It is critical to understand the role feed manufacturing may have regarding potential African swine fever virus (ASFV) transmission, especially given the evidence that feed and/or ingredients may be ...potential vectors. The objective of the study was to evaluate the distribution of ASFV in a feed mill following manufacture of contaminated feed. To accomplish this, a pilot-scale feed mill consisting of a mixer, bucket elevator, and spouting was constructed in a BSL-3Ag facility. First, a batch of ASFV-free feed was manufactured, followed by a batch of feed that had an ASFV-contaminated ingredient added to feed, which was then mixed and discharged from the equipment. Subsequently, four additional ASFV-free batches of feed were manufactured using the same equipment. Environmental swabs from 18 locations within the BSL-3Ag room were collected after each batch of feed was discharged. The locations of the swabs were categorized into four zones: 1) feed contact surface, 2) non-feed contact surface < 1 meter away from feed, 3) non-feed contact surface > 1 meter from feed, and 4) transient surfaces. Environmental swabs were analyzed using a qPCR specific for the ASFV p72 gene and reported as genomic copy number (CN)/mL of environmental swab processing buffer. Genomic copies were transformed with a log10 function for statistical analysis. There was no evidence of a zone × batch interaction for log10 genomic CN/mL (P = 0.625) or cycle threshold (Ct) value (P = 0.608). Sampling zone impacted the log10 p72 genomic CN/mL (P < 0.0001) and Ct values (P < 0.0001), with a greater amount of viral genome detected on transient surfaces compared to other surfaces (P < 0.05). This study illustrates that once ASFV enters the feed mill environment it becomes widespread and movement of people can significantly contribute to the spread of ASFV in a feed mill environment.
Abstract
The inclusion of yeast in pet food can provide health benefits and increase palatability. Corn fermented protein is a co-product from ethanol production which contains approximately 20% to ...25% yeast. The objective of this study was to determine the effects of the yeast in CFP on diet production and utilization when fed to healthy adult cats. The four experimental diets included a control with 15% soybean meal (CON) and diets containing either 3.5% brewer’s dried yeast (BDY), 2.5% brewer’s dried yeast plus 17.5% distillers dried grains with solubles (BDY+DDGS), or 17.5% corn fermented protein (CFP). All treatments except CON were formulated to contain 3.5% yeast. Experimental diets were fed to adult cats (n = 11) in an incomplete 4 × 4 replicated Latin square design. Cats were adapted to diet for 9 d followed by a 5-d total fecal collection. Titanium dioxide (0.4%) was added to all diets as an external marker to estimate digestibility. Data were analyzed using a mixed model in SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and cat and period as random effects. Preconditioner discharge temperature was greater (P < 0.05) for CON and BDY (average, 96 °C) compared to BDY + DDGS and CFP (average, 91 °C). Extruder screw speed, die temperature, kibble toughness, and kibble hardness were greatest (P < 0.05) for CFP. The bulk density of BDY + DDGS at 392 g/L was greater (P < 0.05) than BDY and CFP (average, 342 g/L). The sectional expansion index of kibble for CFP was greater (P < 0.05) than BDY + DDGS and smaller (P < 0.05) than CON but similar to BDY. Fecal output was greatest (P < 0.05) for cats fed BDY + DDGS. Nutrient digestibility was lowest (P < 0.05) for BDY + DDGS. The concentrations of short-chain and branched-chain fatty acids in fecal samples were not altered (P > 0.05) by dietary treatment. Cats had no preference (P > 0.05) when comparing CON to BDY or BDY + DDGS. However, cats consumed significantly less CFP compared to CON. The significant differences for bulk density, fecal output, and nutrient digestibility among dietary treatments are likely due to a greater fiber effect of DDGS compared to CFP. Therefore, the yeast component in CFP may provide greater kibble expansion and nutrient utilization compared to DDGS when fed to cats.
Corn-fermented protein is a co-product from ethanol production which contains approximately 20% to 25% yeast. Based on the effects of CFP on processing parameters, kibble characteristics, stool quality, nutrient digestibly, and palatability compared to traditional yeast, CFP would be best utilized as a protein or fiber source for pet food.
Lay Summary
The inclusion of yeast in pet food can provide health benefits and increase palatability. Corn-fermented protein is a co-product from ethanol production which contains approximately 20% to 25% yeast. In this work, 11 cats were fed diets containing no yeast (CON) and either 3.5% brewer’s dried yeast (BDY), 2.5% brewer’s dried yeast plus 17.5% distillers dried grains with solubles (BDY+DDGS), or 17.5% corn fermented protein (CFP). Cats were fed each dietary treatment for 14 d with a 9-d adaptation phase followed by a 5-d total fecal collection. Processing parameters, kibble characteristics, stool quality, nutrient digestibility, and palatability were analyzed. Processing parameters needed to be adjusted for CFP to result in a similar bulk density to BDY. The CFP resulted in harder and tougher kibble compared to BDY. The total fecal output and fecal score of cats were similar for BDY and CFP. However, nutrient digestibility was lower for CFP compared to BDY, likely due to the increase in dietary fiber. Short-chain and branched-chain fatty acid concentrations in fecal samples were not altered among diets. The palatability of BDY appeared to be greater than CFP for cats. Further research is needed to evaluate the possible impact of yeast in CFP on animal health.
An experiment was conducted to compare the growth performance, gizzard and relative gizzard weight (RGW) of broilers fed a mash diet, micro-pellets, or coarse and fine crumbles with or without the ...fines removed. A total of 300 Cobb 500 one-day-old male broiler chicks were randomly distributed into 60 battery cages with 5 broilers per cage. Cages were randomly assigned to 1 of 6 dietary treatments to provide 10 replicates per treatment in a CRD. Treatments comprised of 1) mash (M); 2) micro-pellets (MP); 3) coarse-crumbles with fines (CCF); 4) coarse-crumbles with fines removed (CCNF); 5) fine-crumbles with fines (FCF); and 6) fine-crumbles with fines removed (FCNF). Overall BW, ADG, and ADFI were increased (P < 0.001), FCR improved (P < 0.001), and RGW decreased (P < 0.001) for broilers fed MP or crumbles compared to the M diet. Broilers fed MP, CCNF, and FCNF had increased (P < 0.05) BW compared to those fed CCF and FCF. Broilers fed the CCNF had improved (P < 0.05) FCR compared to those fed all other treatments. Gizzard weight (P = 0.0007) and RGW (P < 0.0001) were higher for birds fed M, FCF, and FCNF compared to other diets. The results of this study indicated that feeding MP or crumbles to broiler chicks improved feed intake, BW, and FCR but reduced RGW. Removing the fines resulted in further improvement in BW for broilers fed crumbles. Furthermore, feeding good quality crumbles yielded similar growth performance in chicks fed micro-pellets.
Salmonellosis remains a major foodborne disease threat to public health worldwide. Swine are considered a reservoir for many Salmonella serotypes affecting humans; however, not all serotypes of ...concern in food animal products cause clinical signs of infection in swine. The objective of this study was to evaluate the presence and distribution of Salmonella spp. in finishing pigs at commercial farms across Kansas (USA). Five farms were selected and sampled when pigs weighed between 125 and 136 kg. Samples were collected and transported to the laboratory for processing following USDA-FSIS guidelines. Susceptibility and resistance profiles were also studied. Fifty-three percent (100/186) of samples were culture positive for Enterobacteriaceae, and 14% (14/100) were confirmed Salmonella positive by PCR with three of five farms having no PCR-positive samples. Salmonella serotype Braenderup was the most common serovar identified in environmental samples, while Salm. Infantis, Agona, and Montevideo were identified in fecal samples. Multidrug resistance patterns were only found in Farm 3, in fecal samples and in one floor sample. The observations reported in this study highlight areas of concern, such as locations prone to fecal contamination, to be considered when cleaning and sanitizing between groups of pigs to decrease presence of Salmonella spp. in farm environments.
Salmonella enterica serotype 4,5,12:i:- (STM) has become an increasing problem for food safety and has been often detected in swine products. Weanling pigs were exposed to STM-contaminated feed, ...water, or air to determine possible STM transmission routes. A control group of pigs was included. STM was monitored daily in feces and rectal and nasal swabs. STM colonization was most prevalent in tissues from tonsil, lower intestine, and mesenteric lymph nodes. No differences in lesion severity were observed between inoculated and control pigs. Contaminated feed, water, and aerosolized particles caused infection in weaned pigs; however, no STM colonization was observed in skeletal muscle destined for human consumption. Based on the results from this study, STM contamination in pork products most likely results from cross-contamination of meat by digesta or lymph node tissue during processing.
The objective of this experiment was to determine the effects of pelleting on the standardized ileal digestibility (SID) of amino acids (AA) and crude protein (CP) in diets with or without increased ...concentrations of free AA and reducing sugars (RS). Eight individually housed, ileal cannulated barrows (initially 31.4 kg) were allotted to an 8 × 8 Latin square with eight diets and eight 7-d periods with ileal digesta collected on days 6 and 7. Treatments were arranged in a 2 × 2 × 2 factorial with the main effects of diet form (mash or pellet), crystalline AA (low or high), or RS (low or high), provided by distillers dried grains with solubles and bakery meal. Diets were pelleted to achieve a hot pellet temperature of 85 to 88 °C. Data were analyzed as a Latin square design using the GLIMMIX procedure of SAS 9.4. A feed form × RS interaction (P < 0.026) for SID of tryptophan was observed. Feeding pelleted low RS diets increased SID of tryptophan compared with mash high and low RS diets, and pelleted high RS diets. For the main effects of feed form, the SID of total AA, CP, and indispensable AA was greater (P < 0.042) in pelleted diets compared with mash diets. For the main effects of crystalline AA, pigs fed high crystalline AA had increased (P = 0.007) SID of tryptophan and decreased (P = 0.050) SID of histidine compared with those fed low crystalline AA diets. For the main effects of RS, high RS diets had decreased (P < 0.05) SID of total AA, CP, and indispensable AA compared with low RS diets. In conclusion, pelleting diets increased AA digestibility, and pelleting diets with increased crystalline AA or RS did not affect the improvement in AA digestibility from pelleting. Diets formulated with high crystalline AA had increased SID of tryptophan. Formulating diets with high RS resulted in decreased AA digestibility compared with corn-soybean meal-based diets.
Abstract
Age and diet are among the factors that influence the community composition of the fecal microbiome. Additionally, antimicrobial use can alter the composition of bacterial communities. An ...86-d study with finisher pigs aimed to evaluate age-related dynamics (day 98 to 177 of age), effects of types and levels of dietary fiber, and injectable antimicrobials on the fecal microbiome and antimicrobial resistance (AMR) was conducted. A total of 287 pigs, housed in 36 pens, with 7 to 8 pigs per pen, fed a corn grain and soybean meal-based basal diet, formulated to contain 8.7% neutral detergent fiber (NDF), were randomly assigned to one of three treatments: 1) basal diet with no supplement, 2) basal diet supplemented with 20% distillers dried grains with solubles (DDGS) formulated to contain 13.6% NDF, or 3) basal diet supplemented with 14.5% sugar beet pulp (SBP) formulated to contain 13.6% NDF. Five finisher pigs from each treatment group were selected randomly, and fecal samples were collected on days 98, 110, 144, and 177 of age. In addition, fecal samples were collected from pigs that were injected intramuscularly ceftiofur hydrochloride or penicillin G on days 1 and 3 along with pen-mate-untreated controls on day 1. Fecal samples were subjected to 16S rRNA amplicon-based microbiome analysis and culture methods to quantify the abundance of total AMR coliforms and enterococci populations. The alpha-diversity, such as species richness, increased with age, and the overall bacterial composition changed with age (P =0.001) and diet (P = 0.001). Diet-associated shifts in the specific bacterial taxa were observed. The richness, diversity, and evenness of bacterial taxa did not differ between pigs that were injected with ceftiofur vs. their untreated pen mates or by dietary treatments but differed in pigs that received penicillin G injection. Both antimicrobial treatments contributed to changes in the overall fecal bacterial composition at the genus level. Collectively, the data demonstrate that both age and the diet (control vs. DDGS-, control vs. SBP-, or DDGS- vs. SBP-based diets) were associated with the overall bacterial community composition, and the impact of age on variations in fecal microbiome composition was greater than the diet. Antibiotic treatment had minimal effect on bacterial diversity and relative abundance of taxa. Furthermore, diets and antimicrobial treatment had minimal impact on the overall counts of AMR coliforms and enterococci populations in feces.
Age, diet, and antimicrobial treatment can affect the overall hindgut microbiome with minimal impact on antimicrobial resistance in finisher pigs.
Lay Summary
Bacterial communities in the gut and the feces are strongly influenced by a number of factors, particularly the age of the animal and the diet. In addition, antibiotic administration routinely used to treat bacterial diseases can also affect the community composition. A study with finisher pigs was conducted to evaluate age-related changes, effects of types—distiller’s dried grains with solubles (DGGS) or sugar beet pulp (SBP)—and levels of dietary fiber, and injectable antibiotics on the fecal bacterial composition and antibiotic resistance in fecal bacteria. Fecal samples were collected from five pigs in each of the three dietary treatment groups, control diet with no supplement or supplemented with DDGS or SBP, on days 98, 110, 144, and 177 of age and on days 1 and 3 after the first injection of antibiotics, ceftiofur or penicillin G. Samples were analyzed to identify the bacterial community composition and prevalence of antibiotic resistance in fecal bacteria. Data generated suggested that the overall bacterial composition changed with age and diet, and age appeared to have a greater impact than diet. Antibiotics had only a modest impact on the bacterial community and had minimum impact on antibiotic resistance of fecal bacteria.
Transmission of biological hazards capable of causing disease in livestock can occur through a wide variety of direct and indirect routes. In swine production, there are a large number of possible ...routes of exposure of a pathogen into a susceptible population. African swine fever virus (ASFV) has been a significant challenge for Southeast Asia since first detected in China in 2018 and has spread through many countries within the region. In order to understand potential transmission pathways within an ASFV endemic region, a diagnostic investigation was performed to determine the level of contamination on a wide variety of surface types within a live animal production, feed manufacturing, and feed distribution system located in Vietnam. All diagnostic testing was performed locally by the production system's internal diagnostic laboratory using real‐time polymerase chain reaction (rt‐PCR) analysis. Early in the diagnostic investigation, it became clear that feed trucks were a common site of ASFV surface contamination detection. This information resulted in biosecurity‐focused actions for feed trucks arriving back at the feed mill, including decontamination of interior truck cab surfaces and washing of exterior truck surfaces with high‐pressure water prior to application of surface disinfectants. Additionally, a low number of rt‐PCR positive samples were detected within the feed production system, with the greatest number coming from transient surfaces such as high traffic areas and worker clothing. This illustrates the importance of managing employee traffic through procedures such as zoning and separation between clean–dirty areas to reduce the likelihood of pathogen transmission. In conclusion, this report illustrates the importance of routine data capture regarding efficacy of biosecurity procedures which allows for real‐time updates and improvement as biosecurity gaps are identified.
Background
While porcine biological hazards have had the potential to be transmitted through feed and feed mills for decades, the emerging threat of foreign animal disease has elevated the concern ...that these may enter or be transmitted throughout the domestic swine herd via a feed vehicle.
Objective
The goal of this review was to describe the current classification for emerging porcine biological pathogen transmission through the feed supply chain so resources can be best directed towards those of highest risk.
Methods
By assessing the pathogen severity to pigs and the probability of pathogen transmission through feed, an overall risk can be established using a hazard analysis matrix.
Results
There is negligible risk for feed‐based transmission of a transmissible spongiform encephalopathy, Trichinella spiralis, Toxoplasma gondii, Salmonella Choleraesuis, Salmonella spp. except Choleraesuis and I 4,5,12:i:‐, porcine deltacoronavirus, Senecavirus A, mammalian orthoreovirus 3, foot and mouth disease virus, classical swine fever virus or Chinese pseudorabies virus. However, the combined severity and probability of Salmonella enterica serotype I 4,5,12:i:‐, porcine epidemic diarrhoea virus and African swine fever virus warrant a moderate risk characterization for transmission through the US feed supply chain.
Conclusions
This risk can be maintained below critical status by minimizing the likelihood that a pathogen can enter the feed supply chain, such as by excluding high‐risk ingredients from facilities, extending biosecurity to mills, and considering proactive mitigation strategies. In reality, all these actions may be necessary to prevent the detrimental transmission of porcine biological hazards into the US swine herd through the feed supply chain.
While porcine biological hazards have had the potential to be transmitted through feed and feed mills for decades, the emerging threat of foreign animal disease has elevated the concern that these may enter or be transmitted throughout the domestic swine herd via a feed vehicle. By assessing the pathogen severity to pigs and the probability of pathogen transmission through feed, an overall risk can be established using a hazard analysis matrix. This risk can be maintained below critical status by minimizing the likelihood that a pathogen can enter the feed supply chain, such as by excluding high‐risk ingredients from facilities, extending biosecurity to mills and considering proactive mitigation strategies.
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