Longevity as a female trait has several different definitions. Each definition has a somewhat different interpretation, depending on the intent. Some definitions are based more on production efficiency while others are more time dependent.
The makeup of the litter a female is born into and how she performs through development can impact her subsequent longevity. In addition, the number of pigs within her first litter also significantly influences her survival risk.
This study has demonstrated that identifying which factors impact longevity depends somewhat on the definition. Thus caution should be used when interpreting what factors influence longevity and thus what possible management changes or policy decisions are needed, since which factors influence longevity is dependent on what definition is used to define longevity.