bluuebunny/crossref_metadata_2025 huggingface dataset:
294 The effects of titrated levels of water soluble zinc amino acid complex on immune response of nursery pigs
Authors: Aparachita Pornpim , Carter Scott , Sawyer Afton , Harshman Jared , Ward Terry , Rambo Zach
Published: December 2019

Previously, we reported that supplementing titrated levels of a water soluble zinc amino acid complex (ProPath®Zn LQ, Zinpro Corporation, Eden Prairie, MN) via water (0 to 80 mg/L) to nursery pigs resulted in a lower inflammatory response after LPS challenge. To evaluate the efficacy of higher titrated levels, 280 pigs (5.5 kg BW; 19-d old) were allotted randomly to water treatments: 0, 40, 80 and 160 mg Zn/L of water (7 pens/treatment; 10 pigs/pen). Pigs were fed corn-soybean meal based diets with added Zn as ZnO or Cu as CuSO4: Phase 1 (2,500 mg Zn/kg; d 1–7), Phase 2 (1,750 mg Zn/kg; d 7–14), Phase 3 (200 mg Cu/kg; d 14–23), and Phase 4 (200 mg Cu/kg; d 23–42). At d 23, pigs were challenged by i.m. injection of lipopolysaccharide (12 µg/kg BW). Blood, BW, and rectal temperature (RT) were obtained from two pigs per pen at h 0, 3, and 12 of the challenge. Increasing water zinc resulted in linear reductions in RT (P = 0.02) and serum TNF-α concentration (P = 0.05) at h 0 prior to LPS injection. Post-LPS injection, increasing water zinc decreased linearly RT at h 3 (P = 0.01) and serum Zn:Cu ratio at h 3 (P = 0.04) and 12 (P = 0.01), and decreased serum TNF-α concentration at all hours (quadratic, P < 0.05). Additionally, increasing water zinc tended (linear, P = 0.07) to attenuate the decrease in BW following LPS from h 0–12. However, there were no effects on serum and salivary CRP concentrations (P > 0.05) within 12 hours of LPS challenge. At d 42, salivary CRP concentration decreased (quadratic, P = 0.03) with increasing zinc. In conclusion, supplementing ProPath®Zn LQ via drinking water to nursery pigs mitigated the febrile response and decreased cytokine production during an acute immune challenge.
354 Dietary supplementation with fermented mixed feed improves growth performance and meat quality in finishing pigs
Authors: Hao Lihong , lu Zeqing
Published: December 2019

Two experiments were conducted to evaluate the effects of feeding fermented mixed feed (FMF) on performance, meat quality, muscle fatty acids profile and antioxidant ability in finishing pigs. In experiment 1, 225 finishing pigs were allocated into 3 dietary treatments. Pigs in 3 groups were fed a basic diet or basic diet supplemented with 4% and 8% of FMF. After 35 days of the experiment, growth performance was evaluated. In experiment 2, 600 pigs were distributed into 3 treatments, which were fed with a basic diet or basic diet supplemented with 5% and 10% of FMF. At the end of the experiment, 24 pigs were slaughtered for the determination. In experiment 1, feeding 8% FMF improved (P < 0.05) ADG and decreased (P < 0.05) F/G compared with CON. In experiment 2, compared with CON, dietary supplementation with 10% FMF decreased (P < 0.05) F/G. Moreover, the ADFI and ADG were tended to be higher in pigs fed the FMF diet. Feeding 10% FMF increased (P < 0.05) loin muscle area, a* value, marbling score, intramuscular fat (IMF), and inosine acid (IMP) and decreased (P < 0.05) drip loss and shear force of longissimus thoracis (LT) muscle. The percentages of C18:1ω-9c, C18:2ω-6c, and C20:4ω-6c in LT muscle were increased (P < 0.05) in pigs fed 10 % FMF diet. Furthermore, greater (P < 0.05) SOD and GSH-Px activities were observed in 10 % FMF group in serum and LT muscle of pigs. Collectively, the present study suggested that dietary FMF supplementation improved the growth performance, meat quality parameters, unsaturated fatty acids proportions, and antioxidant ability.
353 Starch to fat ratio in piglet nutrition
Authors: Adebowale Tolulope O , Yao Kang , Yin Yulong
Published: December 2019

Dietary high energy density (HED) and the energy compositions, especially the fat and starch composition could have a variable effect on performance, intestinal health and the profitability of piglet production. The present study evaluated the effects of dietary energy densities and digestible energy ratio of starch to fat on intestinal functions and growth performance of growing pigs. A total of 48 healthy weaners (9.60 ± 0.13 kg) were allocated to two dietary energy densities (14.21 and 15.91MJ/kg) and two digestible energy ratio: high starch: low fat, HSLF (9:1) or low starch: high fat ratio, LSHF (1:3) in a factorial arrangement. It was found that dietary LSHF ratio induced diarrhea in the weaner pigs (P < 0.001). The feed intake of weaners was increased by HED (P < 0.05), however, this did not result in improved body weight gain (P > 0.05). The HED reduced (P = 0.017) energy digestibility, while digestible energy ratio reduced crude protein digestibility and amino acid utilization in the weaners. Fat and dry matter digestibility were not significantly affected (P > 0.05). Dietary LSHF ratio increased intestinal villus height/crypt depth ratio in the duodenum and ileum (P < 0.05). The lymphocyte count was increased by HSLF energy ratio. The highest high-density lipoprotein concentration was exhibited in weaners fed dietary LSHF energy ratio (P < 0.01) and dietary HSLF ratio increased the duodenal sucrase and lactase activities (P < 0.01). The dietary LSHF ratio showed an increased tendency to increase fecal ammonia concentration, but dramatically decreased fecal short-chain fatty acid concentrations (P < 0.01). The HED seems to induced oxidative stress (P < 0.01). The study suggests that dietary high fat, but not dietary starch or HED could decrease the intestinal health of weaner pigs.
357 Bridging the gap between reality and genetic potential in pig performance by nutritional strategies
Authors: Chen Daiwen , Zheng Ping , che lianqiang , Yu Bing
Published: December 2019

The global pork output in 2018 reached over 100 million tons and will continue to grow. However, great gap still exists between current productivity and the full genetic potential of pigs. Our hypothesis was that current nutritional profile could not meet the pig biological requirement, and that modifying nutritional strategies can maximize their genetic potential. To test this hypothesis, three experiments were conducted using fluid feed, fermented feed, and modified nutrient profile, respectively. Experiment 1 utilized 360 DLY weaning piglets with 6 replicate pens per treatment and 30 pigs per pen. Piglets were fed either a solid feed or a fluid feed with the exact same formulation. Results showed that fluid feed significantly increased ADFI by 53% from 245 to 375 g/d and increased ADG by 54% from 183 to 281 g/d from d 23 to 30 (P < 0.001). Experiment 2 utilized DLY weaning piglets fed 3 dietary treatments: Corn-SBM control, control + 75 mg/kg chlorotetracycline, and 12h-fermented control diet with 6 replicate pens per treatment and 3 pigs per pen. Results showed that 12h fermentation significantly increased ADG from 374 to 474 g/d from 35–56 d, reduced FCR from 1.74 to 1.52, and reduced diarrhea occurrence from 24.4% to 6.6% compared to control (P < 0.015). Performance from the fermentation group was also significantly better than the chlorotetracycline group. Experiment 3 utilized 8 individually-housed PIC pigs fed modified nutrient profile to determine performance from 7 to 147 days of age. Results showed that BW reached 26.5, 33, 100, 112.6 kg on d 60, 70, 134, 147, respectively, and overall FCR was 1.93. Results from these experiments demonstrated that the genetic potential of pig can be realized in greater extend by nutritional strategies.
370 Dietary soluble fiber increases the intestinal butyrate-producing bacteria, reduces intestinal permeability, and improves metabolic syndrome in sows during perinatal period
Authors: Cheng Chuanshang , Wei Hongkui , Peng Jian
Published: December 2019

In humans, metabolic and immune changes during the perinatal period also describe metabolic syndrome. Gut microbiota can cause symptoms of metabolic syndrome in pregnant women. Gut microbiota modulations caused by pregnancy nutrition constitute an interesting target in the metabolic status of pregnant individual. However, studies investigating the changes of the metabolic characteristics and gut microbiota in sows throughout pregnancy and lactation are lacking, and the effects of soluble fiber diet during pregnancy on them are still underexplored. Sows were allocated to either control or 2.0% pregelatinized waxy maize starch plus guar gum (SF) dietary treatment during gestation. The metabolic characteristics, gut permeability and inflammation status, and gut microbiota composition and metabolism of sows during pregnancy and lactation were analysed. The plasma levels of hs-CRP and HOMA-IR values were increased in days 109 of gestation (G109) and days 3 of lactation (L3), while dietary SF reduced plasma hs-CRP concentrations and the HOMA-IR values. The levels of plasma zonulin and fecal endotoxin and lipocalin-2 were increased in G109 and L3, while dietary SF reduced elevation of plasma zonulin and endotoxin and fecal lipocalin-2. Next-generation sequencing analysis revealed that dietary SF increased levels of butyrate-producing Ruminococcaceae, Lachnospiraceae, and Oscillospira. The fecal and plasma levels of butyrate were also increased. Additionally, the increased relative abundances of Lachnospiraceae in SF sows negatively correlated with plasma hs-CRP and HOMA-IR while Oscillospira was negatively fecal lipocalin-2. Our data reveal that the sow exhibits a metabolic syndrome and dramatical changes in gut microbiota during perinatal period. Besides, dietary SF has beneficial effects on insulin sensitivity, intestinal permeability and inflammation maybe via increasing butyrate-producing bacteria and butyrate production.
141 A nutrigenomics approach using RNA sequencing technology to study nutrient-gene interactions in agricultural animals
Authors: Liao Shengfa F , Hasan Shamimul , Feugang Jean M
Published: December 2019

Animal life essentially is a set of gene expression processes. Thorough understanding of these processes driven by dietary nutrients and other environmental factors can be regarded as a bottom line of modern advanced animal nutrition research for improving animal growth, development, health, production, and reproduction performance. Nutrigenomics, a genome-wide approach using the knowledge and techniques obtained from the disciplines of genomics (including transcriptomics) and molecular biology, is to study the effects of dietary nutrients on cellular gene expression, cellular metabolic responses and, ultimately, the phenotypic changes of a living organism. Transcriptomics can be applied to investigate animal tissue transcriptome at a defined physiological or nutritional state, which provides a holistic view of the intracellular expression of RNA, especially mRNA. As a novel, promising transcriptomics approach, RNA sequencing (RNA-Seq) technology can monitor all-gene expressions simultaneously in response to dietary intervention. The principle and history of RNA-Seq technology will be briefly reviewed, and the three principal steps of this methodology, including the laboratory analysis of tissue samples, the bioinformatics analysis of the generated sequence data, and the subsequent biological interpretation of the data, will be described. The application of RNA-Seq technology in different areas of animal nutrition research, which include maternal nutrition, feeding strategy and gut microbiota, will be summarized. Lastly, the application of RNA-Seq technology in swine science and nutrition research will also be discussed. In short, to further improve animal feeding or production efficiency, RNA-Seq technology holds a great potential to be employed to explore the new insights into better understanding of nutrient-gene interactions in agricultural animals, and it is expected that the application of this cutting-edge technology in animal nutrition research will continue to grow in the foreseeable future. This research was supported in part by a USDA-NIFA Multistate Project (No. 1007691).
372 Dam body condition during lactation influences piglet growth and maturation pre-finishing
Authors: Rempel Lea A , Keel Brittney N , Oliver William T , James Wells , Lents Clay , Rohrer Gary A
Published: December 2019

We previously reported, piglets reared by fat sows, weighed less during lactation, but were heavier by 45 d of age in comparison to piglets reared by thin or moderate sows. The objective of the current study was to evaluate weight and body condition during pre-finishing and age at puberty of gilts in relation to body condition of their dams at weaning. Eight weekly farrowing seasons (parities 1–4, n = 157 litters) were used to evaluate sow body condition (weaning) and piglet growth. Sows were categorized as thin, moderate, or fat by last rib caliper measurement at weaning. Individual pig weights were recorded at approximately 100 and 145 d of age. Additionally at 145 d of age, 10th rib backfat and loin eye were measured on a subset (n = 567) of pigs and first estrus was monitored in gilts reserved for breeding selection (n = 176). Pigs reared by fat sows tended (P < 0.10) to be heavier at 145 d of age (90.6 ± 0.75 kg) when compared to pigs reared by thin or moderate sows (89.0 ± 1.48 kg and 88.5 ± 0.82 kg, respectively). Tenth rib backfat during finishing was not different in pigs reared by fat or thin sows (10.0 ± 0.09 mm and 9.8 ± 0.27 mm, respectively); and tended (P < 0.10) to be less in pigs reared by moderate sows (9.7 ± 0.09 mm) than in pigs from fat sows. Tenth rib loin eye area was similar. Gilts developed in litters from thin sows tended (P < 0.10) to have an early age at puberty in contrast to gilts from moderate or fat sows (182.5 ± 3.82 d vs 189.7 ± 2.49 d and 192.2 ± 1.94 d, respectively). Body condition of sows at weaning did not adversely affect pre-finishing pig growth, however pubertal development was improved in gilts from thin sows.
449 Late-Breaking: Impact of feeding a propriety yeast-based synbiotic product on fecal shedding of top-7 Shiga toxin-producing Escherichia coli in feedlot cattle
Authors: Amachawadi Raghavendra , Shi Xiaorong , George LeighAnn , Theurer Miles , Marston Twig , Holder Vaughn , Nagaraja T G
Published: December 2019

Shiga toxin-producing E. coli (STEC) belonging to serogroups O26, O45, O111, O103, O121, O145, and O157, called ‘top-7’, are major foodborne pathogens. Cattle are a major reservoir, in which STEC colonize the hindgut and are shed in the feces, which is a major source of contamination of food. Our objective was to evaluate the impact of a proprietary yeast-based synbiotic product (prebiotic and probiotic; Alltech, Inc., Nicholasville, KY) on fecal shedding of top-7 STEC in feedlot cattle. Twenty existing pens, housing 40–112 steers per pen, with an estimated 60 to 90 days to slaughter, were randomly assigned to a control group or a treatment group that received 22 g of the synbiotic product per steer per day, as a top dress, in a finishing diet. Twenty pen-floor fecal samples were collected from each pen on days 0, 21, 42, and 54. Fecal samples were enriched and subjected to a multiplex PCR assay targeting serogroup-specific genes for the top-7 STEC and three major virulence genes, stx1 (Shiga toxin 1), stx2 (Shiga toxin 2), and eae (intimin). Bivariate descriptive statistics for the major serogroups and virulence genes were assessed prior to multivariable analysis using mixed effects logistic regression. The overall prevalence of the top-7 serogroups were 44.5% of O26, 41.3% of O157, 15.1% of O103, 13.7% of O45, 7.8% of O121, and 0.6% of O111. The overall prevalence of stx1, stx2, and eae were 43.9%, 70.8%, and 49%, respectively. E. coli O26, O157, and O45 had a significant treatment and sampling day interaction (P < 0.0001). On d 42, fecal samples from treated group had lower prevalence (P < 0.01) of O26, O103, and O45 compared to the control group. In conclusion, the in-feed administration of the synbiotic product appears to reduce fecal shedding of certain top-7 STEC serogroups in the feedlot cattle.
381 Investigation of heat stress on differential gene expression in tolerant and susceptible pigs
Authors: He Yuqing , Maltecca Christian , Tiezzi Francesco , Flowers Billy
Published: December 2019

Heat stress adversely affects pig growth and reproduction performance by reducing feed intake, body weight gain, farrowing rate, and litter size. Heat tolerance is an important trait in pigs, allowing them to mitigate the negative effects of heat stress on their physiological activities. Yet, genetic variation and signaling pathways associated with the biological processes of pigs tolerant to heat stress are currently not fully understood. This study aimed at identifying differentially expressed (DE) mRNAs of pigs under different heat-stress environments using whole transcriptomic RNA-seq analyses. RNA was isolated from blood samples of boars (n = 12) collected at two time points (late winter and middle summer) and labeled as pre-stress when subjected to no heat-stress, and stress when subjected to heat stress for 2 months. Semen parameters, including sperm count, motility, normal morphology, droplets, and rejected ejaculate rate, were measured for boar classification into either tolerant or susceptible to the heat stress. Genes displayed different expression levels between susceptible and tolerant pigs under pre-stress, and stress period respectively. A total of 692 DE genes (654 down-regulated, 38 up-regulated) were found in susceptible pigs compared to tolerant pigs during the pre-stress period. A total of 724 DE genes (622 down-regulated, 62 up-regulated) were found in susceptible pigs compared to tolerant pigs during the heat stress period. Heat stress showed greater effects in significant transcript expression (FDR < 0.05) among susceptible pigs than tolerant pigs with 88 DE genes (51 down-regulated, 37 up-regulated) and 5 DE genes (1 down-regulated, 4 up-regulated), respectively. This study contributed to the expression profiles of transcripts and the exploration of novel genes in pigs responding to heat stress.
144 A modeling framework to assess the impact of the texas beef cattle water footprint on livestock sustainability
Authors: Menendez Hector M , Turner Benjamin L , Tedeschi Luis O
Published: December 2019

Anticipated growth in the demand for beef products driven by increased protein consumption, brings into question the efficiency, sustainability, profitability, and social dimensions of water use for U.S. beef production. Current assessment of U.S. beef production provides a wide range (695 to 14,191 L H2O/kg) of water footprint (WF) measurements of green (rainfed), blue (ground or surface), and grey (waste treatment) water use, but lacks defined region-specific estimates. The objective of this ongoing study is to develop a dynamic mathematical model for Texas beef cattle WF (TXWFB) that allows users to estimate a Texas WF, evaluate assumptions and parameters of current WF methodologies, identify water-use inefficiencies, and provide policy recommendations for a sustainable WF. The TXWFB was developed using Vensim DSS™ and evaluated with the Model Evaluation System™. The TXWFB model correctly replicated the previously published Chapagain and Hoekstra (2003; CH2003) water footprint results for beef cattle with a 36-month lifespan in both grazing [11,915 m3/t (0.4 t)] and industrial beef cattle [9636 m3/t (0.545 t)] systems. Then, parameters (diet composition and water footprints) from the CH2003 model were used as inputs into the TXWFB model to develop baseline scenarios for Texas, using ten climate regions (36-month lifespan; baseline grazing µ = 26,389 m3/t and industrial µ = 24,615 m3/t). The baseline results were then compared to grazing and industrial scenarios with regionalized Texas parameters for pasture, forage, and crop production (evapotranspiration, drought), diet/phase/region (cow-calf, stocker, and feedlot; 24 months). The TXWFB predictions for regional grazing (µ = 7,591 m3/t) and industrial (µ = 5,948 m3/t) results were 71 to 75% less than the baseline scenarios (P < 0.05). We concluded that the TXWFB estimates were considerably smaller than those previously published, suggesting that current WF methodologies can be refined to more adequately assess beef cattle WF in the US.
153 Creation of a feed composition database: Machine learning techniques for automated classification of corn grain products, preliminary results
Authors: Schlageter-Tello Andres A , Miller Phil S
Published: December 2019

Feed composition tables are a commonly used to develop research projects and to develop animal diets. Currently, the National Animal Nutrition Program aims to create a living database containing feed composition information using large datasets provided by commercial laboratories. Using large datasets should ensure representative nutritional values for feeds included in the database; however, managing large datasets requires computer codes to manage and classify feeds correctly. Thus, the objective of this project was to develop 2 models based on supervised machine learning techniques for automated classification of corn grain product samples. The database used in the study contained 88,057 samples of corn grain products resulting from the screening procedure previously described by Tran et al (2016). Two types of supervised machine learning models were developed: decision tree and random forest. Parameters included for feed classification were: dry matter, crude protein, neutral detergent fiber, ash, fat, and starch. Models were trained and validated using 70 and 30% of the dataset, respectively. The decision tree and random forest correctly classified 98.3 and 98.8% of validation dataset, respectively. For each corn grain product the performance of the decision tree and random forest were: corn germ = 91 and 91%; corn germ meal = 97 and 95%; corn gluten feed, dry = 99 and 100%; corn gluten feed, wet = 100 and 100%; corn gluten meal = 99 and 100%; corn grain, dry = 99 and 99%; corn grain, high moisture = 100 and 100%; corn grain, steam-flaked = 34 and 53%; corn hominy feed = 83 and 88%; and corn screenings = 44 and 60%, respectively. In conclusion, the random forest was superior to the decision tree approach for classifying corn grain products. Further development is required to improve the performance of models for classifying corn grain steam-flaked and corn screenings
150 Administering an appeasing substance to Bos indicus-influenced beef cattle at weaning and feedlot entry
Authors: Millican Allison , Cooke Reinaldo F , Brandão Alice , Schumaher Thiago , Souza Osvaldo , Castro Thais , Cappellozza Bruno
Published: December 2019

Bovine appeasing substance (BAS) is expected to have calming effect in cattle experiencing stressful situations, including weaning and feedlot arrival. In Exp. 1, 186 Bos indicus-influenced calves (73 heifers, 133 bulls) were weaned at 211 ± 1 d of age (d 0). Upon weaning, calves were ranked by sex and body weight (BW), and assigned to receive BAS (Nutricorp, Araras, SP, Brazil; n = 94) or water (CON; n = 92). Treatments (5-mL) were topically applied to the forehead of each animal. Calf BW was recorded and samples of blood and tail-switch hair collected on d 0, 15, and 45. Calves that received BAS had greater (P < 0.01) average daily again (ADG) from d 0 to 15, and BW on d 15 compared with CON. Overall ADG and BW on d 45 were also greater (P < 0.05) in BAS vs. CON. Plasma concentrations of haptoglobin were less (P < 0.01) in BAS vs. CON cattle on d 15, whereas cortisol concentrations in plasma and tail-switch hair did not differ between treatments (P > 0.16). In Exp. 2, 140 B. indicus-influenced bulls (~27 mo of age) were transported from a cow-calf ranch to a commercial feedlot (d -1), and maintained on a single pasture for 24 h. On d 0, bulls were ranked by BW and assigned to receive BAS (n = 70) or CON (n = 70) as in Exp. 1. Bulls receiving BAS had greater (P = 0.04) ADG from d 0 to 15, but less (P < 0.01) ADG from d 15 to 45 compared to CON. No other treatment effects were detected (P > 0.18). Therefore, BAS administration to beef cattle at weaning or feedlot entry had immediate benefits to ADG, which were sustained for 45 d in weaned calves but not in feedlot cattle.
147 Changes in body temperature of lot-fed Bos taurus and Bos indicus steers during a heat wave
Authors: Sammes Stephanie L , Lees Angela M , Cawdell-Smith Judy A , Gaughan John B
Published: December 2019

Body temperature (BT) is a reliable method for evaluating the thermal status of cattle. The objective of this study was to evaluate the regulation of BT in B. indicus and B. taurus steers during a heat wave event. Thirty-five steers (466.30±10.2kg) of mixed genotypes (B. taurus, n = 18; B. indicus, n = 17) were used in a larger 100-d study. Cattle were housed in six un-shaded pens at a commercial feedlot. Body temperature data for this were obtained at 1 h intervals over a 3-d heat wave event using in situ abdominal data loggers. Data were analysed using a repeated measures model, using residual maximum likelihood estimation. The model included genotype (B. taurus; B. indicus) and animal ID as random effects and hour as a fixed effect. Mean maximum BT occurred at 1500 h for B. taurus (40.52±0.03ºC) and 0400 h for B. indicus (40.48±0.31ºC). The BT of B. indicus decreased between 0400 h and 0700 h, and then increased to 1100 h (+0.10±0.01ºC/h), before decreasing again. The BT of B. taurus decreased between 0500 h and 0600 h, and then slowly increased (+0.04±0.01ºC/h) to 1500 h. Mean minimum BT occurred at 2100 h for B. taurus (40.12±0.11ºC) and 0700 h for B. indicus (40.00±0.22ºC). B. taurus maintained lower BT (40.21±0.05ºC) between 1900 h and 2200 h compared to B. indicus (40.27±0.05ºC) which may be due to disrupted heat loss mechanisms during the day, highlighting the importance of night time cooling. In response to increasing heat load, BT in B. taurus had slower increases but retained heat for longer, whilst B. indicus BT responded by a series of rapid increases and decreases. Developing an understanding of the differences in BT regulation in B. indicus and B. taurus will allow for more effective heat load management strategies during heat waves to be established.
151 Use of an automated computer vision system to predict body weight and average daily gain in beef cattle in different phases of growth development
Authors: Cominotte Alexandre , Fernandes Arthur Francisco Araujo , Dorea João R R , Rosa Guilherme J M , Machado-Neto Otávio
Published: December 2019

Frequent measurements of body weight (BW) in livestock production systems are very important because they allow the assessment of growth development of animals. However, monitoring animal growth through traditional weighing scales is laborious and stressful for animals. Thus, the objectives of this study were to: 1) assess the predictive quality of an automated computer vision system used to predict BW and average daily gain (ADG) in beef cattle; and 2) compare different predictive approaches (Multiple Linear Regression: MLR, Least Absolute Shrinkage and Selection Operator: LASSO, Partial Least Squares: PLS, and Artificial Neutral Networks: ANN). A total of 234 images of Nellore beef cattle were collected during weaning, stocker and feedlot phase. Biometric body measurements from each animal were performed using 3D images captured with the Kinect® sensor, together with their respective BW acquired using an electronic scale. The biometric measurements were used as explanatory variables for each predictive model. Prediction quality was assessed using a leave-one-out cross-validation strategy. The ANN approach resulted on higher precision and accuracy for BW prediction compared to the other methods, with Root Mean Square Error of Prediction (RMSEP) and squared predictive correlation (r2) equal to: RMSEP = 8.6 kg and r2= 0.91 for weaning; RMSEP = 11.4 kg and r2= 0.79 for stocker, and RMSEP = 7.7 kg and r2= 0.92 for beginning of feedlot. The ANN was also superior for prediction of ADG for the weaning to stocker, weaning to beginning of feedlot, weaning to end of feedlot, stocker to beginning of feedlot and beginning to end of feedlot, with RMSEP: 0.02, 0.02, 0.03, 0.10 and 0.09 kg/d, and r2: 0.67, 0.85, 0.80, 0.51 and 0.82, respectively. Overall, results indicate that an automated computer vision system is a potential tool for real-time measurement of BW and ADG in beef cattle.
155 Impacts of post-weaning growth rate on reproductive development and maternal productivity of replacement beef heifers
Authors: Schubach Kelsey , Cooke Reinaldo F , Brandão Alice , Marques Rodrigo , Bohnert David
Published: December 2019

The objective of this study was to compare growth, reproductive development, and productivity as primiparous in replacement beef heifers receiving diets to yield low (LGAIN), medium (MGAIN), and high (HGAIN) growth rates from weaning until their first breeding season. Seventy-two Angus × Hereford heifers weaned at 7 months of age were managed as a single group on pasture, and individually received supplements to achieve the desired average daily gain (ADG) until breeding (d 183). Accordingly, ADG was greater (P < 0.01) in HGAIN vs. MGAIN and LGAIN (0.85, 0.65, and 0.40 kg/d, respectively), and greater (P < 0.01) in MGAIN vs. LGAIN heifers. Puberty attainment until the breeding season was also greater in HGAIN vs. MGAIN and LGAIN (87, 65, and 56% pubertal heifers, respectively), but similar (P = 0.35) between MGAIN vs. LGAIN heifers. No differences were detected for pregnancy and final calving rate between treatments (P > 0.22), whereas HGAIN and MGAIN heifers were heavier (P = 0.05) at calving compared with LGAIN. Approximately 45 days after calving, milk production was estimated via weight-suckle-weight and milk samples collected from a subset of 10 heifers/treatment. Milk yield was less (P < 0.05) in LGAIN vs. MGAIN and HGAIN (5.0, 6.3, and 6.2 kg/d, respectively), and similar (P = 0.72) between MGAIN and HGAIN heifers. Expression of GLUT1 and GLUT9 in milk fat cells tended to be less (P < 0.09) in LGAIN vs. MGAIN and HGAIN, and similar (P = 0.33) between MGAIN and HGAIN heifers. At weaning, HGAIN and MGAIN heifers had heavier (P < 0.05) calves compared with LGAIN heifers (220, 214, and 206 kg, respectively), despite similar (P = 0.52) calf weaning age among treatments. Therefore, exposing replacement heifers to HGAIN hastened their reproductive development, without impairing milk productivity and calf weaning weight as primiparous cows.
401 Effect of zinc source and ractopamine hydrochloride on the growth performance and carcass characteristics of steers fed in confinement to harvest
Authors: Wagner John , Nelson William T , Engle Terry , Spears Jerry , Heldt Jeff , Laudert Scott
Published: December 2019

Four hundred and thirty-two beef steers (346.3 ± 63.7 kg BW) were used to determine the effects of Zn source on feedlot cattle fed ractopamine hydrochloride. Cattle were blocked in groups of 54 by BW and housed in 48 pens containing 9 steers per pen. Pens within a weight block were randomly assigned to treatments in a 2 x 3 factorial arrangement, with factors being: 1) 0 or 30.1 mg of ractopamine HCl/kg DM fed during the final 29 days on feed; and 2) Zn source: 90 mg of supplemental Zn/kg DM from ZnSO4; Zn sulfate (67%) + Zn methionine (33%); and Zn from Zn hydroxychloride, fed through the entire feeding period. Cattle were fed a high concentrate finishing diet for 154 d and slaughtered at a commercial abattoir. Average daily gain, DMI, feed efficiency and carcass characteristics were determined after slaughter. Zinc source had no impact on live animal performance. Cattle fed ractopamine HCl had greater (P < 0.01) final BW, greater (P < 0.001) ADG, improved (P < 0.001) G:F, heavier (P < 0.01) HCW, and larger (P < 0.05) longissimus muscle compared to non-ractopamine supplemented steers. There was a Zn source by ractopamine interaction (P < 0.01) for dressing percentage. Cattle receiving ractopamine HCl with Zn hydroxychloride had a greater dressing percentage (P < 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Cattle receiving ractopamine HCl with Zn sulfate had a lesser dressing percentage (P < 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Additional Zn source by ractopamine HCl interactions were not significant. These data indicate that Zn source has minimal impacts on feedlot steer performance and carcass characteristics when supplemented to cattle receiving 0.0 or 30.1 mg of ractopamine HCl/kg DM.
408 Effect of monensin intake during a stocker phase and subsequent finishing phase on rumen bacterial diversity of beef steers
Authors: Weiss Caleb P , Beck Paul A , Richeson John T , Tomczak Dexter J , Chai Jianmin , Hess Tom , Hubbell Don , Zhao Jiangchao
Published: December 2019

Three monensin levels during a stocker phase (0, 800, 1600 g/ton fed in a free choice mineral) and two levels during finishing [0 (U) or 37.5 mg/kg diet DM (M)] were used to determine the effects of monensin supplementation during a stocker and subsequent finishing phase on rumen bacterial communities of beef steers. Thirty calves were fed pearl millet (Pennisetum glaucum) hay with soybean hull and corn gluten feed supplement (0.5% BW daily, AF basis) or grazed fall wheat pasture (Triticum aestivum) during a stocker phase and then transported 1,067 km to Canyon, TX, for finishing. Rumen fluid was collected on d 0, 28, and the end of the stocker phase (d 85). Samples were also obtained at feedlot d 0, 14, 28, 56, and immediately prior to a diet change to include a beta-adrenergic agonist and before shipping for harvest. Rumen microbiota were characterized by next generation sequencing the 16S v4 hypervariable region with the Illumina MiSeq platform. During the stocker phase, Prevotella and Bacteroidetes were the most dominant genus regardless of diet or treatment. Monensin decreased (P ≤ 0.01) alpha diversity (Shannon Index) for cattle consuming hay on d 28 of the stocker phase. In the feedlot, Prevotella, Lachnospiraceae, and Bacteroidetes were the most abundant genus. Steers that were previously on the 0 and 1600 treatments during the stocker phase and were fed monensin at the feedlot had decreased alpha diversity (P = 0.04) on feedlot d 14 compared to those that did not. Monensin at the feedlot tended to increase alpha diversity on d 28 for cattle previously on the 1600 treatment (P = 0.06), and on d 56 for cattle previously on the 0 treatment (P = 0.06). This experiment provides a better understanding of the effect of monensin on rumen bacterial communities throughout production.
413 Effect of chitosan inclusion and dietary crude protein level on rumen fermentation in beef heifers fed a total mixed ration
Authors: Kirwan Stuart , Boland Tommy , Serra Eleonora , Rajauria Gaurav , Pierce Karina
Published: December 2019

Chitosan (N-acetyl-D-glucosamine polymer) is a natural biopolymer, which is the second most abundant organic compound on earth, found in lower plants and some arthropods and crustaceans. Studies with ruminants have shown that supplementing with chitosan can alter ruminal fermentation, including higher propionate concentration and lower acetate to propionate ratio, improving the energy efficiency within the rumen though data on nitrogen metabolism is lacking. Therefore, the objective of this study was to evaluate the effects of chitosan with different dietary crude protein (CP) inclusion on rumen fermentation in beef heifers. Eight ruminally cannulated Belgian Blue x Holstein Friesian heifers (752 ± 52Kg BW) were allocated one of four dietary treatments in a 2 x 2 factorial Latin Square design (n = 8). Diets were offered as total mixed ration (TMR) consisting of grass silage plus concentrate. Diets were offered once daily ad libitum. Dietary treatments were as follows: high CP (16%) +/- chitosan (10g kg-1 DMI) supplementation (HP+) or (HP-) and low CP (12%) +/- chitosan supplementation (LP+) or (LP-). Experimental periods were 25d in duration (14 d dietary adaptation and 10 d sampling). Rumen fluid was collected via cannula every 2 h post feeding for analysis of ruminal pH, ammonia (NH3) and volatile fatty acids (VFA) over a 48-hour period. Data was analysed using Proc Mixed procedure in SAS. Significant differences were considered when P < 0.05. Dietary treatment had no effect on ruminal pH (P > 0.05). Chitosan supplementation had no effect on ruminal NH3 and VFA concentrations (P > 0.05), whereas, animals offered 16% CP had higher concentrations of ruminal NH3 (P < 0.001). In conclusion, supplementing a TMR diet fed to beef heifers with chitosan had no effect on rumen fermentation. However, reducing dietary CP concentration fed to beef animals resulted in lower rumen NH3 concentrations.
417 Citrus aurantium flavonoid extract modifies the gene expression in the rumen of genes related to inflammation and behavior in Holstein bulls fed high-concentrate diets
Authors: Paniagua Montserrat , Crespo Javier F , Aris Anna , Devant Maria
Published: December 2019

One hundred forty-four bulls (164.8 ± 5.91 kg BW and 135 ± 7.2 d of age) were randomly allocated to one of 8 pens and assigned to control (C) or Citrus aurantium (BF, 0.4 kg of Bioflavex® CA per ton of concentrate). Each pen had one drinker, one separate straw feeder, and one three-space feeder where mash concentrate rich in corn, barley, DDG and wheat was offered. Concentrate intake was recorded daily, and BW and animal behavior by visual scan fortnightly. Animals were slaughtered after 168 d of study (12 periods of 14 d), HCW and carcass quality were recorded. Rumen wall samples were collected from 18 animals per treatment to analyze the expression of 15 genes associated with inflammation and behavior. Data were analyzed with ANOVA. In the rumen, the expression of free fatty acid receptor 2 (stimulates PPY and serotonin secretion), pancreatic polypeptide receptor 1 (acts asNPY and PYY receptor), cholecystokinin receptor 4 (is a CCK and gastrin receptor), Toll-like receptor-4 (pattern recognition receptor), IL-25 (proinflammatory cytokine) and β-defensin1 (antimicrobial peptide) were greater (P < 0.05) in C compared with BF bulls (P < 0.05). Moreover, the expression of all bitter taste receptors (TAS2R, member 7, 16, 38 and 39) which are related with eating modulation and immune function were lesser (P < 0.05) expressed in BF compared with C bulls (P < 0.05). The supplementation with citrus flavonoids in these bulls fed high-concentrate diets tended (P < 0.10) to improve concentrate efficiency, reduced oral non-nutritive behaviors, agonistic interactions and sexual behaviors. The reduction on TAS2R expression is indicative of an inhibition of bitter taste receptor function by BF and the expression increase in the other genes could explain the changes observed on animal behavior within the gut-brain axis paradigm.
412 Supplementation of high-grain diet with brewers’ spent grain protein hydrolysates reduced protein degradability and methane production in Rusitec
Authors: Ran Tao , Abeynayake Ranithri , Saleem Atef , Zhang Xiuming , Shen YiZhao , Chen Lingyun , Yang Wenzhu
Published: December 2019

The objectives were to investigate the effect of supplementing brewers’ spent grain (BSG) protein hydrolysates on rumen fermentation, nutrient digestibility, gas production and microbial protein synthesis in Rusitec. The experiment was a completely randomized design with four treatments assigned to sixteen fermenters in two Rusitec apparatuses. Protein hydrolysates from BSG were prepared using two proteases (Alclase and Flavourzyme) at 1% protease of BSG protein under optimum pH and temperature conditions. The treatments were control diet consisting of 10% barley silage and 90% barley concentrate (DM basis), control diet supplemented with alcalase hydrolysates (AlcH) or flavourzyme hydrolysates (FlaH) at 10 g/kg of diet DM, or antibiotics (Ant; 33 mg monensin + 11 mg tylosin/kg diet DM). The study consisted of 8 d for adaptation and 7 d for sampling. It was highest (P < 0.01) with control and AlcH, intermediate with FlaH and lowest with Ant for digestibility of DM (76.5, 76.1, 75.3, 72.7%), CP (75.1, 75.4, 73.4, 69.7%) and starch (90.7, 90.8, 89.5, 87.8%). Digestibility of NDF did not differ among control, AlcH and FlaH (average 39.3%), but higher (P < 0.01) than Ant (31.8%). Production of NH3-N (mmol/d) was greater (P < 0.01) in the order of AlcH and FlaH (average 4.1) > control (3.7) > Ant (2.6). The VFA production (average 54.3 mmol/d) and acetate/propionate ratio (average 0.79) were not different among control, AlcH and FlaH, but greater (P < 0.01) than Ant (48.9 mmol/d, and 0.69). Total gas production were not affected by treatments, but CH4 production (mg/g digested DM) was lower (P < 0.01) for FlaH (3.5) and Ant (2.2) than control (3.8). Microbial protein production (mg/d) was lesser (P < 0.05) for FlaH (476) and Ant (459) than control (502). These results indicate that adding FlaH in high-grain diet effectively reduced rumen CH4 production and CP degradability without affecting fibre digestion.
172 Effects of net energy levels on feed intake pattern and growth performance of growing-finishing gilts monitored using a computerized feed intake recording system
Authors: Zeng Zhikai , Huang YaKuan , Zhu Liqiang , Chen Zhiyuan , Yuan Z J , Zeng H , Sun D F , Wang Z , Yan Z C
Published: December 2019

This study evaluated the effects of dietary net energy concentrations on feeding behavior and growth performance of growing-finishing pigs monitored using a feed intake recording equipment (FIRE). Two hundred and sixteen (48.8 ± 5.6 kg) gilts were blocked by bodyweight and assigned randomly to 1 of 3 dietary treatments, which included low (2,350 kcal/kg), medium (2,450 kcal/kg), and high (2,550 kcal/kg) dietary NE levels. Pigs were housed in 18 pens for 68 d in four phases with 12 pigs and one FIRE station per pen. Bodyweight, feed consumption, and the amount of time and visit at the station of individual pigs were monitored every day by using FIRE. Pigs fed low NE diet spent more time (min) at the station during the first two weeks and visited the station more times with fewer amounts of time (min) per visit after two weeks compared with pigs fed medium and high levels of NE diets (P < 0.05). The speed (g/min) and amount (g/visit) of feed intake were lower (P < 0.05) during phase 3 and the overall period in low NE diet compared with pigs fed medium NE diet. Pigs fed medium NE diet tended to have a greater (P = 0.066) average daily feed intake at phase 4 than pigs fed low NE diet. Increasing NE levels linearly improved (P < 0.05) average daily gain, feed conversion ratio, and final BW during phase 3 and the overall period. However, the overall energy efficiency (Mcal NE/ kg gain) was linearly decreased with increasing NE levels. In conclusion, decreasing dietary NE to 2350 Mcal/kg resulted in more visits to feeders with slow ingestion speed compared with pigs fed diets with 2450 or 2550 Mcal/kg NE. Increasing dietary NE levels linearly improved daily gain and feed conversion ratio, but linearly decreased energy efficiency.
419 Academic performance and views toward community service from students engaged in service learning through a beef production course
Authors: Smith William B
Published: December 2019

Experiential learning is a feature common to post-secondary agricultural education. Similar to experiential learning opportunities, incorporation of service learning into post-secondary coursework is being encouraged more often. Our objective was to determine how community engagement and introduction of real-world problems in a species-specific production course would affect student performance and outlooks on community service. This experiment was conducted as a completely randomized design within the beef cattle production class during the spring 2019 semester at Tarleton State University. Thirty-eight students were enrolled in the course across two laboratory sections. Students in the first laboratory section were used as a control group. In the control, students were asked to draw from a selection of possibilities a description of herd size, sire and dam breed type, and county. Groups were asked to develop a management plan for a commercial cow-calf operation. Students in the second laboratory section were asked to brainstorm the most prevalent barriers to implementation of best management practices in cow-calf production. Groups were randomly assigned to each topic and were tasked with developing a tri-fold brochure addressing the barrier. They were instructed that this was being done as a service to the greater beef community and would be evaluated by industry representatives. Students in CON had more (P < 0.05) students that reported performing community service weekly or monthly prior to the study than TRT. Groups were similar (P ≥ 0.41) in their assessment of community needs and the role of college students in community service. Likewise, CON and TRT had similar (P ≥ 0.41) responses in having less time available for coursework and their service contributing to the betterment of the overall community. Results are interpreted to mean that incorporation of service learning opportunities does not influence student views on community service.
427 Creating experiential learning through roundtable discussion and debate exercises in an animals and society course
Authors: Mulvaney Donald R
Published: December 2019

An Animals and Society (AS) course has been in place departmentally for over 20 years. Similar courses and resource materials across academia are found in liberal arts arenas and may have titles of Anthrozoology, Human Animal Studies or Human Animal Interactions, among others. An examination of texts and learning resources for these classes reveal substantial depth and breadth and pervasiveness of the biases toward animal activism and anti-animal agriculture sentiments. Collectively, these indicators support the need for pedagogy to deeply investigate and deliberate ethical aspects of topics within AS courses. In our present course design, students participate in an in-class discussion activity, designed to simulate a well-informed town hall meeting where discussion and active participation are expected. Roundtable Discussion Panel exercises (RTDPs) and debates around a pre-determined topic were evaluated on exchange of ideas, information, cooperativity and solutioning using rubrics. A 20 question survey was administered to ascertain students’ perceived value and impact of the Debate vs RTDP exercises for dimensions of experiential learning. Participants built basic discussion skills, developed keen understanding of important animal issues and explored how groups can pool knowledge to reach consensus and solve problems. Participants were more engaged productive thinkers rather than emotional persuaders and assisted the larger group in creating ways to implement solutions discussed and highlighted organizational involvement in those actions/steps. Sixty-four percent preferred debate and 68% found it most challenging yet learned most from the RTDP. For debates, students saw themselves as cooperators but in panels, a majority viewed themselves as leaders. Well-designed RTDP’s and debates are a valuable pedagogy for animals and society courses.