Animal feed can be contaminated with fomites carrying swine viruses and subsequently be a vehicle for viral transmission. This contamination may not be evenly distributed, and there is no validated sampling method for detection of viruses in animal feed or ingredients. The purpose of this experiment was to evaluate the sensitivity of ingredient sampling methods for detection of porcine epidemic diarrhoea virus (PEDV). No animals were used in this experiment, so approval from an animal ethics committee was not necessary. Thirteen kg soybean meal was used in a 2 × 2 factorial plus a control, with 2 doses of PEDV (Low: 103 TCID50/g versus High: 105 TCID50/g) and two sample types (individual probes versus composite sample). Soybean meal was confirmed PEDV negative, then loaded into individual, 1‐kg polyethylene tote bags with PEDV introduced after loading the first 100 g. There were six replicates per PEDV dose plus a control. Ten individual probes or one composite sample per bag were created and analysed for PEDV via qRT‐PCR. The interaction, dose and sample type were significant for both PEDV presence and quantity. No control samples had detectable PEDV. At the low dose, no PEDV RNA was detected in individual probes or composite samples, but was confirmed in 100% (32.4 Ct) of the inoculant samples. This is likely due to loss of sensitivity during the analysis process, which has been previously reported to cause a loss up to 10 Ct when detecting PEDV in feed or ingredients. At the high dose, only 37% (37.7 Ct) of the probes had detectable PEDV RNA. Composite samples were more sensitive (p < .05), with PEDV RNA detected in 100% of samples (35.7 Ct). In summary, sampling bulk ingredients for PEDV should include compositing at least 10 individual samples. Future research is needed to identify alternative methods that have a similar sensitivity, but require less time and effort to collect such a sample.

Global pork production has largely adopted on-farm biosecurity to minimize vectors of disease transmission and protect swine health. Feed and ingredients were not originally thought to be substantial vectors, but recent incidents have demonstrated their ability to harbor disease. The objective of this paper is to review the potential role of swine feed as a disease vector and describe biosecurity measures that have been evaluated as a way of maintaining swine health. Recent research has demonstrated that viruses such as porcine epidemic diarrhea virus and African Swine Fever Virus can survive conditions of transboundary shipment in soybean meal, lysine, and complete feed, and contaminated feed can cause animal illness. Recent research has focused on potential methods of preventing feed-based pathogens from infecting pigs, including prevention of entry to the feed system, mitigation by thermal processing, or decontamination by chemical additives. Strategies have been designed to understand the spread of pathogens throughout the feed manufacturing environment, including potential batch-to-batch carryover, thus reducing transmission risk. In summary, the focus on feed biosecurity in recent years is warranted, but additional research is needed to further understand the risk and identify cost-effective approaches to maintain feed biosecurity as a way of protecting swine health.

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Six farms were examined, each from a different sector of Scottish agriculture. Surveys were carried out to identify both diffuse pollution risks and options for habitat conservation and enhancement. Financial data were also gathered to determine the current sources of farm income, both from sale of produce and from grants. Whole farm plans were produced aimed at bringing about reductions in diffuse pollution to water, soil and air and also habitat improvements. The assembled information was used to devise a possible agri-environment grant scheme to aid the implementation of the whole farm plans.

Senecavirus A (SVA) is an emerging virus impacting the U.S. swine herd. Environmental swabbing can help better detect the probability of feed contamination than product testing, but the detection of SVA by swabs has not yet been validated. Therefore, the objective of this experiment was to validate standardized swabbing techniques for detection of SVA. A secondary objective was to determine if a freeze/thaw cycle impacted detectable RNA. This experiment was a 3×4×2 factorial, with 3 forms (inoculum, feed, or swab), 4 doses (0, 10^3, 10^5, or 10^7 TCID50/mL SVA), and 2 storage methods (analyzed initially vs. after a freeze/thaw cycle). One mL SVA was added to 16 g of swine feed. One g reserved, and remaining 15 g spread over a 10 cm×10 cm stainless steel coupon and incubated for 15 minutes. Feed was removed, but residual feed dust remained. Next, surfaces were swabbed, swabs vortexed, and supernatants collected. Samples were split, with one set analyzed initially, and another frozen at -20°C for 7 days, then thawed and analyzed. Results are expressed as threshold cycle (Ct) from qRT-PCR analysis. There were 4 replicates per treatment. There was a sample type×SVA dose interaction (P < 0.0001; Table 1). Feed samples were approximately 8 Ct higher than the inoculum, and swab samples were approximately 4 Ct higher than feed. As expected, SVA level impacted (P < 0.0001) detectable SVA RNA. Finally, a freeze/thaw cycle did not impact (P = 0.846) detectable SVA RNA compared to samples that were analyzed immediately. In summary, this research validated that an environmental swab can be used to detect SVA in feed, however with approximately 4 Ct lower than analyzing feed samples directly. Furthermore, the limit of detection of SVA in environmental swabs appears to be near 10^3 TCID50/mL. Finally, samples can be frozen prior to analysis without impacting detectable SVA RNA.