bluuebunny/crossref_metadata_2025 huggingface dataset:
84 Evaluating the effects of hind gut acidosis in sheep on rumen fermentation ex vivo
Authors: Prybylski Emma G , Linder Haley F , McCann Joshua C
Published: May 2024

The objective was to determine the effect of hindgut acidosis in sheep on rumen fermentation ex vivo. Eleven ruminally and cecally cannulated ewes [body weight (BW) = 49 ± 4 kg] were assigned to one of two treatments: a constant infusion of deionized water (CON; 26 mL/kg BW per 24 h) or starch solution (STA; 3 g wheat starch/kg BW per 24 h) in the cecum to induce hindgut acidosis. Rumen fluid was collected from each ewe on the d before and four d after the start of cecal infusion for an ex vivo fermentation. There were four flasks for each ewe with two flasks per substrate. The two substrates were forage-based (FB; 40% grass hay pellet, 35% whole shell corn, 15% dried distiller’s grain, and 10% alfalfa cubes) and concentrate-based (CB; 75% whole shell corn, 15% dried distiller’s grain, and 10% alfalfa cubes). Flasks contained 2.5 grams of substrate and 150 mL of inoculum (2:1 ratio of McDougall’s buffer and rumen fluid). Four sealed ANKOM F57 bags were filled with 0.25g DM of substrate and placed into flasks to determine in vitro dry matter disappearance (IVDMD). The flasks were incubated at 39°C for 24 h, with sample aliquots collected at h 0, 8, and 24 to determine pH, volatile fatty acids (VFA), and ammonia. Data were analyzed using the MIXED procedure of SAS 9.4. For all response variables, values from the run before cecal infusion initiation were included in the model as a covariate. Ammonia, pH, and VFA were analyzed with the effects of treatment, time, and their interaction. For the CB substrate, there was no effect (P = 0.90) of cecal infusion on ammonia concentration; however, there was a time effect (P = 0.01) with h 24 having a greater ammonia concentration than h 8. For the FB substrate, there was a tendency for STA to have lesser (P = 0.10) ammonia than CON. There was no effect (P ≥ 0.78) of cecal infusion treatment on pH for both substrates; however, there was a time effect (P = 0.01) with pH decreasing over time. In both substrates, there were no effects (P ≥ 0.23) of cecal infusion treatment on IVDMD, VFA concentration, acetate, or propionate molar concentration. However, butyrate molar concentration tended to be less (P = 0.07) for STA ewes for the CB substrate. No treatment differences were observed in butyrate for the FB substrate (P = 0.35). Results indicate that induced hindgut acidosis in sheep did not affect rumen fermentation ex vivo.
PSII-4 Temperature preference of nursery pigs housed in groups by weaning weight quartile
Authors: Morris Jenny , Ellis Mike , Shull Caleb M
Published: May 2024

There is a lack of recent research investigating the temperature requirements of pigs housed in groups with the genetics and management practices currently being used in commercial production. The objective of this study was to establish the preferred temperature of pigs housed in groups with uniform body weight (BW) over the first 4 wk after weaning (at 21 ± 1 d). The study involved 320 newly-weaned pigs that were kept in mixed-sex pens (barrows and gilts) of 20. Three temperature treatments were compared: 26°C vs. 30°C vs. 34°C. The temperature treatments were created in 3 distinct zones of each pen using a heat lamp suspended over an insulated mat and pigs had free access to each zone. Room temperature was set at 22°C for the duration of the study. The population of pigs was divided into weaning-weight quartiles (Quartile 1, 2, 3, and 4, lightest to heaviest; initial BW 4.5, 5.6, 6.5, and 7.7 ± 0.4 kg, respectively; final BW 12.8, 14.4, 16,3, and 18.2 ± 2.0 kg, respectively). The weight quartiles were kept in different pens. The pigs had ad libitum access to nursery diets throughout the study period formulated to meet the requirements proposed by NRC (2012). Cameras captured images of the pen area every 15 min during the study period. The location (in the temperature treatment zones or other areas of the pen) and posture (lying, sitting, and standing) of every pig in the pen were recorded from the images. The ambient temperature in the temperature treatment zones and other areas of the pen were recorded every 2 h throughout the study period using a thermal camera. The preferred temperature was calculated by weighting the percentage of observations of pigs located within each temperature treatment zone and the other areas of the pen by the average temperature in each zone and area. The percentage of observations of pigs in the 26, 30, and 34°C temperature treatment zones for the overall period were: Quartile 1 (15.3, 15.2, and 42.9%, respectively), Quartile 2 (5.3, 23.1, 39.8%, respectively), Quartile 3 (8.5, 15.7, and 41.2%, respectively), and Quartile 4 (5.0, 34.0, and 25.9%, respectively). The calculated preferred temperatures for the weight quartiles for each week of the study are summarized in Table 1. The preferred temperature for the overall period was 30.0, 30.3, 29.3, and 28.6°C for Quartiles 1, 2, 3, and 4, respectively. The impact of housing nursery pigs at these temperatures on pig performance needs to be established.
PSII-5 Temperature preference of nursery pigs housed in groups with mixed body weight
Authors: Morris Jenny , Ellis Mike , Shull Caleb M
Published: May 2024

Current recommendations for ambient temperatures for newly weaned pigs are based on historical research carried out many years ago. Since that time, significant changes have occurred in the genotype of the pigs, as well as in management and housing conditions. The objective of this study was to establish the preferred temperature of groups of pigs, with typical variation in body weight (BW), over the first 4 wk after weaning (at 21 ± 1 d). The study involved 120 newly weaned pigs housed in mixed-sex pens (barrows and gilts) of 20. Three temperature treatments were compared: 26°C vs. 30°C vs. 34°C; the 3 treatments were available to the pigs within each pen. The temperature treatments were created in 3 distinct zones of the pen using a heat lamp suspended over an insulated mat. Room temperature was set at 22°C for the duration of the study. Initial and final BW were 6.2 ± 0.9 kg and 15.3 ± 2.4 kg, respectively. Throughout the study period, the pigs had ad libitum access to nursery diets formulated to meet NRC (2012) requirements. Images of the pen area were captured every 15 min during the study period. The location (in the temperature treatment zones or other areas of the pen) and posture (lying, sitting, or standing) of every pig in the group were recorded from the images. The ambient temperature in the temperature treatment zones and other areas of the pen were recorded every 2 h throughout the study period using a thermal camera. The preferred temperature was calculated by weighting the percentage of observations of pigs located within each temperature treatment zone and the other areas of the pen by the average temperature in each zone and area. The percentage of observations of pigs in the 26, 30, and 34°C temperature treatments areas were: Wk 1 [10.5, 23.1, and 44.2% (SEM 10.70), respectively], Wk 2 [7.8, 25.8, and 44.6% (SEM 5.00), respectively], Wk 3 [7.6, 24.0, and 34.1% (SEM 4.89), respectively], and Wk 4 [12.3, 21.2, and 26.8% (SEM 4.28), respectively]. The calculated preferred temperatures were 31.1, 31.7, 29.6, and 27.7°C for week 1, 2, 3, and 4 post-weaning, respectively. The impact of housing nursery pigs at these temperatures on pig performance needs to be established.
PSII-1 Bacillus-based probiotic supplementation to sows and weaned progeny help to support live performance and manage gross lung lesions in a nursery H1N2 Influenza challenge
Authors: Kinsley Keith P , Mueller Adam , Bertram Mark J , Hansen Lea Hubertz B , Lerner Steve P
Published: May 2024

Recent studies have indicated that providing an effective probiotic to dams and their progeny allows the pigs to respond more favorably to viral challenges (Lerner et al., 2020; Bertram et al., 2022). Sixteen pregnant dams (parity 1 to 5) allotted by gestation pen were exposed to one of two treatments: Control (CON) where dams consumed a standard, non-probiotic containing, gestation and lactation diet or Bacillus (BAC) where dams consumed standard diets with a daily top dress applied to achieve 1.65 x 106 CFUs of Bacillus/gram of complete feed from 5 weeks before farrowing through lactation. Ninety-six nursery pigs were allotted (48 per treatment group) to the nursery portion of this study at weaning. The CON pigs selected for the nursery received non-probiotic containing feed and BAC pigs selected for the nursery received 1.10 x 106 CFUs Bacillus/gram of complete feed for the 3-wk nursery period of the study. Pigs were separated into 8 pens with 6 pigs per pen by treatment. Individual pig body weights and pen feed intakes were recorded on d 0, 7, 14, and 21. Following 14-d of feed acclimatization post-weaning, all pigs received an H1N2 Influenza viral challenge via intratracheal gavage (Haesebrouck et al., 1986). Clinical signs, including rectal temperatures, respiratory score, abdominal score, and demeanor score we collected daily beginning 1 d before challenge (d 13) through the end of the study. On d 21, following body weight collection, all pigs were euthanized, lungs were removed, and each of seven lung lobes (right and left cranial, right and left middle, accessory, and right and left caudal) were scored on percentage of lobes bearing gross (visible) lung lesions (Halbur et al., 1996). Pigs in the BAC group had better F:G ratios during the pre-challenge (1.177 vs. 1.309, P < 0.01), post-challenge (1.418 vs. 1.633, P < 0.01), and entire growth (1.287 vs. 1.464, P < 0.001) periods, compared with those of the CON group. The percentage of pigs in the BAC group with gross lung lesions in the left and right cranial, accessory, and left and right caudal lung lobes was less than those of the CON group (Table 1). Additionally, total lung lobes with lesions per pig (4.1 vs. 5.3, P < 0.001) were lower in pigs in the BAC group. These data indicate that application of a Bacillus-based probiotic (in this case BioPlus 2B) to sows and subsequently their weaned progeny is associated with better feed efficiency and fewer lung lesions following a challenge with H1N2 Influenza.
PSII-6 The interactive effects of deoxynivalenol and lipopolysaccharides on gut integrity and inflammation in IPEC-J2 cells
Authors: Lu Hang , Simmons Julie , Woodward Adrienne , Horn Nathan
Published: May 2024

The objective of this research is to investigate the interactive effects of deoxynivalenol (DON) and lipopolysaccharides (LPS) on gut integrity and inflammation using porcine intestinal epithelial cell line (IPEC-J2). Three experiments were conducted in this study: Exp 1: cells were treated with control, DON (0.5 ppm) or LPS (10 ug/mL) individually and combination of DON and LPS for 24 h, then measure the Lactate dehydrogenase (LDH) release and interleukin 8 (IL8) production in medium and measure the transepithelial electric resistance (TEER) and FITC-dextran passage rate at the end of each experiment. 2) Treat the cells with control or DON for 24 h, then split the two groups for control or LPS treatment for additional 24 h; same measurements were taken as in experiment 1; 3) Treat the cells with control or LPS for 24 h, then split the two groups for control or DON treatment for additional 24 h; same measurements were taken as in previous experiments. In each experiment, six replications were done. Data were analyzed for the effect of DON, LPS and their interaction. Treatments did not affect the LDH in all experiments except for the high LDH release in the treatment of LPS followed by DON in experiment 3. In experiment 1, DON, LPS or combination of DON and LPS significantly reduced the TEER value by 15.1%, 21.7% and 23.9% respectively with only DON has effect on FITC-dextran passage rate (P < 0.001). LPS significantly increased IL8 secretion in the medium (P < 0.001). In experiment 2, DON or LPS decreased TEER value whereas the cells treated with DON before were more susceptible to LPS (23.6% more reduction compared without DON treatment before). Similarly, the FITC-dextran passage rate was also increased by LPS in the cells exposed to DON before (P < 0.05). In addition, LPS significantly increased IL8 secretion no matter the cells was exposed to DON before. In experiment 3, DON or LPS decreased TEER value (P < 0.05) and cells treated with LPS before were more susceptible to DON (11.8% more reduction compared with no LPS treatment before). However, only DON increased FITC-dextran passage rate. The secretion of IL8 increased by DON or LPS with greatest secretion when cells treated with DON which exposed to LPS before (P < 0.05). In conclusion, the results suggested that cells were more susceptible to LPS when the cells were exposed to DON before or vice versa, and the synergetic effect is limited when LPS and DON were added to cells simultaneously.
PSII-3 Evaluation of a microneedle patch for the delivery of meloxicam in a veterinary application
Authors: Midkiff Kirsten A , Miranda-Muñoz Katherine , Cheek Robin A , Reynolds Jana L , Tsai Tsungcheng Cheng , Bear Misty , Kompalage Kushan Pamoda Kompale , Tucker Ryan , Coetzee Hans F , Kegley Beth B , Almodovar Jorge , Powell Jeremy G
Published: May 2024

In the livestock industry, animals undergo painful procedures such as castration and these practices have received increased scrutiny and concern regarding animal welfare. Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used to treat pain and inflammation in livestock. Novel administration routes such as transdermal drug delivery using polymeric biodegradable microneedle patches that are being developed to deliver drugs in a less stressful method. Therefore, the objective of this study was to evaluate meloxicam plasma concentrations when drug was delivered using a microneedle patch. Nursing pigs (n = 7; body weight = 3.69 ± 1.12 kg) from 1 litter were stratified into 1 of 3 treatment groups. Treatments were: 1) 0.5 mg of meloxicam/kg of body weight via oral drench (n = 2; oral); 2) a patch devoid of meloxicam (n = 1; placebo); or 3) 2.5 mg of meloxicam/kg of body weight delivered via microneedle patch (n = 4; patch). During the study, pigs remained in the crate with the sow and littermates. Blood was collected via jugular venipuncture for plasma analysis at 0, 8, 24, 48, and 72 h. An Estrotect Breeding Indicator strip was used to adhere the microneedle patch on the ear of the pigs. Briefly, the strip was cut to the size of the ear, a microneedle patch was placed at the center, and these were applied on the pinna of the ear after blood collection at 0 h. Statistical analyses were performed using the MIXED procedure of SAS 9.4 (Cary, NC) to assess the effects of treatment, time, and treatment × time interaction. Statistical significance was determined at P ≤ 0.05, with tendencies at 0.05 < P ≤ 0.1. There was a treatment × time interaction (P = 0.0074), with the pigs that received oral meloxicam having greater meloxicam plasma concentrations at 8 h compared with pigs that received a placebo patch or a patch containing meloxicam (P < 0.0001). There were no differences in plasma meloxicam concentrations between pigs receiving a placebo patch or a patch containing meloxicam (P = 0.9). Plasma levels of meloxicam were detectable but low in pigs that received a microneedle patch (0.91 ng/mL). Research is continuing to determine the ideal microneedle patch polymer and structure that would deliver meloxicam to achieve desired plasma concentrations.
PSII-2 Effect of piglet processing and castration on growth performance in feeder pigs
Authors: Church Emily R , Carpenter Benjamin , Privett Grady A , Holder Amanda
Published: May 2024

Early in life castration in swine is a common practice to improve muscle and fat deposition and avoid “boar taint”, which is caused by production of androsterone and skatole within the intact male. The objective of this study was to evaluate the effect of performing piglet processing and castration on the same day compared with a 2-d protocol processing on d 1 and castrating on d 7. To determine the effect of processing protocol on subsequent growth in piglets, 42 piglets were randomly assigned at birth to one of two processing protocols: d 3 processing (“early”) or d 1 and d 7 processing (late). For both castration dates, males were castrated using the open method of castration. A sterile scalpel blade was used to make two vertical cuts posterior to each testicle before complete removal of each testicle. Both male and female piglets were assigned to a processing protocol, but only male piglets underwent castration as a sterility procedure. Females on the same processing protocol were subject to similar processing methods and vaccinations but were not sterilized. Body weights were collected on all piglets at d 1, 3, 7, 14, 21, 28 (weaning), and 56. For males, vocalization during the castration procedure was also recorded and analyzed along with growth and performance measures. At weaning (d 28), the early castrated barrows group weighed significantly more than the late castrated barrows; however, there were no significant differences in the body weight at weaning for the early group (males + females) as a whole compared with the late group (males + females) as a whole. This indicates that while males benefited from an early castration and were able to gain more body weight during the pre-weaning phase when processing occurred on d 3 rather than on d 1 and 7, females undergoing two processing dates gained less body weight between birth and weaning.
PSIII-3 Evaluation of remote detection of heart rate, respiratory rate, and body temperature for improved detection of bovine respiratory disease in high-risk receiving calves
Authors: Cheek Robin A , Kegley Beth B , Reynolds Jana L , Ijaz Scott , Midkiff Kirsten A , Powell Jeremy G
Published: May 2024

The objective of this study was to evaluate the effectiveness of the VetGuardian remote monitor to create data-driven detection of bovine respiratory disease (BRD) by identifying vital sign abnormalities for early disease detection. Male calves (n = 20, initial body weight = 213 ± 3 kg) were purchased from regional auction markets and shipped to the University of Arkansas Stocker Receiving Unit. Upon arrival, calves were weighed, branded, received an identification tag, vaccinated, dewormed, and bulls were castrated. On d 1, the remote sensor was used to monitor all calves while restrained in the chute system detecting their body temperatures, and heart and respiratory rates. The remote sensor was placed in 1 of 2 locations for recordings: 1) in front of chute to capture the head, or 2) on the side of chute capturing the torso. Each calf was assigned to a scan location (10 calves/scan location). For all calves, rectal temperatures were also recorded manually, and heart and respiratory rates were determined by thoracic auscultation. Before processing and for the following 28 d, cattle were observed daily for clinical BRD. If presenting symptoms of BRD and if rectal temperature was ≥ 40°C, cattle were deemed morbid and treated with an antibiotic according to a standard preplanned protocol. For any cattle that were examined for BRD the remote sensor was again used for a minimum of 5 min to compare with manual recordings. Statistical analyses were performed using the CORR, MIXED, and MEANS procedures of SAS 9.4 with sex as a random effect and individual calf specified as the subject. There was a positive correlation between manual recordings of rectal temperatures and remote recordings from the head (0.67; P = 0.04) and the side (0.88; P = 0.0008). Remote recordings did not correlate (P ≥ 0.21) with manual recordings for heart rates. However, there was a positive correlation (0.79; P = 0.01) between manual respiratory rates and the side scans, but no relationship (P = 0.16) between manually collected respiratory rates with head scans. LSMeans for temperature data collected manually or by the remote sensor at either location did not differ (P ≥ 0.34). LSMeans for heart rate differed between manual and remote measurements from either location (P ≤ 0.0008). Manual measurements for respiratory rate did not differ (P = 0.26) from remote recordings from the side; however, differed (P < 0.0001) from recordings from the head. In conclusion, the VetGuardian remote sensor varied from manual recordings for heart rates, regardless of sensor location. Scan location had an influence on accuracy of respiratory rate recordings, and body temperature recordings from either location did not differ from manual measurements. Preliminary data should be used for further investigation of this remote sensor.
PSIII-4 Evaluating the variability of the dual sugar absorption test as a measure of intestinal permeability in pigs
Authors: White Cameron S , Greiner Laura L , Tokach Mike D , Woodworth Jason C , Dilger Ryan N
Published: May 2024

The intestinal barrier of pigs can be compromised by many factors including health challenges, off-feed events, and environmental stressors. If dysregulated barrier function is caught early, proper treatment can be initiated to potentially prevent more severe complications to overall health. However, there are few procedures to measure intestinal function in pigs that are both validated, sensitive, and minimally invasive. In this research, the dual sugar test using lactulose and mannitol was conducted on a total of 534 pigs of varying age, sex, body weight (BW), and health status. Each pig received the same oral dose of 500 mg/kg body weight lactulose and 50 mg/kg BW mannitol, and blood was collected either 60 or 240 min following the dose. Plasma concentrations of lactulose and mannitol were quantified by high performance liquid chromatography using validated methods. The ratio of lactulose to mannitol absorption (L:M) served as the indicator of barrier function such that a larger L:M ratio was indicative of greater intestinal permeability. In these pigs, L:M ratios ranged from 0 to 6.96. The median L:M ratio was 0.41 while the average was 0.70, indicating that the distribution of the data was right skewed, influenced by 21.0% of pigs exhibiting a L:M of 0. Collecting blood sooner after oral gavage yielded better detectability as only 2.71% of L:M in pigs from the 60 min group was 0 compared with 43.5% from the 240 min group. Ostensibly, an L:M ratio of 0 is biologically relevant, but interpretation of such values is challenging both from statistical and biological perspectives. Intestinal barrier permeability, absorption kinetics between pigs, and delivery efficiency of the L:M solution may all affect lactulose absorption yielding a ratio of 0. In general, the data werewere highly variable, with a standard deviation of 0.95, so a regression analysis was performed to determine which factors may be influencing this variation. Neither a forward nor a backward elimination model determined any of the five explanatory variables (i.e., BW, timing of blood collection, health status, age, or sex) to be significant. Additional correlational analyses further confirmed that there were no significant interactions. Overall, it appears that these factors do not help to explain the variability in the L:M ratio. Further investigation is warranted to validate this process and understand the source and impact of L:M ratios equaling 0.
PSIII-2 Evaluation of medium-chain fatty acids on just-weaned piglet performance and diarrhea scores: A nursery trial
Authors: MEDINA Bertrand , Bussières Dan , Girard Ivan D
Published: May 2024

Weaning is one of the most stressful events for commercial pigs. The transition from mother’s milk (animal proteins) to a solid diet based on plant proteins, the reduction in lactose intake and the decline in HCl secretion by the digestive system of the piglet result in a sudden and significant increase in stomach pH as well as an increased risk of post-weaning diarrhea. The aim of this trial was to evaluate whether the use of a blend of medium-chain fatty acids (MCFAs) on top-off conventional nursery diets would improve zootechnical performance and intestinal problems in just-weaned piglets. Piglets [n = 624, 21-d of age, 6.5 kg body weight (BW), (♂ Fast Duroc x ♀ Fast 275)] were housed in 26 pens of an experimental nursery. Each pen (24 pigs/pen, with a starting density of 3.0 ft2/pig) was equipped with a height-adjustable water sucker, a water bowl and fitted with a single feeder-bin. Females and males were allocated to each pen, according to 3 BW categories (heavy, medium, and light). During a 46-d period of trial, the piglets (13 replicated pens per treatment) were allotted to a conventional 5 phases feeding program with 2 kg/MT of chlortetracycline (22%) and 400 g/MT of tiamuline (1.78%; CON). These basal diets contained 2,500 ppm Zn in Phases #1, 2, and only 2,000 ppm Zn in phase #3. Phases #1 to 3 were also supplemented with Ca-butyrate (1 kg/MT) and a blend of protected acidifiers (1 kg/MT). The treated group consisted to the basal diet (CON) supplemented with a blend of medium-chain fatty acids (MCFAs) at 1.0 or 0.75 kg/MT for Phases #1, 2,3 and Phases #4, 5, respectively and supplying of a proprietary blend of caprylic, capric, and lauric acids. Daily feed consumption, weekly pig pen BW, dead and removed pigs and daily diarrhea evaluation index were completed. Data are analyzed by an ANOVA model including treatment and pen as fixed and random effects, respectively. Pairwise comparisons were completed with a Chi-square test. The overall results are presented in Table 1. At the end of wk 2 and 3, animals receiving MCFAs had a better average daily gain (ADG; P < 0.05) than CON. Therefore, at wk 2, 3 and 4, MCFAs animals BW were heavier than CON ones (P < 0.05). Average daily feed intake (ADFI) was not significantly different for the overall duration of the trial (P > 0.05). However, at weeks 2 and 3, MCFAs piglets had a greater ADFI than CON ones (P < 0.05). The daily diarrhea index of the MCFAs group was less than CON at wk 3 (P < 0.05). In this trial, the significant improvement of diarrhea index on just-weaned MCFAs treated piglets could explain the significant better growth during the first 3 wk of nursery.
PSIII-1 Clinical benefits of an in-water essential oil blend on antibiotic-free pigs with post-weaning diarrhea: A field study
Authors: Greaves Gillian , LICHTY Clint , Wagner Ashley L , MEDINA Bertrand , Girard Ivan D
Published: May 2024

Post-weaning diarrhea can be costly for producers, especially in antibiotic free production flows (RWA), where the use of antimicrobials leads to a loss of valuable premiums on individual pigs. This field study examined the impact of an in-water essential oil blend on RWA pigs with post-weaning diarrhea using pen-level diarrhea scores, and percentages of diarrhea-related sick, fallback and removed pigs. A total of 3,598 pigs (~4 wk of age, mixed sex) in 73 pens from 2 RWA flows and 4 pig turns (2 turns per nursery barn) were enrolled. Sow sources were known to experiencing mild E. coli and/or rotavirus associated post-weaning diarrhea. In each barn, one-half of the pens were assigned to control (regular water) or treatment [AQUAGUTSWINE, at 250 mL/1000 L drinking water, a flavored liquid Vitamin C Supplement) designed by Probiotech International Inc. and supplying Star Anise, cinnamaldehyde oil blend and ascorbic acid (2,955 mg/kg)] for ~2 wk post weaning. Pen-level diarrhea was assessed every other day (scale from 0 to 4). Additionally, diarrhea-related sick pigs were assessed individually at the same time pen-level diarrhea was scored. In each pen, a pig was first identified as sick (sunken eyes, poor gut fill or lethargic/depressed) and then confirmed if it had diarrhea. Diarrhea-related fallbacks were assessed at the end of treatment (~2 wk post-weaning). A pig was considered fallback if it did not recover from its enteric problem (Previously marked as a diarrhea-related sick pig) by the end of the treatment. A diarrhea-related removal was a previously marked diarrhea-related sick pig that was removed from its pen. Mild post-weaning diarrhea related to E. coli and rotaviruses occurred in both flows. Overall, the VHP reduced pen-level diarrhea scores over time (1.2 vs 1.5, P < 0.01), and percentages of diarrhea-related sick (10.9 vs 14.3%, P = 0.36), fallback (3.5 vs 4.6%, P = 0.10) and removed pigs (0.17 vs 0.30%, P = 0.12) compared with the control group. These first results suggested that AQUAGUTSWINE could be an aid in reducing clinical impact of mild post-weaning diarrhea caused by E. coli and rotavirus in RWA pigs.
PSIII-6 Tail damage caused by tail biting in growing-finishing pigs housed in two group sizes
Authors: Li Yuzhi , Archer Courtney , Hilbrands Adrienne , Schmidt Ty B , Mote Benny E , Johnston Lee J
Published: May 2024

Tail biting can compromise the welfare of pigs and cause economic losses for pork producers, but little is known about the development of tail biting and its resulting impact on pigs. In this study, we investigated victimization by tail biting and the resulting impacts on the welfare and performance of pigs housed in two group sizes. Pigs (n = 432, initial body weight = 22.0 ± 3.7 kg) with intact tails were housed in large (LG = 18 pigs/pen, 12 pens) or small groups (SG = 9 pigs/pen, 24 pens) in a barn with fully slatted floors for 14 wk until market weight (120.7 ± 11.8 kg). Floor space (0.76 m2/pig) and feeder space (4 feeder spaces/9 pigs) allowance were identical between group sizes, and pigs were stratified by initial body weight and sex across treatment pens. Growth performance, pig removal, and tail damage were monitored throughout the study. Tail damage was assessed for each pig weekly and during tail biting outbreaks, using a subjective scoring system (0 = no damage; 1 = healed lesions with small scabs; 2 = puncture wounds with visible blood; 3 = wounds with signs of infection; 4 = partial or total loss of the tail). The maximal tail score (MTS) each pig received every four weeks and over the entire 14 weeks was summarized. Pigs that received MTS of ≥ 2 were considered victimized by a tail biter. Data were analyzed using Glimmix procedure with logit function and FREQ procedure with chi-square and CMH test of SAS software. Compared with SG, LG had greater MTS during the initial 4 wk (1.1 vs. 0.8, chi-square = 17.9, df = 1; P < 0.001) and reduced MTS during the last 2 wk (0.7 vs. 0.9, chi-square = 4.8, df = 1; P = 0.03), suggesting that tail damage declined as pigs grew in LG, but not in SG. The number of pigs removed for tail biting tended to be less and those removed for death and sickness tended to be greater in LG than in SG (chi-square = 7.4; df = 3; P = 0.06). Across group sizes, 68% of the removed pigs (n = 28) were victimized by tail biters (MTS ≥ 2). Between group sizes, there was no difference in time to first victimization or how often individual pigs were victimized throughout the study. Across group sizes, 45% of pigs were never victimized, but 22%, 16%, and 9% were victimized 1, 2, and 3 times, respectively. Eight percent of pigs were victimized more than three times, including 6% with MTS of 3 or 4. Pigs with MTS of 4 over the entire study period were three times more likely (odds ratios between 3.18 and 3.70; all P ≤ 0.03; Table 1) to have market weight lower than the average compared with other pigs. Based on these results, we suggest that management strategies should prevent multiple victimizations or tail loss to maintain pig welfare and performance.
PSIII-5 Impact of multiple suckling of litters during lactation on pre-weaning piglet performance
Authors: Gainey Noah , Shull Caleb M , Ellis Mike
Published: May 2024

Multiple suckling involves the grouping of sows and litters so that piglets can suckle from all sows in the group. This approach could potentially reduce pre-weaning mortality and increase weaning weight. The objective of this study was to evaluate the effects of multiple- compared with single-suckling (Piglets having access to only one sow) on piglet pre-weaning performance. The study was carried out in a commercial farrowing facility using a RCBD (35 blocks; total of 210 litters and 2950 piglets). Blocking factors were farrowing date, sow parity, body condition score, and number of functional teats. Two treatments were compared: 1) Control (sow and litter kept in an individual farrowing crate/pen); 2) Multiple Suckled (group of 3 sows in individual crates with piglets having access to all 3 sows). The Multiple Suckled treatment was created at 5 d after birth by removing the pen dividers between 3 adjacent farrowing pens with the sows remaining in the farrowing crates. The study started at d 5 after birth and ended at weaning (19 ± 2 d of age). Piglet weights were collected after cross-fostering and at the end of study; all piglet mortalities were recorded. Data were analyzed using the glmer and lmer functions of R 4.2.1. The model included the fixed effect of treatment and the random effect of block. Average piglet weight at the end of study (5.11 vs. 5.18 kg, respectively) and average daily gain from start to end of study (191.4 vs. 195.2 g/d, respectively) were similar (P > 0.05) for the Multiple Suckled and Control treatments (Table 1). There was no difference (P > 0.05) between the treatments for pre-weaning mortality. These results suggest that under the conditions of this study there was no benefit in piglet pre-weaning performance from multiple compared with single suckling of litters.
PSII-8 Analysis of maternal influence on phenotypic ultrasound measurements of weaned Angus calves
Authors: Phelps Sarah L , Dahlke Garland , Reynolds Mary E , Culbertson Miranda
Published: May 2024

Ultrasound carcass data can be used to accurately estimate the body composition of beef cattle in comparison with a body composition score. Literature regarding the analysis of phenotypic carcass data has focused predominately on yearling or mature cattle with limited measurements on weaned calves. Therefore, the influence of the milking ability of the dam on body composition traits measured via carcass ultrasound is unknown. The objective of this study was to estimate correlations between the maternal influence of the dam on the phenotypic ultrasound measurements of the calf. To quantify maternal influence, the expected progeny difference (EPD) for milk (MILK) of the dam was correlated to three ultrasound measurements of the calf: backfat thickness (BFAT), ribeye area (REA), and intramuscular fat (IMF). Ultrasound measurements were collected 1 wk after weaning on 104 purebred Angus heifer calves from the Iowa State University McNay Memorial Research and Demonstration Farm located outside Chariton, Iowa. The average age and body weight for heifers were 187 d and 195 kg, respectively. The milk EPD of the dam was correlated to the ultrasound measurements taken on the calves. For each trait, Pearson’s correlations were calculated between the ultrasound traits of the calf to the dam’s milk EPD using R Statistical Software version 4.3.1. A small positive correlation was identified between MILK and REA (r = 0.28, P = 0.004). This suggests a weak phenotypic relationship between MILK and REA for weaned heifers. The correlation between MILK to BFAT and IMF was 0.10 (P = 0.318) and -0.05 (P = 0.619), respectively. These correlations were not significantly different from zero. This suggests the potential for milk production of the dam has little association with BFAT and IMF for weaned heifers. Although further research is needed, the results from this study indicate little to no relationship between milk EPD of the dam on ultrasound measures of the calf for BFAT, REA, and IMF.
PSII-9 Whole genome sequences of two nitrate-reducing strains of Selenomonas ruminantium isolated from the rumen
Authors: Costello Margaret K , Ricke Steven C , McClure Jennifer , Anderson Robin C
Published: May 2024

Selenomonas ruminantium is a functionally diverse, non-fibrolytic member of the rumen microbial community with two subspecies: lactilytica and ruminantium. Some strains of S. ruminantium can reduce nitrate and nitrite, which may be associated with ruminal fiber degradation and, thus, greater forage diets. Most work done with S. ruminantium has been culture-based, with less genomic and functional data. Here, we performed whole genome sequencing with an Oxford Nanopore GridION on two isolated, nitrate-reducing strains of S. ruminantium to provide complete genomic data and determine the nitrogen usage functional capacities of these novel strains. The two isolated strains, 223 and 231, were shipped on dry ice to the University of Wisconsin-Madison, where they were grown, pelleted, and observed under a microscope to determine purity. The samples were processed with a 3 min bead-beating step before extraction with the Zymo Quick-DNA High Molecular Weight MagBead Kit. Subsequently, the extracted samples underwent a quality assessment step before moving into library preparation for Oxford Nanopore sequencing. The two libraries were then loaded onto two R9.4.1 flow cells per library and were sequenced on an Oxford Nanopore GridION for 72 h. The data were extracted from the GridION, and the combined passed reads from each of the two flow cells per library were assembled with Canu and Flye, long-read de novo genome assemblers designed for noisy, single-molecule sequences. The assembled genomes were compared with a reference S. ruminantium genome with Quast, a quality assessment tool that evaluates assembly accuracy. Finally, the assembled genomes with the highest accuracy were analyzed with prodigal to generate protein-coding gene predictions and then with BLAST to assign functional predictions. For each strain, a different assembly was used. The Canu assembly of strain 223 had greater accuracy rates at 3205.23 mismatches per 100 kbp, while the Flye assembly of strain 231 had 2494.40 mismatches per 100 kbp. The two strains had similar genome sizes: 3,098,553 base pairs for strain 223 and 3,138,614 base pairs for strain 231. Strain 223 had less GC content than strain 231 of 51.02%, while strain 231 had a GC content of 52.80%, which were both less than the 50.68% GC content of the reference genome. These genomes provide a resource for understanding nitrate reduction in the rumen and work to build a better database for analyzing the rumen microbiome.
PSV-6 The additive effect of hormonal implant and inclusion of beta-agonists in carcass quality in beef cattle
Authors: Tollefson Rebecca L , Winebold Deedra M , Deaton Claire , King Adam , Case Riley , Robertson Joel , Church Emily R , Holder Amanda
Published: May 2024

The objective of this study was to determine what additive effect hormonal implants and inclusion of beta-agonists in the diet have on carcass quality in yearling beef steers. Twenty-one Hereford-cross steers (450 ± 15 kg) were assigned to one of three drylot pens based on initial body weight (BW) and sire so that each pen had an equal starting BW and sires were equally represented in each pen. Each drylot pen was assigned to one of three treatments: receiving a hormonal implant (IMP), consuming a beta-agonist (BAG), or receiving both of the previous treatments (AND). All steers were fed a mixed ration consisting of 30.0% rye silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement (22.0% CP, 2.90 Mcal ME/kg DM). Animals were fed daily at 0700 and 1700 and weighed weekly at 0630. For the duration of the trial, animals were housed in drylot pens with ad libitum access to feed and water and had shade structures in each pen. Following a 15-d adaptation period, feed intake was recorded for 45 d. Weight gain for each treatment group were 1.26, 1.28, and 1.48 kg/d for IMP, BAG, and AND, respectively. After the intake portion of the study was completed, an animal from each pen was slaughtered and evaluated for carcass quality. Hot carcass weights for diets IMP, BAG, and AND were 347.4, 352.9, and 394.8 kg, respectively. Following 14 d aging, samples from the ribeye area were collected from each animal and subjected to sensory analysis and other assessments of quality. Data were analyzed as a completely random design in SAS v9.4. There was not a significant difference between the IMP treatment and the AND treatment based on assessment from Warner-Bratzler shear force, carcass yield, marbling score, and sensory assessment (P < 0.05); however, the BAG treatment had significantly less marbling than the other two treatments. It was concluded that the additive effect of using both a hormonal implant and a beta-agonist can produce carcass of good quality without detrimental effects on meat quality when compared with a beta-agonist only inclusion.
PSV-3 Effects of maternal early gestational weight gain on multigenerational skeletal muscle gene regulation in offspring
Authors: Ramirez-Zamudio German D , Dahlen Carl R , Baumgaertner Friederike , Menezes Ana Clara B , Hurlbert Jennifer L , Bochantin Kerri A , Underdahl Sarah R , McCarthy Kacie L , Reynolds Lawrence P P , Ward Alison , Borowicz Pawel P P , Sedivec Kevin K , Caton Joel S , Diniz Wellison J j S
Published: May 2024

Maternal nutrition during the periconceptional period may have multigenerational effects on the gene regulation of fetal skeletal muscle. This study aimed to investigate the impact of maternal rate of body weight gain (F0) during early gestation on the differential gene expression in the skeletal muscle of newborn (F1) and second-generation fetuses (F2) female offspring. To this end, crossbred Angus heifers (F0) were assigned to either a low gain (LG; 0.28 kg/d; n = 8) or moderate gain (MG; 0.79 kg/d; n = 8) group during the first 84 d of gestation. Subsequently, heifers (F0) were managed as a single group on a forage-based diet until the weaning of the F1 offspring (8 mo). The F1 heifers were estrus synchronized and bred via AI at 15 mo, and F2 fetuses were harvested on d 84 of gestation. Longissimus dorsi muscle was collected at birth (F1) and the 84-d harvest in F1 heifers and their F2 fetuses for multigenerational RNA-Seq analysis. Differentially expressed genes (DEGs) were identified using the DESeq2 R-package. Significant genes were retrieved based on P - value ≤ 0.05 and log2 fold change|0.5|. We previously reported that F1 heifers from MG dams at birth were ~2 kg heavier (P < 0.03), and herein we report the impact on the gene regulation of skeletal muscle in the F1 and F2 generations. At birth, F1 heifers from MG cows exhibited 275 DEGs, of which 98 were downregulated, and 177 genes were upregulated, related to the immune system (TNFAIP3, TLR5), cellular signaling and transduction (RASGRP2, NFE2), and extracellular matrix (TGM3, MMP17). Changes in gene expression persisted in F1 heifers through development, breeding, and until the evaluation at d 84 of gestation. At this time point, we identified 75 upregulated genes out of 177 DEGs. These genes were underlying cellular functions (USP43, PASK), hematopoiesis (THPO), metabolism, and enzymatic activity (SMOX, OAT) as possible metabolic adaptations. Similarly, 102 genes were downregulated, mainly associated with immune and inflammatory response (CHI3L1, LDAF1). Regarding the F2 fetuses, 151 DEGs were differentially expressed. Among them, 63 were upregulated in the MG group and involved with biological functions such as ion channels and transport (KCNAB1, SLC9A3), transcriptional regulation, and signaling (ZNF75D, TMEM106B, DPP6), enzymatic activity, and metabolism (B3GNT4, FAM20A, ALDH5A1, and PRSS23). Likewise, 88 downregulated genes were associated with the cell cycle and proliferation (APOOL, CIR1, and STIL). In conclusion, periconceptional maternal nutrition aimed at moderate weight gains can have multigenerational effects on the gene regulation of fetal muscle tissue.
PSV-4 Exposure to prenatal tributyrin improved pre-weaning growth performance and reduced fat deposition in the muscle of market age pigs
Authors: Cooper Elizabeth , Murray Robert , Palou Rousset , Markley Grace I , Stahl Chad H
Published: May 2024

Organic acids, including short chain fatty acids, medium chain fatty acids, and tricarboxylic acid, are used as alternatives to antibiotics for the purpose of growth promotion in livestock species. Butyric acid has been used extensively for its various functions in intestinal health and barrier function, as well as its actions as a histone deacetylase inhibitor. Many of the issues relating to using butyric acid as a feed supplement are overcome by utilizing tributyrin (TB), a butyrate prodrug. Dietary supplementation of TB to sows during gestation was able to improve pre-weaning litter performance. Sows (n = 52, 42 gestational days) were randomly assigned to either a control diet or control diet supplemented with 2% TB. All diets were made isocaloric with the addition of oil and wheat flour. Dietary treatments continued until 112 d of gestation. After farrowing, piglet growth performance was monitored. Once offspring reached 6 mo of age, 30 gilts from the most median performing litters were identified for tissue collection and evaluation of meat characteristics. Sows that received tributyrin during gestation tended to have greater total litter weights at birth (P < 0.1); however, average individual birthweights were not statistically different between control and TB litters. The TB piglets tended to be heavier at weaning (P < 0.1). Pre-weaning average daily gains were higher in piglets exposed to prenatal TB (P < 0.01). Body weights and hot carcass weights did not differ significantly in gilts at market age. There was, however, a trend of increased dressing percentage from TB treated offspring, accompanied by significantly reduced back fat at the 10th rib (P < 0.1 and P < 0.05 respectively). These data suggest that TB supplementation results in both temporary and permanent improvements to growth and development. This study provides further evidence that prenatal TB can have long term effects on muscle growth and meat quality. Further studies are needed to ultimately determine whether prenatal or postnatal supplementation is ideal for improving long-term growth performance.