This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.
The Science Page this week is brought to you by researchers Alice Perrucci, Alice Magri, Vanessa Cardana, Simona Zoppi, Claudia Cossettini, and Annalisa Scollo.
Key Points:
- A standardized Cleaning and Disinfection (C&D) protocol can help increase the hygiene status of trucks transporting live pigs
- The boot storage was found to be the most neglected and contaminated spot
Introduction
The road transportation of live pigs represents a critical biosecurity risk for the swine industry. Trucks move between multiple farms and slaughterhouses with different sanitary statuses acting as vectors capable of spreading pathogens across large geographic regions, especially under the current threat of African Swine Fever. Although Cleaning and Disinfection (C&D) is a legal requirement enforced by the European Animal Health Law (AHL), practical compliance suffers from significant regulatory and structural gaps. Consequently, transport personnel often underestimate this sensitive task due to undefined procedures and a lack of evaluation systems. While some private companies implement internal protocols, the scientific community has not yet established universally accepted standards. Since a properly executed C&D process may disrupt the farm-to-farm contact network generated by truck movements, this study aimed to fill these gaps by validating a standardized, multi-phase protocol with practical recommendations for swine industry workers.
Methods
Starting from current legislation for barn C&D, and refining it through available literature, a detailed standardized step-by-step protocol for truck hygiene was developed. Each vehicle was divided into three functional sections: transport unit, boot-storage compartment, and driver’s cabin. The protocol was applied to 15 trial trucks transporting live pigs and compared with 23 market trucks, which served as controls. C&D was assessed across the three functional units through visual inspection, adenosine triphosphate (ATP) testing, and microbiological analyses of environmental samples, including total viable count (TVC) on all trucks.
Results
The trial trucks C&D protocol compared to the control market trucks demonstrates a significant improvement across all assessed parameters. Operatively, the standardized protocol required approximately 2.5 hours for a 130 m² articulated truck, whereas control truck procedures ranged from a rapid 20 minutes to 1 hour, heavily constrained by driver schedules. Visually, trial trucks achieved a significantly higher overall cleanliness score than controls (82.10 ± 9.72% vs. 72.20 ± 7.48%; p = 0.0018), with nearly half of the trial trucks (46.7%) exceeding the 80% cleanliness threshold across all compartments compared to only 4.3% of controls (p = 0.0065). Severe organic residue (visual score ≤ 2) prevented ATP testing in a massive portion of control trucks (e.g., 73.9% in the driver’s cabin and boot storage), whereas trial measurements confirmed excellent sanitization, with the driver’s cabin averaging 27.6 ± 45.1 RLUs (Figure 1). Microbiologically, results further highlighted the protocol effectiveness: trial trucks achieved 100% success in reducing the TVC below the target hygiene threshold (<10 CFU/cm²; average reduction: 2.06 ± 0.70 log₁₀). In contrast, only 33.3% of driver’s cabin swabs, 50.0% of cargo-area swabs, and none of the boot storage samples (p=0.0254) from control trucks met this threshold. Finally, bacteriological testing confirmed that the trial protocol achieved 100% eradication of Methicillin-Resistant Staphylococcus aureus (MRSA) in both environmental swabs (from 100% to 0%; p = 0.0079) and air samples (from 13.3% to 0%).
Discussion
In this study, implementing a standardized, multi-phase C&D protocol markedly improved the sanitary status of pig trucks compared to unstructured commercial practices. A key finding was the effectiveness of combining different assessment methods to identify critical control points for C&D. Visual inspection proved to be an effective, low-cost first-line screening tool. Setting an 80% cleanliness threshold clearly differentiated the trial group (46.7% compliance) from the control group (4.3%). While objective ATP testing was hindered in control trucks due to heavy organic residues, it successfully verified real-time sanitation in trial vehicles. Furthermore, microbiological analysis confirmed that the protocol achieved a strict target of <10 CFU/cm2 in 100% of trial trucks, whereas control trucks failed. Crucially, both TVC and ATP analysis exposed the boot storage area as the most neglected and contaminated site across haulers, representing a major biosecurity weak point for pathogen spread. Conversely, targeted testing showed that the trial protocol eliminated MRSA from environmental and air samples, showcasing its strong potential to combat antimicrobial resistance and reduce occupational exposure for drivers. Despite a longer execution time (2.5 hours), this validated protocol provides crucial, practical guidance to minimize vehicle-mediated disease transmission and improve transport biosecurity.
Full Paper: https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2026.1789484/full
The authors wish to thank Chemifarma S.p.a. for their support.
The study was funded by Contratto di Filiera ABC4 Suini Pink Valley—DM n. 0673777 of 22/12/2021, V Avviso n. 0182458 of 22/04/2022 e s.m.