Breeding and Reproduction

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This page presents sources of information related to efficient reproductive management for swine enterprises.

Pelvic Organ Prolapse project (POP)

Sow mortality, specifically as the result of pelvic organ prolapses, has significantly increased in recent years in the U.S. swine industry. This epidemic sow welfare and production issue is widely acknowledged among producers, academia and allied swine industry partners as it persists and continues to worsen. The recent increase in prolapses has been reported across different regions, frustrating producers and veterinarians alike primarily due to lack of mitigation strategies, or even the ability to execute mitigation-based research projects. In 2018, IPIC received funding from National Pork Board to lead an industry-wide effort in identifying specific areas that may be contributing to the increasing incidence of prolapses.

POP project by the numbers

  • 2018 (year)
  • 109 sow farms
  • 400,000+ sows
  • 16 states

Regular reports shared with participants weeks 6-25 of 2018

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Regular reports of the project shared with participants by week 6-25
week 6 week 7 week 8
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week 15 week 16 week 17
week 18 week 19 week 20
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Regular reports shared with participants weeks 26-52 of 2018

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Regular reports shared with participants weeks 1-5 in 2019

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Regular reports of the project shared with participants by week 1-5; final summary
week 1 week 2 week 3
week 4 week 5 Cumulative Project Update
Brief Project Summary    




30 Pigs per Sow per Year (P/S/Y)

Achieving 30 pigs per sow per year is a reproductive efficiency target that has become achievable by many sow farms in the industry. This National Hog Farmer Blueprint issue on Sow Reproductive Efficiency provides information on the topic from national experts.

Individual articles are linked here:

Gilt development

Selecting, managing and developing replacement gilts is key to the success of any sow operation, regardless of size. How replacement gilts are managed from birth through their first lactation can have marked implications on productivity the remainder of their life.

Gilt selection is a critical component of improving the reproductive efficiency of a sow herd. Identification of gilts with reduced age at puberty is valuable as it is an indicator of sow lifetime productivity.  ISU data indicate that follicular activity, assessed by differences in the size of the gilt’s vulva, prior to puberty (95 and 115 days of age) may have some predictive value for age of puberty onset. These results are in the Iowa State University Animal Industry Report, Identification of Measures Predictive of Age at Puberty (AS 659)

Posters for gilt management and selection:

Sow Lifetime Productivity (SLP)

Sow Lifetime Productivity (SLP) refers to the number of quality pigs a sow weans over her lifetime.  A variety of management approaches from the neonatal stage through first lactation can contribute to SLP. This National Hog Farmer Blueprint issue on SLP highlights the importance of several different production stages.

See individual articles:

Troubleshooting reproduction problems

More swine reproduction resources


Questions? Contact an IPIC specialist

Jason RossJason Ross



Other ISU specialists


Russ Euken
Colin Johnson
Matt Romoser
David Stender
Mark Storlie




Questions? Contact