Managing animal wellbeing: a preliminary survey of pig farmers

Landscape review about the decision to euthanize a compromised pig

Timely euthanasia of a compromised pig in farming practice has been identified as a critical topic in veterinary medicine. The questions 'why and when are pigs euthanized' and 'what influences the decision making process' need to be answered to improve the situation. In the past five years, work addressing these issues has been published in the literature, however, a synthesis of the findings is missing. With the help of a quantitative and qualitative analysis, this paper has generated a landscape review to outline major topics, the role of clinical signs and further influences on the decision to euthanize a pig. Due to the quantitative content analysis, 58 topics have been identified with the role of welfare as a justification and training for caretakers in making euthanasia decisions as the most frequently mentioned. The qualitative analysis of why and when a pig is euthanized generated a set of clinical signs for organ tracts, and a set of categories influencing the decision making process. The results outline the need to increase research on details specific to understanding how clinical signs evolve over time before euthanasia. In summary, the analysis provides an overview of work in the field and ideas on how to close knowledge gaps in the future. Moreover, the article contributes to harmonize efforts in the field and underlines the need for more research about the care of compromised and injured pigs.

Pigs' capacity to experience feelings and to suffer from tail lesion, ear lesion and lameness: Exploring citizens and pig farm and abattoir workers' knowledge and perceptions

The aim of this study was to gain insight into the perceptions of pig farm and abattoir workers as well as lay citizens regarding (1) sentience and (2) positive (intelligent and friendly) and negative (gluttonous, stubborn and dirty) attributes of pigs. We also aimed to investigate the (3) knowledge and perceptions of pig farm and abattoir workers on tail lesion, ear lesion and lameness in pigs and (4) the opinion of lay citizens regarding the likelihood of tail lesions, ear lesions, and lameness causing suffering in pigs and affecting meat quality. Chilean pig farm workers (n = 116), pig abattoir workers (n = 95), and lay citizens (n = 708) were invited on farm, at the abattoir and in public places, respectively, to participate in a survey. Answers were indicated using a 5-point Likert scale (0 = totally disagree; 4 = totally agree). Data were analysed using generalized linear models, including recruitment place and socio-demographic data as predictor variables. Female and lay citizens attributed pigs a higher capacity to experience feelings than male participants and pig farm and abattoir workers (p < 0.05). Lay citizens and workers recruited on farm described pigs as being more intelligent and friendly than those workers recruited at the abattoir (p < 0.001); recruitment place and sex were not associated with participants' perception regarding negative attributes of pigs (p > 0.05). Most lay citizens considered that tail lesions, ear lesions and lameness are likely to cause suffering in pigs and older participants had higher odds of agreeing that tail and ear lesions are likely to affect meat quality (p < 0.05). Finally, the risk factors for tail lesion, ear lesions and lameness pointed out by pig farm and abattoir workers is in line with what has been suggested by experts. Our findings contribute to understand the perception and values of all stakeholders regarding animal welfare, as it is crucial to improve the sustainability of animal production systems.

Effects of long-term use of the preferential COX-2 inhibitor meloxicam on growing pigs

Meloxicam, a preferential COX-2 inhibitor, is a commonly used NSAID in pigs. Besides having potential side effects on the gastrointestinal tract, this type of drug might potentially affect osteogenesis and chondrogenesis, processes relevant to growing pigs. Therefore, the effects of long-term meloxicam treatment on growing pigs were studied. Twelve piglets (n=6 receiving daily meloxicam 0.4 mg/kg orally from 48 until 110 days of age; n=6 receiving only applesauce (vehicle control)) were subjected to visual and objective gait analysis by pressure plate measurements at several time points. Following euthanasia a complete postmortem examination was performed and samples of the talus and distal tibia, including the distal physis, were collected. Trabecular bone microarchitecture was analysed by microCT scanning, bone stiffness by compression testing and growth plate morphology using light microscopy. Animals were not lame and gait patterns did not differ between the groups. Pathological examination revealed no lesions compatible with known side effects of NSAIDs. Trabecular bone microarchitecture and growth plate morphology did not differ between the two groups. The findings of this in vivo study reduce concerns regarding the long-term use of meloxicam in young, growing piglets.

EMA and EFSA Joint Scientific Opinion on measures to reduce the need to use antimicrobial agents in animal husbandry in the European Union, and the resulting impacts on food safety (RONAFA)

EFSA and EMA have jointly reviewed measures taken in the EU to reduce the need for and use of antimicrobials in food-producing animals, and the resultant impacts on antimicrobial resistance (AMR). Reduction strategies have been implemented successfully in some Member States. Such strategies include national reduction targets, benchmarking of antimicrobial use, controls on prescribing and restrictions on use of specific critically important antimicrobials, together with improvements to animal husbandry and disease prevention and control measures. Due to the multiplicity of factors contributing to AMR, the impact of any single measure is difficult to quantify, although there is evidence of an association between reduction in antimicrobial use and reduced AMR. To minimise antimicrobial use, a multifaceted integrated approach should be implemented, adapted to local circumstances. Recommended options (non-prioritised) include: development of national strategies; harmonised systems for monitoring antimicrobial use and AMR development; establishing national targets for antimicrobial use reduction; use of on-farm health plans; increasing the responsibility of veterinarians for antimicrobial prescribing; training, education and raising public awareness; increasing the availability of rapid and reliable diagnostics; improving husbandry and management procedures for disease prevention and control; rethinking livestock production systems to reduce inherent disease risk. A limited number of studies provide robust evidence of alternatives to antimicrobials that positively influence health parameters. Possible alternatives include probiotics and prebiotics, competitive exclusion, bacteriophages, immunomodulators, organic acids and teat sealants. Development of a legislative framework that permits the use of specific products as alternatives should be considered. Further research to evaluate the potential of alternative farming systems on reducing AMR is also recommended. Animals suffering from bacterial infections should only be treated with antimicrobials based on veterinary diagnosis and prescription. Options should be reviewed to phase out most preventive use of antimicrobials and to reduce and refine metaphylaxis by applying recognised alternative measures.

A Review of Pain Assessment in Pigs

There is a moral obligation to minimize pain in pigs used for human benefit. In livestock production, pigs experience pain caused by management procedures, e.g., castration and tail docking, injuries from fighting or poor housing conditions, “management diseases” like mastitis or streptococcal meningitis, and at parturition. Pigs used in biomedical research undergo procedures that are regarded as painful in humans, but do not receive similar levels of analgesia, and pet pigs also experience potentially painful conditions. In all contexts, accurate pain assessment is a prerequisite in (a) the estimation of the welfare consequences of noxious interventions and (b) the development of more effective pain mitigation strategies. This narrative review identifies the sources of pain in pigs, discusses the various assessment measures currently available, and proposes directions for future investigation.

Physiological and nonphysiological indicators of body condition score in weaner pigs

The aim of this study was to identify parameters that may be used as objective measures of wellbeing in weaner pigs on farm. Eighty-six weaner pigs were categorized into 3 groups based on their BCS: very compromised (VC, BCS = 1), moderately compromised (MC, BCS = 2), or healthy (HY, BCS ≥ 3). Nonphysiological and physiological measures were then collected from the pigs. Nonphysiological measures included 3 subjective binary scores that assessed the activity, hairiness, and responsiveness of each pig. Physiological measures included rectal temperature, skin temperature, and 11 blood-based parameters. Each physiological measure was assessed in a ternary manner, with pigs being classed as being above, below, or within the normal physiological range. Fisher’s exact tests (FET) were used to identify differences between the numbers of pigs in each BCS category for each variable, and ANOVA of physiological measures was also conducted. Correlations between all variables were also conducted. The FET results identified significant differences for 8 of the measures, with activity, hairiness, responsiveness, rectal temperature, and blood concentrations of glucose, creatinine kinase (CK), albumin, and globulin all differing significantly (all P < 0.05) according to category. Rectal temperature, glucose, and globulin concentrations were significantly different in ANOVA analyses. Of these measures, there were significant correlations between hairiness, rectal temperature, and glucose (all R > 0.30 and P < 0.05). Based on these results, rectal temperature, glucose, and hairiness all warrant further investigation as simple to apply, on-farm measures that can be used in conjunction with body condition and subjective assessment to aid management decisions on pig welfare.

Attitudes of farmers and veterinarians towards pain and the use of pain relief in pigs

A survey of UK-based pig farmers and veterinarians was conducted, in order to investigate attitudes to pain and the use of pain relief in pigs. Survey respondents were asked to indicate which anti-inflammatory drugs they used or prescribed for pigs, how often these were administered, and the level of pain they associated with particular conditions. The survey found that veterinarians used a range of anti-inflammatory products to treat pigs with lameness. While both farmers and veterinarians gave similar pain scores overall, farmers rated gastrointestinal disease as more painful and conversely veterinarians scored lameness higher. Female and younger respondents gave higher pain scores than males and older respondents. Overall, farmers and veterinarians had a positive attitude towards pain relief in pigs with the majority agreeing that animals recovered more promptly when pain relief was administered. Most farmers agreed that the recognition and management of pain is an important part of pig husbandry, and many expressed an interest in finding out more about identifying pain in this species as well as the treatment options available. The study highlighted potential barriers to the increased application of pain relief in pigs in that almost one-third of veterinarians and two-thirds of farmers did not agree that they discussed pain management with each other, while other respondents indicated that they found it difficult to recognise pain in pigs, and did not know how to treat it appropriately.