|Rault, Jean-loup - Purdue University|
|Carter, Sue - University Of Illinois|
|Garner, Joseph - Purdue University|
|Richert, Brian - Purdue University|
|Lay, Jr, Donald - Don|
Submitted to: International Society of Applied Ethology
Publication Type: Abstract Only
Publication Acceptance Date: 4/16/2011
Publication Date: 7/4/2011
Citation: Rault, J., Carter, S., Garner, J., Marchant Forde, J.N., Richert, B., Lay Jr, D.C. 2011. Oxytocin reduces separation distress in piglets when given intranasally. International Society of Applied Ethology. Proceedings ISAE.
Technical Abstract: Oxytocin (OT) is one of the neurobiological foundations of sociality. It acts as a neuropeptide in numerous social processes, from ultra-social to anti-social behaviors. Evidence supports a role for OT in social support, possibly by attenuating separation distress. Nonetheless, research on OT is lacking in our effort to understand social behaviors of domestic animals and implement practices that meet their social and psychological needs. Separation from conspecifics is particularly stressful to social animals, especially prior to weaning. Here, we tested the hypothesis that OT administered intranasally could reduce social separation distress of suckling piglets. At 13 days of age, across 6 litters, 12 piglets received 0.25 mL (24 IU i.e., 50 µg) of OT intranasally (OT) while 12 littermates received 0.25 mL of saline (SAL), balanced by gender. At 45 min after treatment, each piglet was fitted with a telemetric heart rate belt and placed in an isolation box for 15 min. Behaviors, vocalizations and heart rate were recorded during the test and blood was sampled 24 hr before, right after, and 30 min after the test to measure cortisol concentrations. Results were analyzed using a mixed model in SAS. Oxytocin piglets displayed reduced locomotor activity (P=0.02), explored less (P=0.03), spent more time lying (P=0.02) and inactive (P=0.03) than SAL piglets. They also tended to emit fewer grunts and escape attempts (both P<0.1) compared to SAL piglets. Some responses were sexually dimorphic (P<0.05 to 0.1), with females responding stronger than males to OT, possibly due to an estrogen influence. Cortisol concentrations did not differ between treatments (P>0.1). Our results support the hypothesis that OT given intranasally can modify behavior, possibly through direct effects on the nervous system. This is the first evidence that OT is able to attenuate social separation distress in farm animals. It is possible that OT is naturally released in the presence of conspecifics, resulting in effects similar to those seen in this study. If high concentrations of OT relates to a positive social environment, OT could constitute one of the first positive indicators of social needs and welfare.