Date Full Report Received


Date Abstract Report Received



Primary Investigator:


Immune responses of piglets to weaning stress: Impacts of photoperiod
J. Anim. Sci. 2007. 85:93-100.

Photoperiod influences the immune status of multiparous pregnant sows and their piglets.
J. Anim. Sci. 2006. 84(8):2072-87.

Animals adapt more readily to photoperiod cues than other environmental cues since photoperiod is more predictable and consistent over time. Previous work has shown limited (if any) affects of photoperiod on pig physiology and performance. However, these data begin to provide support that photoperiod may potentially be used to manipulate physiology and performance as well as counteract the negative effects of stress. Photoperiod manipulation used at critical points during development may actually influence physiological responses later in life which may ultimately have impact on pig well-being, health and performance. These data provide support that immune responses and performance/productivity of sows, neonates, and young pigs can be influenced by photoperiod. In addition, sex of the piglet also interacts with these factors. It appears that the photoperiod treatment a sow is subjected to may influence early responses of her piglets. More, importantly, photoperiod may potentially provide a management tool that could be used to counteract the negative consequences of weaning stress and other stressors. It is imperative that we understand whether immune stimulation (increased immune responsiveness) is beneficial or detrimental to the challenges that a sow or piglet may encounter throughout production. This question remains to be resolved.