Accounting for Variation in Your Pig Population
What is the variation in ADG, FG and Carcass Characteristics between my first pull pigs and my cleanout? How does this affect my profits?
Variation is something we will never get away from when raising pigs. Even pigs from the same litter show variable size, health and ability to cope with stress. Pigs across a population grow at various rates and we are used to seeing this growth performance and economic return in an averaged form after all animals have been shipped. When looking at killsheets the money earned per pig is not necessarily that much different for earlier pigs but the margin over feed cost (MOFC) certainly is. This is because first pull pigs are the fastest growing and most efficient animals in the barn. Last pull pigs are typically a mixed bag of animals; some are simply slower growing gilts that have excellent yields and carcass traits while others are just poor doing pigs that need extra time to fill out and may never actually make the grade.
In the table below you can see the dramatic difference in growth performance between first pull and last pull pigs. While the carcass traits are not overwhelmingly different the growth performance and economics are worlds apart.
This shows us that when dealing with populations of pigs we need to pay attention to the variation within the population and understand how we account for it when growing and marketing animals.