Tech Bulletin

A Potential PED Immune Management Intervention Protocol

A group of practitioners was surveyed to determine their current recommended PED immune management protocol. Each practitioner was asked, “When a farm breaks with PED, what are the steps you have followed?”. This potential protocol was developed from the most common answers from the group.

This protocol is a report of observations and should not replace any recommendations from your herd veterinarian. Please consult with your herd veterinarian before implementing any immune management intervention protocol.

  • Step 1

    Collect samples and send samples for confirmation and identification of pathogen(s).

    • Fresh and fixed samples from pigs with acute diarrhea (less than 36 hours in duration), as well as fecal samples. Request histopathology, IHC and PCR on tissue samples and PCR of fecal samples.
    • If PED PCR is positive, sequence S1 gene.

  • Step 2

    Following confirmation of PED infection, all pigs greater than 10 days of age should be immediately weaned and moved to an offsite location.

  • Step 3

    Load and close the farm to new introductions.

    • If elimination of the virus is the stated goal: Close the farm for at least 150 days.
    • If positive gilts are the replacement source: Close the farm for at least 90 days.

  • Step 4

    Begin feedback of infectious material at the rate of 1 pig source of infectious material to 10 sows (1:10 is the most common, but there are also reports of 1:15 and 1:20).

    • Observe sows daily for clinical signs (diarrhea and inappetance); keep a diary.
    • Continue feedback to all sows not showing clinical signs for the next three days.
    • Repeat feedback to entire herd the second week. The goal is to have greater than 70 percent of all sows showing clinical signs.
    • Some are using aspirin, etc. to help manage the severity of clinical signs during feedback.

  • Step 5

    Begin a farm cleaning and disinfecting protocol.

    • Wash sows (utilizing sow wash soap) prior to entry to farrow and at farrowing exit.
    • Pay scrupulous attention to cleaning and disinfecting of premises and equipment.

    For more information on a sample disinfecting protocol, visit the Reduce Risks page and click on Sanitation.

  • Notes

    • Neonatal pigs have been reported beginning to live about 1–2 weeks after second feedback. Mortality rates should start to decline over the next two weeks until you return to normal preweaning mortality rates.
    • Expect conception rates to be decreased as much as 20–30 percent in the groups of animals that are in the implantation phase during the feedback.
    • Some are using progesterone to extend the gestation period by up to 6 days past card date to delay the arrival of susceptible pigs until the high mortality period has passed.
      • Some are reporting increased stillborns and retained pigs if progesterone used after card date 117
      • Reports of increased vaginal discharge with use of progesterone
    • The early-weaned sows may neither cycle nor breed well. A suggested protocol on managing this situation is below:
      • Sows weaned with greater than 16 days of lactation – move to breeding barn and treat according to early-wean protocols
      • Sows weaned with 9–16 days of lactation – administer progesterone for 10–14 days then give PMSG/HCG to induce ovulation
      • Sows weaned with less than 9 days of lactation – administer progesterone for 17 days, then give PMSG/HCG to induce ovulation