bluuebunny/crossref_metadata_2025 huggingface dataset:
66 A novel analytical method for identifying periods of increased mortality in individual wean-to-finish pig barns
Authors: Grohmann Caleb J , Decker Jared E , Shull Caleb M , Lowe Erin J , Hoek Jon , Schnarre Kevin , Polson Dale D
Published: May 2024

Mortality rates in all phases of pork production have increased over the past several years. Decreasing mortality rate is of utmost economic importance to producers, especially in weaning-to-finishing pigs where additional investment in feed, medications, and other inputs are expended. A novel analytical method was used to identify sequences of days of increased mortality, defined as mortality episodes, within cohorts of weaning-to-finishing pigs. Cubic smoothing spline regression equations were estimated between days post placement (DPP) and mortality (total daily number of dead and euthanized pigs) for 42 groups of pigs placed in 12 rooms within 6 barns (2 rooms per barn) in Illinois and Iowa from December 2020 to July 2022 (n = 5,676 observation days). For each group, the instantaneous slope between DPP and mortality from spline regression was calculated and used to identify changepoints [i.e., peaks (negative instantaneous slope at DPPt and positive instantaneous slope at DPPt-1) and valleys (positive instantaneous slope at DPPt and negative instantaneous slope at DPPt-1)]. Within each mortality sequence, the maximum and minimum instantaneous slope were considered the start and end of the mortality episode, respectively. Mortality episodes were only considered high mortality episodes if the following metrics were satisfied: 1) greater than or equal to 1 mortality per day, or 2) greater than or equal to 1/3 of the days in the mortality sequence had at least 1 mortality. Days were classified as “start days” if they were within 1 d from the maximum instantaneous slope; likewise, we classified a day as “end days” if it was 1 d from the minimum instantaneous slope. Any day in between the start and end of a mortality episode were defined as “peak days”, and a “normal day” was all other days that did not fall within the start, peak, or end of a high mortality episode. Least-squares means for predicted mortality from a negative binomial generalized linear model showed that mortality was highest and lowest for peak days and normal days, respectively (3.475 ± 0.1729 and 0.591 ± 0.0156 pigs, respectively; P < 0.05; Table 1). Mortality during start or end days of an episode did not differ from each other (2.185 ± 0.1973 and 2.069 ± 0.1881 pigs, respectively; P > 0.05; Table 1) but were significantly greater and lower than a normal or peak day, respectively (P < 0.05; Table 1). The proposed analytical method provides more precise classification of mortality episodes in pig cohorts than previously proposed methods. Results from this method can be used in models to predict the start of mortality episodes, providing ample time for intervention to reduce the overall number of dead pigs in wean-to-finish pig production.
73 Effects of blend of organic acids and monoglycerides on immune responses of weaned pigs experimentally infected with enterotoxigenic Escherichia coli F18
Authors: Park Sangwoo , Chen Ying , Wolfenden Ross , Liu Yanhong
Published: May 2024

Our previous research implies that dietary supplementation of organic acids blend, monoglycerides blend, and the combination of both can mitigate diarrhea of weaned pigs infected with Escherichia coli (E. coli) F18. The objective of this study was to investigate the effects of dietary supplementation with a blend of organic acids, a blend of monoglycerides, or the combination of both on immune responses of weaned pigs experimentally infected with E. coli F18. Forty pigs [average body weight (BW) = 7.81 ± 0.84 kg] were individually housed and randomly assigned to one of four treatment groups with 10 replicate pigs per treatment. The four dietary treatments were: () Control: nursery basal diet, 2) Acids: basal diet supplemented with a blend of organic acids (formic acid, lactic acid, and sodium formate) at 0.3%, 3) Monoglycerides: basal diet supplemented with a blend of monoglycerides of fatty acids at 0.3%, or 4) Combination of acids and monoglycerides: basal diet added with the acids blend at 0.2% and the monoglycerides blend at 0.2%. The experiment lasted 28 d, with 7 d before and 21 d after the first inoculation (d 0). All pigs were orally inoculated with E. coli F18 (1010 CFU/3 mL) for 3 consecutive days from d 0. Serum samples were collected on d 0, 2, 5, and 14 post-inoculation (PI) to measure the concentration of C-reactive protein (CRP) and haptoglobin using ELISA. Porcine Cytokine/Chemokine13-Plex Discovery Assay (Eve Technology, Canada) was also conducted with serum samples from d 0, 5, and 14 PI. Data were analyzed by ANOVA using PROC MIXED of SAS with a randomized complete block design. The concentrations of serum CRP and haptoglobin were increased (P < 0.0001) on d 2 PI and then gradually decreased on d 5 and 14 PI. However, no differences were observed in serum CRP and haptoglobin concentrations among all treatment groups throughout the experiment. Pigs fed with monoglycerides tended (P < 0.10) to have decreased serum granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 1-alpha (IL-1α), and tumor necrosis factor-alpha (TNF-α) concentrations on d 0 PI compared with other treatments. Pigs supplemented with monoglycerides also tended (P < 0.10) to have decreased GM-CSF on d 5 PI and less IL-1α on d 14 PI among all treatments. Supplementation of the combination tended (P < 0.10) to have greater GM-CSF concentration on d 5 PI compared with other treatments. In conclusion, dietary supplementation of monoglycerides blend or the combination of organic acids and monoglycerides alleviates systemic inflammation of weaned pigs during E. coli F18 infection by modulating related cytokines. However, additional research is needed to understand the modulation mechanisms.
63 Impacts of dietary myristic acids on mucosa-associated microbiota in relation to intestinal health and growth parameters of nursery pigs
Authors: Choi Hyunjun , Rocha Gabriel C , Kim Sung Woo
Published: May 2024

This study investigated the evaluate the role of dietary myristic acid on mucosa-associated microbiota for their relevance to intestinal health and growth performance of nursery pigs. A total of 36 newly weaned pigs [6.6 ± 0.4 kg body weight (BW)] were assigned to 3 treatments (n = 12/treatment) using a randomized complete block design with initial BW and sex as blocks. Pigs were fed for 35 d in 3 phases (10, 10, and 15 d, respectively). Treatments were 1) NC: basal diet; 2) PC: NC + 0.03% bacitracin in all phases; and 3) MA: NC + myristic acid complex at 0.20% in phases 1 and 2 and 0.12% in phase 3. Pigs were euthanized to collect jejunal mucosa and jejunal tissues for microbiome sequencing and measuring intestinal health parameters. Data were analyzed using preplanned contrasts (NC vs. PC and NC vs. MA) in the Proc MIXED procedure and correlation coefficients between microbiota and the intestinal health parameters were determined by the CORR procedure of SAS. The PC increased (P < 0.05) Lactobacillaceae (22.2 to 55.1%) compared with NC. The MA increased (P < 0.05) Veillonellaceae (1.7 to 5.2%), Lachnospiraceae (0.3 to 3.6%), Coriobacteriaceae (0.6 to 1.5%), and Ruminococcaceae (0.5 to 2.1%) and tended to increase (P = 0.072) Bifidobacteriaceae (6.9 to 18.2%) compared with NC. The PC increased (P < 0.05) Simpson (0.72 to 0.89) index and the MA increased (P < 0.05) Chao1 (124.3 to 221.0), Shannon (3.4 to 5.0), and Simpson (0.7 to 0.9) indexes compared with NC. The relative abundance (RA) of Helicobacteraceae was positively correlated with IL-8 (r = 0.63; P < 0.05) and protein carbonyl (r = 0.65; P < 0.05). The RA of Bifidobacteriaceae was negatively correlated with IgG (r = -0.51; P < 0.05), IL-8 (r = -0.58; P < 0.05), TNF-α (r = -0.46; P < 0.05), and protein carbonyl (r = -0.64; P < 0.05) whereas it was positively correlated with average daily gain (ADG; r = 0.51; P < 0.05) and average daily feed intake (ADFI; r = 0.49; P < 0.05). The RA of Lactobacillaceae negatively correlated with IL-8 (r = -0.59; P < 0.05) and protein carbonyl (r = -0.54; P < 0.05) whereas it was positively correlated with ADFI (r = 0.43; P < 0.05) and MDA (r = 0.44; P < 0.05). The RA of Veilonellaceae and Megasphaera sp were negatively correlated (r = -0.49; r = -0.61; P < 0.05) with IgG, respectively. In conclusion, MA mainly increased RA of Bifidobacterium and Megasphaera, whereas PC increased RA of Lactobacillus and Mitsuokella in the jejunal mucosa. The positive modulations of RA of mucosa-associated microbiota by PC and MA were strongly correlated with improved intestinal health and growth of nursery pigs.
77 Healing progression of tail docking and ear tag wound in lambs
Authors: Wood Jocelyn M , Adcock Sarah J
Published: May 2024

Tail docking and ear tagging are common husbandry practices in lambs, but little is known about the healing process of the resulting wound. Additionally, evidence in other species shows that concurrent injurious procedures may delay wound healing. Thus, the objectives of this study were to 1) describe wound healing following tail docking and ear tagging, and 2) compare healing of ear tag wound in docked and undocked lambs. Within 28 Polypay female twin pairs, one lamb was docked by placing a constrictive rubber ring on the tail 24 to 48 h after birth and the tail of the other lamb was left intact (n = 28/treatment). Plastic-tipped ear tags were applied to both ears of all lambs immediately before tail docking. Wound photos of the ears and tail were taken twice weekly until weaning, resulting in 16 to 22 observations per lamb. Tail wound photos were analyzed to determine when the tail fell off and to score the presence of 6 tissue types: pus, serous exudate, sanguineous exudate, granulation, crust, and slough. A healed tail or ear wound was defined as one that was fully contracted, and no other tissue types were present. Tails took 19 ± 2 d to fall off (mean ± SD; range = 16 to 25 d) and their wound took 41 ± 8 d to heal completely (30 to 60 d). The prevalence of any of the 6 tissue types did not predict how long it took the tail wound to heal (F < 2.50, P > 0.13). Tissue types, indicative of possible infection, such as pus and slough, were present at least once in 89% and 93% of the docked lambs and in 8% and 10% of the total sampling periods, respectively. On average, pus and slough first appeared 12 ± 4 d (range = 5-22) and 11 ± 3 d (5-15) after docking, respectively. Of the 112 ear wounds, only 16% had healed by the time the lambs were weaned (55 to 74 d after tagging). Contrary to our predictions, there was a tendency for more docked lambs to have at least one healed ear wound by the end of the sampling period compared with undocked lambs (11 docked lambs vs 4 undocked lambs; X2 = 3.28, P = 0.07). This may be a result of an increased systemic inflammatory response and possible reduction in activity in the docked lambs. Overall, most ear tag wounds were still not healed after 2 mo, and tail wound took over 1 mo to heal. Further research is needed to determine the welfare implications of routine husbandry practices in sheep, including pain experienced during healing and how other factors may affect the healing process.
75 Diet acid-binding capacity-4 influences nursery pig performance and fecal dry matter
Authors: Stas Ethan , Tokach Mike D , Woodworth Jason C , DeRouchey Joel M , Goodband Robert D , Gebhardt Jordan T
Published: May 2024

A total of 360 pigs (initial body weight = 5.9 kg) were used to evaluate the effects of increasing acid-binding capacity-4 (ABC-4) of the diet on nursery pig performance and fecal dry matter (DM). At weaning, pigs were allotted to 1 of 6 dietary treatments. There were 5 pigs/pen and 12 replications/treatment. Pigs were fed experimental diets in two phases with phase 1 from d 0 to 10 post-weaning followed by phase 2 from d 10 to 23. Diets were formulated with increasing ABC-4 levels ranging from 150 meq/kg (diet 1, low ABC-4) to 312 meq/kg (diet 5, high ABC-4) in phase 1 and 200 meq/kg (diet 1, low ABC-4) to 343 meq/kg (diet 5, high ABC-4) in phase 2. For diet 1, low ABC-4 diets were formulated using specialty soy protein concentrate (AX3 Digest; Protekta; Newport Beach, CA) at 12.5 and 10.0% of the diet in phase 1 and 2, respectively. The low ABC-4 diet also utilized fumaric and formic acid at 0.50 and 0.48% of the diet, respectively, for both phase 1 and 2. For diets 2 (medium low), 3 (medium), 4 (medium high), and 5 (high), increasing dietary ABC-4 was achieved by progressively decreasing the level of acidifiers and replacing specialty soy protein concentrate with enzymatically treated soybean meal (HP 300; Hamlet Protein; Findlay, OH) on an SID Lys basis. Diets 1 through 5 were formulated without the addition of pharmacological levels of Zn from ZnO. For diet 6, a positive control diet was used which had the same formulation as the highest ABC-4 diet but with the addition of 3,000 and 2,000 mg/kg of Zn from ZnO in phase 1 and 2, respectively. Following phase 2, all pigs were fed a common diet until d 38 of the study. In the experimental period and overall, there was a quadratic response observed (P ≤ 0.030) where body weight (BW) and average daily gain (ADG) were greatest for pigs fed the medium low and medium ABC-4 diets (Table). During the experimental period, increasing ABC-4 decreased (linear, P = 0.002) gain to feed ratio (G:F). For overall G:F, a quadratic response was observed (P = 0.023) where G:F was most improved for pigs fed the medium low and medium ABC-4 levels. For fecal DM, increasing ABC-4 decreased (linear, P ≤ 0.036) fecal DM on d 10 and 17, with no differences on d 23. Pigs fed the diet with pharmacological levels of Zn from ZnO had increased (P ≤ 0.038) ADG compared with pigs fed diets without ZnO during the experimental period and overall. In summary, a dietary ABC-4 level of 203 and 247 meq/kg for phase 1 and 2, respectively, was most beneficial to improve both growth performance and fecal DM in weanling pigs.
74 Feeding style and its influence on growth, circulating insulin, and spatial preference of young pigs
Authors: Sommer Kaitlyn , Sutkus Loreta , Golden Rebecca , Dilger Ryan N
Published: May 2024

In this study, we investigated the influence of feeding style on growth performance, circulating insulin concentrations, and spatial preference within the home-cages (HC) of young pigs. Pigs (n = 43 boars) were weaned on postnatal day (PND) 2, allotted to treatment based on litter of origin and body weight (BW), and reared artificially over a 15-d period. Pigs were provided a nutritionally adequate milk replacer 20 h per day using one of two feeding styles: 1) ad libitum (i.e., continual access to milk replacer), and 2) prescribed [330 mL/kg of BW from PND 3-7 (wk 1), and 357.5 mL/kg of BW from PND 8-18 (wk 2)]. In addition to water in the reconstituted milk replacer, free choice access to fresh water was provided throughout the study. Milk intake (i.e., disappearance) and BW were recorded daily, with pigs undergoing continuous top-down video surveillance throughout the study. On PND 17, blood was collected from a subset of pigs (n = 24) for quantification of insulin concentrations. Video analysis of pigs (n = 43) was performed to establish time spent in each HC quadrant. All data were analyzed via a 1-way ANOVA using the MIXED procedure of SAS. During wk 1, ad libitum pigs exhibited increased (P < 0.05) average daily BW gain (152 g/d) and average daily milk intake (728 g/d) compared with the prescribed treatment (127 g/d and 570 g/d, respectively). This same effect continued in wk 2 for average daily BW gain and average daily milk intake, with ad libitum-fed pigs consuming more (P < 0.05) milk replacer (256 g/d and 1,356 g/d, respectively) compared with prescribed-fed pigs (192 g/d and 974 g/d, respectively). Over the entire 15-d feeding study, average daily BW gain (234 g/d), average daily feed intake (1,140 g/d) and milk intake-to-BW ratio (4.60) were greater (P < 0.05) in the ad libitum treatment compared with prescribed feeding (180 g/d, 830 g/d, and 3.81 respectively). Insulin concentrations were greater (P < 0.05) in the ad libitum treatment (348 µIU/mL) 30 min after feed provision compared with the prescribed treatment (190 µIU/mL). Video analysis of spatial preference within HC suggested pigs in the prescribed treatment spent more (P < 0.05) time in quadrant 4 during wk 1 (5.43% of time recorded) compared with the ad libitum treatment (3.82% of time recorded), likely due to quadrant 4 housing the feed bowl. However, all other time points had no effect on spatial preference. Overall, the type of feeding style altered growth performance and insulin concentrations within young pigs and may impact the spatial preference of pigs within their home-cage environment.
71 Growth and reproductive responses to gonadotropins in gilts fed on ad libitum (AD) or restricted (RS) bases using an electronic sow feeder (ESF)
Authors: Niblett Richard T , Williams Kimberly A , Cross Marguerite B , Clapp Alexis L , Estienne Mark J
Published: May 2024

Previous work in our laboratory showed that age at puberty was similar for replacement gilts fed on either RS or AD bases using an ESF. The objective of this investigation was to determine the effects of feeding (RS vs. AD) on growth and sexual development in gilts treated with gonadotropins (P.G. 600; Merck Animal Health, Rahway, NJ). Prepubertal crossbred gilts were moved at 150 d of age to an open pen with an ESF (ACCUTEAM, Osborne Industries, Osborne, KS) located in an environmentally controlled, curtain-sided building. A 10-d training period to the ESF ensued, during which all gilts received feed on AD basis. At 160 d of age, gilts were allocated to treatments in a 2-by-2 factorial design. Treatments were RS plus P.G. 600 (n = 9), RS without P.G. 600 (n = 10), AD plus P.G. 600 (n = 8), or AD without P.G. 600 (n = 8). The P.G. 600 treatment was administered at 170 d of age. Estrus detection commenced at d 171 and continued for 32 d. Puberty onset was not affected by feeding basis (P = 0.85), P.G. 600 (P = 0.56), or feeding basis x P.G. 600 (P = 0.25). Time in estrus and body weight (BW) at puberty were also similar between treatments. Estrous cycle length was shorter (P < 0.01, 20.0 vs. 21.2 d, SE = 0.54) for RS compared with AD gilts. Bodyweights throughout the trial were similar between treatments but were affected by day (P < 0.01), typical of growing gilts. Feed disappearance was affected by feeding basis (P < 0.01, 2.30 vs. 4.54 kg/d, SE = 0.03 for RS and AD, respectively) and day (P < 0.01). For pubertal gilts, gain to feed ratio was improved (P < 0.01, 0.29 vs. 0.21, SE = 0.03) in RS compared with AD gilts, but average daily gain (ADG) was greater in AD gilts (P = 0.05, 0.75 vs 0.88 kg/d, SE = 0.09). Data were normalized for the 20-d period before second estrus. Feed disappearance was affected by feeding basis x day, and decreased in AD, but not RS gilts, as gilts approached estrus (P = 0.04). Feeding visits (P < 0.01) and feeding visit duration (P < 0.01) were affected by feeding basis with AD gilts consuming feed more frequently and spending less time eating per visit. In this study, RS feeding did not delay, and P.G. 600 did not hasten puberty onset. Moreover, RS gilts grew slower but were more feed efficient than AD gilts. We continue to find that employment of an ESF may support current estrus detection methods by monitoring feeding behavior in AD-fed gilts.
78 Estimates of genetic parameters for weight, wool, and carcass traits of Rambouillet sheep
Authors: Gunes Hilal Yazar , Brito Luiz F F , Murphy Tom W , Wilson Carrie S S , Lewis Ronald M
Published: May 2024

The Rambouillet sheep breed is the foundation to most western range sheep in the U.S. Through the National Sheep Improvement Program (NSIP), Rambouillet breeders seek to improve economically relevant traits. However, the parameters used in the NSIP genetic evaluation were last estimated two decades ago. Our aim was to re-estimate genetic parameters for body weight (BW), carcass, and wool traits. Data were provided by NSIP, which included BW at birth (BWT; n = 28,817), weaning [WWT; n = 5,633; age: 68 (SD 16) day], early post-weaning [PWTE; n = 23,303; 128 (SD 22) d], late post-weaning [PWTL; n = 7,689; 201 (SD 45) d] and as yearlings [YWT; n = 5,830; 375 (SD 33) d]. Yearling ultrasound scans of 12th rib backfat depth (YCF; n = 2,447) and eye muscle depth (YEMD; n = 2,457) were also available. Yearling wool traits were fiber curvature (YFC; n = 6,009), fiber diameter (YFD; n = 9,880), fiber diameter coefficient of variation (YFDCV; n = 8,803), greasy fleece weight (YGFW; n = 11,859) and staple length (YSL; n = 11,270). The pedigree consisted of 36,297 individuals. Animals with phenotypic records were progeny of 333 sires and 1,727 dams. A succession of univariate animal models was fitted. The most comprehensive model included direct and maternal additive genetic effects, their genetic covariance, and maternal permanent environmental and residual effects. Phenotypes were pre-adjusted for birth-rearing type category and, as covariates, dam age and age at recording. Contemporary group—a concatenation of flock, year, season, management group, sex, and, excluding BWT, recording date—was the only fixed effect fitted in the model. Model selection was based on the log-likelihood ratio test, and Akaike and Bayesian information criteria. The data structure, namely dams and their daughters and granddaughters contributing data, allowed reliable testing of the maternal effect terms. The direct-maternal genetic covariance did not explain variation for any trait (P > 0.18). The most parsimonious model for BW traits included direct and maternal additive genetic, and maternal permanent environmental, effects. For carcass and wool traits, only direct additive genetic effects were included in the final model. Such was unsurprising, as maternal effects often diminish as animals age. For the final models fitted (Table 1), direct heritabilities (± SE) for body weights ranged from 0.14 ± 0.01 (BWT) to 0.38 ± 0.04 (PWTL); the maternal heritabilities ranged from 0.04 ± 0.02 (PWTL; YWT) to 0.13 ± 0.01 (BWT). For carcass traits, direct heritabilities were 0.13 ± 0.04 (YCF) and 0.31 ± 0.05 (YEMD). For wool traits, they ranged from 0.37 ± 0.02 (YSL) to 0.58 ± 0.02 (YFD). These re-estimated parameter values are consistent with those used by NSIP, with the exception of PWTL (greater) and YSL (lower). With genomic data accumulating in Rambouillet, further refinements in parameter estimation are planned.
64 Effect of feeding intact protein from soybean meal instead of crystalline amino acids on growth performance, protein synthesis, and immune response of growing pigs
Authors: Cristobal Minoy , Lee Su A , Mallea Andrea P , Torres-Mendoza Leidy J , Acosta Jessica P , Parsons Carl M M , Stein Hans H
Published: May 2024

The objective was to test the hypothesis that feeding intact protein from soybean meal (SBM) instead of crystalline amino acids (AA) does not affect growth performance, protein synthesis, intestinal morphology, or immune response of growing pigs. A control corn-SBM diet was used. Three additional diets were formulated by reducing the inclusion rate of SBM and adding 3, 4, or 5 crystalline AA (i.e., Lys, Met, Thr, Trp, Val) to the diets, which resulted in reducing the protein concentration from 20.0% to 13.4%. All diets were formulated to meet requirements for standardized ileal digestible indispensable AA. A total of 176 pigs [initial body weight (BW) = 32.2 kg; SD = 4.2] were used. On d 1, 16 randomly chosen pigs were euthanized and body nutrient composition was determined. The remaining 160 pigs were allotted to the 4 diets using a randomized complete block design with 4 pigs per pen and 10 replicate pens per diet. Starting BW was the blocking factor. Individual pig BW and feed consumption were recorded. On d 28, one pig per pen was slaughtered and blood, carcass, and viscera were collected and analyzed for N, fat, and energy to calculate deposition in the body. Ileal mucosa, ileum and colon tissue and digesta were analyzed for blood characteristics, cytokines, tissue morphology, ammonia, and gene expression. Contrasts coefficients were used to determine linear and quadratic effects of reducing dietary protein. Results indicated that average daily gain, average daily feed intake, gain to feed ratio, carcass characteristics, and protein, lipid, and energy depositions were not affected by reducing SBM and increasing crystalline AA in diets (Table 1). However, energy efficiency tended to decrease (quadratic, P = 0.083) by reducing dietary protein. Blood urea N was reduced (linear, P < 0.001) as dietary protein was reduced, but blood total protein was not affected by dietary treatment. Cytokines, ileal and jejunal morphologies, and gene abundance of AA transporters in the ileal mucosa were not affected by dietary protein. Ammonia concentrations in ileal digesta increased and then decreased (quadratic, P = 0.043) and colon digesta tended to increase and then decrease (quadratic, P = 0.074) as dietary protein was reduced. Bacteria protein in colon digesta was reduced (linear, P = 0.030) by reducing dietary protein. In conclusion, providing AA from intact protein from SBM or from crystalline AA did not affect growth performance, intestinal morphology, and immune response of pigs. However, SBM in diets can provide energy that may be utilized more efficiently than energy from diets with less SBM and crystalline AA. Further research is suggested to elucidate if SBM improves utilization of other nutrients in diets for pigs.
72 Effect of In-feed fecal microbiota transplant on growth performance and gut microbiota dynamics of piglet subjected to post-weaning stress
Authors: Oladele Paul O , Richert Brian T , Johnson Timothy A
Published: May 2024

Weaning is one of the most stressful events for piglets, due to diet change from sow milk to grain-based feed. This diet change causes turnover of the gut microbial which can allow proliferation of pathogens leading to diarrhea. Antibiotics are administered to treat or prevent post-weaning diarrhea (PWD). Increased occurrence of antimicrobial resistance has increased incentives to develop viable antibiotic alternatives. PWD is most often caused by enterotoxigenic Escherichia coli. Similarly, in humans, severe diarrhea can be caused by Clostridium difficile colonization. Use of fecal microbiota transplants (FMT) has been shown to resolve C. difficile-induced diarrhea in 80 to 90% of human cases which may suggest FMT as a potential therapeutic option for post weaning diarrhea. We previously have shown that in feed fecal microbiota transplant (FMT) improved body weight (BW) gain in newly weaned piglets but it is not clear if this benefit will be replicated in piglets subjected to weaning stress. We hypothesize that FMT (in-feed) will increase colonization efficiency, improve growth performance and reduce diarrhea incidence compared with control in piglets subjected to post weaning stress. The objective of this study was to determine the effect of In-feed FMT of diarrhea index, growth performance and gut microbiota dynamics. Piglets (n = 240) subjected to physiological and transport weaning stress were allotted to 5 treatments: In-feed FMT (FMT1), doubles dose of In-feed FMT1 (FMT2), Oral gavage (FMT3), Antibiotic (positive control), and no supplementation (negative control). The donor material was screened for enterotoxigenic E. coli (F18 and F4). FMT was carried out for 14 d. Diarrhea index was observed for the first 14 d and animal BW, and fecal microbiota was collected by rectal swab on d 0, 3, 5, 7, 14, 21, 28 and 32 for analysis of microbiota composition. DNA was extracted from fecal samples and 16S rRNA gene libraries (V4 region) were prepared for bacterial community analysis. Data were analyzed with one-way ANOVA in R. Only positive control had significantly decrease in diarrhea index and significant increase BW gain on d 14, 21, and 28 (P < 0.05) but there was no effect of FMT (P > 0.05). In conclusion, antibiotics but not FMT was efficient in alleviating the negative performance effect in piglets subjected to post-weaning stress.
62 Implications of factor analyses and Bayesian network learning to develop composite traits of size attributes in developing beef heifers
Authors: Anas Muhammad , Zhao Bin , Dahlen Carl R , Swanson Kendall C , Ringwall Kris A A , Hanna Lauren L L Hulsman
Published: May 2024

Advancements in phenotypic data collection methods provide opportunities to capture complex biological traits more efficiently. Even so, interpreting those phenotypes and using them in selection decisions is challenging in beef cattle production. Objectives of this study were to 1) develop composite phenotype(s) of economic importance in beef heifers given attributes of their body conformation and ultrasound-based measures of reproductive and carcass traits, and 2) identify associated genomic regions under selection using the structure equation modeling (SEM) approach. In this study, we hypothesized that the interplay of factor analysis and Bayesian Network Learning (BNL) approaches would better define the complex composite traits for size and carcass-related traits in beef heifers. Phenotypic data of admixed beef heifers (n = 336) for different reproductive, body conformational, and carcass-associated phenotypic traits (n = 16) were collected. Using exploratory and confirmatory factor analyses, two latent variables explaining 14 phenotypic traits were identified, herein called Body Size (BS; n = 7 traits represented) and Body Composition (BC; n = 7 traits represented). To efficiently model them in genome-wide association studies (GWAS), fixed effects of data collection year, dam age, and primary breed group as well as causal network structure identified through BNL were used within SEM model of GWAS. Body Size was directly or indirectly contributing to BC based on BNL structure. Given the data-driven approach and novelty of the data, BayesCπ model was applied with the sliding window of 1 Mb to avoid noise and linkage disequilibrium implications. Regions capturing large amounts of genetic variance (Posterior Probability of Association, PPA ≥ 0.8) were mapped to their closest gene for enrichment analysis. Twenty-four different genes were identified associated with both composite phenotypes. Functional enrichment analysis of significantly involved pathways (FDR < 0.05) indicated that genes from the HERC family (HERC3, HERC6, and HERC5) were found involved in cellular growth, and those from desmosomes (DC2, and DC3) were involved in morphogenesis like BS. Genes related to energy metabolism like IMPAD1, and PIGY, along with genes associated with traits like muscular development, and other carcass traits (i.e., FAM184B, NCAPG, and LCORL), were also found associated with BS and BC. Heritability ranged from 0.551 ± 0.048 to 0.897 ± 0.145 for BS and BC, respectively. The combined heritability of reproductive and carcass traits (BC) was much greater than the heritability of any related individual trait reported to date and was comparable for individual BS-related traits. Given this, we conclude that the implications of factor analyses with BNL can provide better biological insights for improved genomic selection in beef cattle, even for traits of low heritability.
132 Carcass merit, primal cutout, and retail yield of Holstein and Holstein x SimAngus finished calves
Authors: Schnurbusch Teagan , Callahan Zachary D , Petry Amy L , Wiegand Bryon R
Published: May 2024

Dairy-beef has increased in popularity, altering the U.S fed beef supply. The objective of this study was to evaluate the effect of Holstein x SimAngus breeding on carcass composition, carcass performance, and primal cutout. Calves were sourced (n = 10 Holstein steers, n = 13 Holstein x SimAngus (Hol x SimAngus) steers and n = 12 Hol x SimAngus heifers) from University of Missouri Foremost Dairy. At 190 kg calves were randomly assigned to one of two treatments, Fast = fed to achieve 1.13 kg gain/d or Slow = fed to achieve 0.57 kg gain/d. Calves were individually fed for 147 d, then moved to group feedlot housing. Cattle were humanely slaughtered under USDA inspection, immediately following slaughter hot carcass weight (HCW) was recorded. Following slaughter, carcass length, body width, backfat thickness and area of the longissimus muscle (LM) was recorded. One side of the carcass was fabricated to various cuts following the Institutional Meat Purchasing Specifications. Round were knife separated into fat, bone, and lean. Area of the LM was measured for the entirety of the Ribeye Roll and Strip Loin in 2.54 cm sections. Warner Bratzler Shear Force (WBSF) and Slice Shear Force (SSF) tests were analyzed on strip steaks. Data were analyzed as a linear mixed model as a 2 by 2 + 1 factorial design with the fixed effect factors of breed and diet nested relative to Holstein steers using PROC MIXED of SAS 9.4 (SAS Institute, Cary, NC). The Satterthwaite method for degrees of freedom was used to analyze data under the assumption of unequal variance between treatments. Significance was denoted at P ≤ 0.05. Treatment diet did not impact carcass composition or fresh meat parameters (P >0.05). Hol x SimAngus carcasses exhibited shorter carcass length (P < 0.01) and body lengths (P = 0.002) compared with Holstein carcasses. Body width was narrower for Hol x SimAngus carcasses (P < 0.01). Hol x SimAngus carcasses had heavier hot carcass weights compared with Holstein carcasses (P = 0.0159). Dressing percentage was greater for Hol x SimAngus carcasses (P = 0.0001). Holstein carcasses had less backfat (P = 0.0003). LM area was larger for Hol x SimAngus carcasses (P < 0.01). Hol x SimAngus carcasses had heavier Rib, Full Loin and Round primals (P < 0.05). Ribeye Roll and Strip Loin weight was heavier in Hol x SimAngus carcasses (P < 0.01). Holstein carcasses displayed heavier round (P = 0.0002), directly related to an increase in bone weight of the round (P < 0.01) No differences were observed for WBSF (P = 0.427) or SSF (P = 0.264). Hol x SimAngus LM area for all sections of the Ribeye Roll and Strip Loin were larger than Holsteins (P < 0.05). Carcass composition, primal cutouts, and retail yield suggest that Holstein x SimAngus carcasses had improved yield production compared with Holsteins without a loss in quality.
134 Does inclusion of high oleic soybeans in a swine finishing ration influence lipid oxidation and consumer taste panel preference?
Authors: Castellanos Natalie Acosta , Maddock Robert , Thaler Robert C , Young Jennifer M , Mueller Shane , Koch Kim , Berg Eric P
Published: May 2024

The objective of this study was to determine if a swine finishing ration that included soybeans with greater concentration of oleic acid will have an impact on lipid oxidation and palatability of pork. Crossbred pigs [n = 72; initial body weight (BW) = 78 ± 9 kg] were blocked by BW, sex, and distributed within 18 pens. Each pen was randomly assigned to 1 of 3 experimental diets: a control soybean-meal (CTRL), extruded conventional soybean (CONV), and extruded high oleic acid soybean (TRU). Six different harvest groups (n = 12/group) were created across treatments to ensure uniformity of final BW. Therefore, experimental diets were offered to animals for 34, 37, 41, 42, 48, or 50 d, until all pigs reached 118 ± 5 kg. Carcasses were harvested, and chilled (2°C) for 24 h, before fabricating one 2.5 cm chop from the 11th rib of the right carcass side. The chops were vacuum packaged, aged for 7 d at 2 oC, and frozen (-18 oC) for later sensory analysis. Pork chops were thawed and cooked to 71 oC peak internal temperature (AMSA sensory guidelines) and fed to 115 consumers that rated overall liking, flavor, tenderness, juiciness, and presence of off flavors using hedonic scales. Also, a 50 g sample was obtained from each loin at the 12th rib, aged for 7 d and frozen at -80 oC for evaluation of malondialdehyde (MDA) as indicator of lipid oxidation. Subcutaneous fat samples were obtained from the first thoracic vertebra, frozen, and saved for fatty acid analysis. Data were analyzed using the MIXED procedure of SAS where diet was the main effect, while pen and breed were random effects. Repeated measures were used to analyze the consumer panel. Differences were considered significant at P ≤ 0.05 with pen as experimental unit. There were no significant differences (P > 0.05) for consumer perception of overall like, pork flavor, and presence of off flavors. Experimental diets impacted the perception of juiciness and tenderness (P < 0.05), where CONV was perceived as juicier and more tender than CTRL and TRU. As expected, diet affected the fatty acid profile of subcutaneous fat (P < 0.0001), with TRU having the greatest percentage for oleic (43.9 %), CONV the greatest percentage for linoleic and linolenic (17.8 and 1.3 % respectively), and CTRL for saturated fatty acids (34.5 %). Surprisingly, the lipid oxidation was not affected by the diet (P > 0.05). These results indicate that feeding extruded high oleic soybeans during the finishing period can modify the fatty acid profile in pork by improving the percentage of unsaturated fatty acids, so these soybeans can be considered as an alternative to improve nutritional value of pork without increasing the lipid oxidation or affecting the consumers acceptability.
127 Utilizing predictive models for bone mineral content and bone mineral density as a tool to assess dietary phosphorous
Authors: Taylor William E , Crome Thomas A , McKibben Grace C , Ross Jason W , Lonergan Steven M , Steibel Juan P , Gabler Nicholas K
Published: May 2024

Dietary phosphorous is a necessary nutrient for bone development in pigs at all stages of its growing. Deficiencies in phosphorous decrease bone mineral content (BMC) and bone mineral density (BMD) and may be a causative of lameness. However, the normal range expected in whole body (WB) and individual bones for BMC and BMD in commercial pigs has been poorly defined. Therefore, our objectives were to 1) model normal WB bone density at multiple timepoints in wean to finish pigs, and 2) determine the extent to which individual bone (femur and 3rd metatarsal) BMC and BMD could predict WB BMC and BMD. Mixed sex pigs [Camborough (1050) x 337, PIC] were utilized and included freshly weaned ~21 d (n = 8), ~44 d of age (n = 24), ~84 d of age (n = 24) and ~154 d of age (n = 24). Pigs were individually penned. Excluding weaning age, at each age group pigs were randomly assigned to diets adequate, marginally deficient, or deficient in available phosphorus (avP) and fed for 3, 4, and 6 wk (age group 44, 84, 154, respectively). Within each age group, diets were formulated to meet nutrient and energy requirements except for avP and pigs fed ad libitum. On-test and off-test body weight (BW) and feed intake and gain to feed ratio were assessed for each age group. At the end of each feeding period, all pigs were euthanized and WB, femur (F) and 3rd metatarsal (M) BMC and BMD determined by dual X-ray absorptiometry (DXA). Data were analyzed using linear and generalized additive models that predicted response variables (BMC or BMD) as a function of BW or age. Only pigs fed adequate avP diets were used in the model fit. Pigs fed adequate avP diets increased BMD with age (0.22, 0.42, 0.84 and 1.10 g/cm2, days of age 21, 44, 84 and 154 respectively, P < 0.001). Within day of age 84, marginally and deficient avP diets reduced BMC and BMD by 21 to 41% (P = 0.002) and 12 to 25% (P = 0.006), respectively. Within day of age 154, marginally and deficient avP diets reduced BMC and BMD by 9% (P = 0.05) and 6 to 8% (P = 0.06), respectively. Body weight record and individual bone (F and M) BMC and BMD from pigs fed deficient avP diets were used to predict WB BMC and BMD and the mean square error of prediction was selected as a criterion to evaluate the ability of the models to detect these inadequately fed pigs. Using the selected models, pigs fed nutritionally deficient diets were detected due to 2- to 7-fold increase in MSE of predicted WBMD or WBMC compared with pigs fed adequate diets. These models can be used to assess bone development and strength in growing pigs and to infer the adequacy of avP level supplied in their diets.
126 A nutritional solution based on calcidiol (25-OH-D3, HyD) and triterpenoid affects muscle protein synthesis pathways in grower-finisher pigs
Authors: Payling Laura , Romero Luis F , McCormack Ursula M M , Walsh Maria C , Roger Laurent , Calvo Estefania Perez
Published: May 2024

To boost profitability in pig production, it is important to achieve increased lean growth rates and maximize efficiency, especially in grower-finisher pigs where feed intakes are high. Molecular research, especially the study of gene expression, is a proven tool for understanding the precise mechanisms behind muscle tissue growth, including a recent focus on pathways such as the mammalian target of rapamycin (mTOR). In the current work, gene expression analyses were used to study the mode of action of the combination of calcidiol (25-OH-D3, HyD) and triterpenoid, which has shown significant growth and efficiency improvements in grower-finisher pigs (McCormack et al., 2024). Three experimental diets were evaluated for 7 wk; Positive control: 0.7% total Ca, 0.36% total P, vit D3 at 1500IU/kg feed (PC), negative control: PC diet + 30% reduced Ca and 10% reduced P (NC), and NC diet with 1,500IU D3 in calcidiol form (25-OH-D3, HyD) and triterpenoid (NC+). At 19 wk of age, 16 animals per treatment were sacrificed and tissue samples were taken from the longissimus muscle and preserved in RNA later solution. The RNA was extracted, quality control checked, and mRNA sequenced using the Illumina platform with 150 base pair paired-end sequencing and 30M read depth. The sequenced data were aligned to the Sus scrofa reference genome (Sscrofa11.1) using Kallisto. Data were normalized and analyzed for differentially expressed genes (DEGs) between treatments using DeSeq2. Genes were assigned to biological pathways using Biofractal’s customisation of the Reactome pathway database. For statistical analysis, RNA integrity number and treatment were included in the model. In the PC compared with the NC, there were 71 DEGs using a false discovery rate (FDR) of < 0.10. Altered pathways included the inhibition of cellular stress pathways and increased cell turnover in the muscle of PC compared with NC pigs. In the NC+ compared with the NC, there were 155 DEGs (FDR < 0.10). The most significantly upregulated gene in the NC+ treatment was adenylate cyclase (FDR < 0.001), an upstream regulator of several pathways related to energy metabolism and muscle protein synthesis. This mechanism was confirmed in the pathway analysis, which found that the NC+ treatment activated PKA-mediated phosphorylation of CREB, a pathway that inhibits muscle atrophy. Furthermore, the NC+ treatment activated several pathways related to muscle growth, including the mammalian target of rapamycin complex 1 (mTORC1). In this study the addition of calcidiol (25-OH-D3, HyD) and triterpenoid to the diet was found to specifically affect molecular pathways in the muscle of grower-finisher pigs involved in both the inhibition of muscle breakdown as well as activating muscle growth.
131 DNA methylation profile in bovine fetal liver is affected by maternal vitamin and mineral supplementation during early gestation
Authors: Anas Muhammad , Ward Alison K , McCarthy Kacie L , Borowicz Pawel P P , Reynold Lawrence P P , Caton Joel S , Dahlen Carl R , Diniz Wellison J j S
Published: May 2024

Early gestation is the critical period for successful pregnancy establishment. During this period, maternal nutrition affects fetal development with potentially long-lasting consequences on offspring performance. Despite the known effects of vitamins and minerals on embryonic development, supplementation is still not a widely adopted practice. Here we focused on the effects of maternal vitamin and mineral supplementation from pre-breeding to d 83 of gestation. We hypothesized that the DNA methylation pattern of genes involved with fetal hepatic metabolism and function would be altered in response to vitamin and mineral supplementation during early gestation. Sixteen Angus crossbred heifers (~16 mo of age) were randomly assigned to either a treatment (vitamin and mineral supplementation, VTM, n = 8) or control (corn-based carrier without supplementation, NoVTM, n = 8) group. Supplemented heifers received 0.45 kg •heifer-1•d-1 of to provide 113 g of vitamin-mineral premix (Purina Wind & Rain Storm All-Season 7.5 Complete, Land O’Lakes, Inc., Arden Hills, MN) from d 71 to 148 before breeding to d 83 of gestation. All heifers received 100% of NRC recommended nutritional requirements targeting 0.28 kg •heifer-1•d-1 of gain. The heifers were bred through artificial insemination following a 7-d Co-Synch + CIDR estrus synchronization protocol. All pregnant heifers were surgically ovariohysterectomized on d 83, and liver samples were collected from the fetuses. DNA methylation profiles from 16 fetuses (8 per treatment) were determined using Reduced Representation Bisulfite Sequencing (RRBS). The analysis was conducted using methylKit pipeline where data was normalized using principal components. We identified 794 differentially methylated cytosines (DMCs) for the control (NoVTM) vs VTM comparison. Most of the DMCs were found in introns followed by intergenic, promoter, and exonic regions. Among these DMCs, 60% (479) were hypermethylated and 40% (315) were hypomethylated, potentially regulating 739 nearby genes (FDR < 0.1). Biological processes over-represented by these genes included transport of ions through voltage gated channels (KCNK13, KCNT1, CACNA1B, KCNK9, LRRC55, KCNAB2, CACNA1S, KCNJ2, CACNG5, CLIC5, TPCN2, KCNQ1), which may be associated to pregnancy establishment by inducing pregnancy-associated relaxation and uterine artery dilatation. Some genes associated with structural development were also regulated by VTM supplementation (i.e., TIAM1, COL18A1, DYSF, BMP10, RXRA, EHMT1, COL4A2, PLEC, ZFAT, MTMR2, NAV1, ANHX, ACACB, and LIMK2). Collectively, these results suggest that periconceptual maternal vitamin and mineral supplementation affects the methylation pattern and potentially regulates the expression of genes involved in fetal liver development and ion transport.