SWINE

Graph outlining most frequent PRRS types

Swine abortion/mummification/stillbirth diagnostic work-up  

Josepha DeLay

A 3-fold increase in swine abortion / fetal mummification / stillbirth submissions from April-June 2016 has been identified at the AHL. For evaluation of these cases, submission to the diagnostic laboratory of 3 fetuses and placentas from 3 separate litters is ideal. Infectious agents or lesions may not be present in all fetuses, and evaluation of multiple fetuses from multiple litters increases the likelihood of reaching a useful diagnosis. Submission of live-born but weak neonates is also helpful.

Serum samples from 3-5 aborting / affected sows and an equal number of unaffected cohorts is also useful. Sera provide the best means for diagnosing leptospirosis and PRRSV-related abortions. In cases for which routine tests do not identify the cause of abortion, sera may be valuable in identifying new or emerging pathogens.

Bacterial culture, PCR for PRRSV/PCV-2/PPV, fetal Leptospira serology, and histopathology will be carried out on pooled samples from the fetuses.

If sampling on-farm or in-clinic, both formalin-fixed and fresh (chilled) fetal tissue samples should be collected and forwarded to the diagnostic lab, as follows:

  • Fresh samples (from each fetus – for microbiology, including PRRSV, PCV-2, and PPV PCR; bacterial culture; leptospira serology): Thoracic fluid (aseptically aspirated), stomach content (aseptically aspirated), lung (2 samples), thymus.
  • Samples in formalin (from each fetus - for histopathology): eyelid (including conjunctival surface), tonsil, thymus, lung, thyroid gland, heart, liver, spleen, kidney, adrenal gland, colon, brain, placenta.
  • Serum samples from affected sows and unaffected cohorts.