bluuebunny/crossref_metadata_2025 huggingface dataset:
180 Screening the carbon footprint of intensive Korean dairy cattle farms: Transition towards low emissions’ production system
Authors: Ibidhi Ridha , Kim Tae Hoon , Bharanidharan Rajaraman , Thirugnanasambantham Krishnaraj , Kim Kyoung Hoon
Published: November 2020

In the context of global climate change, carbon footprint (CF) becomes an important sustainability indicator for dairy production systems. To mitigation the CF of the dairy sector, insight into greenhouse gases (GHG) emissions from individual farms is required. The objective of this study was to determine the primary contributors to GHG emissions at the farm-gate level, expressed as a carbon dioxide equivalents (CO2-eq), to produce one kg of fat-and protein corrected milk (FPCM). Primary data about farms’ management and feeding practices were collected from twelve dairy farms that belong to Gyeonggi-do province, which represent the most important region for milk production in South Korea. Allocation of GHG emissions between meat and milk was assessed as a physical allocation, 98% allocated to milk and 2% to meat (surplus of calves and culled cows). The CF of the evaluated farms averaged to 0.61 CO2-eq/kg of FPCM and ranged from 0.49 to 0.78 CO2-eq/kg of FPCM. Results indicated that the largest source of GHG comes mostly from enteric fermentation (83%), followed by manure management (6%), manure and fertilizer land application (8%) and energy consumption (3%). By type of gas emitted, methane accounted for 86% of total emissions, originating from enteric fermentation and manure management. Nitrous oxide and carbon dioxide accounted for 11.6 % and 2.8% of total GHG emissions, respectively. Lactating cows contributed by 70% of total GHG emissions, whereas dry cows, heifers and calves contributed by 5, 22 and 3%, respectively. Differences in GHG emissions from the evaluated farms could be explained by differences in feed quality and management practices through manure and fertilizers application on cropland. This study contributes to identify the main sources of GHG production in dairy farms, which can help to define mitigation strategies towards the transition to neutral carbon emissions of the dairy sector.
171 Inhibition of pure culture Salmonella Newport by camphor and eucalyptol in vitro
Authors: Seidel Darren S , Pisani Kristen , Hunnicutt Austin , Banks Quinterrius , Callaway Todd
Published: November 2020

Volatile oils have potent antimicrobial activities that have allowed them to be used as food preservatives for millennia. The impact of concentrations of the monoterpene volatile oils camphor and eucalyptol on the growth of the cattle and foodborne pathogen Salmonella Newport was evaluated by examining changes in optical density (600 nm). Cultures of S. Newport were grown in Tryptic Soy Broth (TSB) overnight and inoculated into fresh TSB tubes at an initial concentration of ~106 CFU/mL in the presence of monoterpene concentrations (0 – 9.85 mM) and were incubated at 39℃. Final optical density and maximum specific growth rates (h-1) were determined. Data were analyzed using a PROC GLM procedure in SAS 9.4 for a 2*5 repeated measure factorial. Overall, there was a concentration (P < 0.01) and a time by concentration (P < 0.01) effect, but no differences between monoterpene types (P = 0.28) were observed. Camphor and eucalyptol concentrations of 3.28 and 9.85 mM reduced (P < 0.05) S. Newport growth. The highest dose (9.85 mM) of camphor and eucalyptol immediately inhibited S. Newport growth. Maximum specific growth rate was reduced (P < 0.01) by both monoterpenes compared to controls, most particularly at 9.85 mM concentrations, but were not different between the two monoterpenes. Collectively, our results suggest that monoterpenes at high concentrations can reduce the growth of Salmonella Newport; however, to fully understand practical implementation of monoterpene effects on foodborne or animal pathogens, studies using both mixed culture and in vivo models are needed.

Tuesday, July 21, 2020
231 Effect of fat-embedded calcium gluconate on lactation performance in high-yielding multiparous dairy cows in a commercial dairy setting
Authors: Seymour Dave J , Carson Michelle , Daniel Jean-Baptiste , Sanz Victoria , Martín-Tereso Javier , Doelman John
Published: November 2020

Fat-embedded calcium gluconate fed as a dietary supplement has previously been shown to increase milk and component yields in lactating dairy cattle in controlled experimental settings. These responses are thought to be due to improvements in gut barrier function and health driven by increased butyrate supply from the fermentation of calcium gluconate in the hindgut. The objectives of the current study were to validate the effects of a fat-embedded calcium gluconate supplement offered during late gestation and early lactation on milk production and milk component yields in a commercial setting. From April to December 2019, 151 multiparous Holstein-Friesian dairy cows were assigned to one of four treatment sequences in a randomized complete block design within a 2 x 2 factorial design (negative control or supplement prepartum, and negative control or supplement postpartum). Outcomes pertaining to milk production, component yields and health parameters were recorded for the first 100 days of lactation. Yields of milk and all components increased (P ≤ 0.045) in response to postpartum supplementation, in agreement with previous studies. Milk protein content was 0.03% lower (P = 0.003) in animals receiving the supplement prepartum. Additionally, prepartum supplementation diminished the lactation performance response relative to animals receiving supplementation in the postpartum period only; lactation performance was partially ameliorated by subsequent postpartum supplementation. Overall, these results support previous work examining the lactation performance response to fat-embedded calcium gluconate supplementation in dairy cattle. Future controlled studies examining the effects of prepartum supplementation on subsequent lactation performance are warranted.
209 Appropriation of feedlot rations’ nutrient levels of imported cattle in central region of Turkey
Authors: Basalan Mehmet , Ekinci Ozan A
Published: November 2020

An experiment was conducted to determine the nutrient contents of concentrated feed and Total Mixed Ration (TMR) samples taken from 6 feedlot farms in Kirikkale province and their compensation of bulls’ requirements. In the province, 6 farms active in the feedlot business were identified, and their manufactured feed and TMR samples were taken at 15-day intervals, starting from cattle received either from Europe or South America. For all periods, in each sample, crude fat (EE), crude protein (CP), crude ash (CA), crude cellulose (CS), dry matter (DM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) levels were determined based on Association of Official Analytical Chemists (AOAC) methods. Metabolizable Energy levels of Total Mixed Rations (TMR) and concentrate part of feeds were calculated based on Turkish Standard Institute (TSE) method. The determined values were evaluated according to animal numbers (herd size) in feedlot and fattening periods. It was determined whether the size of the feedlot farm has an effect on TMR preparation and the nutrients in TMR are matching with the beef cattle requirements during the fattening period. Data was analyzed by using one-way ANOVA and means were separated by using LSD. Results showed that CP levels of the TMRs were significantly higher than the requirements listed in Nutrient Requirements of Beef Cattle published by National Research Council (NRC) in both cattle receiving fattening periods (0–45 days and 45–90 days) (P < 0,05). Additionally, cattle feeders fed their cattle with similar protein levels independent from the size of feedlot (P > 0,05), unexpectedly. Although it was compared with requirements, energy levels were similar in all feedlots (P > 0,05). All determined nutrients levels of concentrate parts of TMRs in large and small herds were similar (P > 0,05). In conclusion, considering that this situation absolutely increases cost of fattening and may cause metabolic diseases.
227 Evaluation of mixer performance in cattle finishing diets of varying physical characteristics
Authors: Buckhaus Elizabeth M , Smith Zachary K
Published: November 2020

An experiment was conducted to evaluate batch fraction (BF), physical characteristics (DIET), and mixing duration (DUR) on long particle distribution in finishing diets. Diets were mixed in a 2.35 m3 horizontal mixer. The experiment was designed as a 5×3×2 factorial arrangement with nine replications per simple mean. Factors included 1) BF (n = 5), 2) DIET (n = 3) containing no corn-milling by-product (CON), a dry-corn milling by-product [47.45 ± 1.015% DM (as-is basis); DRY], or a wet-corn milling by-product [43.67 ± 1.786% DM (as-is basis); WET], and 3) mixing duration (n = 2) of 20 or 25 revolutions. Diets contained a 1:1 blend of DRC:HMC, the corn-milling by-products replaced the corn blend (20% total diet DM inclusion), grass hay (6% DM inclusion), liquid supplement (5% DM inclusion), and a meal supplement (7% DM inclusion). Data were analyzed as a CRD using the GLIMMIX procedure (SAS Inst., Inc., Cary, NC) using a multinomial approach. Samples of the total mixed ration (TMR) were subjected to separation via the Penn State Particle Separator. The dependent variable of interest was the portion of the TMR retained on the 19 mm sieve. No interactions were detected (P ≥ 0.49). There was an 87.1% (P = 0.01) increase in retention on the 19 mm sieve for last BF compared to the first BF. Diet influenced (P = 0.04) 19 mm sieve retention, there was 10.2% less TMR retained on the 19 mm sieve for DRY versus WET; CON was intermediate. Mixing duration did not influence (P = 0.73) 19 mm sieve retention. These data indicate that as the mixer unloads there can be nearly double the amount of roughage fed; differing physical characteristics of the diet only moderately influence the true roughage content fed. Differing roughage content delivered depending upon the BF could influence daily intake, feed efficiency and alter observed to expected ratios of dietary net energy.
191 Effects of injectable vitamin C at weaning and prior to transit on growth performance and immune function of beef steers
Authors: Beenken Aubree M , Deters Erin L , Dornbach Colten W , Hansen Stephanie L , McCann Joshua C , Shike Daniel W
Published: November 2020

Ninety-one early-weaned (65 ± 11 d) Angus steers (92 ± 4 kg) were blocked by age to a 2 × 2 factorial examining effects of injectable vitamin C (VC) at weaning and/or prior to transport to the feedlot on antibody titers and growth performance. Injections (20 mL/steer) of VC (250 mg sodium ascorbate/mL) or saline (SAL) were given at time of weaning on d 0 (WEAN) and/or prior to a 6 hr trucking event to a feedlot on d 49 (TRANS). Steers were given booster vaccinations on d 0. Steers were weighed on d 0, 1, 14, 48, 49, 64, 106, and 107. Blood was collected (12 steers/treatment) on d 0, 1, 2, 14, 49 (pre- and post-transit), 50, and 51. Data were analyzed via Proc-Mixed of SAS (experimental unit = steer; n = 22–23/treatment) with fixed effects of block, WEAN, TRANS, and WEAN × TRANS. Plasma ascorbate concentrations for weaning (d 0, 1, and 2) and transit (d 49-pre-trucking, 49-post-trucking, 50, and 51) were analyzed as repeated measures (repeated effect = day). Plasma ascorbate concentrations were greater on d 1 and 2 for steers that received VC at weaning (VC = 19.6, SAL = 8.8 ± 1.26 µM; WEAN × day P < 0.01). Similarly, ascorbate concentrations were greater on d 49 post-trucking, 50, and 51 for steers that received VC pre-transit (TRANS × day P = 0.01). Treatments did not affect bodyweight or average daily gain throughout the trial (P > 0.32). There were no effects of treatment on serum Bovine Viral Diarrhea Virus type 2 antibody titers on d 14 or 51 (P > 0.33). An injection of VC administered to early weaned beef steers at weaning or pre-transit increases plasma ascorbate concentrations but does not improve growth performance or antibody response to vaccination booster.
204 Effects of sorghum silage kernel processing on intake and apparent total tract digestibility of beef heifers
Authors: Podversich Federico , Roskopf Sergio , Abdelhadi Leandro , da Silva Gleise Medeiros , Tarnonsky Federico , Fernandez Federico , Sanchez Federico , Batista Dubeux Jose Carlos , Ferraretto Luiz , DiLorenzo Nicolas
Published: November 2020

This study evaluated the effect of different kernel processors in terms of nutrient digestibility of whole-plant sorghum silage. Grain sorghum (hybrid ADV1250IG, Advanta Seeds, Irving, TX) was harvested at the hard-dough stage with a Class Jaguar 960 and 930 harvesters, switching the kernel processor to generate the forage material for the three treatments: conventionally processed (CONV), unprocessed (UN), and shredlage processed (SHRED). The material was bagged in three 2.7 m bags and allowed to ferment for 1 mo. Twenty-four black Angus heifers (13 ± 1 mo, 267 ± 10.9 kg of BW) were randomly assigned to treatments (8 heifers/treatment) and allocated to individual pens (36 m2) with access to feed and water. Diets were ad libitum sorghum silage from each respective treatment, plus soybean meal top-dressed at 0.5% of BW. After a 15-d adaptation period, feed and feces were collected for 5 d. Feed was offered once daily, and orts were collected the following day. Fecal samples were collected twice daily and apparent total tract digestibility was determined using indigestible NDF as a marker. Data were analyzed as a completely randomized design using heifer as the experimental unit, and initial BW as a covariate. Dry matter (DM) intake as a percentage of BW (P = 0.09) and NDF digestibility (P = 0.06) tended to differ among treatments, where CONV tended to be lesser than UN (P = 0.08), whereas SHRED was intermediate. Digestibility of DM was affected by treatment (P = 0.05), where UN (71.3%) tended (P = 0.06) to be greater than CONV (67.9%), while SHRED (70.8%) did not differ from any of the treatments (P ≥ 0.12). In conclusion, kernel processing affects nutrient digestibility of sorghum silage. Differences in ruminal kinetics and fermentation parameters, resulting from contrasting particle sizes, grain processing and sorting, may help explain these findings.
189 Evaluation of Hybrid Rye on Growth Performance, Carcass Traits, and Efficiency of Net Energy Utilization in Finishing Steers
Authors: Rusche Warren C , Walker Julie , Brattain Rebecca S , Smith Zachary K
Published: November 2020

Predominately Angus steers (n = 240, initial shrunk BW 404 ± 18.5 kg) were used in a 117d feedlot experiment to evaluate the effect of hybrid rye (KWS Cereals USA, LLC, Champaign, IL; Rye) as a replacement for dry-rolled corn (DRC) on growth performance, carcass traits, and comparative net energy value in diets fed to finishing steers. Rye from a single hybrid (KWS Bono) with an ergot alkaloid concentration of 392 ppb was processed with a roller mill to a processing index (PI) of 78.8 ± 2.29. Four treatments were used in a completely randomized design (n = 6 pens/treatment, 10 steers/pen) where DRC (PI = 86.9 ± 4.19) was replaced by varying proportions of Rye [DRC:Rye, DM Basis (60:0), (40:20), (20:40), and (0:60)]. Liver abscess scores and carcass characteristics were collected at the harvest facility. Carcass-adjusted performance was calculated from HCW/0.625. Performance-adjusted NE was calculated using carcass-adjusted ADG, DMI, and mean equivalent shrunk BW with the comparative NE values for Rye calculated using the replacement technique. Data were analyzed using the GLIMMIX procedure with pen as the experimental unit. Means were separated using linear and quadratic contrasts. Replacing DRC with Rye linearly decreased (P ≤ 0.01) carcass-adjusted final BW, ADG, DMI and G:F. Feeding Rye linearly decreased HCW and LM area (P ≤ 0.04). Distributions of liver scores and USDA grades for quality and yield were unaffected by treatment (P ≥ 0.09). Using observed performance from d 19 to d 117 (period when steers were on final diet), the estimated replacement NEm and NEg values for Rye were 1.93 and 1.26 Mcal/kg, respectively. Rye can be a suitable feed ingredient in finishing diets for feedlot steers with the optimal inclusion in this experiment at 20% of DM. Complete replacement of DRC with Rye depressed DMI, ADG, and G:F.
184 President Oral Presentation Pick: Supplementation of Angus crossbred steers with avian-derived polyclonal antibody preparations against ruminal methanogenic Archaea alters ruminal fermentation and decreases ex situ methane production
Authors: Garcia-Ascolani Mariana E , Ruiz-Moreno Martin , Schulmeister Tessa M , Tarnonsky Federico , Roskopf Sergio , Podversich Federico , da Silva Gleise Medeiros , Martinez Juan Vargas , Hackmann Timothy J , Batista Dubeux Jose Carlos , DiLorenzo Nicolas
Published: November 2020

An experiment was conducted to evaluate the effect of supplementing fourteen ruminally cannulated Angus crossbred steers with polyclonal antibody preparations (PAP) from avian origin against ruminal methanogens Methanobrevibacter gottschalkii Ho (PAP-Ho) and M. ruminantium M1 (PAP-M1). Steers were fed bermudagrass hay ad libitum and 2 kg d-1 of corn gluten feed. A randomized block design was used, with a 3 × 2 + 1 factorial arrangement, replicated in three periods. Factors were proportions of PAP against Ho and M1 in the mixture (100:0, 50:50, and 0:100 Ho:M1) and level of supplementation of each mixture (3 or 6 mL d-1). Control steers had no PAP supplementation. Steers were adapted to the feeding regimen for 14 d, with no PAP supplementation, followed by a 21-d treatment period. Ruminal fluid (RF) from each steer (experimental unit) was collected before PAP supplementation (h 0) and every 4 h (for a 24-h period) on d 0, 14, and 21 of treatment period for the determination of ruminal fermentation profile. In addition, RF collected at h 0 was individually mixed with McDougall’s Buffer (1:3 ratio) to inoculate serum bottles and polycarbonate tubes for the determination of methane production and in vitro fermentation profile. Treatment means were evaluated by preplanned, non-orthogonal, single-degree-of-freedom contrasts. There was no effect (P ≥ 0.48) of level of inclusion on ex situ methane production (ESMP). When PAP-M1 was used either alone or in combination with PAP-Ho, ESMP decreased (P ≤ 0.05) compared to control. Ex situ ruminal fermentation profile was not different (P ≥ 0.12) across treatments. In vivo molar proportion of propionate tended to be greater (P = 0.10) with supplementation of PAP-M1, alone or combined, compared with control. Polyclonal antibody preparations against ruminal methanogens have the potential to decrease enteric methane emissions.
206 Characterization of the Rumen Bacterial Communities of Grass-fed and Grain-fed Bison Heifers
Authors: Rueda Anlly M Fresno , Griffin Jason , Kruse Carter , St-Pierre Benoit
Published: November 2020

The ruminal bacterial environment of the North American bison has remained largely unexplored. The current study aimed to compare the diversity and composition of ruminal bacteria between bison heifers on two different diets. Stomach tubing was used to collect rumen fluid from lifetime grass-fed heifers between 27 and 30 months of age distributed between 2 ranches located in Standing-Butte (n = 17), SD, and Blue-Creek (n = 17), NE, respectively. A second set of samples was collected after the same individuals had been transitioned to a grain-based diet for 100 days. Bacterial composition was determined by Illumina MiSeq (2×300) sequencing of PCR amplicons generated from the V1-V3 region of the 16S rRNA gene. Next-Generation Sequence data was analyzed using a combination of custom Perl scripts, and publicly available software (Mothur v.1.40, RDP classifier and NCBI Blast). Taxonomic analysis identified Bacteroidetes and Firmicutes as the dominant phyla across all samples analyzed. A total of 61,746 and 68,437 species-level Operational Taxonomic Units (OTUs) were identified in grass-fed heifers, in contrast to 15,003 and 23,458 OTUs that were found in the same animals on a grain-based diet. A comparative analysis using the most abundant OTUs from each group was conducted using the Kruskal-Wallis sum-rank test. In the Standing Butte heifers, 24 abundant OTUs were found to be different between diets (P < 0.05), including BP_31-10446 (µ grass = 0.3% vs µ grain = 3.2%) and BP_25-00404 (µ grass = 0.4% vs µ grain = 4.1%). In the Blue Creek heifers, 20 of the most abundant OTUs were found to be different between diets (P < 0.05), including BP_18-00869 (µ grass = 1.4% vs µ grain = 0.4%) and BCRC_1-00422 (µ grass = 0.07% vs µ grain = 4.4%). Together, these results indicate that the rumen of the North American bison harbors highly diverse bacterial communities that undergo dramatic changes in response to changes in diet.
207 Effects of increasing dietary metabolizable protein in lightweight beef calves
Authors: Redden Miles D , McCann Joshua C , Shike Daniel W
Published: November 2020

The objective was to assess the effect of increasing metabolizable protein (MP) supply to lightweight beef steers on total tract digestion, N balance, and performance. The 2016 Beef Cattle Nutrient Requirements Model (BCNRM) prediction of MP requirements in lightweight beef steers (less than 250 kg) is limited by available data. Spring-born Angus steers (n = 12; BW = 166 +/- 10.7 kg) were weaned at 97 ± 10 d of age, backgrounded 42 d, implanted with Component TE-IS, stratified by BW, and assigned to one of four treatments in a crossover design with two 19 day periods. Each period included a 12-day adaptation followed by a 6-day collection period of total orts, feces, and urine. Treatment diets were formulated to provide 0.62 (MP1), 0.76 (MP2), 0.89 (MP3), and 1.01 (MP4) kg MP per day. Metabolizable energy was similar across diets (2.14 Mcal/kg). Data were analyzed using the Mixed procedure of SAS. Dry matter intake was not affected by treatment (P = 0.92) and averaged 5.7 kg per d. Average daily gain (ADG) tended (P = 0.06) to increase quadratically with MP provision with 1.45, 1.72, 1.93, and 1.71 kg per day for MP1, MP2 MP3, and MP4, respectively. Feed efficiency (G:F) also increased quadratically (P = 0.05) at 0.27, 0.32, 0.35, and 0.31 for MP1, MP2 MP3, and MP4, respectively. Greater dietary MP linearly increased (P < 0.01) N intake, N absorption, and urinary N. Fecal N and retained N were not affected by treatment (P ≥ 0.56). Apparent organic matter digestibility increased linearly (P ≤ 0.01). Increasing MP resulted in a linear increase in N absorption but a quadratic response for ADG, suggesting MP greater than 0.89 kg per d may exceed MP requirements for steers weighing 166 kg and consuming a 2.14 Mcal/kg diet.
236 Comparison of ultrasound scanned loin eye muscle characteristics and back-fat depth measured in lean muscle selection and control Katahdin sheep flock
Authors: Wuliji Tumen , Baughman Christopher , Epple-Farmer Jessica , Markway Jeremiah , Wilbers Luke , Bax Amy
Published: November 2020

Sheep farming is an important enterprise for many farmers in US, and meat is a viable protein resource for human nutrition. However, increasing concern for health aspects of meat consumption has led consumers to demand a higher ratio of lean to fat tissues. Application of ultrasound carcass scanning in meat animal selection and marketing as a performance prediction will enhance the selection efficiency, accuracy and profitability. One hundred and sixty two mixed-age Katahdin ewes were evenly divided into a high lean muscle selection (n = 81) and control (n = 81) flock based on the prescreened ultrasound measures, including loin eye muscle area (LEA), loin eye muscle width (LEW), and depth (LED), and back-fat depth (BFD). The LEA is measured between the 12th and 13th ribs lateral and perpendicular to the vertical column and parallel to rib covering the longissimus dorsi muscle. Live animal measurements were conducted using ultrasound scanner fitted with a 3.5 MHz linear transducer (ExaGo, France) prior to fall breeding schedules. Live weight (LWT), body condition score (BCS) and FAMACHA score (FAM) were recorded. Data were analyzed using GLM procedures of SAS statistics. There was no difference between selection and control flocks for LWT, BCS and FAM; however, LEA, LEW, LED and BFD were significantly (P < 0.05) greater for the lean selection over control flock (Table 1). The correlation coefficients (P < 0.01) were found as moderate (r = 0.6) to high (r = 0.8) among LED, LEA, LEW and BFD, whereas these traits showed lower (r = 0.4) but significant (P < 0.01) correlations with LWT. The results indicate that lean muscle selection in sheep with ultrasound scanning of longissimus muscle characteristics will enhance the production efficiency and genetic gain and facilitate producing a high value meat product.
238 Reproductive and lactation management for year-round ewe milk production with non-traditional dairy breeds
Authors: Kochendoerfer Nikola , Thonney Michael L , Brown Dan L
Published: November 2020

The ability of Finnsheep x Dorset meat ewes to achieve high milk yields in short and frequent 73-day lactation periods on the STAR accelerated lambing system in a year-round dairy system was tested together with ewe reproductive success. Ewes (n = 53) were managed in 3 groups and enrolled in a triply replicated (for management group) 3′3 Latin square design (3 pens, 3 lactations, 3 diets). Diets (L-SH, M-SH, H-SH) contained 31.6, 36.3, 40.0% aNDFom and 41.3, 37.2, 31.9% NFC. Milk was recorded at each 2X milking, ewes and lambs weighed weekly. Ewes were bred to lamb with 219-day lambing intervals. To facilitate breeding, progesterone CIDRs were employed for 7 days prior to breeding during increasing day-light period breeding months. Individual lactation curves were fitted to 127 evaluated lactations. Lactation parameters were analyzed with a model including Square Number, Pen and Lactation within Square Number, and Diet, with 3 to 6 ewes in each cell of each Latin Square. Ewes offered the M-SH diet produced more (P = 0.03) milk/d (1.40, 1.58, and 1.37 ± 0.07 kg) and higher (P = 0.02) lactation yields (95.8, 109.6, and 93.0 ± 5.29 kg), compared with ewes offered the L-HS or H-SH diets, respectively. Investigating the effect of breeding season (January, March, June, August, and October) on reproductive success, conception rates ranged between 83.3 and 94.1% and were not affected by breeding season. Litter sizes were lower for matings in March and June (P < 0.05) compared to June, August, and October. Average daily gains of lambs raised artificially ranged between 283 and 328 g ± 11.2 g per day and were significantly higher for January-born lambs than for March born lambs (P < 0.001). Both milk production and reproductive success were high for ewes milked year-round in short and frequent lactations.
244 The effect of a high-fiber feeding program for replacement gilts on body weight and composition at breeding
Authors: Gregory Nicole , Farmer Chantal , Friendship Robert , Huber Lee-Anne
Published: November 2020

Sixty-three gilts were recruited at 90 days of age to evaluate the effects of a high-fiber gilt development feeding program on body weight and composition at breeding. Gilts (initial BW 50.9 ± 0.9 kg) were housed individually and randomly attributed to one of four feeding programs: [1] commercial diet fed ad libitum (CON), [2] commercial diet fed 10%, or [3] 20% below ad libitum, and [4] a high-fiber diet fed ad libitum (25% more fiber than the commercial diet and energy density reduced by 5%; FIB). Gilts received the feeding program between 90 days of age and breeding at ~190 days of age. Body weight and feed disappearance were determined weekly. Backfat depth was determined at 90, 145 (puberty), 160, and 190 (breeding) days of age. Over the entire experimental period, CON and FIB gilts had greater ADFI (mean of 3.50 ±0.07 kg) compared to 10% (2.95 ± 0.06 kg) and 20% gilts (2.70 ± 0.07kg; P < 0.05). The FIB feeding program reduced total energy and lysine intakes to amounts similar to 10%; both intakes were less than CON but greater than 20% gilts (P < 0.05). The ADG of FIB was less between days 145 (puberty) and 160 of age compared to CON gilts (0.86 vs. 1.09 ± 0.07 kg; P < 0.05). At breeding, FIB and 10% weighed less (146.5 ± 1.6 kg) than CON (152.7 ± 1.6 kg) and more than 20% gilts (138.7 ± 1.5 kg; P < 0.05). The FIB had less backfat than CON at breeding (14.9 vs. 16.7 ± 0.5 mm; P < 0.05), but did not differ from 10% or 20% gilts. In conclusion, the FIB feeding program limited energy intake, growth, and body fatness of gilts at breeding, even though gilts were offered feed ad libitum. Therefore, high-fiber feeding programs could be a practical means to control growth rates of developing gilts in commercial scenarios.
246 Maternal Programming of the Piglet Microbiome from Birth to Weaning
Authors: Law Kayla , Lozinski Brigit , Torres Ivanellis , Hillbrands Adrienne , Nelson Emma , Johnston Lee , Gomez Andres
Published: November 2020

The objective of this study was to investigate seeding of the piglet microbiome, in the context of maternal programming in pre/perinatal environments. Maternal programming refers to maternal factors that predetermine offspring development and health. We hypothesized that increased sanitation level in maternal environments affects development of piglet fecal and nasal microbiomes, and physiological performance. Six sows were allocated randomly to two treatment groups: farrowing stalls cleaned with (D; n = 3) or without (ND; n = 3) disinfectant. Swabs were collected from stall floors, drinkers and feeders, and from sows’ vaginal, rectal, oral and udder surfaces at d109 of gestation and the day before farrowing. Fecal and nasal swabs were collected from piglets at days: 0 (within 24h of birth), 7, 14, and 21 postpartum. Nine piglets were selected randomly from each sow (n = 27/treatment) for microbiome analyses. DNA was extracted from swabs and the V4 variable region of the 16srRNA bacterial gene was sequenced on the MiSeq platform. Sequence data were analyzed using DADA2 and various packages within the R statistical software. Although environmental microbiomes were different between D and ND stalls (PERMANOVA, R2 = 0.474, P = 0.031) after cleaning, no compositional differences were detected among any D or ND sow samples. However, at d0, ND compared with D piglets exhibited higher gut (Shannon’s H, P = 9.131e-08) and nasal (P = 6.164e-08) alpha diversity. ND piglets also displayed greater nasal bacterial diversity at d21 (P = 0.036), and different gut (R2 = 0.06–0.129, P = 0.001) and nasal (R2 = 0.136–0.196, P = 0.001) microbiome compositions across all timepoints. However, D piglets exhibited higher average birth (P = 3.773e-05) and weaning weights (P = 5.803e-06) compared to ND piglets. These results indicate that sanitation level during farrowing persistently alters swine microbiomes and growth performance.
249 Predicting body weight of finishing pigs using machine and deep learning algorithms
Authors: He Yuqing , Tiezzi Francesco , Maltecca Christian
Published: November 2020

Understanding and exploiting feeding patterns in swine could allow a reduced feed waste and minimized sorting losses. The objectives of this study were to evaluate the ability to predict whether a pig reached a target weight at finishing by using several algorithms and to compare the prediction using varying amounts of data during the growing period. Data were collected on 655 pigs from 75 to 166 days of age. Pigs were housed with 8 to 15 pigs and a Feed Intake Recording Equipment in each pen. Feed consumption, occupation time, and body weight per visit were recorded when a pig visited the feeder. Lasso Regression (LS), a machine learning algorithm: Random Forest (RF), and a deep learning algorithm: Long-short Term Memory (LSTM) network, were used to forecast whether pigs can reach 129 kg at the finishing stage (159–166 d). Times of visits, a sum of feed consumption, a sum of occupation time in the feeder every day, and age were used as predictors. Data were split into 6 slices by 14 days and used to calibrate the models and their predictive ability was tested with data corresponding to the last 8 days of the study period. The greatest correlation coefficients were 0.799, 0.828, and 0.868 using slice 6 (145–158 d) to train the LS, RF, and LSTM, respectively. The LS and LSTM algorithms had a smaller root mean squared error, 0.863 and 0.895 compared to the RF with 1.375 in the prediction. Overall, LS and LSTM performed best. Predictions using data closest to the finishing stage proved better. This study connects the dynamics of feeding behavior and feed intake data to growth using prediction methods that will hopefully accelerate the mainstream application of electronic feeders in pig production systems.
245 Effect of space allowance, mixing and phase feeding on productive performance and body lesions of grow-finisher pigs in pens with a single wet-dry feeder
Authors: Montoro Jordi Camp , Solà-Oriol David , Muns Ramon , Manzanilla Edgar G
Published: November 2020

The study aimed to quantify the effect of space allowance (SA), mixing and phase feeding on productive performance and body lesions (BL) as a proxy for aggression in single wet-dry feeder pens during the grow-finisher stage. Pigs were moved as litters to the finisher accommodation at 11 wks of age and assigned in two SA: 0.96 m2/pig (HSA; n = 15 pens; 10 pigs/pen) and 0.78 m2/pig (LSA; n = 15 pens; 13 pigs/pen). Mixing was applied to 5 pens of each SA leading to a 2 × 2 factorial arrangement. At 15 wks of age, phase feeding was applied to 5 litter pens of each SA leading to another 2 × 2 factorial arrangement: SA and diet (0.82, LD, or 0.95, HD, g/MJ SID Lys:NE). BL were counted at anterior, mid and posterior locations of the body at 12, 16 and 21 wks of age. Pen feed intake and BW were recorded every 2 wks until 21 wks of age. ADG, ADFI and FCR were calculated and analyzed using GLMM with pen as the experimental unit. Model included initial BW, diet or mixing, SA and their interaction as fixed effects. Alpha for determination of significance was 0.05 and trend were identified at 0.10. HD pigs had higher ADG (P = 0.011) and lower FCR (P = 0.005) compared to LD pigs (Table 1). Non-mixed pigs had higher ADG (P = 0.004), ADFI (P = 0.007) and lower FCR (P = 0.079) than mixed pigs (Table 1). LSA pigs had 48.6, 43.6 and 101.3% more BL than HSA pigs at 12, 16 and 21wks of age (P < 0.05; Table 1). Mixing was not a source of variation in BL (P >0.05; Table 1). Mixing and dropping SID lys:NE from 0.95 to 0.82 g/MJ affect growth to a similar extent. An increase on BL in LSA pigs indicates that 0.78 m2/pig is detrimental to animal welfare in wet-dry feeder pens despite following EU legislation.
243 Ileal Terminal Starch Hydrolytic Activity Is Increased in Association with Improved Growth and Feed Efficiency in Weaning Pigs Fed a Therapeutic Multi-antimicrobial-supplemented Diet
Authors: Chen Jiali , Wang Min , Archbold Tania L , Wang Weijun , Fan Wenyi , Yin Xindi , Cheng Laurence , Fan Ming Z
Published: November 2020

Understanding roles of prescribed in-feed therapeutic multi-antimicrobials in affecting the small intestinal terminal starch digestive enzyme activity in improving weaning pig growth and feed utilization may shed light on developing novel alternative strategies to reduce uses of antimicrobials. A total of 125 crossbred barrows, weaned on d 19–21 with an average initial BW of 6.9 ± 0.1 kg, were randomly assigned to two corn, SBM and dried whey powder based diets for 21 d according to a randomized complete block design. The multi-antimicrobial diet was supplemented with aureomycin 220, tiamulin 31.2 and ZnO 2,358 at mg/kg diet. The growth performances including final BW (control, 13.9 ± 0.2 vs. antimicrobials, 15.0 ± 0.2 kg), ADG (control, 0.307 ± 0.009 vs. antimicrobials, 0.355 ± 0.009 kg/d), ADFI (control, 0.425 ± 0.012 vs. antimicrobials, 0.455 ± 0.013 kg/d) and F:G (control, 1.39 ± 0.03 vs. antimicrobials, 1.28 ± 0.03 kg/kg) were improved (P < 0.05; n = 25 pens; 5 barrows/pen) compared to the non-antimicrobial control diet. The combined enzyme kinetics of the jejunal and the ileal maltase-glucoamylase (MGA) and sucrase-isomaltase (SI) activity were determined with the jejunal and the ileal homogenates by using maltose (0–60 mM in incubation mixture). The combined jejunal and the ileal MGA-SI affinity Km values and the combined jejunal MGA-SI maximal activity Vmax values were not different (P > 0.05) between the two diet groups. However, the combined ileal MGA-SI Vmax (nmol·mg protein-1·min-1) was increased in the antimicrobial diet (P < 0.05; control, 125.6 ± 10.84, n = 13 pigs vs. antimicrobials, 170.8 ± 12.15, n = 11 pigs) in comparison with the control diet. The Pearson’s correlation analyses revealed that the combined ileal MGA-IS Vmax of hydrolyzing maltose was associated with ADG (P = 0.0669; r = 0.38; n = 24 pigs) and feed efficiency (F:G; P < 0.05; r = -0.53; n = 24 pigs). Our results suggest that in-feed therapeutic multi-antimicrobials could improve the distal small intestinal terminal starch digestive enzyme MGA-SI activity, thus improving growth and feed efficiency in weaning pigs.
241 Metoclopramide induces low-level hyperprolactinemia to increase milk production in sows
Authors: Mathews Alice T , Banks Carmen M , Trott Josephine F , Sainz Roberto D , Farmer Chantal , Pendergast Izabella I , Hovey Russell C
Published: November 2020

Inadequate milk production by sows often limits the growth rate of piglets. A successful lactation requires prolactin (PRL)-induced differentiation of the alveolar epithelium within the mammary glands of sows between gestation days 90–110 (G90-110). We hypothesized that late gestational hyperprolactinemia in primiparous sows induced by feeding the dopamine antagonist metoclopramide (MET) would enhance mammary epithelial differentiation, milk yield, and piglet growth rate, and that these effects would carry over into a subsequent lactation. Twenty-six gilts were randomly assigned to receive either MET (n = 13, 0.8mg/kg) or vehicle (CON, n = 13) twice daily from G90-110. On G90, circulating PRL levels peaked 45 min after MET dosing (P < 0.001) then returned to baseline 3 h later. This response occurred daily out to G104 (P < 0.05). Treated gilts had increased alveolar lumen diameter on G110 (P < 0.05), though feed intake, body weight, and carcass fat percent were not different during pregnancy or lactation. Piglets born to treated sows had increased body weight and average daily gain on lactation days 14 and 21 (P < 0.05). Piglet milk intake was estimated from deuterium oxide dilution. While milk intake by piglets nursing MET sows was not statistically different from those nursing CON sows on day 21 of lactation (P = 0.18), there was a greater increase in milk consumption by piglets born to MET-treated sows between days 9 and 21 of lactation than for those in CON litters (P < 0.001). In one group of second parity sows, milk yield was increased during their second lactation with no additional treatment (P < 0.05) and their carcass fat dropped by 14% (P < 0.05). These findings demonstrate that MET-induced hyperprolactinemia in pigs during late pregnancy can increase milk yield and piglet growth rate, and this response can be sustained into a second lactation in some sows.
400 Functional amino acids to improve pig robustness
Authors: Columbus Daniel A
Published: November 2020

Pigs are continuously exposed to pathogens and immune-stimulatory antigens that negatively impact animal productivity. In general, this decrease in productivity is the result of reduced feed intake and increased demand for nutrients to mount an immune response. In addition, immune system stimulation alters amino acid metabolism and utilization, with amino acids redirected from growth towards supporting the immune response. A number of previous studies have shown that nutrient requirements for some amino acids, such as methionine, tryptophan, and threonine, are higher in immune-challenged vs. healthy animals, and supplementation with these “functional” amino acids may improve performance and the immune response. In addition to effects on whole-body growth, both dietary composition and immune challenge result in significant physiological alterations to the gastrointestinal tract, including changes in gut motility, permeability, digestive enzyme secretion, absorptive capacity, and mucin production. Alterations to the gut epithelium induced by dietary protein and/or fiber content may lead to increased susceptibility to pathogens and immune stimulation. Functional amino acids have been shown to be important in the maintenance of gut barrier function as well as immune response. An increased understanding of the interaction of nutrition and the pig’s immune response will be a key component in efforts to reduce feed costs and antibiotic use while improving animal robustness and profitability of the swine industry.
255 President Oral Presentation Pick: Exposing Undergraduate Students to Extension: Delivering Producer Education Presentations
Authors: Bullock Darrh , Lehmkuhler Jeffrey , Anderson Leslie , Arnold Michelle
Published: November 2020

Recent communications with livestock industry employers suggest that students seem to be prepared to publicly deliver scientific information to peers, but struggle to present comprehensible science-based information to lay audiences. Based on this premise, a producer education presentation at local Extension offices was incorporated into the Beef Cattle Science Course. The course has four core areas (health, nutrition, reproduction and genetics) with supporting instructors from meat science, forages, agricultural economics and biosystems/agricultural engineering. Students are presented a case study in each of the four focus areas and are required to submit a written report addressing the issues in the case study. At midterm, students are divided into groups of four or five and assigned to a local county. Students are required to contact the county agent and develop an educational program, with one student presenting on each of the core areas, with environmental stewardship as a fifth option. Each student must first prepare an outline and send it to the corresponding faculty member for feedback prior to developing a 15-minute PowerPoint presentation. Each student is required to deliver their presentation to instructors to receive feedback prior to the Extension meeting. Each student group must develop a promotional flyer for the agent’s use. The producer educational programs are delivered in the evening to 15–50 producers, followed by audience questions. Additionally, students are tasked with developing, administering and summarizing an assessment tool. On the last day of class we have an informal discussion of this experience. For the five years that we have incorporated this into the course, the consensus is that students initially hate the concept but love the experience and appreciate the value after presenting. Agent and producer feedback have been positive.
269 Influence of the maternal rumen microbiome on development of the calf meconium and rumen microbiome
Authors: Woodruff Kelly , Hummel Gwendolynn , Austin Kathleen , Smith Travis , Cunningham Hannah
Published: November 2020

Optimization of host performance may be achieved through programming of the rumen microbiome. Thus, understanding maternal influences on the development of the calf rumen microbiome is critical. We hypothesized that the cow maternal rumen microbiome would influence colonization of the calf rumen microbiome. Our objective was to relate the microbiome of the cow rumen fluid prior to parturition (RFC) and at weaning (RFCw) to the calf’s meconium microbiome (M) and calf rumen fluid microbiome at birth (RFd1), d 2 (RFd2), d 28 (RFd28), and weaning (RFNw). Multiparous Angus crossbred cows (n = 10) from the University of Wyoming beef herd were used. Rumen fluid was collected from the cows prior to parturition and at weaning. Immediately following parturition, meconium and rumen fluid were collected from the calf. Rumen fluid was collected again at d 2, 28, and at weaning. Microbial DNA was isolated and 16S rRNA sequencing was completed on the Illumina MiSeq. Sequence data were analyzed with QIIME2 to determine both alpha and beta diversity by sample type and day. Alpha diversity metrics reported similarities in the early gut microbiome (M, RFd1, and RFD2; q ≥ 0.12) and between the cow and calf at weaning (q ≥ 0.06). Microbial composition as determined by beta diversity differed in the early rumen microbiome (RFd1, RFd2, and RFd28; q ≤ 0.04). There were similarities in composition between M, RFCw, and RFd1 (q ≥ 0.09). These data can be used to develop hypotheses for the pathway of colonization in the early gut and can provide insight into management practices affecting the microbiome, improving host performance.
270 Evidence for the amnion-fetal gut-microbial axis in late gestation beef calves
Authors: Hummel Gwendolynn , Woodruff Kelly , Austin Kathleen , Smith Travis , Cunningham Hannah
Published: November 2020

As the most immediate membrane surrounding the fetus, the amnion carries great potential as a microbial source of inoculation for the calf’s rumen microbiome. We hypothesize the calf is exposed to a microbial source prior to birth, and that the amnion plays an essential role in inoculation prepartum. Our objective was to isolate and identify microbes of the amniotic fluid and vaginal canal during late gestation and compare these populations to rumen fluid and meconium of newborn calves. Vaginal (VAG) and amniotic fluid (AF) samples were obtained from multiparous beef cows (n = 10) 10 days prior to their expected calving date. Rumen fluid (RF) and meconium (MEC) samples were obtained from each newborn calf immediately following parturition. Microbial DNA was isolated and purified utilizing the QIAmp DNA Stool Minikit (Qiagen) for amplicon 16S rRNA sequencing. All analysis was performed in QIIME2. Alpha-diversity was not different between MEC and AF (q ≥ 0.09) under any metric, but MEC and VAG differed under Faith’s Phylogenetic Diversity (q = 0.03). The MEC, AF, and VAG all differed in beta-diversity (q = 0.003). The degree of similarity between AF and MEC may indicate the AF plays a crucial role in the colonization of the fetal gut prepartum. Each of these lines of evidence outline fundamental aspects of the unfolding amnion-fetal gut-microbial axis, and provide key targets for future research into rumen development and the manipulation of feed efficiency in beef calves.