One of the objectives of CWSHIN is to detect new and emerging health issues in the swine sector. Therefore, we want to discuss events with unusual clinical presentations of disease or presence of rare diseases. To detect these events comments made practitioners in the quarterly Clinical Impression Surveys are invaluable.
This quarter we had three good examples.
Streptococcus equii zooepidemicus (Strep zoo) was detected on a farm. Disease caused by Strep zoo is very rare in Canada. It has only been detected on 5 farms in 2019. However, it is severe with sudden deaths, abortions, sows off feed and depressed. Sows may die within 12 hours of the first signs. In this particular case (5000-sow operation) in 7-day period, 69 sows died.
The signs of Strep zoo in a herd are so severe that they can mimic African swine fever (ASF). In this particular case dramatically enlarged spleens were seen in addition to high mortality among sows. Very early on sows responded well to antibiotic treatments therefore, a bacterial infection was suspected and likely.
Therefore, let us be reminded that:
- ASF suspect cases must be reported to CFIA immediately
The Strep zoo case would have been a suspect case if not for the good response to antibiotic treatment
- For cases such as this that is NOT an ASF suspect but with a disease that mimics ASF such as sudden death, internal bleeding and discoloring of the skin an ASF rule-out test should be requested. The steps are:
- Call your herd practitioner if you see the signs
- The practitioner can investigate, submit samples and request ASF rule-out test
Post-weaning multisystemic wasting disease (PMWS) in nursery pigs that failed to thrive or reach market weight was thoroughly investigated by a practitioner. There was compelling evidence that Porcine circovirus 3 (PCV3) may have been the virus involved. Circovirus 2 (PCV2) is known to cause wasting in nursery pigs, but type 3 is relatively new as a cause of disease. For diagnostic and control purposes it is important for all practitioners in the region to keep updated on emerging new strains and share experience on their control. Therefore, sharing such cases through comments in the Clinical Impression Surveys and CWSHIN’s quarterly calls is useful and important.
In a 5000-sow operation, where day-olds were scouring, Sapovirus may have played a role. Historically Sapovirus was not thought to be pathogenic but recently some strains have been thought to cause clinical signs.