The “Real Welfare” scheme: Identification of risk and protective factors for welfare outcomes in commercial pig farms in the UK

Abstract

From 2013-2016, animal-based measures were collected as part of the "Real Welfare" protocol adopted by the Red Tractor Pigs Assurance Scheme to assess the welfare in finisher pig herds in the UK. Trained veterinarians from 89 veterinary practices assessed 112,241 pens (hospital pens excluded) from 1928 farms using a multistage sampling protocol, and collected data about pig welfare, management and farm environment. Multivariable analyses were conducted for five main welfare outcomes: lameness, pigs requiring hospitalization, severe tail lesions, severe body marks and enrichment use ratio (number of active pigs interacting with the enrichment/total number of active pigs). Additionally, a multiple correspondence analysis (MCA) was conducted to analyse systematic patterns of variations of environmental characteristics and improve understanding of the connection between welfare outcomes and environment. The prevalence of the four welfare outcomes and the mean enrichment use ratio differed between pen types (P<0.05), with a higher mean prevalence of lame pigs (0.39%) but lower mean prevalence of pigs requiring hospitalization (0.07%), severe tail lesions (0.07%) and severe body marks (0.12%) in outdoor pens. In&outdoor pens had the highest mean prevalence of the measured outcomes (P<0.05). After adjusting for the farm, date and pen type, lameness, pigs requiring hospitalization and severe tail lesions were less prevalent in large pens (P<0.01), pens with substrates (P≤0.05) and pens fed with meal (P≤0.05), while enrichment use ratio was higher with substrates (P<0.001). Moreover, pigs requiring hospitalization and severe body marks were more prevalent in pens with powered ventilation (P<0.05). On the MCA graph, higher prevalences of lameness and pigs requiring hospitalization (>1, 5 and 10%) were located in the same direction as lower enrichment use ratio, liquid feed, trough feeding, floor feeding, restricted feed and in&outdoor pens. Results suggested that higher prevalences were not specifically connected to a particular system, but that all welfare outcomes were connected to several inappropriate features in the environment. This study highlights individual risk factors which can be considered to improve animal welfare, but also indicates the need to consider the environment as a whole because of potential factor combinations and confounds. Understanding of these requires a large scale database, which can be drawn from assessments carried out as part of farm assurance and support evidence-based advice and future formulation of standards for good practice.

Connecting Different Data Sources to Assess the Interconnections between Biosecurity, Health, Welfare, and Performance in Commercial Pig Farms in Great Britain

“…The results of correlation coefficients and the PCA were used in combination to understand the interconnection between health, welfare, and performance. Health and welfare indicators used in this study have been described in previous papers ( 18 , 21 , 49 ), and the results for our sample were consistent with these reports. However, several other interconnections between health, welfare, and performance are newly described in the current study.…”

“…The presence of missing values or necessary imputations might impair the data quality and the ability to conduct analysis with the data available. Data about pig health and welfare are regularly recorded by the Real Welfare and BPHS for the purpose of informing farm management decisions and aiding farm improvement, and cover a large majority of the fattening pig farms in Great Britain ( 6 , 18 , 21 ). There is a risk of discrepancies in the data recorded as nationwide data are recorded by several observers.…”

“…There is a risk of discrepancies in the data recorded as nationwide data are recorded by several observers. However, the standardized procedure and the training provided in each scheme were designed to minimize observer bias and were assessed in previous studies ( 18 , 21 ). Our study illustrates the challenge of using secondary data related to the pig industry and highlights the challenges regarding the data collection, the connection of different data sources and the design of a random sampling from the whole population of pig farms which is large enough to be representative of the commercial pig farms in the UK.…”

“…Previous studies have highlighted the connection between different pig pathologies ( 49 ) and different welfare outcomes ( 14 , 21 ). Prevalence of ep and pleuritic lesions were highly correlated in the present dataset; similar risk factors and correlation between ep and pl have been reported in several studies ( 50 – 52 ).…”

The translation of animal welfare research into practice: The case of mixing aggression between pigs

“…1). Data from 1,928 farms in the UK show a prevalence of 0.24% for severe skin lesions (Pandolfi et al, 2017) and 11% for mild body lesions (Real Welfare, 2017), which are a result of aggression.…”