Second Litter Drop

August 2004

By Mark White BVSc DPM MRCVS

NADIS Pig Disease Focus

Second Litter Drop

The syndrome termed “second litter drop” refers to the fall off in reproductive performance in sows being bred for their second litter and can be the cause of considerable production shortfalls within a herd. It may manifest in a number of ways but all have a common cause. The following may be seen:

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  Second litter size (born alive) less than the previous (gilt) litter.
  
  
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  Delayed weaning to service interval in weaned gilts.
  
  
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  Reduced conception and farrowing rates in second litter sows compared to the rest of the herd.

Clearly, accurate analytical records are needed to identify any of these features as being specific to this class of sows. Without such records, it is impossible, for instance, to properly investigate a low herd litter size problem.

The root of all these problems relates to the workload done by the gilt during her lactation and clinical inspection may reveal a marked loss of condition between farrowing and weaning. The difficulty arises because:

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  Lactation creates very high nutrient demand.
  
  
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  The young gilt is also still growing and, this also has a nutrient demand.
  
  
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  Gilts appetite during lactation may be limited compared to sows.
  
  
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  Gilts are often used as foster mothers to take extra piglets because the udder is likely to be complete.

To minimise the drain on resources of the gilt during lactation, the following points should be addressed:

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  Do not get gilts in too good (fat) condition at farrowing. This will suppress appetite further.
  
  
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  Once farrowing is completed, reduce room temperature to 18-20°C, dependent upon piglet creep arrangements but avoid creating draughts.
  
  
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  Gradually build-up feed levels over a 10-14 period with no pre-set maximum.
  
  
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  Increase feed intake by:
  • Feeding 3 times daily ensuring at least a 6 hour interval between feeds.
  • Supply ad libitum feeding after 5-7 days.
  • Make a second round of feeding 20-30 minutes after the main feed and supply an extra 0.5-1kg food for any gilt (or sow) that has eaten up.
  • Add water to the food via a hosepipe or bucket – appetite increases on wet food, particularly if food is in meal form rather than pelleted.
  
  
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  Limit the number of piglets sucking on a gilt.  Where problems occur, it helps to restrict gilts to suckling less than 10 piglets in the second half of a 4 week lactation.
  
  
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  Do not extend lactation length for gilts e.g. by using them as a late foster sow.
  
  
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  At weaning, do not mix weaned gilts with big old sows that will bully them away from food.  Pen weaned gilts separately.

While every effort is made to ensure that the content of this forecast is accurate at the time of publication, NADIS cannot accept responsibility for errors or omissions. All information is general and will need to be adapted in the light of individual farm circumstances in consultation with your veterinary surgeon

Copyright © NADIS 2002