The one concept many schools do not teach about swine production

nutrition series swine nutritionist swine production swine students Jun 25, 2021

Here is the one concept that I wish most schools would teach swine industry professionals: space long and space short.

Space long or space short has to do with how is the pig flow from the production system?

Do we need to market the pigs as soon as possible because the nursery pigs are coming? That would mean the production system is space short.

Or, we do not need to rush too much; we can leave the finishing pigs a few days more in the barn to reach target weight since the nursery pigs are not coming in until a few weeks from now? That would be space long.

Space short is also known as fixed time

  • Most production systems, most of the year, will be space short
  • The best example of being space short is when pigs reduce feed intake and grow slower in the summer.
  • A short downtime (no downtime to a few days) is typical when you are space short.
  • ADG and F/G are important: what happens here is what we call “the value of gain”. Basically, every extra pound or kg of body weight gained in that fixed amount of time will increase the market value of the pig. On the other hand, if you were space long, you could leave the pigs in the barn a few days (or weeks) longer to reach their target market weight (fixed weight scenario).

Space long is also known as fixed weight

  • Not as common as space short, but a excellent example of that is during the winter time where pigs have increased feed intake and growth, being ready to market faster.
  • If the production system has a few weeks of downtime between close-outs is an indication that it is likely space long.
  • F/G is essential but the “value of gain” that you observe on a fixed time scenario does not happen here because it is cheaper to leave the pigs in the barn a few more days ($0.14 per pig per day) than to increase diet density.



Dr. Marcio Gonçalves


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