Two batches of sows and piglets will be sampled longitudinally at multiple body sites by De Varkenspraktijk. DASS-specific qPCR assays will be performed by WBVR and BioChek, and associations between alternative sample types and tonsil swabs will be analyzed at multiple timepoints, including comparison of pen-level versus individual sampling sensitivity. Results will inform the diagnostic value of alternative sampling sites for accessible herd-level DASS screening. Findings will be disseminated through farming magazines, veterinary networks and peer-reviewed publication. A sector-wide workshop (combined with LVW24101) will reach farmers, veterinarians, researchers, and industry partners, ensuring broad uptake and supporting improved diagnostics to reduce S. suis disease burden and antibiotic use.

Goal

This project focuses on improving diagnostics for Streptococcus suis (S. suis) in pigs. S. suis is an important porcine pathogen capable of causing severe disease, including meningitis, septicaemia, and arthritis, particularly during the nursery phase between 4 and 10 weeks of age. S. suis is endemic in pig populations, and most animals carry the bacterium in the upper respiratory tract, including the tonsils and nasal cavity. Under certain conditions, S. suis can breach the mucosal barrier and translocate to the bloodstream and tissues, resulting in invasive disease. The precise mechanisms underlying this transition from colonisation to invasion remain incompletely understood; identified risk factors encompass bacterial, host, and environmental components. Given the severity of clinical signs, S. suis disease exerts a substantial impact on the health and welfare of piglets. Effective therapeutic and preventive measures remain limited, with current options largely confined to antibiotic treatment and autogenous vaccination, the latter with variable efficacy. Previous PPP research (LWV201041) demonstrated that S. suis disease is one of the most important drivers of antibiotic use in weaned piglets. Additionally, certain S. suis strains are zoonotic and capable of causing severe infections in humans.

The aim of this project is to compare DASS abundance across several accessible sample types and to benchmark these against tonsil swabs as the reference standard. Direct comparison of results across sampling methods will provide the scientific foundation for potentially adopting alternative approaches — such as saliva sampling — for herd-level DASS surveillance. This would offer veterinarians and farmers a more practical and animal-friendly means of screening herds for DASS carriage and applying DASS-specific interventions, with as ultimate goal to lower the burden of S. suis disease and antibiotic usage.

The main research questions to be addressed are:

What is the correlation/association in DASS prevalence/presence between sample types?
Does this change over time as the animals age (i.e., is this a stable relationship)?
How does the sensitivity of group-level (pen) sampling compare with that of individual sampling from the same pen?

Partners and their specific tasks in the project:

De Varkenspraktijk is a large collective of veterinarians that are closely connected to the veterinary problems that occur on pig farms. They support pig farmers on a daily base and will have valuable insight into the problems that occur in the field.
Varkenspraktijk is main applicant (‘penvoerder’). Varkenspraktijk will perform sampling and collect metadata of the sampled animals on the farm. Varkenspraktijk will disseminate results of this study to other vets.
BioChek is a biotech company that provides an accurate, reliable and easy-to-use animal health monitoring system for the poultry and swine industry with a strong interest in disease.
BioChek will perform DASS-specific qPCRs on different sample types to compare their diagnostic value.
WBVR is a research institute and part of WUR focusing on combatting infectious diseases in livestock, with over >30 years of experience in research. WBVR will act as project coordinator and perform research tasks to answer the research questions of the project.
WBVR will aliquot and store the samples, perform DNA isolations, and perform DASS-specific qPCRs on different sample types. qPCR results will be analyzed to determine the association of DASS presence in the alternative sample types compared to tonsil swabs.

Towards Practical and Animal-Friendly Herd Screening for Pathogenic S. suis (MKB26002)

Projectstatus

Lopend

Looptijd

Projectregeling

Pilot Innovatief MKB