The inflammatory response evokes changes in behaviour including increased thermoregulatory activities and sleep, reduced social exploration and appetite, and altered food preferences. This sickness response also includes feelings of lethargy, depression, and pain, collectively referred to as ‘malaise’. Recent experiments involving laboratory rodents reveal information about proximate mechanisms of sickness behaviour, but scant information exists about how sickness behaviour is expressed by farmed species or within social environments. The behavioural needs of ill individuals differ from those of conspecifics, and failure to accommodate the needs of ill individuals may exacerbate suffering. Policy makers, industry and animal welfare certification programs recommend hospital pens to address the housing and handling needs of ill livestock and to reduce risks of disease transmission. However, a survey of swine farms in Ontario, Canada revealed deficiencies in the use of hospital pens and gaps in knowledge about best management practices for this vulnerable population. There is considerable scope to improve the welfare and husbandry of ill and at risk animals through effective use of hospital pens and supportive therapies.

The objective of this study was to evaluate the effects of chamber stocking rate on facets of animal welfare and efficacy during gas euthanasia of young pigs (Sus scrofa domesticus). Crossbred pigs (390 neonatal and 270 weaned) designated for euthanasia at production farms were randomly assigned to group sizes of one, two, four, or six pigs. Gas euthanasia of each piglet group was performed in a Euthanex® AgPro chamber. The chamber air was gradually displaced with CO2 gas over 5 min to establish an in-chamber concentration of approximately 80% CO2. Pigs remained in that atmosphere for an additional dwell period of at least 5 min. Higher stocking rates were associated with higher CO2 concentrations after gradual fill for both age groups. While there was no evidence of an effect of stocking rate on latencies to loss of posture or last movement in neonatal pigs, there was evidence of an effect on all measured efficacy variables in weaned pigs, with grouped pigs faster to succumb than solitary pigs. This finding is consistent with expected consequences of higher CO2 concentration at increased stocking densities. Aversive states and behaviours of focal pigs in the chamber were scored from video. Weaned solitary pigs displayed a high incidence of pacing and may have experienced isolation distress. Escape attempts were absent in neonates and not linearly affected by stocking rate in weaned pigs. Although the risk of hazardous interactions was correlated with group size, this study provided no evidence that isolation during gas euthanasia would benefit animal welfare.

The 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.

Veterinarians are increasingly looked to for guidance on matters relating to animal welfare, yet little is known about US veterinary students’ attitudes and beliefs about animals. In 2019, we surveyed all first-year veterinary students at a major US veterinary college (n = 123) before and after taking a required one-credit introductory animal welfare course. Attitudes were measured using the Pests, Pets and Profit (PPP) scale and belief in animal mind (BAM) was measured using an ad hoc measure adapted from previous work. Pre- and post-course comparisons indicated the introductory animal welfare course had no immediate effect on veterinary students’ attitudes or BAM. Veterinary students’ attitudes were most positive for animals considered pets, followed by pests and those used for profit. Students believed most species possess a wide variety of mental capacities, including many secondary emotions often considered uniquely human (eg guilt, embarrassment, jealousy). Sociodemographic variables consistently associated with more positive attitudes towards animals were: female gender, vegetarianism and liberal political ideology. Preferring a career involving large or food animal practice was consistently associated with less positive attitudes towards animals. Belief in animal mind explained 3% of the variation in attitude scores, whereas sociodemographic variables explained 49% of variation in attitude scores. Female gender, vegetarianism and preferring small (vs large or food animal practice) were all associated with greater BAM scores. Understanding veterinary student attitudes towards animals and beliefs about the mental capacities of animals is important when evaluating a veterinarian's ability to adhere to their oath.

Severely depressed pigs exhibit differences in a number of important parameters that may affect gas euthanasia, including decreased respiration rate and tidal volume. Hence, the objectives of this study were to assess the efficacy and animal welfare implications of gas euthanasia of suckling pigs with varied disease severity (severely depressed [DP] vs other [OT]). A 2 × 2 factorial design was utilised with two gas types (carbon dioxide [CO2]; argon [Ar]) and two flow rates (G = gradual, 35% box volume exchange per min [BVE min−1]; P = prefill + 20% BVE min−1). Sixty-two pigs were enrolled and tested as DP/OT pairs in each gas treatment combination. Pigs identified for euthanasia were assigned a subjective depression score (0 = normal to 3 = severely depressed). Pigs scored 3 and ≤ 1 were categorised as DP and OT, respectively. Significantly lower respiration, rectal temperature, pulse and weight were observed for the DP pigs relative to OT. Pigs were assessed for behavioural indicators of efficacy and welfare. No differences were observed between DP and OT when using P-CO2 or G-CO2. However in P-Ar, DP had greater latency to loss of consciousness relative to OT (212 [± 22] vs 77 [± 22] s), decreased latency to last limb movement (511 [± 72] vs 816 [± 72] s), greater duration of open-mouth breathing (151 [± 21] vs 69 [± 21] s), decreased duration ataxia (101 [± 42] vs 188 [± 42] s) and decreased righting response (27 [± 11] vs 63 [± 11] s). The G-Ar treatment was removed due to ethical concerns associated with prolonged induction. In conclusion, depression score did not affect pig responses to euthanasia with CO2 gas, but did affect responses to Ar. Furthermore, Ar was associated with a prolonged euthanasia process, including frequencies and durations of distress behaviours.

Manual 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.

The objective of this study was to evaluate the effects of chamber stocking rate on facets of animal welfare and efficacy during euthanasia of weaned pigs (Sus scrofa domesticus) with argon gas. Two hundred and thirty-three weaned pigs designated for euthanasia at a commercial production farm were randomly assigned to group sizes of one, two, or six pigs. Gas euthanasia of each piglet group was performed in a Euthanex® AgPro chamber. The chamber was filled with argon gas for 6 min in order to reduce the oxygen concentration to less than 2%. Pigs were then placed into the pre-filled chamber and gas flow was continued at a high rate to displace introduced air and re-establish a fatally low residual oxygen concentration. Pigs remained in the chamber for 10 min and were then removed to test for signs of sensibility and life. There was no significant evidence of an effect of stocking rate on focal pig latencies to onset of neuromuscular excitation or last movement, as scored from video recordings. Solitary pigs were more likely to pace and make righting attempts in the chamber than paired or grouped focal pigs, although pigs in higher stocking rate treatments tended to retain posture longer. The results of this study do not support seclusion during argon gas euthanasia as a method of improving animal welfare. The portable chamber did not facilitate a truly pre-filled atmosphere for euthanasia, although the procedure used in this study was consistently effective.

Lameness in breeding swine has a large negative economic impact and is a welfare concern. Pain-related behaviour, such as postural changes, may be used to evaluate the presence and severity of pain in animals. The objective of this work was to determine the effects of flunixin meglumine (FM) and meloxicam (M) on postural changes in lame sows. Lameness was induced in 24 mature sows (Sus scrofa) using a chemical synovitis model. Three treatments were compared: FM (2.2 mg kg−1; n = 24, intramuscular [IM]), M (1.0 mg kg−1; n = 24, by mouth [PO]) and sterile saline (equivalent volume to FM; n = 24 [IM]), administered approximately 28 and 52 h after lameness induction. Behavioural data were collected in the home pen during 12-h periods and quantified using 15-min scan sampling on the day prior to (-24 h; Day-1) through +168 h post lameness induction. Frequency of behaviour was analysed by day using generalised linear mixed model methods. The frequency of standing postures significantly decreased and lying postures increased 24-72 h post lameness induction relative to baseline day. All postures returned to baseline frequencies by +168 h. Meloxicam-treated sows demonstrated lower frequencies of lying postures +48 and +72 h after lameness induction compared to saline-treated sows. Flunixin-treated sows did not differ in lying behaviours compared to saline-treated sows. No differences were noted in standing or sitting postures between treatments. The results of this study suggest that meloxicam mitigates pain sensitivity as demonstrated by higher frequency of standing and lower frequency of lying compared to saline-treated sows.

Timely euthanasia on swine farms can help to reduce the incidence of poor welfare outcomes for compromised pigs (Sus scrofa) when recovery is prolonged or impossible. Timely euthanasia relies upon caretakers’ abilities to identify compromised pigs and administer euthanasia in various environments. To determine appropriate timelines and most common reasons for on-farm euthanasia, an online survey was conducted with members of the United States National Pork Board. Additionally, two focus groups were conducted to investigate barriers and possible solutions associated with timely euthanasia. Clinical signs related to poor locomotion (57.6%), prolapses (47.2%), and hernias (43.5%) were identified by the greatest percentage of respondents who believed immediate euthanasia was warranted, while a greater percentage of respondents believed euthanasia was not warranted for clinical signs related to the integumentary (90.3%), reproductive (75.8%), and respiratory (67.5%) systems. The most common reason for euthanasia was poor body condition in pre-weaned piglets and non-ambulatory or severely weak for both breeding and non-breeding pigs. In the focus groups, two themes were identified when evaluating barriers to euthanasia on-farm, and participants agreed that making timely decisions relies upon several dimensions of risk analysis. An unsupportive farm culture was identified as a critical barrier to timely euthanasia decision-making, suggesting that caretaker characteristics may play a role in the success of any timely euthanasia programme. This present study has highlighted areas for future research and demonstrated the need to extend educational efforts both to swine industry leaders and producers to improve overall animal welfare by ensuring timely euthanasia in swine.

Lameness in breeding swine can cause severe pain leading to on-farm welfare issues and significant economic impacts. Non-steroidal anti-inflammatory drugs including meloxicam and flunixin meglumine are commonly used in veterinary medicine for their analgesic and anti-inflammatory properties. Pressure algometry and thermal sensitivity tests are non-invasive methods to quantify pain sensitivity using nociceptive thresholds to provoke withdrawal responses on lame and sound legs. The objective of this work was to determine the effects of these drugs on nociceptive thresholds in sows induced lame using pressure algometry and thermal sensitivity tests. Lameness was induced in 24 mature, mixed-parity sows using a chemical synovitis model and three treatments were compared: meloxicam (1.0 mg kg−1 PO), flunixin meglumine (2.2 mg kg−1 IM) and sterile saline (IM). Pressure algometry was measured on sound and lame rear legs with three replicates at three landmarks. Thermal sensitivity tests were done on sound and lame rear legs with three replicates using a thermal stimulus at one landmark. From 37 to 72 h after lameness induction, meloxicam- and flunixin meglumine-treated sows tolerated higher pressure algometer nociceptive thresholds compared to saline-treated sows. Changes in thermal nociceptive thresholds were evident at the Tmax time-points for meloxicam administration and 72 and 168 h post lameness induction for flunixin meglumine-treated sows. In conclusion, flunixin meglumine and meloxicam administration mitigated pain sensitivity in lame sows post lameness induction when pain sensitivity was evaluated with pressure algometry. These analgesic drugs may be a key tool to manage pain associated with lameness.