Plasma cortisol and behaviour in early weaned piglets
Worsaae, H.; Schmidt, M.
Acta Veterinaria Scandinavica 21(4): 640-657
1980
ISSN/ISBN: 0044-605X PMID: 7223585 Document Number: 168114
Comparisons were made of cortisol concentration and behavioral activity beween piglets weaned at 3 wk of age (early weaned piglets), and piglets weaned at 8 wk of age (control piglets). Early weaned littermates were placed in cages with a floor area of either 0.20 m2/piglet or 0.15 m2/piglet. At 8 wk of age, the piglets in the control litters were moved from the sow and early weaned piglets were moved from the cages. All litters were placed in pens, 1 pen/litter. Radioimmunoassay was used for plasma cortisol determination. Behavioral activity included determination of play, aggressive behavior and non-nutritive oral activity. Statistical analysis for possible association between plasma cortisol concentration and age, housing conditions, litter and sequence of capture of littermates for blood collection revealed a complex pattern. Generally, higher plasma cortisol concentrations and more aggressive and non-nutritive oral activity, but less paying activity, were associated with early weaning. Plasma cortisol concentration in individual piglets was positively correlated to both aggressive and non-nutritive oral behavior, but was negatively correlated to playing behavior. Early weaning apparently is a stressor.