Welfare indicators associated with feed conversion ratio and daily feed intake of growing-finishing pigs

Abstract

Context Understanding the welfare indicators that affect animal performance can facilitate modifications that improve both animal welfare and profitability. Aims A cross-sectional study was conducted to investigate the prevalence of animal welfare indicators and quantify their possible associations with feed conversion ratio (FCR) and daily feed intake (DFI) of growing-finishing pigs (Sus scrofa). Methods Data from 46 farms were collected. The herds ranged from 360 to 2500 pigs, which were aged between 75 and 173 days, and were managed on an all-in all-out basis. The welfare indicators were evaluated once on each farm using the methodology of the Welfare Quality® assessment protocol for pigs. Multiple linear mixed models were used to assess the associations of welfare with FCR and DFI according to the production stage at which the pigs were evaluated on the farm. Key results The welfare indicators with the highest average prevalence were frequency of coughing (35.7%), moderate bursitis (31.1%), and moderate and severe soiling with manure (18.8 and 27.7% respectively). Most of the remaining indicators related to poor welfare had prevalence values of less than 1%. The mean prevalence of positive social behaviour (such as sniffing/nosing/licking) was 14.4% and that of negative social behaviour (NSB; such as aggressive interactions) was 3.1%. The average space allowance (measured in 460 pens) was 1.04 ± 0.13 m2/pig (ranging from 0.78 to 1.36 m2/pig). Better FCRs were associated with a low prevalence of NSB (P < 0.05), a low prevalence of coughing (P < 0.01), absence of lameness problems (P < 0.001), and small space allowances (P < 0.05). Lower DFI values were associated with a low prevalence of NSB (P < 0.05), a high prevalence of moderate hernias (P < 0.01), a low prevalence of other active behaviours (such as eating and drinking) (P < 0.001), and a high prevalence of animals with wounds on the body (P < 0.05). Conclusions Few indicators related to the impairment of welfare were detected with a high prevalence, and the results suggest that the conditions related to poor welfare were associated with an impairment in animal performance. Implications The results of this study can provide the industry with comparative information to promote improvements in pig welfare. Some welfare indicators could be used on farm as predictors of performance variables; however, these indicators need validation.