The Combination of Serum and Oral Fluid Cortisol Levels and Welfare Quality Protocol® for Assessment of Pig Welfare on Intensive Farms

Abstract

Animal welfare is important; therefore, veterinarians and other animal welfare experts try to use different tools for pig welfare assessment. Several welfare protocols are available for pig welfare assessment, and one of the most used is Welfare Quality (WQ) protocol®. Elevated values of cortisol can be indicative of stress and, therefore, poor welfare. Our aim was to assess the correlation between serum cortisol levels from individual samples and oral fluid cortisol levels in group samples with the grades received for pig welfare using the WQ protocol®. Samples were taken at six different commercial pig farms. Animals were divided into age-dependent categories: 5 weeks old (w/o); 7 w/o; 9 w/o; 11 w/o weaners; fatteners; and breeding sows (10 pigs/category). Cortisol was determined in individual sera and group samples of oral fluid (OF), and was compared to values considered to be physiological. Based on WQ protocol® answers, five farms’ welfare level was deemed acceptable, and one was enhanced. Four out of 29 sera and 5 out of 30 OF samples were considered physiological, while in most other samples it was elevated. The correlation between cortisol levels in sera, OF, and WQ protocol® scores was not statistically significant. The cortisol level in OF should be just one of the welfare indicators, i.e., alongside the WQ protocol® filled out by a welfare expert.