How Fast Does S. zooepidemicus Invade The Body After Exposure? By Ed Metzger from South West Ontario Veterinary Service

Jun 03, 2024

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) has emerged as a significant pathogen in pigs, now ranked as the second most serious bacterial disease on the Swine Health Information Center (SHIC) bacterial disease matrix. Disease outbreaks, while infrequent, can cause high mortality and abortions, with recent severe cases reported in the Netherlands and Germany.

Canadian researchers conducted a study to investigate the early stages of S. zooepidemicus infection in pigs following oronasal inoculation.

Study Details:

Inoculation: Fourteen pigs were inoculated with live cultures of S. zooepidemicus ST-194.
Monitoring Intervals: Pigs were monitored at 2, 4, 8, and 24 hours post-inoculation.
Post Mortems: Performed to assess gross visible lesions and collect samples for bacterial culture and PCR analysis at each time point.

Key Findings:

Detection in Organs:
- S. zooepidemicus was detectable in various organs, including the liver and spleen, as early as 2 hours post-inoculation.
Tonsillar Samples:
- S. zooepidemicus was consistently identified in tonsillar samples throughout the study.
Mesenteric Lymph Nodes:
- S. zooepidemicus was commonly identified within mesenteric (intestinal) lymph nodes.
Rapid Spread:
- The spread of S. zooepidemicus to internal organs was quite rapid, consistent with field reports of animals appearing healthy in the morning and becoming critically ill or dead within hours.
Epidemiological Sampling:
- Tonsillar samples could be used for epidemiological sampling and diagnostics.
Persistence and Shedding:
- Finding S. zooepidemicus within mesenteric lymph nodes suggests persistence of infection, replication, and potential shedding. Further research is needed to confirm these conclusions.

Submitted by Ed Metzger, DVM
Ref: Arthur Nery Finatto, Sulove Koirala, Fernanda Luiza Facioli, Jéssica Aparecida Barbosa, Roman Nosach, Matheus de Oliveira Costa. Organ distribution and early
pathogenesis of Streptococcus equi subsp. zooepidemicus in swine. Comp Immunol Microbiol Infect Dis . 2023 Nov 18:104:102095. doi: 10.1016/j.cimid.2023.102095.
Online ahead of print.

Click here to see more...

Video: Evolution of Beef Cattle Farming

The Clear Conversations podcast took to the road for a special episode recorded in Nashville during CattleCon, bringing listeners straight into the heart of the cattle industry. Host Tracy Sellers welcomed rancher Steve Wooten of Beatty Canyon Ranch in Colorado for a wide-ranging discussion that blended family history and sustainability, particularly as it relates to the future of beef production.

Sustainability emerged as a central theme of the conversation, a word that Wooten acknowledges can mean very different things depending on who you ask. For him, sustainability starts with the soil. Healthy soil produces healthy grass, which supports efficient cattle capable of producing year after year with minimal external inputs. It’s an approach that equally considers vegetation, animal efficiency, and long-term profitability.

That philosophy aligned naturally with Wooten’s involvement in the U.S. Roundtable for Sustainable Beef, where he served as a representative for the Colorado Cattlemen’s Association. The roundtable brings together the entire beef supply chain—from producers to retailers—along with universities, NGOs, and allied industries. Its goal is not regulation, Wooten emphasized, but collaboration, shared learning, and continuous improvement.