Pelleting and particle size reduction of corn increase net energy and digestibility of fiber, protein, and fat in corn-soybean meal diets fed to group-housed pigs

BACKGROUND

Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy. Pelleting may also reduce particle size of grain, but it is not known if there are interactions between particle size reduction and pelleting. The objective of this experiment was to test the hypothesis that particle size reduction and pelleting, separately or in combination, increase N balance, apparent total tract digestibility (ATTD) of fiber and fat, and net energy (NE) in corn-soybean meal diets fed to group-housed pigs.

METHODS

Six corn-soybean meal-based diets were used in a 3 × 2 factorial design with 3 particle sizes of corn (i.e., 700, 500, or 300 μm) and 2 diet forms (i.e., meal or pelleted). Pigs were allowed ad libitum access to feed and water. Twenty-four castrated male pigs (initial weight: 29.52 kg; standard diviation: 1.40) were allotted to the 6 diets using a 6 × 6 Latin square design with 6 calorimeter chambers (i.e., 4 pigs/chamber) and 6 periods. Oxygen consumption and CO2 and CH4 productions were measured during fed and fasting states and fecal and urine samples were collected.

RESULTS

Regardless of particle size of corn, the ATTD of gross energy (GE), N, and acid-hydrolyzed ether extract (AEE), and the concentration of NE were greater (P < 0.05) in pelleted diets than in meal diets. Regardless of diet form, the ATTD of GE, N, and AEE, and the concentration of NE were increased (linear; P < 0.05) by reducing the particle size of corn, but the increase was greater in meal diets than in pelleted diets (interaction; P < 0.05).

CONCLUSIONS

Both pelleting and reduction of corn particle size increased nutrient digestibility and NE, but increases were greater in meal diets than in pelleted diets.

Almond hulls and shells as an alternative fiber source in limit-fed growing beef cattle diets

Almond hulls and shells are a by-product of almond production that can be incorporated as a feed ingredient in beef cattle diets. Three experiments were conducted to determine the effects of hammermill screen size on almond hull and shell bulk density and inclusion of ground or non-ground almond hulls and shells in limit-fed growing diets on growth performance, diet digestibility, and ruminal fermentation characteristics of beef cattle. In experiment 1, almond hulls and shells were ground with a laboratory-scale hammermill using no screen, a 11.1-mm screen, a 19.1-mm screen, or a 25.4-mm screen. Each screen-size treatment was ground at three separate time points (n= 3 replications/treatment). Grinding almond hulls and shells with no screen increased bulk density by 111% and minimized proportions of fine particles; therefore, almond hulls and shells ground using no screen were included as a treatment in the following experiments. In experiment 2, 364 steers (initial body weight [BW]: 257± 20.7 kg) were blocked by truckload (n = 4), stratified by BW, and assigned to pen within block. Pens were randomly assigned to 1 of 4 experimental diets (n= 10 pens/treatment). The control diet (CON) contained (DM basis) 39.5% dry-rolled corn, 7.5% supplement, 40% wet-corn gluten feed, and 13% prairie hay. Non-ground (13AH) or ground (13GAH) almond hulls and shells replaced prairie hay and were fed at 13% of diet DM or non-ground almond hulls and shells were fed at 26% of diet DM and replaced 13% prairie hay and 13% dry-rolled corn (26AH). Diets were limit-fed at 2.2% of BW daily (DM basis) for 56 d. Overall average daily gains (ADG) were greater (P ≤ 0.05) for CON, 13AH, and 13GAH compared with 26AH. In addition, ADG from days 14 to 56 were greater (P= 0.03) for 13GAH and tended to be greater (P = 0.09) for 13AH compared with CON. Experiment 3 was a 4 × 4 replicated Latin square in which 8 ruminally cannulated heifers (initial BW = 378 ± 44.0 kg) were fed diets from experiment 2. Apparent dry matter digestibility did not differ (P = 0.21) among treatments. Total ruminal volatile fatty acid concentrations were greater (P ≤ 0.03) for 13GAH and 13AH compared with 26AH and tended (P = 0.06) to be greater for 13GAH compared with CON. Overall, almond hulls and shells can be utilized as an alternative to prairie hay in limit-fed growing diets without negatively influencing rates of gain or diet digestibility.

Evaluation of Truck Cab Decontamination Procedures following Inoculation with Porcine Epidemic Diarrhea Virus and Porcine Reproductive and Respiratory Syndrome Virus

This experiment aimed to evaluate commercially available disinfectants and their application methods against porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV) on truck cab surfaces. Plastic, fabric, and rubber surfaces inoculated with PEDV or PRRSV were placed in a full-scale truck cab and then treated with one of eight randomly assigned disinfectant treatments. After application, surfaces were environmentally sampled with cotton gauze and tested for PEDV and PRRSV using qPCR duplex analysis. There was a disinfectant × surface interaction (p < 0.0001), indicating a detectable amount of PEDV or PRRSV RNA was impacted by disinfectant treatment and surface material. For rubber surfaces, 10% bleach application had lower detectable amounts of RNA compared to all other treatments (p < 0.05) except Intervention via misting fumigation, which was intermediate. In both fabric and plastic surfaces, there was no evidence (p > 0.05) of a difference in detectable RNA between disinfectant treatments. For disinfectant treatments, fabric surfaces with no chemical treatment had less detectable viral RNA compared to the corresponding plastic and rubber (p < 0.05). Intervention applied via pump sprayer to fabric surfaces had less detectable viral RNA than plastic (p < 0.05). Furthermore, 10% bleach applied via pump sprayer to fabric and rubber surfaces had less detectable viral RNA than plastic (p < 0.05). Also, a 10 h downtime, with no chemical application or gaseous fumigation for 10 h, applied to fabric surfaces had less detectable viral RNA than other surfaces (p < 0.05). Sixteen treatments were evaluated via swine bioassay, but all samples failed to produce infectivity. In summary, commercially available disinfectants successfully reduced detectable viral RNA on surfaces but did not eliminate viral genetic material, highlighting the importance of bioexclusion of pathogens of interest.

Effect of the pelleting process on diet formulations with varying levels of crystalline amino acids and reducing sugars on digestibility in growing pigs

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.

Isolation of porcine reproductive and respiratory syndrome virus from feed ingredients and complete feed, with subsequent RT-qPCR analysis

We used virus isolation (VI) to determine tissue culture infectivity and reverse-transcription quantitative PCR (RT-qPCR) to determine the stability of porcine reproductive and respiratory syndrome virus 2 (PRRSV) strain P129 in solvent-extracted soybean meal (SBM), dried distillers grains with solubles (DDGS), complete swine feed (FEED), or medium (DMEM) at 4°C, 23°C, or 37°C for up to 3 d. Samples of each treatment were taken at regular intervals and processed. Supernatant was titrated and used to inoculate confluent MARC-145 cells to determine infectivity. RNA was extracted from each supernatant sample and tested by RT-qPCR to determine any change in detectable virus RNA across matrix type, temperature, and time. An interaction (p = 0.028) was observed for matrix × temperature × hour for live virus detected by VI. At 4°C, the concentration of infectious virus was greatest in DMEM, intermediate in SBM, and lowest in DDGS and FEED. DMEM also had the greatest concentration of infectious PRRSV at 23°C over time; a higher infectious virus concentration was maintained in SBM for longer than in DDGS or FEED. At 37°C, a greater concentration of infectious virus was sustained in DMEM than in the feedstuffs, with concentrations decreasing until 48 h post-inoculation. Only matrix type influenced the quantity of viral RNA detected by RT-qPCR (p = 0.032). More viral RNA was detected in the virus control than in DDGS; SBM and FEED were intermediate. By VI, we found that infectious virus could be harbored in SBM, DDGS, and FEED for a short time.

Summary of methodology used in enterotoxigenic Escherichia coli (ETEC) challenge experiments in weanling pigs and quantitative assessment of observed variability

Postweaning diarrhea in pigs is often caused by the F4 or F18 strains of enterotoxigenic Escherichia coli (ETEC). To evaluate interventions for ETEC, experimental infection via a challenge model is critical. Others have reviewed ETEC challenge studies, but there is a lack of explanation for the variability in responses observed. Our objective was to quantitatively summarize the responses and variability among ETEC challenge studies and develop a tool for sample size calculation. The most widely evaluated response criteria across ETEC challenge studies consist of growth performance, fecal consistency, immunoglobulins, pro-inflammatory cytokines, and small intestinal morphology. However, there is variation in the responses seen following ETEC infection as well as the variability within each response criteria. Contributing factors include the type of ETEC studied, dose and timing of inoculation, and the number of replications. Generally, a reduction in average daily gain and average daily feed intake are seen following ETEC challenge as well as a rapid increase in diarrhea. The magnitude of response in growth performance varies, and methodologies used to characterize fecal consistency are not standardized. Likewise, fecal bacterial shedding is a common indicator of ETEC infection, but the responses seen across the literature are not consistent due to differences in bacterial enumeration procedures. Emphasis should also be placed on the piglet's immune response to ETEC, which is commonly assessed by quantifying levels of immunoglobulins and pro-inflammatory cytokines. Again, there is variability in these responses across published work due to differences in the timing of sample collection, dose of ETEC pigs are challenged with, and laboratory practices. Small intestinal morphology is drastically altered following infection with ETEC and appears to be a less variable response criterion to evaluate. For each of these outcome variables, we have provided quantitative estimates of the responses seen across the literature as well as the variability within them. While there is a large degree of variability across ETEC challenge experiments, we have provided a quantitative summary of these studies and a Microsoft Excel-based tool was created to calculate sample sizes for future studies that can aid researchers in designing future work.

Investigation of the environmental presence of Salmonella spp. in finishing pigs at commercial swine farms in Kansas (United States)

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 125-136 kilograms. Samples were collected and transported to the laboratory for processing following USDA-FSIS guidelines. Susceptibility and resistance profiles were also studied. Fifty-three % (100/186) of samples were culture positive for Enterobacteriaceae, and 14% (14/100) were confirmed Salmonella positive by PCR with 3 of 5 farms having no PCR-positive samples. S. Braenderup was the most common serovar identified in environmental samples, while S. 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.

Diet production and utilization of corn fermented protein compared to traditional yeast in healthy adult cats

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.

Evaluating a dry vs. wet disinfection in boot baths on detection of porcine epidemic diarrhea virus and porcine reproductive and respiratory virus RNA

Maintaining biosecurity between swine barns is challenging, and boot baths are an easily implementable option some utilize to limit pathogen spread. However, there are concerns regarding their efficacy, especially when comparing wet or dry disinfectants. The objective of this study was to evaluate the efficacy of boot baths in reducing the quantity of detectable porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV) genetic material using wet or dry disinfectants. Treatments included 1) control, 2) dry chlorine powder (Traffic C.O.P., PSP, LLC, Rainsville, AL), and 3) wet quaternary ammonium/glutaraldehyde liquid (1:256 Synergize, Neogen, Lexington, KY). Prior to disinfection, rubber boots were inoculated with 1 mL of a co-inoculants of PRRSV (1×10 5 TCID50/mL) and PEDV (1×10 5 TCID50/mL) and dried for 15 minutes. After the drying period, a researcher placed the boot on the right foot and stepped directly on a stainless steel coupon (control). Alternatively, the researcher stepped first into a boot bath containing either the wet or dry sanitizer, stood for 3 s, and then stepped onto a steel coupon. After one minute, an environmental swab was then collected and processed from each boot and steel coupon. The procedure was replicated 12 times per disinfectant treatment. Samples were analyzed using a duplex qPCR at the Kansas State Veterinary Diagnostic Laboratory. Cycle threshold values were analyzed using SAS GLIMMIX v 9.4 (SAS, Inc., Cary, NC). There was no evidence of a disinfectant × surface × virus interaction (P &gt; 0.10). An interaction between disinfectant × surface impacted (P &lt; 0.05) the quantity of detectable viral RNA. As expected, the quantity of the viruses on the coupon were greatest in the control, indicating that a contaminated boot has the ability to transfer viruses from a contaminated surface to a clean surface. Comparatively, the dry disinfectant treatment resulted in no detectable viral RNA on either the boot or subsequent coupon. The wet disinfectant treatment had statistically similar (P &gt; 0.05) viral contamination to the control on the boot, but less viral contamination compared to the control on the metal coupon. In this experiment, a boot bath with dry powder was the most efficacious in reducing the detectable viral RNA on both boots and subsequent surfaces.

Detection and investigation of atypical porcine pestivirus in a swine production system

A commercial farrow-to-finish farm was suspicious of atypical porcine pestivirus (APPV) after observing clinical signs of congenital tremors (CT) and splay leg (SL) of newborn pigs. If introduced onto the farrow-to-finish, the two potential routes of introduction could be through replacement gilts or incoming semen doses. Therefore, this study aimed to determine the prevalence of clinical APPV within the sampled population, identify the route of APPV introduction to this system, and determine prevalence of detectable APPV RNA within a population of gilt multiplication farm offspring through an isolation nursery and finisher barn. Farrowing records were analyzed for the presence of CT or SL and corresponding parity of the dam. Overall, prevalence of clinically affected litters within batch farrowing groups ranged from 0 to 31%. Phylogenetic analysis was conducted on a serum sample from a gilt at the isolation nursery, semen dose for the farrow-to-finish farm, and serum of a CT piglet. Results indicated that the virus circulating in clinically affected piglets was most similar to an incoming semen dose (98.9% nucleotide identity). Blood samples were collected at four time points and revealed APPV clinical prevalence was 37.5–77.5% during the nursery phase and 0–26% during the finisher phase. Oral fluids were also collected during the finisher phase and APPV clinical prevalence was 100% for all sampling time points. In summary, introduction of APPV into naïve herds is associated with increased clinical CT and SL cases and is detectable in asymptomatic pigs during the nursery and finisher production phases. This study found that potential screening tests for APPV could include oral fluids or qRT-PCR analysis of semen doses especially when trying to identify prevalence levels on naïve farm.

Impact of storage conditions and premix type on water-soluble vitamin stability

Mitigation options to reduce the risk of foreign animal disease entry into the United States may lead to degradation of some vitamins. The objective of Exp. 1 was to determine the impact of 0, 30, 60, or 90 d storage time on water-soluble vitamin (riboflavin, niacin, pantothenic acid, and cobalamin) stability when vitamin premix (VP) and vitamin trace mineral premix (VTM) were blended with 1% inclusion of MCFA (1:1:1 blend of C6:C8:C10) or mineral oil (MO) with different environmental conditions. Samples stored at room temperature (approximately 22˚C) or in an environmentally-controlled chamber set at 40˚C and 75% humidity, high temperature high humidity (HTHH). The sample bags were pulled out at d 0, 30, 60 and 90 for room temperature (RT) condition and HTHH condition. Therefore, treatments were analyzed as a 2 × 2 × 2 × 3 factorial, with 2 premix types (vitamin premix vs VTM), 2 oil types (mineral oil, MO vs MCFA), 2 storage conditions (room temperature, RT vs high temperature and high humidity, HTHH) and 3 time points (d 30, 60, and 90).The objective of Exp. 2 was to determine the effect of heat pulse treatment and MCFA addition on water-soluble vitamin (riboflavin, niacin, pantothenic acid and cobalamin) stability with two premix types. A sample from each treatment was heated at 60°C and 20% humidity. Therefore, treatments were analyzed as a 2 × 2 factorial, with 2 premix types (VP vs VTM) and 2 oil types (MO vs MCFA). For Exp. 1, the following effects were significant for riboflavin: main effect of premix type (P &lt; 0.0001), storage condition (P = 0.015) and storage time (P &lt; 0.0001); for pantothenic acid: premix type × storage time × storage condition (P = 0.003) and premix type × oil type (P &lt; 0.0001) interactions; and for cobalamin: premix type × storage condition (P &lt; 0.0001) and storage time × storage condition (P &lt; 0.0001) interactions and main effect of oil type (P = 0.018). The results of Exp. 2 demonstrated that there was an interaction between oil type and premix type for only pantothenic acid (P = 0.021). The oil type did not affect the stability of riboflavin, niacin, or cobalamin and pantothenic acid stability was not different within similar premixes. The only difference in water-soluble vitamin stability between VP and VTM was for pantothenic acid (P &lt; 0.001). The results of this experiment demonstrated that the stability of water soluble vitamins are dependent on the vitamin of interest and the conditions at which it is stored.

Developing a gateway program for importing non-animal origin ingredients from regions with African swine fever virus

The US Department of Agriculture (USDA) categorizes the risk of African swine fever virus (ASFV) entry into the United States through non-animal origin feed ingredients as 'negligible to moderate, with high uncertainty'. Both Canada and Australia have implemented policies that are suggested to reduce the risk of ASFV entry through feed ingredients, but the United States has not because of scientific limitations that have been addressed by recent publications. As regulators and industry consider a potential pathway forward, the objective of this manuscript is to describe a process to determine if a voluntary or regulatory import policy is warranted by the United States. Initially, the volume and types of non-animal origin feed ingredients imported from countries with ASFV were quantified and assigned a level of risk (high risk: unprocessed grains and oilseeds, moderate risk: soybean co-products (meals, oil, and oilcake), and low risk: amino acids, vitamins, and other synthetically produced products from countries that have ASFV). In 2020, moderate- and high-risk ingredients from ASFV-positive countries represented 3.1% of all ingredients imported into the United States. Policies from Canada and Australia were evaluated for practicality of implementation by US government officials. Industry representatives from both countries consistently stated their policies would not be feasible in the United States due to the differences in cost and complexity of the swine and feed industries. Overall, unprocessed, or high-risk, ingredients from ASFV-positive countries represent a low percentage of imported ingredients into the United States; however, cautionary procedures may still be warranted given industry demand.

A Longitudinal Investigation of the Effects of Age, Dietary Fiber Type and Level and Injectable Antimicrobials on the Fecal Microbiome and Antimicrobial Resistance of Finisher Pigs

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 (d 98-177 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 d 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 d 1 and 3 along with pen-mate untreated controls on d 1. Fecal samples were subjected to 16S rRNA amplicon-based microbiome analysis and culture methods to quantify the abundance of total and 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 versus 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 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. Further, diets and antimicrobial treatment had minimal impact on the overall counts of AMR coliforms and enterococci populations in feces.

53 Evaluating the Efficacy of Boot Baths with Wet and Dry Disinfectants for Porcine Epidemic Diarrhea Virus and Porcine Reproductive and Respiratory Syndrome Virus

Maintaining biosecurity between barns is challenging. Boot baths, either wet or dry, can be implemented to limit pathogen spread. The objective was to evaluate the efficacy of boot baths using wet or dry disinfectants for porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV). Treatments included 1) control, 2) wet disinfectant (Synergize, Neogen, Lexington, KY), and 3) dry disinfectant (Traffic C.O.P., PSP, LLC, Rainsville, AL). Prior to disinfection, 0.5 mL of both PRRSV (~1×105 TCID50/mL) and PEDV (~1×105 TCID50/mL) was placed onto a new boot with a layer of autoclaved corn dust and allowed to dry for 15 minutes. After the mixture dried, the boot was put on and stepped into its respective boot bath. After 3 seconds, the boot was lifted out of the bath and stepped onto a stainless-steel coupon to simulate walking through a facility. Both boot and coupon were allowed to dry for 1 minute before swabs were taken from both surfaces. Samples were analyzed in a duplex PCR at the Kansas State Veterinary Diagnostic Laboratory. Cycle threshold values were analyzed using SAS GLIMMIX v 9.4 (SAS, Inc., Cary, NC). There was no evidence of a treatment×surface×virus interaction (P &gt; 0.10). The interaction between treatment×surface impacted (P &lt; 0.05) the quantity of detectable RNA. The control had greater concentration of virus on the coupon than the boot. The reverse was true for boots treated with wet disinfectant, where the boot had a greater concentration of virus than the coupon. Treatment×virus also impacted detectable RNA (P &lt; 0.05), where wet and control boots had greater quantities of PEDV RNA than PRRSV. There was no detectable virus when dry disinfectant was used. For this trial, dry disinfectant was the most efficacious in reducing the viral RNA on both boots and subsequent surfaces; however, further research in commercial settings is warranted.

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PSVIII-1 Evaluating the Efficacy of Acidifiers Used in Nursery Diets in Reducing Bacterial Loads in Both Non-Inoculated and Inoculated Complete Feed

Acidifiers are used in nursery pig diets to reduce the incidence of diarrhea, improve growth performance, and act as a feed preservative. The objective was to evaluate whether acidifiers were able to reduce bacteria presence in non-inoculated feed and reduce bacteria growth in feed inoculated with Escherichia coli and Enterococcus faecium. Each culture media was arranged in a 2×5 factorial with 2 phases and 5 diets. The diets were 1) control – no antibiotics, 2) ZnO (Phase 1: 3,000 ppm Zn and Phase 2: 2,000 ppm Zn), 3) formic acid at 0.7% of the diet (Amasil-NA; BASF Corp. Florham, NJ), 4) glycerol monolaurate – GML at 0.18% of the diet (Natural Biologics, Newfield, NY), and 5) FORMI-3G at 1.0% of the diet (Addcon Gmbh, Bitterfeld-Wolfen, Germany). Non-inoculated feed was plated onto Aerobic Count, E. coli/Coliform, and Enterobacteriaceae petrifilm (3M, St. Paul, MN). Inoculated feed was initially contaminated with E. coli or E. faecium and allowed to incubate prior to plating on MacConkey. There was no difference (P &gt; 0.05) in quantity of bacteria for the diets inoculated with E. coli. There was no difference (P &gt; 0.05) between the diets inoculated with E. faecium for phase 1; however, the formic acid diet had reduced (P &lt; 0.05) quantities of bacteria compared with control, ZnO, and GML diets. The control and ZnO phase 1 non-inoculated diets had reduced (P &lt; 0.05) quantities of aerobic bacteria, coliforms, and Enterobacteriaceae compared with GML. In phase 2 only the control had reduced (P &lt; 0.05) quantities of Enterobacteriaceae compared with the ZnO and formic acid diets. Formic acid was able to reduce E. faecium quantities in phase 2, while the control and ZnO had decreased overall bacterial loads in phase 1.

164 Awardee Talk: Influence of Ingredient Quality and Diet Formulation on Amino Acid Digestibility and Growth Performance of Poultry and Swine

Ingredient varieties and heat processing can influence nutrient utilization for monogastric species. Objective 1 determined the influence of SBM quality on AA digestibility and growth performance of broilers. Treatments consisted of 1 of 4 soybean sources varying in CP content and processed into SBM; 2 sources from a similar region were either commercially or experimentally solvent extracted. Broilers fed commercially processed SBM had improved (P &lt; 0.05) AA digestibility compared with experimentally processed SBM from a similar region. Increasing CP content increased AA digestibility. Broiler d18 BW improved (P&lt;0.05) in broilers fed conventionally processed SBM compared with experimentally processed SBM. Feed intake improved (P &lt; 0.05) when broilers were fed conventionally processed SBM compared with experimentally processed SBM with experimentally processed SBM from a similar source intermediate. Objective 2 determined the effects of diet formulation and pelleting on AA digestibility and growth performance of swine. Diets were fed in mash or pelleted form and formulated with low or high crystalline AA and low or high RS (reducing sugars; DDGS and bakery meal). There was no feed form × crystalline AA × RS interaction observed for SID of AA. For main effects of feed form, the SID of total AA, CP, and indispensable AA increased (P &lt; 0.042) in pigs fed pelleted diets compared with mash diets. Average daily feed intake decreased (P = 0.001) and G:F and caloric efficiency improved (P = 0.001) in pigs fed pelleted diets compared with mash diets. Pigs fed diets with high crystalline AA had increased (P &lt; 0.024) ADFI compared with those fed diets with low crystalline AA. Pigs fed high RS diets had decreased (P &lt;0.041) ADG, ADFI, G:F, and caloric efficiency compared with those fed low RS. Results concluded that pelleting diets with increased crystalline AA or RS did not lead to a reduction in AA digestibility or affect the pigs’ response to pelleting.

61 Persistence and Distribution of African Swine Fever Virus in Feed and Feed Mill Environment Over Time After Manufacture of Experimentally Inoculated Feed and Subsequent Manufactured Batches of Feed

To reduce the risk of feed-based pathogens causing disease, some feed manufacturers quarantine high-risk ingredients before their inclusion in feed. Data exists that confirms this practice is effective, but there is no information about swine pathogen survival in mill environments. This objective of the study was to determine survival of African swine fever virus (ASFV) in swine feed and mill surfaces. A pilot-scale feed mill manufactured a batch of ASFV-free feed (Batch 1), followed by a batch inoculated with ASFV (5.6×104 TCID50/gram; Batch 2). Then 4 subsequent ASFV-free batches were manufactured (Batch 3-6). After each batch,10 feed samples were aseptically collected in a double ‘X’ pattern. During feed manufacturing, 24 steel coupons were placed on the floor of the manufacturing area and feed dust settled on them during the milling process and overnight. Feed samples and steel coupons were stored at room temperature. Three of each were randomly selected and analyzed for ASFV DNA on d 1, 3, 7, 14, 28, 60, 90, and 180. The interaction of batch and day impacted (P = 0.023) the number of genomic copies detected per gram of feed. There were no differences of genomic copies/g in early batches; but the quantity of detectable ASFV decreased with increasing storage time after collection. In Batches 4-6, the greatest quantity of ASFV was detected on d 1, but the lowest quantity was detected on d 7, 60, and 28 or 180 for Batches 5, 6, and 7, respectively. There was no evidence (P = 0.433) of ASFV degradation on environmental coupons over the 180-d storage period. This study found that quarantine time can help reduce, but not eliminate ASFV in feed over time. However, ASFV survives on feed manufacturing surfaces for at least 180 d. Additional research is necessary to evaluate the viability of detected virus to cause illness.

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PSV-5 Effects of Benzoic Acid and an Essential Oils Blend on Detection of Swine Viruses in Inoculated Swine Feed and Premix

Feed has been shown to harbor viable viruses over an extended period. This study investigated the use of benzoic acid (BA) and an essential oils blend (EO) to mitigate the presence of porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome virus (PRRSV), and Senecavirus A (SVA) in a complete diet (Exp. 1) and a vitamin premix (Exp. 2). Experiment 1 consisted of a control with no additive, 0.5% BA, 0.5% BA and 200 ppm EO, 0.3% BA and 120 ppm EO, and 0.25% BA and 100 ppm EO. Feed samples were inoculated with PEDV, PRRSV, and SVA. For Exp. 2, the control contained no additive, and treatment had 2.68% EO included to mitigate PEDV. Inoculated feed or premix was stored at room temperature with sampling points at 2, 5, and 15 d post-inoculation (dpi). Samples were analyzed using triplex qRT-PCR to detect changes in RNA quantities for all viruses. Detectible PRRSV in the feed demonstrated a quadratic decrease over time (P = 0.038). A significant treatment × day interaction was observed in the feed for both PEDV (P = 0.008) and SVA (P &lt; 0.001). The 0.5% BA treatment had greater (P &lt; 0.05) amounts of detectible PEDV on d 2 and 5 and decreased detectible PEDV on d 15 compared with control. The 0.5% BA treated feed demonstrated decreased (P &lt; 0.05) detectable SVA at 2 dpi but greater detectible SVA at 15 dpi compared with control. Both PEDV and SVA demonstrated viral degradation over time. The use of the EO in the vitamin premix had no evidence of main or interactive effects. In conclusion, 0.5% BA decreased PEDV at 15 dpi, but BA and EO mitigation in this model did not provide consistent evidence for increased viral degradation. However, time decreased detectability of all three viruses.

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Inoculation of Weaned Pigs by Feed, Water, and Airborne Transmission of Salmonella enterica Serotype 4,[5],12:i:

ABSTRACT

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.

HIGHLIGHTS

Using caloric efficiency to estimate the net energy value of expelled, extruded soybean meal relative to dehulled, solvent-extracted soybean meal and its effects on growth performance of nursery pigs

This study aimed to estimate the net energy (NE) value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SSBM) and determine its effects on growth performance of late nursery pigs. A total of 297 pigs (DNA 241 × 600) were weaned (BW 5.10 kg) and placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed a common diet for 21 d. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SSBM in the diet (0%, 25%, 50%, 75%, and 100%). All diets were fed for 28 d and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded requirements for amino acids, calcium, and phosphorus. The SSBM diet was formulated to 2,421 kcal/kg and NE was not balanced between diets. Analyzed values for CP, EE, CF, and total lysine for the SSBM were 47.28%, 0.47%, 3.80%, and 3.00%, whereas the MSBM contained 47.41%, 6.88%, 5.32%, and 2.99%, respectively. The MSBM had increased values for KOH solubility and trypsin inhibitor (83.62% and 7,026 TIU/g) compared to the SSBM (73.05% and 3,011 TIU/g), whereas urease activity was similar between the two (0.03 and 0.02 Δ pH, respectively). Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P < 0.001) G:F and caloric efficiency on an NE basis. Using caloric efficiency to estimate NE of the MSBM relative to SSBM, MSBM was estimated to have a value of 2,566 kcal/kg. In conclusion, MSBM contains approximately 123% of the energy of SSBM, which improved feed efficiency when fed to nursery pigs.

Assessment of soy-based imports into the United States and associated foreign animal disease status

Soy-based products are known to pose a viable risk to U.S. swine herds because of their ability to harbour and transmit virus. This publication aimed to evaluate soy imports into the United States as a whole and from foreign animal disease positive (FAD-positive) countries to determine which products are being imported in the highest quantities and observe potential trends in imports from FAD-positive countries. Import data were accessed through the United States International Trade Commission website (USITC DataWeb) and summarized using R (version 4.0.2, R core team, Vienna, Austria). Twenty-one different Harmonized Tariff Schedule (HTS) codes were queried to determine quantities (metric tonnes, MT) and breakdown of different soy product types being imported into the United States from 2015 to 2020. A total of 78 different countries exported soy products to the United States in 2019 and 2020 with top contributors being Canada (546,467 and 481,497 MT, respectively), India (397,858 and 430,621 MT, respectively) and Argentina (122,116 and 79,471 MT, respectively). Soy oilcake (582,273 MT) was imported in the largest quantities, followed by organic soybeans (270,194 MT) and soy oil (134,436 MT) for 2020. Of the 78 countries, 46 had cases of FAD reported through the World Organization for Animal Health (OIE) World Animal Health Information Database (WAHIS). Top exporters of soy products to the United States from FAD-positive countries in 2019 and 2020 were India (397,858 and 430,621 MT, respectively), Argentina (122,116 MT in 2019) and Ukraine (40,293 and 56,392 MT, respectively). The risk of FAD introduction to the United States through soy imports can fluctuate based on where FAD outbreaks are occurring, shipping methods and end usage of products. A system to monitor these factors could help make future decisions about trade and risk of FAD introduction to U.S. swine herds.

Sampling and detection of African swine fever virus within a feed manufacturing and swine production system

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.

Effect of cleaning corn on mycotoxin concentration and nursery pig growth performance

Mycotoxins are naturally produced hazards that result from molds grown on cereal grains and other commodities. These molds may produce carcinogenic mycotoxins, which can be harmful to humans and animals. Removing broken kernels has been demonstrated to reduce mycotoxin concentration, but with high variability. Therefore, two experiments were conducted to quantify the magnitude of natural mycotoxin concentration that may be reduced by cleaning corn. Two loads of corn that were naturally contaminated with mycotoxins were procured. Corn for Experiment 1 was contaminated with aflatoxin (1,074 parts per billion; ppb), fumonisin (8.3 parts per million; ppm), and ochratoxin A (206 ppb), while corn for Experiment 2 was contaminated with only fumonisin (5.5 ppm). Corn was cleaned by mechanical sieving. For each experiment, corn was divided into twenty 150 kg runs. Runs were randomly assigned to 1 of 4 experimental treatments: 1) no screen 2) 12.7 mm screen, 3) 4.8 mm screen, and 4) 12.7 + 4.8-mm screen. The corn cleaner was sanitized between runs. Three 5 kg corn samples were collected from each run, and analyzed for mycotoxin concentration. In Experiment 1, cleaning reduced (P < 0.05) aflatoxin and fumonisin concentration by an average of 26% and 45%, respectively, compared to the original uncleaned corn level, but did not impact (P > 0.10) ochratoxin A. The resultant screenings had nearly four times the aflatoxin (4,224 ppb) and 7.5 times the fumonisin concentration (60.4 ppm) as the uncleaned corn. In Experiment 2, cleaning reduced (P < 0.05) fumonisin concentration by 32%. The resultant screenings had 19.6 times the fumonisin concentration (65.4 ppm) as the uncleaned corn. To determine the effect that cleaning corn may have on nursery pig growth performance, 360 nursery pigs were used in Experiment 3 to evaluate the impact of cleaning or pelleting on growth performance. Treatments were arranged in a 2 × 3 factorial with corn type (uncleaned vs. cleaned) and feed form (mash vs. pelleted from either mill A or B). Neither cleaning corn nor pellet mill type affected (P > 0.19) nursery pig growth performance. Pelleting improved (P < 0.0001) gain to feed ratio (G:F) by 7.6% compared to mash diets. These data suggest that cleaning is an effective method to legally reduce aflatoxin and fumonisin concentration, but does not impact animal growth performance. Screenings should be used cautiously when feeding to animals.

Effects of conditioning temperature and pellet mill die speed on pellet quality and relative stabilities of phytase and xylanase

The objective of this experiment was to determine the effect of conditioning temperature and die speed on pellet quality and enzyme stability of phytase and xylanase. Treatments were initially arranged as a 2 × 3 factorial of conditioning temperature (74 and 85 °C) and die speed (127, 190, and 254 rpm); however, when conditioning at 85 °C, it was not possible to pellet at 127 rpm. Thus, data were analyzed in two different segments using the GLIMMIX procedure of SAS. First, linear and quadratic contrasts were utilized to test the response to increasing die speed at 74 °C. Second, the data was analyzed as a 2 × 2 factorial of conditioning temperature (74 and 85 °C) and die speed (190 and 254 rpm). Treatments were arranged in a completely randomized design and replicated three times. Diets were conditioned for approximately 30 s and pelleted with a 4.8-mm-diameter × 44.5-mm-effective length die at a rate of 4.5 MT/h. Pellet durability index (PDI) was determined using the tumble box and Holmen NHP 100 methods. Samples of the unconditioned mash (M), conditioned mash (CM), and pellets (P) were collected and analyzed for phytase and xylanase concentration. Relative enzyme stabilities were expressed as CM:M, P:CM, and P:M. Stabilities expressed as P:M were used an indication of enzyme stability through the entire pelleting process. Diets conditioned at 74 °C showed no evidence of difference in phytase or xylanase P:M stability when decreasing die speed from 254 to 127 rpm. However, when conditioning diets at 74 °C, decreasing die speed increased (linear, P < 0.001) PDI. There was no conditioning temperature × die speed interaction for overall xylanase P:M stability or PDI. However, there was a conditioning temperature × die speed interaction (P < 0.01) for phytase P:M stability. When conditioning diets at 85 °C, increasing die speed decreased phytase P:M stability. However, when conditioning at 74 °C, increasing die speed did not influence phytase P:M stability. For main effects of conditioning temperature, increasing temperature improved (P < 0.001) PDI with no evidence of difference for xylanase P:M stability. For the main effects of die speed (254 vs. 190 rpm), decreasing die speed decreased (P < 0.001) the P:M xylanase stability, but there was no evidence of difference for PDI. The results of this trial indicate that die speed should be taken into consideration when evaluating enzyme stability of both phytase and xylanase as pellet mill models may be operating at different speeds. Additionally, increasing conditioning temperature will improve PDI but may result in decreased phytase stability.

Using environmental sampling to evaluate the effectiveness of decontamination methods to reduce detection of porcine epidemic diarrhea virus RNA on feed manufacturing surfaces

Porcine epidemic diarrhea virus (PEDV) is a possible biological hazard in feed mills. If the virus enters a feed mill, it becomes widely distributed and is difficult to decontaminate from both feed contact and non-feed contact surfaces. The objective of this study was to evaluate a variety of liquid and dry decontamination treatments that could be used to reduce the amount of PEDV found on feed manufacturing surfaces. This experiment was designed as a 5 × 10 factorial with five different feed manufacturing surfaces and 10 decontamination treatments with three replicates of each combination. Surfaces included stainless steel, solid polyethylene, woven polypropylene tote bag, rubber, and sealed concrete coupons. One mL (1×10⁵ TCID₅₀/mL) of stock PEDV was applied to each surface and allowed to dry completely for 60 min. Next, for decontamination requiring surface application, the application was performed and allowed 15 min contact time. The quantity of PEDV RNA was determined using quantitative reverse transcription PCR. A decontamination treatment × surface interaction was observed (P < 0.0001), indicating the efficacy of treatment is dependent upon the surface in which it is applied. Within the cement surfaces, the sodium hypochlorite resulted in the greatest (P < 0.05) cycle threshold (Ct) value, followed by formaldehyde which had a greater (P < 0.05) Ct value compared to remaining treatments. Within polyethylene, rubber, and stainless steel surfaces, the formaldehyde treated surfaces had the greatest Ct values (P < 0.05), followed by the sodium hypochlorite treatment, with other treatments all having lower Ct values (P < 0.05). For the woven polyethylene surfaces, the formaldehyde and sodium hypochlorite treatments had greater Ct values compared to all other treatments (P < 0.05). Additional research is necessary to identify the role of decontamination treatment on PEDV infectivity and develop methods for decontamination of feed manufacturing facilities.

The influence of particle size of Enogen Feed corn and conventional yellow dent corn on nursery and finishing pig performance, carcass characteristics and stomach morphology

Enogen Feed corn is a variety developed by Syngenta Seeds (Downers Grove, IL) that has been genetically modified to contain an α-amylase enzyme trait (SYT-EFC). Originally, Enogen feed corn was developed for the ethanol industry due to its reduction in viscosity of the corn mash, thus eliminating the need to add a liquid form of the α-amylase enzyme. However, there is a potential application for Enogen Feed corn to be used in livestock diets due to the increase in α-amylase enzyme potential to increase starch digestibility. A more common method of increasing starch digestibility in corn is to finely grind it to reduce particle size. This increases the surface area and allows for greater interaction with digestive enzymes. We hypothesized that pigs fed Enogen feed corn potentially could achieve similar gain:feed ratio (G:F) at larger particle sizes than conventional corn because of the differences in starch digestibility. In experiment 1, a total of 360 pigs (DNA 200 × 400, Columbus, NE; initially 6.6 ± 0.1 kg BW) were used with five pigs per pen and 12 pens per treatment. Treatments were arranged in a 2 × 3 factorial with main effects of corn source (Enogen Feed corn or conventional yellow dent corn) and ground corn particle size (300, 600, or 900 µm). Overall, there was a corn source × particle size interaction (linear, P = 0.027) for G:F. There was no effect due to particle size when pigs were fed conventional yellow dent corn, but in pigs fed Enogen Feed corn, G:F increased with decreasing particle size. Neither corn source nor particle size affected (P > 0.05) overall average daily gain (ADG) or average daily feed intake (ADFI). In experiment 2, a total of 323 pigs (241 × 600; DNA, Columbus, NE; initially 50.0 ± 1.3 kg) were used with nine pigs per pen and six pens per treatment. Treatments were identical as experiement 1. Overall, corn source had no effect on finishing pig ADG, ADFI or G:F. For corn particle size, ADG and G:F increased (linear, P < 0.014) and ADFI decreased (P = 0.043) as particle size decreased. For stomach morphology, there was a tendency for a corn source × particle size interaction (P = 0.055) for keratinization score with keratinization increasing linearly (P = 0.001) as particle size of the corn decreased for yellow dent corn with no change in keratinization score as particle size decreased for Enogen Feed corn. In summary, reducing corn particle size improved G:F with no major differences observed between corn sources for overall pig performance.

Effect of mixing and feed batch sequencing on the prevalence and distribution of African swine fever virus in swine feed

It is critical to have methods that can detect and mitigate the risk of African swine fever virus (ASFV) in potentially contaminated feed or ingredients bound for the United States. The purpose of this work was to evaluate feed batch sequencing as a mitigation technique for ASFV contamination in a feed mill, and to determine if a feed sampling method could identify ASFV following experimental inoculation. Batches of feed were manufactured in a BSL-3Ag room at Kansas State University's Biosafety Research Institute in Manhattan, Kansas. First, the pilot feed manufacturing system mixed, conveyed, and discharged an ASFV-free diet. Next, a diet was manufactured using the same equipment, but contained feed inoculated with ASFV for final concentration of 5.6 × 10⁴ TCID₅₀ /g. Then, four subsequent ASFV-free batches of feed were manufactured. After discharging each batch into a collection container, 10 samples were collected in a double 'X' pattern. Samples were analysed using a qPCR assay for ASFV p72 gene then the cycle threshold (Ct) and Log₁₀ genomic copy number (CN)/g of feed were determined. The qPCR Ct values (p < .0001) and the Log₁₀ genomic CN/g (p < .0001) content of feed samples were impacted based on the batch of feed. Feed samples obtained after manufacturing the ASFV-contaminated diet contained the greatest amounts of ASFV p72 DNA across all criteria (p < .05). Quantity of ASFV p72 DNA decreased sequentially as additional batches of feed were manufactured, but was still detectable after batch sequence 4. This subsampling method was able to identify ASFV genetic material in feed samples using p72 qPCR. In summary, sequencing batches of feed decreases concentration of ASFV contamination in feed, but does not eliminate it. Bulk ingredients can be accurately evaluated for ASFV contamination by collecting 10 subsamples using the sampling method described herein. Future research is needed to evaluate if different mitigation techniques can reduce ASFV feed contamination.

Faecal concentrations of ceftiofur metabolites in finisher pigs administered intramuscularly with ceftiofur

The objective of this study was to determine the effects of dietary fibre level and source on faecal ceftiofur metabolites concentrations after intramuscular administration of therapeutic ceftiofur hydrochloride in finisher pigs. Pens of finisher pigs (n = 36), with an equal number of barrows and gilts, were randomly assigned to 1 of 3 dietary treatment groups: basal diet composed of corn grain and soy bean meal with no supplement and formulated to contain 8.7% neutral detergent fibre (NDF), supplemented with 20% distillers dried grains with solubles (a byproduct of the ethanol production from corn grain) formulated to contain 13.6% NDF, primarily insoluble fibre or supplemented with 14.5% sugar beet pulp formulated to contain 13.6% NDF. Faecal samples were collected 6–8 hr after ceftiofur injection from treated and untreated pen‐mate pigs on days 1 and 3 of the 3‐day treatment regimen. Faecal concentrations of ceftiofur metabolites, including the major metabolite, desfuroylceftiofur, were analysed by reverse‐phase high pressure liquid chromatography with ultraviolet detection. Overall, the faecal concentrations of ceftiofur metabolites did not differ significantly between the dietary treatments. The mean concentrations of metabolites tended to be lower (p = .1) on day 3 compared to day 1 of the 3‐day treatment regimen. Faecal concentrations of metabolites were not affected by the gender of the finisher pigs. The concentrations of ceftiofur metabolites in the faeces are likely reflective of the microbial activity in the hindgut. Our data suggest that the fibre level and source used in the study did not affect the faecal concentrations of ceftiofur metabolites.

44 Effects of Decreasing Corn Particle Size on Metabolizable Energy and Proportions of Fecal Volatile Fatty Acids in Gestating Sows

The objective of the first experiment was to determine the effects of corn particle size on the diet apparent total tract digestibility (ATTD) of protein (CP), digestible energy (DE), metabolizable energy (ME) and N-corrected ME (AMEn) in addition to estimating the ME of corn in gestating sows. A total of 27 sows, during the second phase of gestation, were fed a common diet manufactured with corn ground to one of 3 target particle sizes (dgw): 400, 800, or 1200 µm. Titanium dioxide (0.25%) was included in the diet as an indigestible marker for digestibility calculations. Sows were fed experimental diets for 7 days to allow for diet adaptation before a 2-day collection period of urine and fecal samples. Reducing dgw of corn from 1,200 to 400 µm increased (linear, P &lt; 0.01) ATTD CP and GE, DE, ME, AMEn and calculated ME of corn. The objective of the second experiment was to determine the effects of corn particle size on the total concentration and molar proportions of volatile fatty acids (VFA) in the feces of gestating sows. A total of 27 sows were fed treatments similar to Exp. 1 from day 61 to 82 of gestation. On day-82 and 83 of gestation, 2 fecal grab samples were collected for VFA analyses. Sows fed diets with decreasing corn dgw had increased (quadratic, P = 0.021) fecal acetic acid proportions, and decreased propionic (quadratic, P = 0.019) and valeric acid (P = 0.005). In conclusion, for every 100 µm decrease in corn dgw from 1,200 to 400 µm, corn ME value increased by 28.6 kcal/kg. Additionally, decreasing corn particle size led to an increase in the proportion of acetic acid and a decrease in propionic and valeric acid in fecal samples of gestating sows.

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PSVI-4 Efficacy of Medium Chain Fatty Acids and Fatty Acid-based Feed Additives as a Mitigation Strategy Against Porcine Epidemic Diarrhea Virus and Porcine Reproductive and Respiratory Syndrome Virus

Recent research has demonstrated that swine viruses can be transmitted via feed. Chemical feed additives have been suggested for the mitigation of these viruses in complete feed. Therefore, the objective of this study was to evaluate the efficacy of a commercially available formaldehyde-based feed additive, medium chain fatty acid blend (MCFA), and commercially available fatty acid-based products for mitigation of porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV) in a feed matrix. Treatments consisted of: 1) non-treated positive control, 2) 0.33% commercial formaldehyde-based product (Sal Curb; Kemin Industries, Inc.; Des Moines, IA), 3) 0.5% MCFA blend (1:1:1 ratio of C6:0, C8:0, and C10:0, Sigma Aldrich, St. Louis, MO), 4) 0.25%, 5) 0.5%, or 6) 1% of commercial dry mono and diglyceride-based product (Furst Strike; Furst-McNess Company, Freeport, IL), 7) 0.25%, 8) 0.5%, or 9) 1% of commercial dry mono and diglyceride-based product (Furst Protect; Furst-McNess Company, Freeport, IL), 10) 0.25%, 11) 0.5%, or 12) 1% dry mono and diglyceride-based experimental product (Furst-McNess Company, Freeport, IL) with 3 replications/treatment. Treatments were applied to complete swine feed before inoculation with 106 TCID50/g of feed with PEDV or PRRSV. Post inoculation feed was held at ambient temperature for 24 h before being analyzed via qRT-PCR. The analyzed values represent the cycle threshold. Formaldehyde and MCFA decreased (P &lt; 0.05) the detectable RNA of PEDV and PRRSV compared to all other treatments. Furst Strike, Furst Protect, and the experimental product did not significantly impact detectability of PEDV or PRRSV RNA. In conclusion, MCFA and formaldehyde treatments are effective at reducing detection of RNA from PEDV and PRRSV in feed.

149 Evaluation of Hammermill Tip Speed, Air Assist, and Screen Hole Diameter on Ground Corn Characteristics

This study was performed to evaluate hammermill tip speed, assistive airflow and screen hole diameter on hammermill throughput and characteristics of ground corn. Corn was ground using two Andritz hammermills (Model: 4330–6, Andritz Feed & Biofuel, Muncy,PA) measuring 1-m in diameter each equipped with 72 hammers and 300 HP motors. Treatments were arranged in a 3 × 3 × 3 factorial design with 3 tip speeds (3,774, 4,975, and 6,176 m/min), 3 screen hole diameters (2.3, 3.9 and 6.3 mm), and 3 air flow rates (1,062, 1,416, and 1,770 fan RPM). Corn was ground on 3 separate days to create 3 replications and treatments were randomized within day. Samples were collected and analyzed for moisture, particle size, and flowability characteristics. Data were analyzed using the GLIMMIX procedure of SAS 9.4 with grinding run serving as the experimental unit and day serving as the block. There was a 3-way interaction for standard deviation (Sgw), (linear screen hole diameter × linear hammer tip speed × linear air flow, P = 0.029). There was a screen hole diameter × hammer tip speed interaction (P &lt; 0.001) for geometric mean particle size dgw (P &lt; 0.001) and composite flow index (CFI) (P &lt; 0.001). When tip speed increased from 3,774 to 6,176 m/min the rate of decrease in dgw was greater as screen hole diameter increased from 2.3 to 6.3 mm resulting in a 67, 111, and 254 µm decrease in dgw for corn ground using the 2.3, 3.9, and 6.3 mm screen hole diameter, respectively. For CFI, increasing tip speed decreased the CFI of ground corn when ground using the 3.9 and 6.3 mm screen. However, when grinding corn using the 2.3 mm screen, there was no evidence of difference in CFI when increasing tip speed. In conclusion, the air flow rate did not influence dgw of corn but hammer tip speed and screen size were altered and achieved a range of dgw from 304 to 617 µm.

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140 Influence of Enogen Feed Corn and Conventional Yellow Dent Corn in Pelleted or Meal-based Diets on Finishing Pig Performance and Carcass Characteristics

Previous research has indicated that starch gelatinization during the pelleting process is greater for Enogen® Feed corn compared to conventional yellow dent corn. Increasing starch gelatinization in the pellet increases the starch digestibility in the pig, which potentially leads to increased growth rate. Therefore, the objective of this study was to determine the effects of feeding Enogen Feed corn in meal or pellet form on finishing pig growth performance and carcass characteristics. A total of 288 pigs (53.0 ± 0.5 kg) were used with 8 pigs/pen and 9 pens/treatment in a 72-d study. Treatments were arranged in a 2×2 factorial with main effects of corn source (Enogen Feed corn or conventional yellow dent corn) and diet form (meal or pellet). Main effects of corn source and diet form as well as their interactions were tested. Pelleting parameters were established with a target conditioner temperature of 82.2°C and corn moisture of 13 to 14%. When pelleting the diets, the conditioning temperature for conventional yellow dent corn averaged 68.4°C and Enogen Feed corn averaged 67.7°C. The hot pellet temperature for conventional yellow dent corn averaged 75.1°C and 75.8°C for Enogen feed corn. For overall performance (d 0 to 72), no interactions between corn source and diet form were observed (P &gt; 0.05). There was a tendency (P &lt; 0.10) for slightly improved average daily gain (ADG) and gain:feed ratio (G:F) for pigs fed conventional yellow dent corn compared to those fed Enogen Feed corn. Pigs fed pelleted diets had increased (P &lt; 0.001) ADG, G:F, and hot carcass weight compared to pigs fed meal diets. In summary, feeding pelleted diets to finishing pigs increased ADG and G:F compared to those fed meal-based diets. There were no major differences observed between corn sources or interactions between corn source and diet form on growth performance.

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31 Using Caloric Efficiency to Estimate the Energy Value of Expelled, Extruded Soybean Meal Relative to Dehulled, Solvent-extracted Soybean Meal and Its Effects on Growth Performance of Nursery Pigs

This study aimed to estimate the net energy value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SBM) and determine its effects on growth performance of late nursery pigs. Analyzed values for CP, EE, CF, and lysine for the SBM were 47.28%, 0.47%, 3.80%, and 3.00% while the MSBM contained 47.41%, 6.88%, 5.32%, 2.99% respectively. A total of 297 pigs (DNA 200 x 400) were placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed common diets for 21 days. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SBM in the diet (0, 25, 50, 75, 100%). All diets were fed for 28 days and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded NRC (2012) recommendations for lysine:amino acids, calcium, and phosphorus. The SBM diet was formulated to 2421 kcal/kg and net energy (NE) was not balanced between diets. Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P &lt; 0.001) G:F and caloric efficiency on an NE basis. In conclusion, using caloric efficiency to estimate NE of the MSBM relative to SBM, MSBM was estimated to have a value of 123% of SBM NE or 2566 kcal/kg. This increase in NE resulted in improved feed efficiency of nursery pigs.

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PSIII-15 Effect of the Pelleting Process on Diet Formulations with Varying Levels of Crystalline AA and Reducing Sugars on Nursery Pig Growth Performance

A total of 360 pigs (DNA 200×400; initially 11.3 kg) were used in an 18-d study to determine the effect of pelleting diets with or without increased concentrations of free amino acids (AA) and reducing sugars (RS) on pig growth performance. There were 9 replications/treatment and 5 pigs/pen. Treatments were arranged in a 2×2×2 factorial with main effects of diet form (mash vs. pellet), crystalline AA (low vs. high), and RS (low vs. high) provided by dried distillers grain with solubles and bakery meal included at 20% and 15%, respectively. Diets were pelleted to achieve a conditioning temperature of 86.7°C using a 22.4 kW pellet mill equipped with a 4.7 x 34.9-mm die. Data were analyzed as a CRD using the GLIMMIX procedure of SAS. There were no 3-way interactions observed. For the main effect of feed form, ADFI decreased (P=0.001) and G:F and caloric efficiency improved (P=0.001) in pigs fed pelleted diets compared to mash diets. For the main effect of crystalline AA, pigs fed diets with high crystalline AA had increased (P&lt; 0.024) ADFI compared to those fed diets with low crystalline AA. For the main effect of RS, pigs fed high RS diets had decreased (P&lt; 0.041) ADG, ADFI, G:F, and caloric efficiency compared to those fed low RS. In conclusion, there was no evidence of interactions between treatments, indicating that increasing amounts of crystalline AA and RS did not influence the response to pelleted diets. Pigs fed the high RS diets had reduced feed intake which resulted in reduced gain and improved feed and caloric efficiency.

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199 Effect of the Pelleting Process on Diet Formulations with Varying Levels of Crystalline Amino Acids and Reducing Sugars on Digestibility in Growing Pigs

The objective of this study was to determine effects of pelleting on the standardized ileal digestibility (SID) of amino acids (AA) in diets with or without increased concentrations of free AA and reducing sugars (RS). Eight individually housed, ileal cannulated barrows (initially 69.2 kg) were allotted to a replicated 8×8 Latin square with 8 diets and eight 7-d periods with ileal digesta collected on d 6 and 7. Treatments were arranged in a 2×2×2 factorial with main effects of diet form (mash vs. pellet), crystalline AA (low vs. high), or reducing sugars (low vs. high) provided by dried distillers 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 completely randomized Latin square using the GLIMMIX procedure of SAS. A feed form×RS interaction (P &lt; 0.026) for SID of tryptophan was observed. Feeding pelleted low RS diets improved SID of tryptophan compared with mash high and low RS diets, and pelleted high RS diets. For main effects of feed form, the SID of total AA, CP, and indispensable AA increased (P &lt; 0.042) in pigs fed pelleted diets compared with mash diets. For 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 main effects of RS diets, pigs fed high RS diets had decreased (P &lt; 0.05) SID of total AA, CP and indispensable AA. In conclusion, pelleting diets with increased crystalline AA or RS did not affect the improvement in AA digestibility from pelleting. Pelleting diets improved AA digestibility. 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.

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PSVI-7 Evaluation of Feed Mitigant Efficacy for Control of Porcine Epidemic Diarrhea Virus and Porcine Reproductive and Respiratory Syndrome Virus When Inoculated Either Alone or Together

Research has demonstrated that swine feed can be a fomite for viral transmission and certain feed additives can effectively reduce viral contamination. However, additional information is needed to evaluate the efficacy of additives when feed is inoculated with more than one virus. The objective of this study was to evaluate the efficacy of two feed additives for mitigation of porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV) when inoculated individually or together. Feed additives included: 1) no treatment, 2) 0.33% commercial formaldehyde-based product (Sal Curb, Kemin Industries, Des Moines, IA), and 3) 0.50% medium chain fatty acids blend (MCFA; 1:1:1 ratio of C6:C8:C10, Sigma Aldrich, St. Louis, MO). Samples were inoculated with PEDV and PRRSV alone or together at an inoculation concentration of 106 TCID50/g for all viruses. Once inoculated, feed was stored at ambient temperature for 24-h before analyzed via qRT-PCR. For samples inoculated with PEDV or PRRSV alone, a qRT-PCR assay was used which was designed to detect PEDV or PRRSV nucleic acid. For co-inoculated samples, an assay was designed to independently detect both PEDV and PRRSV within a single reaction. For PEDV alone, there was marginally significant evidence that feed additives resulted in differences in cycle threshold (Ct) value (P = 0.052), but no evidence was observed for pairwise differences. For PRRSV alone, formaldehyde increased Ct compared to the untreated control and MCFA treatment (P &lt; 0.05). For co-infection of PRRSV and PEDV, MCFA and formaldehyde increased Ct (P &lt; 0.05) in comparison to non-treated feed. In summary, formaldehyde increased Ct values in feed when contaminated with PRRSV while both mitigants increased Ct value in feed when co-inoculated with PRRSV and PEDV.

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Influence of particle size of Enogen Feed corn and conventional yellow dent corn on lactating sow performance

Enogen Feed corn is a variety developed by Syngenta Seeds (Downers Grove, IL) that has been genetically modified to contain an -amylase enzyme trait (SYT-EFC). Originally, Enogen feed corn was developed for the ethanol industry due to its properties for reducing the viscosity of its corn mash. There is potential application for Enogen Feed corn to be used in livestock diets due to the potential for the increase in - amylase enzyme to increase the starch digestibility. Because of this, it may be possible to increase the particle size of ground Enogen Feed corn and maintain the same starch digestibility as finely ground conventional yellow dent corn. Therefore, our hypothesis was that an interaction between corn source and particle size would exist such that the performance of sows fed fine ground conventional yellow dent corn would be similar to sows fed coarse ground Enogen Feed corn. A total of 107 sows (Line 241; DNA, Columbus, NE) across four batch farrowing groups were used to evaluate sow and litter performance. Treatments were arranged in a 2 2 factorial with main effects of corn source (Enogen Feed corn or conventional yellow dent corn) and ground corn particle size (600 or 900 m). From farrowing to weaning, there was a tendency for a corn source particle size interaction (P = 0.065) in sow body weight (BW) change. Sows fed 900 m Enogen Feed corn had decreased BW loss compared to sows fed other treatments, which were similar in weight loss. For sow average daily feed intake from farrowing to weaning, there was a corn source particle size interaction (P = 0.048) with sows fed 900 m conventional yellow dent corn having lower feed intake than the sows fed 600 m conventional yellow dent corn, whereas sows fed 900 m Enogen Feed corn had greater feed intake compared to the sows fed 600 m Enogen Feed corn. There was a tendency for a particle size main effect (P < 0.10) for litter average daily gain (ADG) and total litter gain, with sows fed corn ground to 600 m having increased litter ADG and total litter gain compared to sows fed corn ground to 900 m. In summary, there were few differences in sow or litter characteristics among those fed Enogen Feed corn or conventional yellow dent corn. Reducing particle size of both corn sources tended to increase litter ADG and weaning weights.

PSVII-12 Acceptability of Milne blueberry juice and blueberry puree in horse feed

The objective of this study was to evaluate the impact of liquid blueberry juice (BJ65) or blueberry puree (BP30) used as a binding agent on pellet durability and palatability of a typical equine concentrate when included at 4% of the pellet. Molasses was used as a control. Production data, pellet durability and moisture content were evaluated in 1 replicate for each treatment. Because moisture content of condition mashes were 17.59% and 18.11% for BJ65 and BP30 treatments, respectively, greater inclusion of blueberry product would likely cause roller slippage and complicate the pelleting process due to increased liquid (Fahrenholz, 2012). Pellet durability met industry standards for all treatments. Pellets were fed in a 3 x 3 Latin square design to 9 two-year-old horses to determine the effect of blueberry products on acceptability. All animals were allowed 10 minutes to consume 1.36 kg at 0700 h and 1700 h each day for 3 d. Consumption time and amount consumed were recorded to calculate intake, intake rate, and intake ratio (IR). No horse consumed all pellets within the allotted time, and thus, there were no differences between intake rate and intake. Period tended to impact intake (P = 0.0909), with horses consuming less during period 1 than period 3 (P = 0.0317), but period had no effect (P = 0.2881) on IR. Treatment influenced intake (P &lt; 0.0001), with decreased intake of BP30 compared to control and BJ65 (P ≤ 0.0001). Intake ratio was greater (P = 0.0075) for BJ65 than BP30 with IR of 0.5069 and 0.4227, respectively. Consumption of BJ65 was no different than control. Fahrenholz, A. 2012. Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability. Doctoral thesis. Kansas State University, Manhattan, KS.

PSI-24 The Effect of Formic Acid and Lignosulfonate on Pellet Quality

The objective of this study was to determine the effect of formic acid and lignosulfonate (LignoTech USA) on pellet quality. The 5 treatments consisted of a control, or the control with 2 levels of formic acid (0.36% and 0.60%), or the control with formic acid with lignosulfonate (0.24% and 0.40%). Diets were steam conditioned (245 mm×1397 mm Wenger twin shaft pre-conditioner, Model 150) for approximately 30 sec and pelleted on a 1-ton 30-horsepower pellet mill (1012-2 HD Master Model, California Pellet Mill) with a 4.8 mm×31.8 mm pellet die (L:D 6.7). The production rate was set at 900 kg/h. Treatments were pelleted at 3 separate time points to provide 3 replicates per treatment. Samples were collected directly after discharging from the pellet mill and cooled in an experimental counterflow cooler. Samples were analyzed for pellet durability index using the Holmen NHP 100 (TekPro Ltd, Norfolk, UK) and via both standard and modified tumble box methods. Pellet hardness was determined by evaluating the peak amount of force applied before the first signs of fracture. Pellets were crushed perpendicular to their longitudinal axis using a texture analyzer (Model TA-XT2, Stable Micro Systems). Voltage and Amperage data was collected via Supco DVCV Logger (Supco, New Jersey, US). Data were analyzed using the MIXED procedure in SAS 9.4, with pelleting run as the experimental unit. Increasing formic acid in the diet decreased (linear, P &lt; 0.0001) pH. No evidence for differences were observed for pellet mill energy consumption, pellet durability regardless of testing method or pellet hardness when adding formic acid or lignosulfonate to the diet. In conclusion, pellet quality was not influenced by formic acid or lignosulfonate.

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50 Pelleting and Starch Characteristics of Diets Containing Enogen® Feed Corn

This experiment determined the effects of die thickness and conditioning temperature on pelleting and starch characteristics in diets containing conventional or Enogen® feed corn (Syngenta Seeds, LLC). Treatments were arranged as a 2 × 2 × 3 factorial of corn type (conventional [CON] and Enogen® feed corn [EFC]), die thickness (5.6 and 8.0 length:diameter [L:D]), and conditioning temperature (74, 79, and 85°C). Diets were steam conditioned and pelleted (CPM Model 1012-2) with a 4 × 22.2 mm or 4 × 31.8 mm pellet die. Conditioner retention time was set at 30 s and production rate was set at 15 kg/min. All treatments were replicated on 3 separate days. Data were analyzed using the GLIMMIX procedure in SAS (v. 9.4, SAS Institute Inc., Cary, NC). Increasing die L:D improved PDI (P=0.01) and increased (P=0.02) energy consumption. Increasing conditioning temperature from 74 to 85°C increased (linear, P&lt; 0.03) PDI (84.2, 84.9, and 88.2%, respectively) and tended to decrease energy consumption (quadratic, P=0.07). There was a corn × conditioning temperature interaction (P=0.01) for gelatinized starch in conditioned mash. Enogen® feed corn diets steam conditioned at 85°C had the greatest quantity of gelatinized starch. Cooked starch of conditioned mash was greater (P&lt; 0.01) for EFC diets compared to CON diets and increased (linear, P&lt; 0.01) with increasing conditioning temperature. Starch gelatinization was greater (P&lt; 0.01) in pelleted EFC diets (13.4%) compared to CON diets (11.7%) and was increased (linear, P=0.05) by increasing conditioning temperature from 74 to 85°C (12.0, 12.1, and 13.4%, respectively). Pelleted diets containing EFC had increased (P&lt; 0.01) cooked starch compared to CON diets. In conclusion, increasing die L:D and increasing conditioning temperature improved PDI. Starch gelatinization was increased when diets were pelleted at the highest conditioning temperature of 85°C, and EFC diets resulted in greater gelatinized starch.

PSIX-11 Effects of Spray-Dried Lactococcus-Based Fermentation Products on Growth Performance of Nursery Pigs

A total of 720 barrows (initially 5.9 kg; Line 200 × 400; DNA, Columbus, NE) were used in a 42-d growth trial to test the effects of spray-dried Lactococcus-based fermentation products on nursery pig performance. There were 24 replications per treatment with pen randomly allotted to 1 of 6 dietary treatments. The positive control (PC) diet included zinc oxide (ZnO; phase 1), ZnO + chlortetracycline (CTC; phase 2) while the negative control (NC) diet did not include ZnO or CTC. Treatment diets included the negative control + 1 of 4 fermentation products (C, D, E, or F) added at 5% of the diet. Phase 3 diets contained a common control diet fed to all pigs plus treatment diets with fermentation products. Data were analyzed with pen as the experimental unit and barn within group as the blocking factor using PROC-GLIMMIX in SAS. From d 0 to 20, there was an overall treatment effect (P = 0.001) where pigs fed PC had increased (P &lt; 0.05) d 20 BW, ADG, ADFI, and improved G:F compared to those fed the NC and NC + fermentation product. Overall, there was a treatment effect (P = 0.03) for pigs fed the PC having improved (P &lt; 0.05) ADG and G:F compared to the NC and NC + fermentation product. In addition, pigs fed the NC had improved (P &lt; 0.05) G:F compared to those fed additive D, E, and F. In conclusion, pigs fed the PC (zinc + CTC) diet had improved performance compared to pigs fed the NC with or without fermentation product. Adding fermentation products to the NC diet did not improve nursery pig performance.

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PSIX-9 Effects of Conditioning Temperature on Pellet Quality of Nursery Pig Diets

The objective of this experiment was to determine the effect of conditioning temperature on pellet durability index (PDI) and pellet hardness. A nursery pig diet was formulated to contain 25% spray-dried whey. Treatments consisted of three different conditioning temperatures: 54, 63, and 71°C. Diets were steam conditioned (245 mm × 1397 mm Wenger twin staff pre-conditioner, Model 150) for approximately 30 sec and pelleted using a 1-ton 30-horsepower pellet mill (1012-2 HD Master Model, California Pellet Mill) with a 4.8 mm × 31.8 mm pellet die (L:D 6.7). The production rate was set at 900 kg/h. Treatments were pelleted at 3 separate time points to provide 3 replicates per treatment. Samples were collected directly after discharging from the pellet mill and cooled in an experimental counterflow cooler. Samples were analyzed for PDI using the Holmen NHP 100 for 60 sec (TekPro Ltd, Norfolk, UK). Pellet hardness was determined by evaluating the peak amount of force applied before the first signs of fracture. Although conditioning temperature was increased in a linear fashion, a quadratic increase (P &lt; 0.002) in hot pellet temperature (HPT) was observed. The HPT were 68, 72, and 74°C for diets conditioned to 54, 63 and 71°C, respectively. Increasing conditioning temperature resulted in increased (linear, P &lt; 0.045) PDI and pellet hardness. As conditioning temperature increased from 54, to 71°C PDI increased from 87% to 92% and the force required to crush pellets increased from 13.5 to 15.9 kg. There was a tendency for a correlation (P &lt; 0.076, r = 0.618, r2 = 0.382) between pellet hardness and PDI. Overall, increasing the conditioning temperature increased pellet hardness and pellet durability.

PSI-11 Moisture Content Throughout the Pelleting Process and Subsequent Effects on Pellet Quality

This experiment was designed to evaluate the effects of steam addition to the conditioner on moisture content throughout the pelleting process and subsequent effects on pellet quality. Treatments consisted of diets pelleted with no steam and steam added to achieve conditioning temperatures of 62.8 and 87.8°C. Conditioner retention time was set at 30 sec and diets were pelleted with a 6.4×63.5 mm pellet die. Pellet samples were collected and immediately placed in an experimental counter-flow cooler for 15 min. All treatments were replicated at 3 separate time points to provide 3 replicates per treatment. Mash (M), conditioned mash (CM), hot pellets (HP), and cooled pellet (CP) samples were collected for moisture content analysis and CP for pellet durability index (PDI). Data were analyzed with pelleting run as the experimental unit and time period as the blocking factor. Moisture samples were analyzed as a 3×4 factorial of steam-conditioning and sample location. There was a steam-conditioning×sample interaction (P&lt; 0.01) for moisture. Mash samples for all treatments were similar (13.3%; 36.2°C). For the no steam treatment, there was no difference in moisture content for the M, CM, and HP; however, moisture decreased in CP, with samples having 13.4, 13.1, 12.9, and 12.0% moisture, respectively. For the 62.7°C treatment, there was an increase in moisture from M to CM, followed by a decrease in both HP and CP, with samples having 13.2, 15.3, 14.9, and 12.7% moisture, respectively. For the 87.8°C treatment, moisture increased from M to CM, and decreased in HP and CP with samples having 13.3, 17.3, 16.3, and 13.4% moisture, respectively. Increasing conditioning temperature from no steam to 87.8°C increased (P&lt; 0.01) PDI from 3.3, 59.1, to 91.1%, respectively. In conclusion, increasing feed temperature from 36.2 to 87.8°C via steam addition increased condition mash moisture content by 4.2% resulting in improved pellet quality.

305 Awardee Talk: Transferring a culture of biosecurity to the feedmill

A culture of on-farm biosecurity has been established and practiced by modern swine production systems for many years. The value of this has been repeatedly demonstrated through improved animal health and performance based on the prevention of disease introduction to the herd. With the introduction of Porcine Epidemic Diarrhea Virus (PEDV) to the US swine industry in 2013, we have learned that feed and feed ingredients can be vectors of disease transmission. Therefore, there is a heightened need to transfer our on-farm biosecurity culture to our feedmills and entire feed supply chain as a way to help prevent disease introduction into swine farms. Feedmills are designed to efficiently and effectively blend feed components into a homogenous batch, and the potential to distribute contaminated feed to multiple farms is significant. While feed and ingredients can be vectors of disease and pathogen transmission, our data continues to show that people are a major risk for pathogen transmission throughout the feed supply chain. Key biosecurity principles such as exclusion, prevention, isolation, mitigation, disinfection, and containment should be adopted and enforced for a strong feedmill biosecurity program. A written feedmill biosecurity plan should be developed and a training program that covers all employees as well as visitors and delivery drivers should be implemented. Continuous risk assessment and environmental monitoring should be utilized to identify new areas of risk and to assess the current status. Unfortunately, feedmills are nearly impossible to completely disinfect and therefore every effort should be made to prevent the introduction of pathogens into the mill. Research that we have conducted with PEDV and African Swine Fever Virus has demonstrated that adopting a culture of biosecurity at the feedmill will reduce risk of disease and pathogen exposure on farms.

PSIII-35 The effects of cold pelleting and separation of fine corn particles on growth performance of nursery pigs

A total of 320 pigs (DNA 241×600; initially 10.2 kg BW) were utilized in a 21-d experiment to determine the effects of corn fractionation and pelleting technique on nursery pig growth performance. There were 5 pigs per pen, 8 pens per treatment and 8 dietary treatments in a randomized complete block design. Treatments 1–3 contained 400 µm ground corn and were fed as either mash, pelleted using a steam conditioner plus traditional vertical ring die (steam pellet) or pelleted with hot water plus a horizontal die (cold pellet). Treatments 4–6 contained corn ground to 400 µm with fines &lt; 150 um removed and were fed as either mash, steam pellet or cold pellet. Treatments 7 and 8 contained ground corn with only fines &lt; 150 um steam or cold pelleted prior to dietary inclusion without complete diet pelleting. Overall, pigs fed mash diets had improved (P &lt; 0.05) ADG and d 21 BW compared to those fed steam pelleted diets with those fed cold pelleted diets being intermediate. There was no difference in G:F between pigs fed mash, steam pellet and cold pellet diets; however, pigs fed diets containing pelleted fines had decreased (P &lt; 0.05) G:F due to an observed increased feed wastage and sorting. There was no difference in growth performance between pigs fed diets with fines removed or not. Cold pelleting was a viable option to steam pelleting in the current experiment; however, pelleting diets reduced pig performance compared to pigs fed mash diets, which was unexpected. Further research is needed to validate the response to cold pelleting when the expected response to pelleting using steam conditioning is achieved.

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PSVIII-6 Effect of Pellet Die Thickness and Conditioning Temperature During the Pelleting Process on Phytase Stability

This experiment evaluated the effects of pellet die thickness and conditioning temperature on microbial phytase stability. Treatments were arranged as a 2 × 3 factorial of die thickness (5.6 and 8.0 length:diameter [L:D]) and conditioning temperature (74, 79, and 85°C). Phytase was added to a corn-soybean meal-based diet. The diet was steam conditioned (245 × 1397 mm Wenger twin staff pre-conditioner, Model 150) and pelleted (CPM Model 1012-2) with a 4 × 22.2 mm (5.6 L:D) or 4 × 31.8 mm (8.0 L:D) pellet die. Conditioner retention time was set at 30 s and production rate was set at 15 kg/min. All treatments were replicated over 3 days. Conditioned mash and pellet samples were collected and immediately placed in an experimental counter-flow cooler for 15 min. Samples were analyzed for phytase activity and pellet durability index (PDI). Conditioning temperature, hot pellet temperature (HPT), and production rate were recorded throughout each processing run. Data were analyzed using PROC GLIMMIX in SAS (v. 9.4), with pelleting run as the experimental unit and day as the blocking factor. There was no evidence (P &gt;0.14) for any die thickness × conditioning temperature interactions. Pelleting with the 8.0 L:D die increased (P &lt; 0.01) HPT (83.2 and 84.2°C) and PDI (81.9 and 89.7%). Increasing conditioning temperature from 74 to 85°C increased (linear, P&lt; 0.03) HPT (80.1, 83.6, and 87.5°C , respectively) and PDI (84.3, 84.9, and 88.2%, respectively) and decreased (linear, P&lt; 0.01) phytase stability from 97.1 to 35.8% in conditioned mash and from 60.8 to 25.9% in cooled pellets. There was no difference (P &gt;0.72) in stability due to die thickness. Results of this experiment demonstrated phytase stability decreased linearly as temperature rose above 74°C. Although the thicker pellet die increased HPT and PDI, the rise in HPT was not great enough to reduce phytase stability.

157 The effect of different inclusion levels of corn starch and fine ground corn with different conditioning temperatures or die thickness on pellet quality

The objective of this experiment was to determine the effect of different inclusion levels of corn starch and fine ground corn with different conditioning temperature or die thickness on pellet quality. Experiment 1, treatments were arranged in 3×2 factorial design of corn starch inclusion level (0, 5 and 10%) and die thickness (4mm×13mm and 4mm×22 mm). Experiment 2, treatments were arranged in 3×2 factorial design of fine ground corn inclusion level (0, 10 and 20) and conditioning temperature (80 and 85°C) with treatments pelleted using a 4mm×22mm die (5.6 L:D). In both experiments, treatments were pelleted using a model CL-5 CPM pellet mill (Crawfordsville, IN). The result of experiment 1 demonstrated that there was no interaction between corn starch inclusion level and die thickness on modified pellet durability index (PDI), (P=0.636). Increasing die thickness from 12.7 to 22.2 mm increased PDI from 43 to 70% (P&lt; 0.001). There was a linear decrease (P&lt; 0.001) in PDI as the corn starch inclusion level increased from 0 to 10% (64, 60, and 46%, respectively). The result of experiment 2 demonstrated that there was no interaction between fine ground corn inclusion level and conditioning temperature on PDI (P=0.541). The fine ground corn inclusion level did not impact PDI (P=0.298). Increasing conditioning temperature from 80 to 85°C increased PDI (P&lt; 0.001) from 76 to 85%, respectively (P&lt; 0.001). Based on the results, the use of pure corn starch was not an effective binding agent in the feed when the diet contains at least 60% ground corn. The ratio of small corn particles to large corn particles in the diet did not impact pellet quality when the diets were conditioned above 80°C for 35 sec and then pelleted with a 5.6 L:D die. Increasing die thickness and conditioning temperature improved pellet quality.

60 Use of environmental monitoring to inform biosecurity compliance in a swine health challenge

As endemic and foreign diseases threaten the U.S. swine herd, producers are scrutinizing on-farm biosecurity practices. Environmental monitoring may help inform biosecurity compliance. Unfortunately, the Kansas State Swine Teaching and Research Center suffered an outbreak of porcine epidemic diarrhea virus (PEDV) in March 2019. The objective of this research was to use environmental monitoring to evaluate biosecurity risk on a farm experiencing a viral outbreak. In a completely randomized design, environmental swabs were collected after barn sanitation on 14, 28, and 42-days after initial PEDV diagnosis from four zones: 1) pig contact surfaces within barns, 2) non-pig contact surfaces within barns, 3) outside barns and inside offices, and 4) transition areas. Swabs were analyzed for PEDV, rotavirus, and Enterobacteriaceae at a veterinary diagnostic laboratory. Data were analyzed using the GLIMMIX procedures of SAS, v 9.4 (Cary, NC). There was a significant time × zone interaction for PEDV (P &lt; 0.0001), where swabs from non-pig contact areas within barns on d 28 (Zone 2) had greater (P &lt; 0.05) levels of PEDV than pig-contact areas (Zone 1) on d 14, 28, or 42. No other interactions existed, and they were therefore removed from the statistical model. Time did not affect (P &gt; 0.05) any measured response criteria. No PEDV was detected (45.0 Ct) from Zone 1 due to recent sanitation, but viral presence was highest (P &lt; 0.05) in non-pig contact areas inside barns and was tracked outside of barns and through transition zones (32.9, 34.3, and 38.5 Ct for zones 2, 3, and 4, respectively). There was no detected difference (P &gt; 0.05) for rotavirus or Enterobacteriaceae in time or zone. In conclusion, producers experiencing a PEDV outbreak may successfully decontaminate pig-contact surfaces, but still have risk throughout the farm. Biosecurity practices should support preventing cross-contamination from other contaminated areas.

Pelleting and starch characteristics of diets containing different corn varieties

This experiment determined the effects of die thickness and conditioning temperature on pelleting and starch characteristics in diets containing conventional or Enogen Feed corn (Syngenta Seeds, LLC). Treatments were arranged as a 2 × 2 × 3 factorial of corn type [conventional (CON) and Enogen Feed corn [EFC]), die thickness [5.6 and 8 length:diameter (L:D)], and conditioning temperature (74, 79, and 85 °C). Diets were steam conditioned (Wenger twin staff preconditioner, Model 150) and pelleted (CPM, Model 1012-2) with a 4- × 22.2-mm (L:D 5.6) or 4- × 31.8-mm (L:D 8) pellet die. Conditioner retention time was set at 30 s and production rate was set at 15 kg/min. All treatments were represented within three replicate days. Pellets were composited and analyzed for gelatinized starch and pellet durability index (PDI). Conditioning temperature, hot pellet temperature, production rate, and pellet mill energy consumption were recorded throughout each processing run. Data were analyzed using the GLIMMIX procedure in SAS (v. 9.4, SAS Institute Inc., Cary, NC) with pelleting run as the experimental unit and day as the blocking factor. Pelleting with a larger die L:D improved PDI (P = 0.01) and increased (P = 0.02) pellet mill energy consumption. Increasing conditioning temperature from 74 to 85 °C increased (linear, P < 0.03) PDI and tended to decrease energy consumption (quadratic, P = 0.07). There was a corn × conditioning temperature interaction (P = 0.01) for gelatinized starch in conditioned mash. Enogen Feed corn diets steam conditioned at 85 °C had the greatest quantity of gelatinized starch. Cooked starch in conditioned mash and pellets was greater (P < 0.01) for EFC diets compared to CON diets and increased (linear, P < 0.01) with increasing conditioning temperature in conditioned mash. Similarly, starch gelatinization was greater (P < 0.01) in pelleted EFC diets compared to CON diets and was increased (linear, P = 0.05) by increasing conditioning temperature from 74 to 85 °C. In conclusion, increasing die L:D and increasing conditioning temperature improved PDI. Starch gelatinization was increased when diets were pelleted at the highest conditioning temperature of 85 °C, and EFC diets resulted in greater starch gelatinization than conventional corn.