Gamma-aminobutyric acid (GABA) is a bioactive amino acid with anti-inflammatory and neurotransmitter properties, yet limited information exists regarding its production by Lactiplantibacillus paraplantarum. We evaluated factors that influence GABA synthesis by L. paraplantarum HK-1 and assessed its production in vitro and under simulated gastrointestinal conditions. GABA production was analyzed using HPLC with pre-column derivatization, gene expression was assessed through RT-qPCR, and probiotic characteristics were evaluated using standard microbiological methods. L. paraplantarum HK-1 demonstrated dose-dependent GABA production with monosodium glutamate (MSG) supplementation, achieving maximum levels at 500 mM MSG (161.1 µg/mL), which was significantly higher than those in other treatments (p < 0.01). A strong positive correlation was observed between MSG concentration and GABA production (r = 0.908, p = 0.002). Gene expression analysis revealed a 61.6-fold higher gadB expression at 500 mM MSG compared to 250 mM, though statistical significance with GABA production was not achieved (r = 0.741, p = 0.259). The strain exhibited appropriate probiotic characteristics including γ-hemolytic activity, bile salt tolerance, and acid resistance. Under simulated gastrointestinal conditions, maximum GABA production occurred in the distal colon (148.3 ± 19.0 µg/mL with probiotic vs. 7.2 ± 6.2 µg/mL control), with overall production significantly higher in probiotic-treated groups (p < 0.001). Overall, L. paraplantarum HK-1 produced GABA throughout gastrointestinal phases and showed traits consistent with probiotic use. These results position HK-1 as a promising GABA-producing candidate for functional food applications, pending in vivo validation.

Porcine reproductive and respiratory syndrome (PRRS) is an endemic disease affecting the swine industry. The disease is caused by the PRRS virus (PRRSV). Despite extensive biosecurity and control measures, the persistence and seasonality of the virus have raised questions about the virus’s environmental dynamics during the fall season when the yearly epidemic onset begins and when crop harvesting and manure incorporation into the field occur. Therefore, this study aimed to assess the potential for PRRSV to percolate through different soil types, simulating conditions that could lead to groundwater contamination which could represent a risk of herd introduction. An experimental soil column model was used to mimic field conditions. Three PRRSV-2 strains were tested across thirteen Minnesota soils with different physical and chemical characteristics. The findings revealed that PRRSV can percolate through all soil types and that the amount of virus percolated decreases with increased amounts of soil. These results suggest that PRRSV can percolate through different soil types. Further investigations should be undertaken to determine the associated implications for swine health and biosecurity measures.

Porcine reproductive and respiratory syndrome (PRRS) causes significant economic losses and is a major challenge to the swine industry. The PRRS virus (PRRSV) has high rates of mutation and evolution. We examined the influence on ORF5 Sanger sequencing outcomes of various concentrations of a wild-type (WT) PRRSV (lineage 1A RFLP 1-7-4) and a modified-live vaccine (MLV) virus (lineage 5 RFLP 2-5-2) in the same sample. Vaccine-like sequences were detected more frequently than the WT virus when the MLV virus was present at equal or higher concentrations than the WT virus. This result suggests that ORF5 Sanger sequencing may preferentially detect the dominant virus in samples containing more than one virus, potentially masking WT viral infections in vaccinated herds. Although our findings highlight a limitation in identifying co-circulation of strains, Sanger sequencing is still widely used as an accessible tool to characterize PRRSVs. Advanced sequencing techniques, such as NGS or CLAMP-based approaches, would complement Sanger sequencing results and allow improved detection of co-circulating variants by minimizing consensus sequence bias and selectively blocking vaccine-like sequences.