Rope-based oral fluid sampling for early detection of classical swine fever in domestic pigs at group level

Abstract

BackgroundNon-invasive sampling techniques based on the analysis of oral fluid specimen have gained substantial importance in the field of swine herd management. Methodological advances have a focus on endemic viral diseases in commercial pig production. More recently, these approaches have been adapted to non-invasive sampling of wild boar for transboundary animal disease detection for which these effective population level sampling methods have not been available. In this study, a rope-in-a-bait based oral fluid sampling technique was tested to detect classical swine fever virus nucleic acid shedding from experimentally infected domestic pigs.ResultsSeparated in two groups treated identically, the course of the infection was slightly differing in terms of onset of the clinical signs and levels of viral ribonucleic acid detection in the blood and oral fluid. The technique was capable of detecting classical swine fever virus nucleic acid as of day 7 post infection coinciding with the first detection in conventional oropharyngeal swab samples from some individual animals. Except for day 7 post infection in the “slower onset group”, the chances of classical swine fever virus nucleic acid detection in ropes were identical or higher as compared to the individual sampling.ConclusionsWith the provided evidence, non-invasive oral fluid sampling at group level can be considered as additional cost-effective detection tool in classical swine fever prevention and control strategies. The proposed methodology is of particular use in production systems with reduced access to veterinary services such as backyard or scavenging pig production where it can be integrated in feeding or baiting practices.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-016-0930-2) contains supplementary material, which is available to authorized users.

Detection of Antibodies against Mycobacterium bovis in Oral Fluid from Eurasian Wild Boar

“…Instead, ropes can be placed in the area frequented by wild boar, taking advantage of their natural chewing behavior. The ropes have been found to be attractive to wild boar, especially in areas with resources or supplementary food, facilitating OF collection [42]; (2) samples are easier to collect-therefore the metod is less stressful (welfare-friendly)-transport, and store; therefore, (3) this technique can be directly applied in field conditions, facilitating the implementation of surveillance and eradication measures [43].…”

Classical Swine Fever—An Updated Review

“…Sampling can be the bottleneck of swine fever diagnosis, especially in the case of wild boar, but also in remote areas. For this reason, alternative sampling strategies and sample matrices have been tested for CSF (often combined with African swine fever sampling) especially for wildlife specimens and under rural conditions [ 209 , 210 , 211 , 212 ]. However, most of them are not yet in routine use and need further validation.…”

Guidelines for oral fluid-based surveillance of viral pathogens in swine

“…In free range animals, oral fluids have been collected using "samplers" consisting of short lengths (~10 cm) of rope embedded with a cereal-based bait matrix. Investigators have reported that the animals chewed the samplers, dropped them on the floor, and the next pig repeated the process, thereby providing an "aggregate" specimen [44,65]. Under experimental conditions, this approach provided for better CSFV or FMDV nucleic acids detection than oropharyngeal, nasal, or buccal swabs [44,65,88].…”