Relationship between feeding, stereotypies, and plasma glucose concentrations in food-restricted and restrained sows

The primiparous food-restricted sows were investigated as to whether individual differences and/or daily variations in levels of chain manipulation and excessive drinking are correlated to individual differences and/or daily variations in pre- or postfeeding glucose concentrations. Blood samples were taken at regular intervals prior to, during, and after feeding, from sows that had developed stereotypies to different degrees over 110 days of restrictive housing and feeding conditions. Glucose concentrations were low prior to and high after feeding. Levels of stereotypies showed similar variations, suggesting that the performance of stereotypies is not related to low glucose concentrations. Furthermore, whilst sows differed consistently in glucose concentrations, no correlations were found between individual glucose concentrations and stereotypies. Similarly, no correlations were found between glucose concentrations and chain manipulation or drinking on a sample to sample basis. The data show that although performance of stereotypies is strongly dependent on feeding regime, it is not related to plasma glucose concentration.