Mental Health Impact of Mass Depopulation of Swine on Veterinarians During COVID-19 Infrastructure Breakdown

Perceptions of swine industry stakeholders on the use of water-based foam, high-expansion nitrogen foam, and carbon dioxide gas as methods of swine depopulation

Emergency contingency plans for the U.S. swine industry, including depopulation protocols, that are essential to limit the spread of sudden outbreaks of infectious diseases is currently lacking. Although novel depopulation methods such as water-based foam (WBF) and high-expansion nitrogen foam (N2F) are being investigated, carbon dioxide gas (CO2) is currently the only American Veterinary Medical Association (AVMA)-preferred method capable of depopulation of groups of swine. The AVMA's assessment of depopulation methods evaluates efficacy, animal welfare implications, and caretaker physical and mental health, in addition to logistical aspects of equipment acquisition and use. These criteria are best gauged using input from individuals familiar with the operations within the swine industry. Therefore, the aim of this study was to describe swine industry stakeholders' perceptions of WBF, N2F and CO2 depopulation after a large-scale field demonstration. A survey was created based on the criteria outlined in the AVMA Depopulation Guidelines to determine respondent perceptions of each method. Swine industry stakeholders of various backgrounds (N=32) were recruited and invited to observe demonstrations of each method. Mixed linear regression models were built to investigate the association between survey question scores and depopulation method. Respondents varied in occupation, with 37.5 % (12/32) belonging to an academic institution or veterinary medical association, 21.9 % (7/32) to a pork organization, and 18.8 % (6/32) to state or federal regulatory agencies. The remaining 21.8 % (7/32) was a group consisting of one producer (3.1 %), one individual in swine industry retail (3.1 %), one veterinarian in a private practice setting (3.1 %) and four (12.5 %) who did not disclose their affiliation. Average experience (±SD) in the swine industry was 14.4 (±12.4) years, and 40.6 % (13/32) had previous experience of any type in swine depopulation. The overall method impression scores revealed that WBF and N2F were perceived as better options compared to CO2 (P < 0.001). WBF and N2F scored higher on pig distress mitigation, protecting emotional and psychological health of personnel, and equipment accessibility compared to CO2 (P < 0.001). Stakeholders without a clear affiliation provided higher scores compared those affiliated with regulatory agencies, pork associations or academic or veterinary institutions, regarding minimizing pig distress, method safety/accessibility, and overall method impression. Few demographic differences were observed, suggesting similar perceptions of the three depopulation methods during the demonstrations. This industry feedback is valuable for future considerations, method improvements and facilitation for possible implementations into future response plans.

Factors Associated with Behavioral Health Outcomes in Veterinarians Involved in Disaster Responses

OBJECTIVE

The objective of this study was to determine what factors are associated with behavioral health in veterinary disaster responders.

METHODS

An online cross-sectional survey was distributed via snowball sampling. Results were analyzed using chi-square analyses.

RESULTS

Responses from 237 veterinarians were analyzed. Being involved in more than 1 disaster event was associated with higher anxiety and/or depression (43.4% vs 28.6%, respectively), difficulty with relationships (28.1% vs 14.3%, respectively), and a greater prevalence of sleep problems (44.6% vs 28.0%, respectively) compared to only being involved in 1 event. Veterinarians that were deployed longer than 2 months had the highest prevalence of anxiety and/or depression (43.9%) and sleep problems (50.0%). Veterinarians that received behavioral health training before deployment had lower rates of anxiety and/or depression (27.8% vs 42.9%, respectively) compared to those who did not receive training. Respondents involved with depopulation had the highest rates of anxiety and/or depression (66.7%) and sleep problems (58.1%).

CONCLUSIONS

Factors associated with behavioral health outcomes included the number and length of deployments, receiving behavioral health training, and being involved in depopulation. To reduce the risk of behavioral health outcomes, interventions such as time-off and behavioral health support are needed.

Measuring mental ill-health in the veterinary industry: A systematic review

Many instruments have been developed to examine and quantify symptoms of psychopathology. The main objective of this systematic review was to examine the instrument choice employed to measure mental ill-health in professionals working in the veterinary industry and reporting of psychometric testing of these instruments by researchers. 78 papers were reviewed. A total of 73 different instruments used to measure 19 symptoms of mental ill-health were identified. Quality assessment of included papers indicated 9 were low, 63 were moderate, and 6 were high quality. Reliability testing was conducted and reported in 36 papers and validity testing was reported in 23 papers. There is considerable heterogeneity in instrument choice measuring symptoms of mental ill-health in this population and inconsistency in conducting and reporting psychometric testing of instruments across studies. Adopting commonly employed instruments that yield high quality data in psychometric testing of instruments would be beneficial at advancing understanding in this field.

Swine industry stakeholders' perception on the use of water-based foam as an emergency mass depopulation method

The U.S. pork supply chain is vulnerable to various internal and external threats and in need of prompt, comprehensive response plans. Under urgent circumstances, for example in the case of foreign disease incursions, swine farms will have to perform on-farm animal depopulation to prevent disease spread. Several animal depopulation methods including water-based foam (WBF) have been proposed and are under evaluation for feasibility in the field. However, the psychological/emotional impacts of applying depopulation methods for personnel managing and carrying on the tasks are not currently well understood. Thus, this study aimed to investigate WBF as an alternative for depopulation compared to existing methods approved by the American Veterinary Medical Association. Swine industry stakeholders were invited to voluntarily observe a WBF depopulation trial and to provide their self-reported perspectives before and after the observation. A survey was designed to explore key areas on expected and perceived method effectiveness, efficiency, and animal welfare considerations, as well as to evaluate short-term post-observation psychological impacts. Among 42 recruited stakeholders, 31.0% (13/42) were educators/researchers followed by animal health officials (26.2%, 11/42) and veterinarians (23.8%, 10/42), with an average of 11.7 ± 12.6 (n = 39) years of work experience. After the trial, respondents' positive perception of WBF depopulation increased specifically regarding the animal loading process being less stressful than restrained in-barn depopulation options (P = 0.003) and by the observation of fewer swine escape attempts and vocalizations than expected (P < 0.001). Respondents' positive perception of WBF also increased regarding to the time required to fill the trailer with foam, to stop hearing animal vocalization, and stop hearing animal movement, as the observed trial times were faster than their pre-observation estimates (P < 0.001). Additionally, 79.5% (31/39) of respondents agreed that the rapid destruction of animal populations had priority over animal welfare under urgent scenarios. Minor post-traumatic stress disorder-like (PTSD-like) symptoms from the observed trials were reported (26.7%, 4/15 respondents) one month after the observation. This study showed that the WBF depopulation process was perceived positively by swine stakeholders and may have limited short-term psychological impacts on personnel involved in animal depopulation.

Psychological implications of humane endings on the veterinary profession

The veterinary profession has a unique responsibility to animals during the final stages of their lives. The veterinarian's obligations extend to humane endings, involving all species of animals in a range of circumstances including, but not limited to, euthanasia of individually owned animals, euthanasia of animals for research purposes, depopulation of animals during emergencies, and slaughter of animals raised for food. The veterinary profession continues to improve animal welfare through advances in end-of-life decision-making and humane killing techniques,1-3 but the psychological impacts on veterinarians have not received the same level of consideration. Building on the influential AVMA Humane Endings Guideline, the AVMA recognizes that support for the mental health of veterinarians engaged in such activities needs to be a priority. This article aims to provide the foundation and rationale for improved preparation and establishment of sustainable mental health resources and to offer recommendations on pragmatic solutions to support and prepare veterinary professionals as leaders impacted by participation in humane endings-related activities. While end-of-life decision-making and implementation may present mental health challenges to veterinarians, it is crucial to recognize that there are stressors specific to each situation and that every individual's experience is valid. Addressing the mental health issues surrounding the decision-making process and implementation of humane endings activities start with a comprehensive understanding of each activity's unique context and the veterinarian's leadership role. Therefore, this article highlights the psychological impact of depopulation and its similarities and exclusive challenges compared with euthanasia and humane slaughter.

Water-based medium-expansion foam depopulation of adult cattle

Current options for depopulation of adult cattle are limited, have logistic constraints, and may not be practical on a large scale. Aspirated water-based foam (WBF) has been shown to be successful in depopulating poultry and swine but has yet to be tested in cattle. WBF is advantageous because necessary equipment can be readily available, easy to use, and presents minimal personnel risk. With the use of a modified rendering trailer in a field setting, we evaluated the efficacy of aspirated WBF for depopulation of adult cattle. Water-based medium-expansion foam was added to the trailer holding cattle to a depth of approximately 50 cm greater than head height. The study was conducted as a gated design and the initial trial was conducted using six anesthetized and six conscious animals for verification of the process and followed by four replicates each containing 18 conscious cattle. A total of 84 cattle were used, with a subset (n = 52) implanted with subcutaneous bio-loggers that recorded activity and electrocardiograms. Cattle were loaded onto the trailer and three gasoline-powered water pumps delivered foam into the trailer followed by a 15-min foam dwell period. Average (± SD) time to completely fill the trailer with foam was 84.8 ± 11.0 s. No animal vocalizations were heard during foam application or the dwell period, and all cattle were confirmed dead upon removal from the trailer after 15 min of immersion. Necropsies of a subset of cattle revealed foam extending to at least the tracheal bifurcation in all cattle and distal to this level in 67% (8/12) animals. Time to cessation of movement, which served as a proxy for loss of consciousness, was 2.5 ± 1.3 min and time to cardiac death was 8.5 ± 2.5 min as determined by data from animals carrying subcutaneous bio-loggers. The results of this study indicate that WBF is a rapid and effective method for depopulation of adult cattle with potential advantages in speed and carcass handling and disposal over current methods.

The Rise of Heatstroke as a Method of Depopulating Pigs and Poultry: Implications for the US Veterinary Profession

Depopulation of food-producing animals is becoming increasingly common in response to both disease outbreaks and supply chain disruptions. In 2019, the American Veterinary Medical Association released depopulation guidelines classifying certain heatstroke-based killing methods as "permitted in constrained circumstances", when circumstances of the emergency constrain reasonable implementation of "preferred" methods. Since then, tens of millions of birds and pigs have been killed by such methods, termed ventilation shutdown (VSD) Plus Heat and VSD Plus High Temperature and Humidity. While no research using validated measures of animal welfare assessment has been performed on these methods, their pathophysiology suggests that animals are likely to experience pain, anxiety, nausea, and heat distress prior to loss of consciousness. Heatstroke-based methods may result in prolonged suffering and often do not achieve 100% mortality. Potential and available alternative depopulation methods are briefly reviewed. The veterinary profession's ethical obligation to protect animal welfare in the context of depopulations is discussed.

Reviewing a Decade of Change for Veterinarians: Past, Present and Gaps in Researching Stress, Coping and Mental Health Risks

Veterinary medicine is a highly complex profession that includes a very specific set of stressors that range from individual to social aspects, with several of them being relevant risk factors for a variety of conditions. The aim of this systematic review was to identify and cluster the material on stressors and suicidality in the veterinarian practice published during the last 10 years. The systematic review was conducted employing the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed, PsycNet, Google Scholar, Medline, PsycINFO, PSYNDEX and Web of Science (2012-present) by two independent researchers resulting in the inclusion of 30 quantitative and mixed methods studies. Results of these studies on stressors were categorized using the bio-psycho-social model showing that social stressors play a prominent role. This category includes the largest number of stressors indicating that the human-human interactions in the veterinarian practice are the main stressor, underlining that training in communication techniques is a potential starting point for interventions. In addition to stressors, the results showed an additional category "psychological consequences" describing mental health disorders and suicide. Although there are still gaps in research there is enough evidence to establish more tailored health promotion measures for veterinarians.

Mass Depopulation of Swine during COVID-19: An Exploration of Swine Veterinarians' Perspectives

Simple Summary

This study was designed to better understand the mental health of U.S. swine veterinarians who were involved in the mass depopulation events related to COVID-19. A total of 25 swine veterinarians, participants from a larger quantitative study, volunteered to be interviewed about their experiences related to the COVID-19 mass depopulation event. The themes that arose from these interviews included: (1) the need to be better prepared for crisis events; (2) lack of public understanding; (3) moral distress; (4) empathy for others, especially young veterinarians; (5) sources of support; (6) pride, honor and gratitude; and (7) an overarching theme of emotional distancing and detachment—concerns external to one’s own mental health. Based on these results, we recommend additional training and supportive services for those who might be involved in future depopulation efforts.

Abstract

This qualitative study (n = 25) was created to better understand the mental health of U.S. swine veterinarians who were involved in the mass depopulation events related to COVID-19. A total of 25 swine veterinarians, participants in a previous larger quantitative study, volunteered to be interviewed about their experiences related to the COVID-19 mass depopulation event. Themes that emerged from these interviews included: (1) the need to be better prepared for crisis events; (2) lack of public understanding; (3) moral distress; (4) empathy for others, especially young veterinarians; (5) sources of support; (6) pride, honor and gratitude; and (7) an overarching theme of emotional distancing and detachment—concerns external to one’s own mental health. Based on our results, we recommend additional training and supportive services for those who might be involved in future depopulation efforts. Additionally, we suggest that the veterinary profession prioritize public education campaigns to help the public better understand the need for depopulation.

Reliability of water-based medium-expansion foam as a depopulation method for nursery pigs and cull sows

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 m³ (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-m³ 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.

Quick Responses of Canadian Social Scientists to COVID-19: A Case Study of the 2020 Federal COVID-19-Specific Grant Recipients

COVID-19 prompted an abundance of independent and collaborative quick response disaster research (QRDR) initiatives globally. The 2020 federal COVID-19-driven granting opportunities initiated the first official QRDR effort in Canadian history, engaging social scientists to rapidly address the pandemic-related societal influences. This study aims to portray the landscape of this nascent social science QRDR workforce through the first round of federal COVID-19-specific grant recipients. A case study approach was employed to analyze 337 social science projects with 1119 associated researchers, examining the demographic structure of these COVID-19-driven social science researchers and their research projects’ characteristics. Accordingly, the findings are presented through the following two streams: (1) From a researcher perspective, this case study describes researcher typology, geographic location, primary discipline, and educational background, highlighting the diverse characteristics of social sciences researchers, and uneven research development across Canada. (2) From a research project perspective, this case study identifies and synthesizes research project subjects, themes, collaborations, and Canadian distinctions, emphasizing the need for galvanizing cooperation and focusing on uniquely Canadian contexts. The case study illustrates challenges associated with data curation that pose barriers to developing a nuanced understanding of the Canadian social science community COVID-19 research landscape. Consequently, the case study develops three recommendations to improve QRDR development in Canada: promoting information transparency, dissemination, and updates; improving hazards and disaster research workforce evaluation; and enhancing multi-stakeholder cooperation.