + N(2) (G30%), 40% CO(2) + 21% O(2) + N(2) (G40%), 50% CO(2) + 21% O(2) + N(2) (G50%), and 60% CO(2) + 21% O(2) + N(2) (G60%). Samples were taken from the pectoralis major (PM), musculus iliofibularis (MI), and tibialis anterior muscles 45 min postmortem. The ultimate pH in both the PM (vs. G30% and G40%) and MI (vs. G40%) was decreased with G60% (P < 0.05), whereas drip loss in the PM (vs. G30%, P = 0.01) was increased with G60%. Drip loss in the MI (vs. control and G30%, P < 0.01) was increased with G50%. Lightness after 24 h in PM (vs. G30% and G40%, P < 0.01) was increased with G50%. In MI, lightness after 24 h was slightly decreased with G40% compared with the control (P < 0.10). The GP value in the PM was lower in the G30% and G40% than in G60% (P < 0.05), and the GP value in the tibialis anterior was the lowest in G30% (P < 0.01). Plasma corticosterone, plasma glucose, and meat quality (pH, lightness, redness, yellowness) 45 min postmortem were not affected by CO(2) levels (P > 0.05). In conclusion, stunning broilers with low CO(2) levels (30 and 40%) improved meat quality but had no advantage in animal welfare compared with high CO(2) levels (50 and 60%).

Behavioral and neural responses of 47 broilers to head-only single-bird electrical stunning were evaluated using cone-shaped restrainers in which the broilers were suspended by their feet. Meat quality assessment was performed on 2 groups of 25 broilers stunned using the head-only method or a conventional water bath method. Hemorrhages were quantified by a visual grading system. On electroencephalogram recordings, a general epileptiform insult was observed when a set current of at least 190 mA (~100 V, 50 Hz) was applied for a duration of 0.5, 3, or 5 s. This insult showed a tonic phase, followed by a clonic phase and an exhaustion phase, after which the birds recovered. On the basis of visual observation, these birds may have been unconscious for approximately 30, 44, or 65 s. According to correlation dimension analysis scores, these durations were 18, 12, and 16 s, respectively. Within a confidence limit of 95%, taking into account the number of birds with a reliable electroencephalogram, the chance of an effective stun lies between 0.95 and 1.00 with an average current of 190 ± 30 mA. After stunning, the electrocardiogram revealed fibrillation. The heart rate decreased significantly (P < 0.05) after stunning but recovered thereafter. The pH after chilling was (P < 0.05) lower in the group stunned head only compared with the water bath group. The percentages of fillets free of blood splashes were 80% in carcasses of head-only-stunned birds and 16% in carcasses from broilers stunned in the commercial water bath. It was concluded that broilers were insensible and unconscious after head-only electrical stunning using pin-electrodes. Because of the risk that broilers can rapidly regain consciousness after stunning, cutting the neck immediately after stunning is recommended. It is also recommended that the head-only equipment be developed further for practical application and commercial use.

Four groups of Manchega breed suckling lambs, stunned with different CO(2) concentrations and exposure times (G1: 80% CO(2) 90s; G2: 90% CO(2) 90s; G3: 90% CO(2) 60s; G4: 80% CO(2) 60s) plus an electrically stunned control group (G5), were used to determine (1) the physiological responses (hormonal, haematological and biochemical blood parameters) of animals after stunning and (2) the stunning effectiveness in each group. No significant differences were found among groups for hormonal levels. Within haematological parameters, significant differences among groups were only found for haemoglobin (P<0.05) and leucocytes (P<0.01), with lowest values in both groups stunned with 90% CO(2). There were significant differences between groups (P<0.01) for urea and total protein, creatinine and LDH (P<0.05; lowest and highest, respectively, for G1) and for sodium (P<0.001; lowest in G3). Stunning effectiveness was highest in G5, G3 and G1 groups and lowest in G2 and G4 (100%, 90%, 89%, 50% and 43%, respectively). According to discriminant analysis, sodium, leucocytes and creatinine marked the differences among stunning groups., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Commercial slaughter of farm livestock usually employs an extensive incision that severs the soft tissues of the neck including the major blood vessels supplying and draining the brain. It is intended to cause a catastrophic decrease in cerebral blood flow with rapid onset of unconsciousness or insensibility. The tissues of the neck are innervated with nociceptive nerve fibres and their transection will cause a barrage of sensory impulses. Consciousness, and therefore the ability of the animal to feel pain and experience distress after the incision, may persist for 60 seconds or longer in cattle. These observations suggest that livestock may experience pain and distress during the period before they become unconscious (insensible). Psychological shock and fear may also be associated with the extensive tissue damage and blood loss. Pre-incision stunning has been adopted as a precautionary measure to prevent suffering. However, the question remains: How intense and noxious are these experiences? Recent methodological developments related to quantitative analysis of the electroencephalogram (EEG) allow the experience of pain to be assessed more directly than has hitherto been possible. This methodology has now been applied to the question of the slaughter of calves by ventral-neck incision. The new information demonstrates clearly for the first time that the act of slaughter by ventral-neck incision is associated with noxious stimulation that would be expected to be perceived as painful in the period between the incision and loss of consciousness. These data provide further support for the value of stunning in preventing pain and distress in animals subjected to this procedure.

Ever since the middle of the nineteen-eighties electrical stunning of cattle is used in industrial slaughter plants in New Zealand. Today electrical stun boxes operate in export slaughter plants throughout New Zealand. The reversible stun is utilised on the vast majority of slaughtered cattle. The electrical stunning (head only) immediately followed by bleeding is an alternative to ritual slaughter without prior stunning. Throughout the world's islamic community this alternative is widely accepted as Halal.