Non-penetrating Captive Bolt Research Articles

15 Experiences with Swine Depopulation

Abstract The COVID-19 pandemic created a crisis situation for US swine producers. Unexpected and prolonged closure of numerous harvest facilities created a backlog of market ready pigs. The “just in time” nature of our industry proved fragile under these circumstances and numerous farms needed to rapidly depopulate swine of various ages. While these experiences were painful, they did create a series of “lessons learned” that can be applied to future depopulation scenarios. Some of the major considerations for depopulation methods include the facility location, procedures to perform the depopulation and disposal of the depopulated carcasses. With many pig farms being home to thousands of animals, the need to perform depopulation in a high-speed and highly effective manner is an absolute requirement. Guiding principles for depopulation have been developed by the American Veterinary Medical Association (AVMA) and these guidelines serve as a starting point for understanding what options are available to producers facing depopulation as well as which option may be most practical for a specific situation. Common depopulation strategies employed on farm include gas inhalation with carbon dioxide or carbon monoxide, electrocution, penetrating or non-penetrating captive bolt and ventilation shutdown plus (VSD+). Each strategy requires unique levels of equipment, skill, technical expertise, labor, time and cost. Common carcass disposal strategies include composting, landfill, rendering and burial. It is impossible to define a specific depopulation and disposal strategy that is optimal for every site however a thorough understanding of the characteristics of each option allows producers to determine the optimal process for their specific situation. Considerations for optimal strategies must incorporate consideration for practicality, speed of depopulation and disposal, animal well-being, human safety and human well-being.

History and best practices of captive bolt euthanasia for swine.

The definition of animal welfare includes how an animal dies. As such, euthanasia is intrinsically linked to animal welfare, and ensuring a good death through effective, safe, and validated practices is a critical piece of promoting positive animal welfare. The objective of this review is to provide a better understanding of the literature on the euthanasia of swine via penetrating captive bolt (PCB) and nonpenetrating captive bolt (NPCB), as well as a history of captive bolt use, and indicators of sensibility and insensibility. To do this, we performed a systematic review that included 30 peer-reviewed articles and 17 other publications. NPCB devices have been validated as an effective single-step euthanasia method for neonatal and preweaning swine, as well as a two-step euthanasia method for nursery swine. PCB devices have been validated as an effective euthanasia method for nursery and market swine up to 120 kg, but further investigation is required for the use of captive bolt devices on mature breeding sows and boars.

Assessing the effect of water deprivation on the efficacy of on-farm euthanasia methods for broiler chickens

ABSTRACT 1. Moribund or diseased poultry requiring euthanasia are often dehydrated. To understand how dehydration influences the efficacy of various killing methods, this experiment investigated the effect of water deprivation (WD) on times to unconsciousness and death. 2. Broiler chickens (n = 179) were water-deprived for 0, 24, 48 or 72 hours to mimic dehydration, then killed via manual cervical dislocation, mechanical cervical dislocation (Koechner Euthanising Device (KED)), or non-penetrating captive bolt (Zephyr-EXL), at 8, 22, 36 or 50 d of age. Degree of WD was confirmed by skin turgor, packed cell volume and body weight loss. Method efficacy was evaluated by the time to unconsciousness and death using pupillary light (PUP), palpebral blink (PAL) and nictitating membrane (NIC) reflexes, feather erection (FE), cloacal winking (CW) and convulsions (CN). The extent of damage caused by each method was examined via radiography, gross pathology and histopathology. The main effects of WD time and euthanasia method were analysed by two-way analyses of variance (CRD, PROC MIXED, SAS 9.4) with a-priori contrasts to compare water-deprived versus non-water-deprived (NON) birds. 3. Skin turgor, packed cell volume and body weight loss had a quadratic relationship with WD, with highest values for those birds which were water-deprived for 72 h. WD level did not affect time to unconsciousness. Time to death was longer for WD birds than NON, with longer latencies to FE, CW and CN for water-deprived birds. WD only affected radiography or gross pathology scores on d 8, with the extent of subcutaneous haemorrhage within the neck decreasing as WD increased. 4. The shortest latency to PUP loss, at all ages, and to PAL and NIC loss, at 22 d, was with the Zephyr-EXL. KED had the longest time to unconsciousness (PUP, PAL and NIC), at all ages, and to death, at 36 and 50 d. 5. Overall, WD increased time to death, but did not affect the onset of unconsciousness, with no interaction between methods and WD level.

Effect of Electrical and Mechanical Stunning on Rabbit Meat Quality Traits

Abstract Increased interest in the production of rabbit meat justifies the need to assess and improve the welfare of these animals not only during the production cycle but also at slaughter. Therefore, the aim of this study was to assess the effects of different stunning methods on the level of blood biochemical parameters (stress indicators), and meat quality of slaughter rabbits. Rabbits of the Hycole line (n = 60) were subjected to the following stunning methods: mechanical with a non-penetrating captive bolt (group I; n = 20), mechanical by hitting a narrow rod on the head (group II; n = 20), and electrical stunning (n = 20). In the stunning groups there were no differences found in the blood level of insulin, cortisol, glucose, total cholesterol, triglycerides, non-esterified fatty acids, and protein content (P>0.05). The stunning method did not affect the pH of rabbit meat (P=0.768), but significantly influenced the L* and b* colour parameters. The muscles of longissimus thoracis et lumborum, from the group of rabbits mechanically stunned by hitting a narrow rod on the head, were the darkest (L * = 58.4), with the lowest yellowness values (b* = 4.04). The meat of electrically stunned rabbits was characterised by higher drip loss (P<0.001), lower plasticity (P=0.043), and higher free water content (P=0.043). From the analysed texture measures, only the Warner Bratzler Shear Energy values of the cooked meat were affected by the stunning method. These values were higher in the meat of the mechanically stunned groups compared to the electrically stunned rabbits (P=0.042). The percentage of dry matter, crude protein, extractable fat and water to protein ratio, were affected only by the muscle type (P<0.001). To conclude, the rabbit meat was characterised by good quality, with only slight differences between the groups. No differences were found in the stress reaction of rabbits subjected to the examined stunning methods.

Comparison of penetrating and non-penetrating captive bolt in an alternative occipital approach in calves

AbstractThe objective of this study was to describe the effect of penetrating or non-penetrating captive bolt using an occipital approach in 4-5 month old, Holstein steers weighing between 100-200 kg. Twelve calves were divided into two treatment groups; penetrating captive bolt (PCB; n = 6) and non-penetrating captive bolt (NPCB; n = 6). This sample size was chosen out of convenience and in conjunction with a separate study. Each calf was sedated with xylazine hydrochloride, then a captive-bolt device, outfitted with a standard penetrating bolt or a non-penetrating bolt, was placed flush on the dorsal midline of the cranium at the external occipital protuberance and aimed downward as though to intersect the intermandibular area. Following impact, indicators for loss of consciousness, such as respiration, righting response, corneal reflex, movement and vocalisation were recorded and characterised along with electrocardiogram and electroencephalogram recordings. After a 5-min observation period, all calves were administered potassium chloride. All calves experienced immediate and sustained loss of consciousness. The mean (± SEM) time to cessation of respiration was 60 (± 53.67) and 0 (± 0.0) s for PCB and NPCB, respectively. The mean time to cessation of convulsions was 310.4 (± 79.74) and 180.0 (± 60.24) s, respectively, and the mean number of convulsions was 2.75 (± 1.03) and 2.0 (± 0.837) for PCB and NPCB, respectively. Isoelectric EEG patterns were observed in 3/5 PCB and 3/4 NPCB with mean time to onset of isoelectric pattern in 69.0 (±52.24) and 113.5 (± 56.87) s. Both treatments induced a successful stun, which suggests these techniques are appropriate for humane euthanasia in calves of this age.

Anatomical Pathology, Behavioral, and Physiological Responses Induced by Application of Non-penetrating Captive Bolt Devices in Layer Chickens.

We evaluated three models of non-penetrating captive bolt devices, Zephyr-E, Zephyr- EXL, and Turkey euthanasia device (TED) for time to loss of sensibility and degree of brain damage during euthanasia in four age groups of male and female layer chickens (10–11, 20–21, 30–35, 60–70 weeks respectively). Latencies to onset of insensibility and cardiac arrest were assessed to detect whether killing birds via these devices was humane and effective. Both gross and microscopic pathology evaluations were conducted to score skull and brain trauma post mortem. All three NPCB devices induced loss of breathing, pupillary reflex and nictitating membrane reflex within 5 s after application in most chickens. Latencies to loss of jaw tone and neck muscle tone were longer in 60–70 weeks old roosters (p < 0.05). Younger birds (10–21 week-old) demonstrated the longest time (p < 0.0001) to onset of tonic convulsions, time at last movement, cloacal relaxation and cessation of heart beat. A positive correlation (p < 0.0001) was found for all three devices between time of cardiac arrest and times to onset of tonic convulsions, last movement, and cloacal relaxation. More than 80% of birds had skin lacerations with external bleeding following application of all 3 devices. Device type did not affect the incidence of skull fractures but higher skull fracture scores were noted in 10–11 week-old birds compared to other ages. Regardless of device type and age, microscopic SDH was most apparent in the brain and proximal spinal cord of all birds. In summary, all three devices caused significant trauma to the midbrain and spinal cord. Results demonstrated that all three devices induce rapid insensibility after application and can be used as a single-step method that results in a humane death in all age groups of layer chickens.

Electroencephalographic assessment of pneumatically powered penetrating and non-penetrating captive-bolt stunning of bulls

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.

Humane euthanasia of neonates II: field study of the effectiveness of the Zephyr EXL non-penetrating captive-bolt system for euthanasia of newborn piglets

AbstractA previous study demonstrated the effectiveness of the Bock Industries Zephyr EXL non-penetrating captive bolt, using the abolition of visual-evoked potentials as a determination of brain death, in piglets in a laboratory. A second trial, reported here, involved the field-testing of this device, on-farm, in a commercial setting. Two hundred and seven piglets (mean [± SEM] dead weight: 1.86 [± 0.74] kg) requiring dispatch under the farm's protocols were euthanased with the device and demonstrated immediate loss of consciousness, subjectively assessed by behavioural signs and no recovery. Post mortem examination of the heads was undertaken confirming massive traumatic damage to the cerebrum with associated haemorrhage and bone plate shards forced down to the level of the corpus callosum in the majority of cases. A further trial of 106 piglets demonstrated that under commercial production conditions it took less than 7 s to select, place and euthanase a piglet using the device. One hundred percent of animals in the study were immediately killed. Given this complete kill rate and the sample size of the study, a statistical 95% confidence interval provides a maximum percentage of animals that would not immediately be stunned/killed, by this mechanical non-penetrating captive-bolt system, to be at most 1.2% and at least 0%. The results here, combined with the previous study, allow recommendation of the Bock Industries Zephyr EXL as being suitable as a single application euthanasia device for piglets up to 10.9 kg liveweight.

Use of a Non-Penetrating Captive Bolt for Euthanasia of Neonate Goats

Simple SummaryWith animal production systems, there is an inevitable need for the stock person to humanely kill new-born (neonate) animals, either due to disease, malformation, or in instances of production efficiency (males born to a milking herd for example). At present, the standard method employed is manual killing with a blunt object or swinging the animal so that its’ head contacts a hard surface such as a wall. Stockpeople do not like performing this action and it also has consequences for the animal in terms of reproducibility and ability of the stockperson. This study examines the use of a mechanical captive bolt device to produce immediate brain death in neonate goats, causing this state of irreversible brain dysfunction before the animal can feel the procedure, or the effects of the procedure. This study found that a device powered by a blank cartridge, containing a specified amount of explosive (1 grain), when applied in a specific position on the head produced immediate brain death in neonate goats. As such, this method is considered to be a reproducible and humane method of euthanasia, as the brain is destroyed before the animal can feel the shot.A non-penetrating captive bolt device, powered by a 1 grain 0.22″ cartridge delivering a calculated kinetic energy of 47 Joules was tested as a euthanasia method on 200 neonate goats (Capra aegagrus hircus) of mean dead weight = 4.425 kg (SD (Standard deviation) ± 0.4632), to assess effectiveness and shot position. Evaluation of the method was conducted using behavioural indicators of brain dysfunction followed by post mortem examination of the heads. Once correct shot position had been established, 100% of 158 kids (95% confidence interval 97.5% to 100%) were successfully stunned/killed with a shot positioned on the midline, between the ears, with the chin tucked into the neck. The use of the Accles and Shelvoke CASH Small Animal Tool can therefore be recommended for the euthanasia of neonate goats with a 1 grain cartridge and a specific shooting position.

The Use of a Non-Penetrating Captive Bolt for the Euthanasia of Neonate Piglets.

Simple SummaryThe humane destruction of newborn piglets (neonates), when required, is an issue faced by farmers and producers. The application of blunt force trauma, either through swinging the animal against a wall, or hitting it with a weighted object, is a stressful procedure for the stock person and has implications for the animal in terms of welfare, instantaneous effect and reproducibility. The United Kingdom government funded this project to find a single application method that could be used on farms that would produce an immediate kill with these animals. This project demonstrates that the use of a mechanical captive bolt device, that does not enter the head, delivers sufficient energy when applied to the head of a piglet to immediately destroy the brain leading to the death of the animal. This method will improve animal welfare on farms, as well as providing producers with a device that they can be confident will kill the animal without pain, as the brain is destroyed before the animal can perceive a pain nerve impulse.The most common method for the on-farm euthanasia of neonate piglets is reported to be manual blunt force trauma. This paper presents the results of research to evaluate a mechanical non-penetrating captive bolt (the Accles and Shelvoke CASH small animal tool, Birmingham, UK) to produce an immediate stun/kill with neonate piglets. One hundred and forty-seven piglets (average dead weight = 1.20 kg ± 0.58 (standard deviation, SD), mean age = 5.8 days (median = 3)) were euthanized with the device and demonstrated immediate loss of consciousness, subjectively assessed by behavioural signs and no recovery. The result that 147 out of 147 animals were effectively stun/killed gives a 95% confidence interval for the true percentage of animals that would be effectively stun/killed of 97.5–100% with the use of the CASH small animal tool under the conditions of the current study. This research concludes that the CASH small animal tool, using a 1 grain brown coded cartridge, is suitable for producing a stun/kill in neonate piglets when applied in a frontal/parietal position.

The Use of a Mechanical Non-Penetrating Captive Bolt Device for the Euthanasia of Neonate Lambs.

Simple SummaryNo stockperson or producer of lamb wants or likes to euthanase their young animals (neonates). At present, there are few reliable methods of achieving a humane dispatch of a neonate lamb should it be required. In the United Kingdom, the main method used in these cases is manually impacting the head by swinging the animal against a hard surface or hitting the animal with a hard object such as a hammer. This paper examines the use of a blank cartridge powered device to stun-kill neonate lambs immediately (i.e., before the animal can feel the application). Using this method, a suitable application point and power of cartridge has been determined, providing the stockperson with a reliable and repeatable single application method for euthanasing young lambs without the animal feeling any pain, as the device produces brain death faster than the nerve impulse can travel to the brain. This will improve animal welfare on-farm in these circumstances.A non-penetrating captive bolt device, powered by a 1-grain 0.22″ cartridge delivering a calculated kinetic energy of 47 Joules was tested as a euthanasia method on 200 neonate lambs (Ovis aries) of 4.464 kg (SD (Standard deviation) ± 1.056) mean dead weight, to assess effectiveness and shot position. Every lamb (n = 200) was effectively stunned when the weapon was applied powered by a brown, 1-grain cartridge but 10/200 (5%) of the lambs displayed rhythmic or agonal breathing and were subsequently euthanased using euthatal (Merial, UK, GTIN: 03661103015550). Evaluation of the method was conducted using behavioural indicators of brain dysfunction followed by post-mortem examination of the heads. A second trial was conducted using a higher velocity 1.25-grain cartridge and a specific shot position on 48 lambs (mean dead weight = 6.21 kg, SD ± 1.24) averaging 5 days old. One hundred percent of the lambs in the second trial were immediately stun-killed. Given this complete kill rate and the sample size of the study, the study provides a statistical 95% confidence interval of 92.6% to 100%. The use of the Accles & Shelvoke “CASH” Small Animal Tool (Birmingham, UK) can therefore be recommended for the euthanasia of neonate lambs with a 1.25-grain cartridge and a specific shooting position.

Evaluation of Two Models of Non-Penetrating Captive Bolt Devices for On-Farm Euthanasia of Turkeys

Simple SummaryAnimal care guidelines for livestock and poultry require farms to have euthanasia plans in place for birds that are sick, injured, or unable to access feed and water. Killing methods considered to be humane are those that induce rapid insensibility (stun) and result in brain death leading to irreversible respiratory and cardiac arrest. Therefore, the evaluation of the effectiveness of a killing method generally focuses on measures of insensibility and brain death. Non-penetrating captive bolt devices are intended to deliver sufficient force and energy to the head to result in immediate insensibility and brain death without penetrating the skin. We evaluated the effectiveness of two models of non-penetrating captive bolt devices when applied by stock people to different sizes and ages of turkeys, using signs of insensibility corroborated by ante- and post- mortem evaluation of brain damage. Both non-penetrating captive bolt devices used in this study were found to be highly effective at inducing immediate insensibility and would be appropriate for on-farm euthanasia of turkeys of various ages and size.On-farm euthanasia is a critical welfare issue in the poultry industry and can be particularly difficult to perform on mature turkeys due to their size. We evaluated the efficacy of two commercially available non-penetrating captive bolt devices, the Zephyr-EXL and the Turkey Euthanasia Device (TED), on 253 turkeys at three stages of production: 4–5, 10, and 15–20 weeks of age. Effectiveness of each device was measured using both ante- and post-mortem measures. Application of the Zephyr-EXL resulted in a greater success rate (immediate abolishment of brainstem reflexes) compared to the TED (97.6% vs. 89.3%, p = 0.0145). Times to last movement (p = 0.102) and cardiac arrest (p = 0.164) did not differ between devices. Ante- and post-mortem measures of trauma and hemorrhage were highly correlated. Skull fractures and gross subdural hemorrhage (SDH) were present in 100% of birds euthanized with both the Zephyr-EXL and TED devices. Gross SDH scores were greater in birds killed with the Zephyr-EXL than the TED (p < 0.001). Microscopic SDH scores indicated moderate to severe hemorrhage in 92% of turkeys for the Zephyr-EXL and 96% of turkeys for the TED, with no difference between devices (p = 0.844). Overall, both devices were highly effective inducing immediate insensibility through traumatic brain injury and are reliable, single-step methods for on-farm euthanasia of turkeys.

Effectiveness of pneumatically powered penetrating and non-penetrating captive bolts in stunning cattle

This study assessed the effectiveness of penetrating (PCB; 190 psi; N = 363) and non-penetrating captive bolt guns (NPCB; 210–220 psi; N = 92) to stun a total of 455 cattle (Zebu and Zebu Cross). Physical bolt parameters (momentum, kinetic energy and energy density) were evaluated. Clinical indicators of brain function were recorded after stunning (GR), after being hoisted (HO) and at the bleeding rail (BL). Physical bolt parameters (bolt velocity, momentum, kinetic energy, energy density and sectional density) were significantly higher (P < 0.001) for PCB. The need for two or more shots was more frequent for NPCB (210–220 psi; 29% vs. 12%, P < 0.001). Cattle were more likely to collapse at first shot with PCB (190 psi; 99%) compared to NPCB (91%; P < 0.002) which can be attributed to the higher values of bolt physical parameters. Incidence of eyeball rotation (5% vs. 1%) and righting behaviour (7% vs. 1%) were higher (P < 0.001) for NPCB (210–220 psi) at GR than PCB. The NPCB with 210–220 psi had a higher frequency of response to nostril stimulation (2% vs. 0%; P < 0.001) than PCB. Rhythmic respiration was more frequently found for NPCB with 210–220 psi at GR, HO and BL. Therefore, PCB with 190 psi was more effective in ensuring unconsciousness in cattle.

Efficacy of Blunt Force Trauma, a Novel Mechanical Cervical Dislocation Device, and a Non-Penetrating Captive Bolt Device for On-Farm Euthanasia of Pre-Weaned Kits, Growers, and Adult Commercial Meat Rabbits.

Simple SummaryDeveloping effective and humane on-farm euthanasia methods is essential for all livestock industries to ensure that animals do not suffer and are killed humanely. Approved methods are lacking for commercial meat rabbits, potentially leading to poor welfare. We assessed several methods of on-farm killing of cull rabbits of different ages to determine which methods were most effective and humane. These included blunt force trauma (the most commonly used method on rabbit farms), a novel mechanical cervical dislocation device, and a non-penetrating captive bolt device. We evaluated method effectiveness by examining animal reflexes and behaviours after applying the method as well as by examining radiographs of rabbit heads for signs of skull damage, and by assessing the degree of trauma to the brain through dissection and microscopy, because more trauma is generally correlated with enhanced method effectiveness and irreversibility. We found that blunt force trauma resulted in an unacceptably high failure rate, particularly in mature rabbits, whereas the mechanical cervical dislocation and non-penetrating captive bolt devices were both highly effective for killing rabbits humanely and irreversibly. The non-penetrating captive bolt device was the most effective with a 100% success rate and could be used on all rabbits weighing more than 150 g.The commercial meat rabbit industry is without validated on-farm euthanasia methods, potentially resulting in inadequate euthanasia protocols. We evaluated blunt force trauma (BFT), a mechanical cervical dislocation device (MCD), and a non-penetrating captive bolt device (NPCB) for euthanasia of pre-weaned kits, growers, and adult rabbits. Trials were conducted on three commercial meat rabbit farms using 170 cull rabbits. Insensibility was assessed by evaluating absence of brainstem and spinal reflexes, rhythmic breathing, and vocalizations. Survey radiographs on a subsample of rabbits (n = 12) confirmed tissue damage prior to gross dissection and microscopic evaluation. All 63 rabbits euthanized by the NPCB device were rendered immediately and irreversibly insensible. The MCD device was effective in 46 of 49 (94%) rabbits. Method failure was highest for BFT with euthanasia failures in 13 of 58 (22%) rabbits. Microscopically, brain sections from rabbits killed with the NPCB device had significantly more damage than those from rabbits killed with BFT (p = 0.001). We conclude that BFT is neither consistently humane nor effective as a euthanasia method. MCD is an accurate and reliable euthanasia method generally causing clean dislocation and immediate and irreversible insensibility, and the NPCB device was 100% effective and reliable in rabbits >150 g.

Technical contribution: evaluation of the efficacy of a non-penetrating captive bolt to euthanase dairy goat kids up to 30 days of age

AbstractThe objective of this study was to evaluate the effectiveness of a non-penetrating captive bolt (NPCB) to euthanase previously disbudded Saanen dairy goat kids (Capra hircus) up to 30 days of age and 9 kg bodyweight. Goats were euthanased by placing the muzzle of the NPCB behind the poll between the ears with the goat's head bent so its chin was touching its chest. The NPCB was either fired once (Experiment 1; n = 30) or twice in quick succession (Experiment 2; n = 103). Immediately after application of the NPCB and every 30 s thereafter, signs of sensibility (presence of brainstem reflexes) were assessed together with the presence of cardiac activity, convulsions and rhythmic respiration, until cardiac activity ceased. In Experiment 1, 27 of the 30 goat kids were rendered immediately insensible and remained insensible until cardiac activity ceased; brainstem reflexes (the blink reflex) and rhythmic respiration remained present in three of the animals after application of the NPCB. In Experiment 2, all goat kids were rendered immediately insensible without return to sensibility prior to cessation of cardiac activity and death. In conclusion, applying the NPCB twice in close succession, behind the poll between the ears with the goat's head bent so its chin was touching its chest, reliably caused immediate and sustained insensibility followed by death in Saanen goat kids up to 30 days of age and 9 kg bodyweight.

Humane euthanasia of neonates I: validation of the effectiveness of the Zephyr EXL non-penetrating captive-bolt euthanasia system on neonate piglets up to 10.9 kg live-weight

AbstractTo determine if mechanical blunt force trauma using a non-penetrating captive bolt was a viable method of producing an immediate stun/kill in neonate piglets (Sus scrofa domesticus) as an alternative to manual blunt force trauma. Piglets (n = 60) were acquired from a local producer and allocated to one of five weight ranges: birth weight to 3 kg (n = 12); 3 to 5 kg (n = 11); 5 to 7 kg (n = 13); 7 to 9 kg (n = 13); and 9 to 11 kg (n = 11). These piglets with an average live-weight of 6.1 kg were anaesthetised and electroencephalogram (EEG) recording electrodes inserted sub-dermally over the right cranium to allow recording of Visual Evoked Potentials (VEPs). Following recording of baseline VEPs in the anaesthetised state, the piglet was shot once in the frontal-parietal position with a Bock Industries Zephyr EXL non-penetrating captive bolt powered by 120 psi air pressure. Movement scoring, behavioural indices of loss of brain function and VEPs were monitored throughout. VEPs were lost immediately in all piglets shot when the head was resting on a hard surface. This experiment demonstrates that mechanical blunt-force trauma, using a single-shot, non-penetrating captive bolt, such as the Zephyr EXL, provides for an immediate stun kill in neonate piglets up to 10.9 kg live-weight. This immediacy of action, combined with reproducible effects will improve the welfare of piglets to be subjected to on-farm euthanasia due to disease, ill-thrift or other commercial concerns.

Evaluation of the efficacy of a non-penetrating captive bolt to euthanase neonatal goats up to 48 hours of age

AbstractManual blunt force trauma is a common method of euthanasia or culling of goat kids, however it is difficult to apply consistently and may vary in effectiveness. Therefore, a controlled mechanical method is needed. The overall objective of this research was to evaluate the effectiveness of a non-penetrating captive bolt (NPCB) to euthanase goats (Capra hircus) up to 48 h of age. In a pilot study (n = 27), the optimum anatomical site for placement of the NPCB was evaluated using signs of insensibility and death, and post mortem assessment of traumatic brain injury. Three different anatomical sites (frontal bone, poll or behind the poll) were evaluated. In Experiment 1 (n = 100), goats were euthanased using the optimum anatomical placement determined in the pilot study and the presence of brainstem reflexes, rhythmic respiration, convulsions and cardiac activity were recorded. In Experiment 2 (n = 7), electroencephalogram (EEG) was recorded to assess awareness following application of the NPCB. Results from the pilot study showed that immediate insensibility followed by death was achieved when the muzzle of the NPCB was positioned behind the poll and the goat's head was bent so that the chin touched the chest. In Experiment 1, all goats were rendered immediately insensible without return to sensibility prior to cessation of cardiac activity. In Experiment 2, application of the NPCB resulted in the immediate onset of EEG activity which was incompatible with awareness. In conclusion, the NPCB reliably caused immediate insensibility and death in goats up to 48 h of age.

A note comparing the welfare of Zebu cattle following three stunning-slaughter methods

The objective of this study was to assess welfare of cattle during bleeding after slaughter with or without stunning. A total of 434 bulls were distributed across three slaughter treatments: penetrating captive bolt stunning followed by chest sticking (PCB, N=279), non-penetrating captive bolt stunning followed by halal slaughter (NPCB, N=67) and shechita without previous stunning (SHE, N=88). Four measures of possible consciousness and return to sensibility were recorded 20 and 60 s after bleeding as welfare indicators. They were the frequencies of responses to nostril stimulation and tongue pinch, spontaneous eye blinking, and rhythmic breathing. All responses were absent in stunned cattle at both 20 and 60 s, and in SHE cattle 7, 4, 10, and 100% of the animals presented these responses, respectively. Repeat shots were required for 46% NPCB and 2% PCB (P<0.05). The application of religious slaughter without previous stunning may result in greater risk of cattle suffering, pain and distress at slaughter.

Assessment of nonpenetrating captive bolt stunning followed by electrical induction of cardiac arrest in veal calves.

The purpose of this study was to evaluate the impact of nonpenetrating captive bolt stunning followed by electrical induction of cardiac arrest on veal calf welfare, veal quality, and blood yield. Ninety calves from the same farm were randomly assigned to 1 of 2 treatment groups in a balanced unpaired comparison design. The first treatment group (the "head-only" method-application of the pneumatic nonpenetrating stun to the frontal plate of the skull at the intersection of 2 imaginary lines extending from the lateral canthus to the opposite poll [CONTROL]) was stunned with a nonpenetrating captive bolt gun ( = 45). The second group ( = 45) was stunned with a nonpenetrating captive bolt gun followed by secondary electrical induction of cardiac arrest (the "head/heart" method-initial application of the pneumatic nonpenetrating captive bolt stun followed by 1 s application of an electrical stun to the ventral region of the ribcage directly caudal to the junction of the humerus and scapula while the stunned calf was in lateral recumbence [HEAD/HEART]). Stunning efficacy was the indicator of animal welfare used in this study. All calves were instantly rendered insensible by the initial stun and did not display common indicators of return to consciousness. For meat quality evaluation, all samples were collected from the 12th rib region of the longissimus thoracis. Meat samples were evaluated for color, drip loss, ultimate pH, cook loss, and Warner-Bratzler shear force. The L* values (measure of meat color lightness) were darker ( < 0.05) in the HEAD/HEART group (45.08 ± 0.72) than the CONTROL group (47.10 ± 0.72). There were no differences ( > 0.05) observed in a* (redness) and b* (yellowness) values between treatments. No differences ( > 0.05) were observed in drip loss, ultimate pH, cook loss, and Warner-Bratzler shear force. The blood yield from the CONTROL group (7,217.9 ± 143.5 g) was greater ( < 0.05) than that from the HEAD/HEART group (6,656.4 ± 143.5 g). Overall, the data indicated no difference between the CONTROL and HEAD/HEART groups with regard to animal welfare because the initial stun was effective in all calves. However, longissimus thoracis L* and blood yield were negatively impacted by the HEAD/HEART method. The data in this study suggest that secondary induction of cardiac arrest is not necessary with effective nonpenetrating captive bolt stunning in veal calves.

Effectiveness of a nonpenetrating captive bolt for euthanasia of piglets less than 3 d of age1

The objective of this study was to determine the effectiveness of a nonpenetrating captive bolt (NPCB), the Zephyr-Euthanasia (Zephyr-E), for euthanasia of neonatal piglets<72 h of age using signs of insensibility and death, as well as postmortem assessment of traumatic brain injury (TBI). The Zephyr-E was used by 10 stock people to euthanize 100 low viability neonatal piglets from 3 commercial farrowing units and 1 research farm. Brainstem reflexes, convulsions, and heartbeat were used to assess insensibility, time of brain death, and cardiac arrest after Zephyr-E application. Hemorrhage severity and skull fracture displacement (FD) were quantified from computed tomography scans (n=10), macroscopic scoring was used to assess brain hemorrhage and skull fracture (SK) severity (n=100), and microscopic scoring was used to assess subdural (SDH) and parenchymal (PH) hemorrhage within specific brain regions that are responsible for consciousness and vital function (n=10). All 100 piglets were rendered immediately insensible without return to sensibility. On average, clonic convulsions (CC) ceased in 101 s (±7.4 SE), brain death was achieved in 229 s (±9.18 SE), and cardiac arrest occurred in 420 s (±13.57 SE). Time of cardiac arrest differed significantly among stock people when either body weight (BW: P=0.0053) or body mass index (BMI: P=0.0059) was used as a covariate. The BMI was inversely related to the duration of CC (P=0.0227). Moderate to severe hemorrhage severity was reported in 9 of 10 piglets. There was no relationship between FD and BW (P=0.8408) or BMI (P=0.6439). Macroscopic analyses indicated moderate to severe hemorrhage and SK in all piglets. No differences were found among brain sections for SDH (P=0.2302); PH was greater in the cerebral cortex than in the midbrain and brainstem (P=0.0328). The Zephyr-E NPCB reliably caused immediate, sustained insensibility followed by death in neonatal piglets. Postmortem assessment confirmed that application of the Zephyr-E caused widespread, irreversible brain damage.