Effects of pasturing on behavior and salivary Cortisol concentrationsin breeding sows

摘要

After being released from confinement and given access to pasture during the daytime, behavioral changes and fluctuations in salivary Cortisol concentrations were observed in seven sows. It was found that while the sows were in the confinement period(days -1to 0)， their resting behavior occupied over 84% of their activity. However, sows increased their moving activity while in the daytime pasture period (days1to 5). The resting behavior reached its minimum value on day 2 and gradually increased from day 4. On the other hand, salivary Cortisol concentration during confinement period did not differ between morning and evening, and it remained at 0.077 to 0.086 ix% I dl.It rises from the evening of the first day of release and shows the highest value(0.293 mug / dl) on the second day morning. The high value lasted until the 4th day and turned to decrease after the 5th day. The salivary Cortisol concentrations in the afternoon on days1and 4 were significantly higher (p < 0.05) than the afternoon values of day 0. Salivary Cortisol concentrations began to decrease on day 5. This implied that the sows adapted to the new environment. The coincidence between the increasing resting time and decreasing Cortisol concentrations on day 5 may suggest a relationship between behavioral patterns and salivary Cortisol concentrations. However, establishingthe exact dynamics of Cortisol requires alonger period of study.