Relationship between LP5~(TM) and litter uniformity and birth weight

摘要

Selection programs have histotically, and in many current instances, focused on improving total number of pigs born in a litter. Phe-notypic and genetic relationships between large litter size and pig birth weight and survival are undesirable meaningthat as litter size increases in a population, the mean pig birth weight and survival rate decreases resulting in a diminishing return to improving litter size. Altering a selection program to improve litter size and pig quality at the same time can offset these negative effects. Changing the selection emphasis to "Live pigs at day 5"~(TM) (LP5~(TM)) and measuring the component trait of pig birth weight have proven to be effective methods to capture the full value of improved litter size.