Jeff A. Lines

Blank cartridges provide the power source for the majority of captive bolt devices used for rendering animals unconscious prior to slaughter within the United Kingdom or euthanasia worldwide. This paper presents the results of the examination of cartridges as one of the variables that can contribute to an unsuccessful application of this method in practice. Variation was found in cartridge weight, propellant fill volume and velocity within boxes of 1000 cartridges. The variation found was greater in lower charge (1.00 grain) cartridges than in 3.00 grain cartridges, however velocity was found to be variable in both sets. For example, in vivo velocity measurements with 0.25″ calibre 3.00 grain cartridges demonstrated an average velocity of 50.8 m/s over 200 shots with a range of 35.7 to 62.9 m/s when used in the same device. This work demonstrates that variation in cartridge performance does occur and can be due to various factors such as fill volume and propellant function, and simply weighing cartridges cannot be used to determine function, therefore cartridge performance must be a factor that is considered in the event of a miss-stun.

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 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.

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.

A wide range of electronic dog training collars (e‐collars) is available in the UK, but information enabling purchasers to compare the important characteristics of these collars is not available. In this research, the electrical characteristics of 13 e‐collar models were examined, and an approach to ranking the strength of the electrical stimuli was developed. To achieve this, the electrical impedance of dogs' necks were measured so that e‐collars could be tested under realistic conditions. This impedance was found to be about 10 kΩ for wet dogs and 640 kΩ for dry dogs. Two replicates of eight e‐collar models and single copies of a further five models were then examined. The stimuli generated by these collars comprised sequences of short high‐voltage pulses. There were large differences between e‐collar models in the energy, peak voltage, number of pulses and duration of the pulses, but little variation between the replicates. The peak voltage varied with the impedance, from 6000V at an impedance of 500 kΩ to 100V at 5 kΩ. The highest voltages were generated for a few millionths of a second. Stimulus energy levels at the maximum strength setting with a 50 kΩ load ranged from 3.3 mJ to 287 mJ. A stimulus strength ranking indicator was then developed to enable the strengths of e‐collars with diverse electrical characteristics to be ranked. This ranking shows a wide range in the stimulus strengths of collars, and that the relationships between ‘momentary’ and ‘continuous’ stimuli for various models differ significantly.

Fish welfare at harvest is easily compromised by poor choice of handling and slaughter methods, lack of attention to detail and by unnecessary adherence to fish farming traditions. The harvest process comprises fasting the fish to empty the gut, crowding the fish, gathering and moving the fish using brails, fish pumps, and sometimes also road or boat transport and finally stunning and killing the fish. The harvesting processes commonly used for bass, bream, carp, catfish, cod, eel, halibut, pangasius, salmon, tilapia, trout, tuna and turbot are outlined. These harvesting processes are discussed; the consequences for fish welfare identified and practical tests which can be made at the harvest site highlighted. Welfare at harvest for the majority of farmed fish species can be improved by adopting and adapting existing procedures already known to be beneficial for fish welfare through their use in other fish farming systems or with other species. It is seldom necessary to develop completely new concepts or methods.

1. The objective was to assess carcass quality of broilers when they were stunned by immersing their heads in a waterbath with an electric current flowing from one side of it to the other, while a second small current passed through the body to the waterbath to prevent involuntary wing flapping. 2. The prevalence of wing, shoulder and breast fillet haemorrhages and of broken bones in the pectoral region was not greater than that resulting from the normal stunning practice in that plant (63 mA, 610 Hz pDC). 3. These results imply that carcass damage using this technique will be significantly lower than that which will result from the application of higher stunning currents required by the new EU slaughter poultry slaughter regulations.

1. The objective of this work was to investigate the feasibility of head only waterbath stunning as a means of generating immediate and long lasting unconsciousness while preventing wing flapping and avoiding carcass damage. 2. EEG measurements showed that immersion of the heads of the broilers for one second in a waterbath containing water of conductivity 2·5 mS/cm and a 50 Hz electric field of 10 V/cm resulted in immediate unconsciousness, and that increasing the electric field strength extended the duration of unconsciousness. 3. The passage of a 25–30 mA alternating current of frequency 2000 Hz through the broilers’ bodies suppressed the wing flapping that followed a stun. 4. When the body current and electric field were applied simultaneously, wing flapping was prevented and EEG signals were suppressed for over 30 seconds indicating that the immediate unconsciousness lasted long enough to facilitate humane slaughter.

A breast support conveyor has the potential to improve bird welfare by avoiding the need to invert and suspend broilers by their legs as they move from the point of shackling to entry into the electric waterbath. To evaluate its effect on welfare under commercial conditions, a breast support conveyor was installed under the conventional shackle line of a small poultry processing plant. A structured assessment of the behaviour of the birds indicated a significant decrease in struggling and wing flapping at the point of shackling, on the straight conveyor and at entry into the waterbath. This resulted in a lower prevalence of red wing tips and bruising in the first wing joint. The shackle line and conveyor in this installation, however, passed around a 90° corner, which appeared to cause more disturbance to the birds on the conveyor than to comparable birds suspended from shackles in the traditional manner. The results indicate that a breast support conveyor has the potential to improve bird welfare on straight shackle lines and that, because struggling activity and duration following shackling are reduced, the time between shackling and stunning could also be reduced using this method, further improving bird welfare. Breast support conveyors should not be used when the shackle lines have sharp bends.