bluuebunny/crossref_metadata_2025 huggingface dataset:
PSIV-1 Concentrations of follicle stimulating hormone and progesterone in female offspring born to ewes poorly fed during gestation
Authors: Kuhl Ariel A , Tillquist Nicole M , Reiter Amanda S , Kawaida Mia Y , Dougherty Morgan M , Barnello Nicholas M , Reed Sarah A , Govoni Kristen E , Zinn Steven A
Published: September 2024

The objective of this study was to determine the effects of poor maternal nutrition (restricted- and over-feeding) during gestation on the reproductive efficiency of female offspring. We hypothesized that ewes born to restricted- and over-fed dams would have reduced fertility and decreased concentrations of follicle stimulating hormone (FSH) and progesterone (P4). Multiparous Dorset ewes (F0; n = 46) were fed one of three diets from d 30 of gestation until parturition according to NRC requirements for total digestible nutrients: control- (100%), restricted- (60%), or over- (140%) fed. Resulting female offspring (F1; n = 38) were raised on a control diet and are identified as CON (n = 10), RES (n = 12), or OVER (n = 16) corresponding to diets of their dam. Between 16 and 19 mo of age, the F1 ewes were estrous synchronized by vaginal insertion of a controlled intravaginal drug release device (CIDR) for a 12-d period, followed by a 2 mL (5 mg/mL) intramuscular injection of prostaglandin F2α, and then bred to one of two related rams. Day 0 of gestation was considered when a raddle mark was observed on the rump of the ewe. Time to pregnancy was calculated as the number of days from when the ewes were initially housed with the ram until d 0 of gestation. Based on ultrasounds on d 37 ± 0.77 of gestation, all F1 ewes were identified as pregnant on first service and number of fetuses was recorded and lambs born were counted at parturition. Data were analyzed using RStudio with a significance of P ≤ 0.05 and a tendency of 0.05 < P ≤ 0.10. Maternal diet did not significantly affect time to pregnancy, number of fetuses, or number of lambs born (P ≥ 0.13). Blood samples (10 mL) were collected via jugular venipuncture at four timepoints (d -14, -7, 0, 7) corresponding to d 0 of gestation and were analyzed for concentrations of FSH and P4 by enzyme-linked immunoassays in 29 ewes (CON: n = 8, RES: n = 8, OVER: n = 13). The CON ewes had 15.2% less FSH than OVER ewes (P = 0.05) and RES ewes tended to have 14.2% less FSH than OVER ewes (P = 0.08). Concentrations of P4 were not different in F1 ewes (P ≥ 0.14). However, concentrations of P4 in F1 ewes tended to increase (P = 0.08) by 12% from d -14 to d 0, which corresponds with a normal estrous cycle. The increased concentration of FSH in OVER ewes could be due to a dysregulation of FSH. However, those effects may be mitigated at some point in time later in gestation since there were no differences in time to pregnancy nor number of lambs born.
PSIV-5 Prioritizing candidate genes for seminal traits and residual feed intake in cattle: Integrating QTLome Analysis and RNAseq Datasets
Authors: Garcia Emmanuel , Jahuey-Martínez Francisco Joel , Carrasco V Julissa , Martinez-Quintana Jose A A , Rodríguez-Almeida Felipe A
Published: September 2024

The QTLome represents the collection of QTLs (quantitative trait loci) documented for each trait within a specific species, detailing the position, effect, and mode of inheritance of each locus. Despite the abundance of known QTLs for productive traits in cattle, only a few genes have been identified as selection markers. This study aimed to prioritize genes within validated QTLs associated with crucial traits in cattle by integrating this information with RNAseq data. Initially, bovine QTLs (n = 161,730) were sourced from the AnimalQTLdb database (version 44), and both graphical and quantitative analyses were conducted using R software. Only annotations within the UMD 3.1 genome were considered, with overlapping QTLs from the same scientific report grouped together. Following quality control measures, the number of QTLs was reduced to 37,146. Validated QTLs were determined by identifying overlapping annotations from various studies or those within a distance of < 1 Mb for the same phenotypic trait, resulting in a total of 3,856 validated QTLs. For gene prioritization, validated QTLs were selected based on semen traits and residual feed intake (RFI). Transcriptomes corresponding to these traits were sourced from NCBI (PRJNA516089 and PRJEB7696). Sequence filtering was performed using the fastp program, and transcript counts were obtained with SALMON software. Sequences were aligned to the Ensembl UMD 3.1 reference genome (version 94), and differential expression analysis was conducted using the R package DESeq2, considering only the group factor (high/low) for each trait (fertility/RFI). Integration of QTLs and transcriptomes utilized the methodology of the cageminer R package, which prioritizes candidate genes within validated QTLs, identifies those grouped in co-expression modules enriched by reference genes, and correlates with the study phenotype (biserial r > 0.2). Reference genes were obtained from Ignatieva et al. (2021 PMID 34290736) and Chen et al. (2021; PMID 33664767). Among the 18 validated QTLs for semen traits, four candidate genes (TSPAN6, QSER1, ADRB2, AKAP4) were identified. Except for ADRB2, these genes exhibited significant differential expression (P < 0.05) in contrasting groups of Holstein cattle. They are associated with semen traits and perform functions such as regulation of spermatogenesis, development, activation, and cell growth. Regarding RFI, 127 validated QTLs yielded 205 prioritized genes, of which 123 showed significant differential expression (P < 0.05) in divergent groups of the Nelore breed. These genes are involved in the immune response and the polymerization and organization of actin filaments, processes that have been reported as biologically relevant to RFI. The implemented strategy was efficient for gene prioritization through the integration of QTLs and RNAseq.
PSV-23 Physiological status evolution of veal calves after reception period
Authors: Blanch Marta , Pastor Jose J
Published: September 2024

Veal calves have to deal with several stressors early in life, such as transport and commingling with animals of unknown health histories from multiple different origins; making the reception a possible critical period where animals should adapt to all these challenges. The aim of this study was to evaluate the evolution of the physiological status of veal calves after farm reception. Dairy beef calves [n = 84; body weight (BW) = 44.3 ± 3.05 kg, BVD-free] coming from auction market were followed during the 8 wk after farm arrival. On farm arrival animals were housed individually until d 39 when animals were grouped in pens of 4 calves. Animals (n = 24) were blood sampled on d 1 (day of arrival), on d 7, on d 37, and on d 41 (48 h before and after grouping animal) to analyze biomarkers related to immune system (MILLIPLEX MAP Kit), energy status (BHBA) and gut integrity (citrulline, lactulose and mannitol). Data were analyzed by unpaired t-test (normally distributed data) or by non-parametric Mann-Whitney test (data not normally distributed). After the first week of adaptation (d 7 vs d 1), animals showed a general activation of the immune system increasing serum concentration of interleukin (IL) 8 (P < 0.001), interferon (INF) γ (P < 0.001), tumor necrosis factor (TNF) α (P < 0.01), IL10 (P < 0.001), macrophage Inflammatory Protein (MIP) 1α (P < 0.05), IP10 (P < 0.001), monocyte chemoattractant protein (MCP) 1 (P < 0.01), and IL1β (P < 0.15). In parallel animals reduced the mobilization of fat, evidenced by a decrease in the concentration of BHBA (P < 0.001), and displayed changes in gut permeability reducing lactulose and mannitol concentrations (related to paracellular and transcellular transport, respectively; P < 0.001). On the other hand, after the grouping challenge on d 39 (comparing d 41 vs d 37), calves experienced a certain immunosuppression indicated by the reduction of IL10 (P < 0.001), IP10 (P < 0.01), MIP1β (P < 0.01), Vascular endothelial growth factor (VEGF) α (P < 0.05), and MCP1 (P < 0.15). Moreover, after the mixing challenge, animals tended to increase the mannitol concentration (P < 0.001) in serum. From this trial, we can conclude that the stress experienced by veal calves in situations like transport and/or mixing, has a direct impact on their immune system. The observed immunosuppression may increase their predisposition to experience health issues. Further research should be conducted in calves to develop strategies able to boost their immune system and increase their resilience in front of the challenges occurring wk 1 in a fattening farm.
PSV-24 Administering the maternal bovine appeasing substance before slaughter to improve carcass characteristics of finishing cattle
Authors: Cooke Reinaldo F , Kertz Nicholas C , Pickett Autumn , Mackey Shea
Published: September 2024

Two experiments evaluated carcass characteristics of finishing steers administered the maternal bovine appeasing substance (mBAS) prior to slaughter. In Exp. 1, Angus-influenced finishing steers (n = 954) housed in 6 original pens were used. Each original pen was split into a pair of experimental pens 14.3 d ± 3 d prior to slaughter, in a manner that number of steers and average pen body weight (BW) were similar. An oiler containing mBAS (Ferappease Finish Cattle 5%; FERA Diagnostics and Biologicals; College Station, TX) was added to one of the experimental pens 7 d prior to slaughter (n = 6), whereas the other pen did not contain an oiler (CON; n = 6). The oiler was designed to deliver 120 mL of mBAS/steer during a 7-d period. Steer BW was recorded 7 d prior to and during loading (final BW) to the packing plant. No treatment effects were detected (P ≥ 0.51) for BW gain, final BW, and proportion of carcasses that graded Choice or Prime. Carcass dressing was greater (P = 0.02) in mBAS compared with CON steers (65.9 vs. 64.2%; SEM = 0.5), which was not sufficient to impact hot carcass weight (HCW; P = 0.29). Incidence of dark-cutting carcasses did not differ between treatments (P = 0.23), despite being decreased by 3-fold in mBAS steers. In Exp. 2, Angus-influenced finishing steers (n = 80) housed in 16 pens (5 steers/pen) were used. Pens were arranged in 4 rows of 4 pens/row, and rows were alternately assigned to receive an oiler containing mBAS (n = 8) or mineral oil (CON+; n = 8) 7 d prior to slaughter. Oilers were designed to deliver 120 mL/steer of mBAS or mineral oil during the 7-d period. Steer BW was recorded as in Exp. 1, and a blood sample was collected during exsanguination. No treatment effects were detected (P ≥ 0.20) for BW parameters, carcass marbling score, backfat thickness, longissimus muscle area, yield grade, and proportion of carcasses that graded Choice or Prime. Carcass dressing was greater (P = 0.02) in mBAS steers compared with CON+ (60.6 vs. 59.6%; SEM = 0.3) but HCW did not differ (P = 0.47) between treatments. Plasma cortisol concentration was less (P < 0.01) in mBAS steers compared with CON+ (11.7 vs. 20.8 ng/mL; SEM = 1.6). Incidence of dark-cutting carcasses did not differ (P = 0.53) between treatments, despite a 2-fold decrease in mBAS steers. In summary, mBAS administration to finishing cattle using oilers during the last 7 d on feed alleviated the stress elicited by the process of slaughter, which resulted in increased carcass dressing.
PSVI-23 Economic potential of field peas as an alternative to corn distillers dried grain with solubles (DDGS) in beef heifer growing diets
Authors: Undi Michael , Biermacher Jon T , Sedivec Kevin K , Long Timothy
Published: September 2024

Field pea production in North Dakota has increased significantly over the past 20 yr with hectares planted increasing by more than 68% over that period. With the increase in supply of field peas, there is interest in evaluating whether using field peas in beef cattle finishing rations is economical compared with commonly used ingredients such as corn DDGS. This 2-yr study was conducted to a) determine the economic potential of field peas relative to corn DDGS in growing heifer diets, and b) identify price points for competitive utilization of field peas as an alternative to corn DDGS in growing heifer diets. Each year, 162 heifers were kept in six dry lot pens and fed isocaloric and isonitrogenous corn DDGS-based or field pea-based total mixed rations in the fall and winter. Heifer performance data analysis considered the fixed effects of diet (corn DDGS or field peas), season (fall and winter), and diet x season interaction. Economic evaluation of feed costs for each total mixed ration (TMR) was based on the 2-yr average measures of dry matter intake (DMI) and total body weight (BW) gain. Sensitivity analysis was conducted to calculate relative total cost of feeding field peas versus corn DDGS for a number of combinations of prices of corn DDGS and field peas. Heifer final BW, total BW gain, and daily BW gains (ADG) were not impacted (P > 0.05) by diet when 0.33 kgּ d-1 and 0.48 kgּ d-1 of corn DDGS and field peas were incorporated into corn DDGS-based and field peas-based TMR, respectively. Seasonal differences in heifer performance showed greater (P < 0.001) DMI in winter relative to fall and greater (P < 0.001) total BW gain and ADG in the fall relative to winter. The relative value of field peas was mainly driven by amount of field peas incorporated into diets and price of field peas relative to corn DDGS. Overall, for a base-case average price of $325 MT-1 for corn DDGS, the breakeven price for field peas was equal to $231.15 MT-1, which was 36.8% less than the base-case price of $366 MT-1 for field peas, and 71% of the base-case price of corn DDGS. Conversely, for the base-case price of field peas of $366, the breakeven price of corn DDGS was equal to $514.60 MT-1, which was 58.3% more than the base-case price of $325 MT for corn DDGS and 140.6% more than the base-case price for field peas. Results show that there are economic benefits of including field peas in cattle rations when there is excess field peas production available at competitive prices and offer useful economic information to the field pea processing industry about the range of prices that beef cattle producers can afford to pay for field peas relative to corn DDGS.
PSIX-1 Evaluation of canola meal inclusion in adult dog diets and the impact on digestibility, stool quality, and palatability
Authors: Gajda Angela M , Daristotle Leighann , Frantz Nolan
Published: September 2024

Canola meal is a commonly used ingredient in livestock, fish, and poultry feed and is also AAFCO (Association of American Feed Control Officials) approved for use in pet food. This study’s objectives were to evaluate the impact of canola meal inclusion on nutrient digestibility, stool quality, and palatability in adult dogs. Canola meal was included at 5% or 10%, substituting pea protein, in a high-protein, chicken-based adult maintenance canine diet to maintain similar protein, fat, and crude fiber. The study was approved and followed by the facility’s Institutional Animal Care and Use Committee. A standard 2-bowl palatability test over a 2-d period was executed (n = 30 each) to determine intake ratio (IR) between test diets (5% and 10% canola meal), and versus control. Total tract nutrient digestibility was evaluated (n = 8 per diet) with 5 d of diet acclimation followed by 5 d of total fecal collection. Stool quality was evaluated on a 1 to 5 scale, where 1= nonformed/ diarrhea and 5 = hard formed. Digestibility data were analyzed by ANOVA with Treatment (% Canola Meal) as fixed effect, and stool quality, by linear mixed effects model with Day and Treatment (% Canola Meal) as fixed effects and Dog as random effect (R version 4.2.2). With P < 0.05 considered statistically significant, no differences were observed between diets for protein digestibility (all > 84% avg), fat digestibility (all >92% avg), or stool scores (all averages between 3.4 to 3.5). Canola-containing diets were equally palatable as the control (IR = 58:42, 5% canola meal vs. control; 57:43, 10% canola meal vs. control), but 10% was preferred vs. 5% (75:25; P < 0.05). Overall, digestibility, stool quality, and palatability were not impacted by canola meal up to 10% inclusion, suggesting that it is an acceptable ingredient for dog diets.
PSVIII-17 A comparison of a monoculture barley crop to a barley-based complex mixture on forage yield, quality, dry matter intake, enteric methane emissions and growth performance of pregnant yearling heifers
Authors: Schreiner Brittany , Ribeiro Gabriel O , Lardner H (Bart) A , Penner Gregory B
Published: September 2024

The objective of the study was to compare forage yield and composition, dry matter intake (DMI), growth, and enteric methane emissions for heifers grazing a barley monoculture (MON) or a barley-based complex forage blend (COM). The 2-year study was conducted near Saint Brieux (SK, Canada) and evaluated 2 treatments with 4 paddocksּ treatment-1ּ yr-1. Treatments included MON (CDC Rosser) seeded at 123 kg/ha or a COM which contained barley seeded at 61.5 kg/ha and a mixture of species seeded at 12.3 kg/ha. The COM mixture included 54% millet (Proso and Japanese), 14% Italian ryegrass, 13.5% clover (Berseem, Persian, Crimson), 4.5% hairy vetch, 4.5% black oil sunflower, 3% forage collards, 3% turnips, 2% phacelia, and 1% chicory. Forages were seeded in alternating strips (0.4 ha) to create individual paddocks. Pregnant yearling heifers (n = 80/yr) were weighed on 2 consecutive days at the start and end of the study, randomly allocated based on BW to each treatment, and assigned to a paddock (10 heifers/paddock). Heifers were provided fresh forage daily. Grazing was initiated at the late milk stage for MON and continued until the hard dough stage of maturity. Paddocks were then swathed, and grazing continued resulting in 84 and 77 d in yr 1 and 2, respectively. Forage samples and residual forage were collected weekly to estimate forage yield, composition, and intake. Rib and rump fat measurements were taken at the start and end of the study. Methane emissions were measured using the sulfur hexafluoride (SF6) tracer gas technique over a 4-d period while grazing both standing and swathed crops in each year. Forage yield [dry matter (DM) basis] did not differ among treatments (P = 0.59) during the growing season averaging 5.6 t/ha and did not differ (P = 0.57) once swathed averaging 5.7 t/ha. Treatment and date of sampling affected (P < 0.01) the proportion of barley, with barley representing 95% of the DM for MON and 81% for COM. Chemical composition did not differ among treatments for OM, CP, NDF, lignin, and starch; however, DM tended (P = 0.08) to be less for COM, and ADF and WSC were greater (P = 0.01 and P = 0.02) for COM than MON. Dry matter intake (DMI) was not affected while grazing standing (P = 0.98) or swathed (P = 0.50) forages with mean values of 8.8 and 10.2 kg/d, respectively. Rib and rump fat did not differ, but average daily gain was 0.1 kg/d greater (P < 0.01) for COM than MON. As a result, gain:feed was 0.08 kg/kg greater for heifers grazing COM (P < 0.01) than MON. Enteric methane emissions did not differ for treatment when heifers were grazing standing (P = 0.77) or swathed (P ≥ 0.99) forages. Growing an annual complex forage mixture rather than a monoculture crop may improve growth of yearling heifers, but does not affect forage yield, DMI, or enteric methane production.
PSVIII-3 The functional properties and digestibility of round and wrinkled pea flour in swine diets
Authors: Bentley Bria E , Columbus Daniel A , Beaulieu A Denise
Published: September 2024

Wrinkled and round pea flour display physical and compositional differences. Wrinkled peas have reduced activity of the starch branching enzyme, which decreases amylopectin production. As a result, wrinkled peas have an increased proportion of amylose, relative to round peas. The rate and extent of starch digestion are influenced by the ratio of amylose to amylopectin in starch. Extrusion results in swelling of the starch, altering the crystalline structure. The objective of this study was to determine the role of the amylose to amylopectin ratio and extrusion on starch digestibility and microbial characteristics in growing pigs. Ileal-cannulated barrows (n = 8) with an initial body weight (BW) of 40 ± 1 kg were randomly assigned to 1 of 4 dietary treatments (n = 8 pigs/treatment) in a replicated Latin square design with four blocks. Dietary treatments were round pea flour (RPF), extruded round pea flour (RPF-E), wrinkled pea flour (WPF), and extruded wrinkled pea flour (WPF-E). The starch content decreased in the native WPF (36.7%) and WPF-E (34.7%) compared with RPF (50.1%) and RPF-E (49.1%). However, the amylose content in native WPF (77.1%) and WPF-E (70.7%) was greater compared with RPF (40.1%) and RPF-E (39.8%). Ileal digestibility of starch differed between pea flours (P < 0.05), greatest for RPF (92.8%) and RPF-E (92.2%) and least for WPF (80.2%) and WPF-E (76.7%). Total tract digestibility was least for RPF (98.7%) compared with other treatments (P < 0.05). Total tract digestibility of starch was greatest with RPF-E compared with RPF (99.5% vs 98.7%, P < 0.01) but was not different from WPF (99.25%) or WPF-E (99.51%). Shannon index, an indicator of microbial diversity, decreased in ileal digesta of WPF-E-fed pigs compared with RPF-E (P < 0.05) but similar among treatments in the feces. In summary, compared with WPF or WPF-E, RPF and RPF-E had reduced amylose content and greater starch digestibility determined at the end of the ileum; however, total tract digestibility of starch was similar among all treatments. Furthermore, RPF-E compared with RPF, WPF, and WPF-E increased microbial diversity in the ileal digesta, but no difference among treatments in the feces.
PSVIII-4 Physiochemical and nutrient profile study: Effect of oat varieties and types (feed type vs. milling type)
Authors: Deng Ganqi , Christensen David , Lardner H (Bart) A , Yu Peiqiang
Published: September 2024

The objective of this project was to assess the impact of four oat varieties and types (feed type vs. milling type) on their physiochemical and nutrient profiles. Four oat varieties (Haymaker, Nasser, Arborg, and Summit) from 3 harvested yr (2018, 2019, 2020) were used for chemical analysis, energy profiles and protein and carbohydrate subfractions evaluations following the AOAC standard methods, NRC-2001 model, and CNCPS 6.5 model, respectively. The experiment design was a randomized compete block design with oat varieties as a fixed effect and harvested year as a random block effect. The MIXED model of SAS 9.4 was used for statistical analysis with significant level declared at P < 0.05 and trends at 0.05 ≤ P < 0.1, and SAS contrasts were used for comparing oat types (feed type vs. milling type). Results showed that Nasser oat had the greatest ether extract (EE), and non-protein nitrogen (NPN) value of the four varieties [4.05, and 3.74 % dry matter (DM); P < 0.01] while the value of crude protein (CP) of Nasser oat was least but had a similar CP content with Arborg and Summit oat (14.69, 15.78, and 15.40 % DM). Haymaker oat had the greatest CP content among the four varieties (17.57 % DM, P < 0.05). Arborg, Summit and Haymaker oat had similar acid detergent lignin (ADL) in the four oat varieties (3.60, 3.29, and 4.19 %DM), yet had greater ADL content compared with Nasser oat (1.63 % DM, P < 0.01). More importantly, Haymaker oat had greater indigestible neutral detergent fiber at 120 h (iNDF120h, % DM) compared with Summit oat (P < 0.05) and had similar iNDF120h content with Arborg and Nasser oat. There was a significant difference in EE, total carbohydrate (C HO), and ADL values between feed type and milling type (P < 0.05). Haymaker oat had the greatest truly digestible crude protein (tdCP) among the four oat varieties (17.42 % DM, P < 0.05). Nasser oat also had the greatest total digestible nutrients (TDN) and all energy values compared with other three oat varieties (P < 0.05), while Arborg and Summit oat had similar tdCP, TDNs and energy values. In addition, Haymaker oat had greater PA2 (6.62 vs. 5.37 % DM) and PB1 (10.18 vs. 8.72 % DM) than that of Nasser (P < 0.05) although they were the same oat types, and the indigestible fiber fractions (CC) of Nasser oat was least among these four varieties (5.04 %CHO or 3.93 % DM, P < 0.05). Haymaker also had greater RDPA2, RDPB1, total RDP, RUPA2, RUPB1, total RUP fractions than that of Nasser oat (P < 0.05). Feed type had relatively greater CP, greater energy values but with less total CHO contents than milling oat. In conclusion, Nasser oat could be an important source of grain to replace barley in the ration of dairy cattle.
PSVIII-8 The impact of foliar fungicide application on barley silage fermentation characteristics and performance of lactating dairy cows
Authors: James Christina S , Penner Gregory B , Beattie Aaron D , Christensen David , Mutsvangwa Timothy
Published: September 2024

Forages are an important component in dairy cow diets and barley silage is the primary forage source in western Canada and parts of the USA. Foliar fungal diseases can infect barley, thereby causing leaf damage and a loss of yield and quality. The objectives were to determine the effects of foliar fungicide application on two barley forage varieties, one resistant (CDC Fraser) and the other susceptible (Claymore) to foliar fungal disease, on silage ensiling characteristics and feed intake, milk production and composition, ruminal pH, and nitrogen (N) balance in dairy cows. Multiparous Holstein cows [n = 12; mean (ays in milk (DIM) = 40 ± 17; mean body weight (BW) = 720 ± 26 kg] at the start of the experiment) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of dietary treatments. Experimental periods were 25 d, with 18 d of dietary adaptation and 7 d of sample and data collection. Test diets were: 1) fungicide-treated Claymore silage (CF); 2) untreated Claymore silage (CNF); 3) fungicide-treated CDC Fraser silage (FF); and 4) untreated CDC Fraser silage (FNF) as the major source of forage. Forage yields were 1.86 (FNF), 1.46 (CNF), 1.17 (FF), and 1.35 (CF) t dry matter (DM)/ha, likely reflective of the low rainfall during the growing season. Experimental silages were similar in crude protein (mean = 14.0%; DM basis), ammonia (mean = 1.95%), and total volatile fatty acid (mean = 9.25%) concentrations. CDC Fraser silage had greater lactic acid concentration (P < 0.001) but decreased pH (P = 0.01) and acetic acid concentration (P < 0.01) than Claymore silage. Silage aNDF contents (DM %) were similar in FF and FNF, but greater in CNF than CF (interaction; P < 0.05). Without fungicide application, barley variety had no effect on silage starch content (DM %), whereas with fungicide application, Claymore had a greater silage starch content than CDC Fraser (interaction; P < 0.05). Dry matter intake, milk yield, and milk composition were unaffected by diet (P > 0.05). Total tract nutrient digestibility was unaffected by diet (P > 0.05). Intake of N, and urinary and fecal N excretion, total N excretion, milk N, and apparent N balance (expressed as g/d or % of N intake) were unaffected by diet (P > 0.05). Ruminal short-chain fatty acid (SCFA) concentrations and pH were unaffected by diet (P > 0.05); however, total SCFA concentration was similar in CF and CNF but was greater in FNF than FF (interaction; P < 0.05). Valerate concentration was similar in FF and FNF but greater in CF than CNF (interaction; P < 0.05). Foliar fungicide application on barley, regardless of variety susceptibility to fungal diseases, did not negatively affect silage quality or dairy cow performance.
PSVIII-13 A comparison of biochar and activated charcoal as feed additives to prevent boar taint
Authors: Parent Melissa , Bone Christine , Squires E James
Published: September 2024

Boar taint is a urine or feces-like odor that occurs when meat from entire male pigs is heated and is caused primarily by the deposition of androstenone in the fat. Androstenone is thought to circulate in the body similarly to sex steroids; this may facilitate the recirculation of androstenone to the liver or systemic circulation for deposition in the fat. Previous studies from our lab concluded that feeding activated charcoal (AC) can reduce the accumulation of androstenone in fat. However, this is not a practical solution as AC is expensive and not approved for use in livestock feed. Biochar is a charcoal-based adsorbent that is approved as a feed additive and has similar physical binding properties to AC, such as high porosity and large surface area. Our in vitro binding studies showed similar binding efficiency between AC and biochar for androstenone; however, the efficacy of biochar for reducing boar taint has not been assessed in vivo. Therefore, the objective of this study was to compare the efficacy of biochar and AC as dietary treatments for reducing fat androstenone concentrations. Beginning at 71.3 ± 1.3 kg, [(Yorkshire x Landrace) x Duroc] boars (n = 34) were acclimated to a standard corn and soybean meal-based finisher diet, for 1 wk. Animals were then randomly assigned to a finisher diet containing 5% AC (n = 17) or 5% biochar (n = 17) for 4 wk, followed by a 2-wk recovery period on the standard finisher diet. Backfat biopsies were performed bi-weekly and fat androstenone concentrations were quantified using an androstenone-specific enzyme-linked immunosorbent assay. All animals were evaluated on the change in fat androstenone concentrations quantified at the end of the treatment and recovery period. Boars with increased fat androstenone concentrations at the end of recovery were classified as having a positive response to the treatment. Statistical analysis was performed using a Student’s t-test to evaluate differences in fat androstenone concentrations between the end of treatment and recovery periods in animals with positive treatment responses. Fat androstenone concentrations at the end of treatment were 1.721 ± 0.152 μg/mL and 1.431 ± 0.412 μg/mL for AC (n = 9) and biochar (n = 6), respectively; these values significantly increased to 5.475 ± 0.804 μg/mL (P = 0.0003) for AC and 3.924 ± 0.586 μg/mL (P = 0.004) for biochar at the end of recovery. Moreover, concentrations of androstenone in the fat at the end of treatment and recovery were similar between AC and biochar treatments. These findings demonstrate that biochar can decrease fat androstenone concentrations in some mature boars, with comparable efficacy to that of AC. However, additional work is needed to identify biomarkers associated with positive treatment responses so that biochar can be provided in a targeted manner to boars that will respond favorably.
PSVIII-14 The significance of colostrum quality on feed efficiency in Canadian Holstein calves
Authors: Phillips Avalon G R , Jahnel Ricarda E , Lynch Colin , Makanjuola Bayode O , Miglior Filippo , Schenkel Flávio S , Baes Christine F
Published: September 2024

For a more sustainable dairy industry it is crucial to select for feed-efficient cattle. Although feed efficiency research has primarily focused on lactating animals, genetic selection for feed efficiency in calves has continued to gain research interest. Previously estimated genetic parameters for pre-weaned calf feed efficiency suggest residual metabolizable energy intake (RMEI) as a potential trait for selection. However, the trait definition of RMEI needs further evaluation. In previous studies only the intake of colostrum, fed in the first hours of the lif of a calf, was included to define RMEI. The inclusion of colostrum quality ([grams of immunoglobulin (g IgG)] might better represent the transfer of passive immunity to calves and enhance the indicator trait for feed efficiency. Therefore, the objective of this study was to evaluate the impact of colostrum characteristics on estimating RMEI as a measure of calf feed efficiency in Canadian Holstein calves. Records from 330 pre-weaned Canadian Holstein calves between 0 and 65 d of age, born between 2016 and 2021 were provided by The Ontario Dairy Research Centre (Elora, ON, Canada). Data included calf health (incidence of scours, 1 = event, 2 = no event), feed intake (kg), body weight (BW; kg), and colostrum quality (g IgG) ranging between 17.41 and 151.69 g IgG. RMEI was estimated by four linear regression models using metabolizable energy intake (MEI) for two time periods (RMEI1 = first month of age calves, RMEI2 = second month of age calves) according to previous studies. For both time periods, colostrum quality was then included in the linear regression model, in addition to scours incidence, year and season, trial, and regression on average daily gain and metabolic BW to estimate RMEI corrected for colostrum quality (i.e., RMEIc1 and RMEIc2). Colostrum quality was fitted as a fixed effect with four classes (≤72 g IgG, 73-76 g IgG, 77-96 g IgG, ≥97 g IgG), divided according to the quartiles of its distribution. The inclusion of colostrum quality had a significant effect on MEI in the first month of age (P ± 0.001) and a trend for significance in the second month of age (P = 0.095). RMEIc model had an adjusted R2 value of 0.86 with the inclusion of colostrum quality in the first time-period. As a next step, genetic parameters need to be estimated to determine any possible gain using RMEIc over RMEI. Improving the definition of RMEI will further the potential to select for feed efficiency in younger animals to achieve sustainability goals.
PSVIII-23 Attenuation of oxidative stress and inflammatory response improves gut integrity in piglets after infection
Authors: Jin Shunshun , Xu Haoxiang , Gong Joshua , Yang Chengbo , O Karmin
Published: September 2024

Enterotoxigenic Escherichia coli (ETEC) is a primary cause of post-weaning diarrhea in piglets, leading to serious health issues and economic loss in the swine industry. Increased oxidative stress and inflammation have detrimental effects on gut health. The present study aimed to investigate the regulation of oxidative stress and inflammatory response in a piglet model challenged with ETEC and to evaluate whether the chosen probiotic could improve intestinal function in piglets. A total of 24 weaned piglets susceptible to ETEC F4 infection were randomly divided into four groups: Group 1 (control), Group 2 (E. coli infection), Group 3 (E. coli infection received antibiotic avilamycin), and Group 4 (E. coli infection received B. licheniformis HG76). Group 2, Group 3 and Group 4 were infected with E. coli by an oral gavage of ETEC F4 (5 mL, 1 × 106 CFU/mL). Five days after infection, piglets in all groups were euthanized. The blood and intestine samples (a mid-jejunum segment) were collected, and serum was prepared. ETEC infection significantly increased serum and jejunal malondialdehyde (MDA) concentrations and serum diamine oxidase (DAO) activity (P < 0.05). ETEC infection also significantly decreased tight-junction proteins (ZO1, occludin), superoxide dismutase-1 (SOD), and heme oxygenase-1 (HO-1) expression (P < 0.05). Furthermore, ETEC infection significantly increased the expression of pro-inflammatory cytokines [interlueken (IL) -6, tumor necrosis factor (TNF) -α] in the intestine (P < 0.05). Antibiotic or probiotic supplementation mitigated oxidative stress and inflammation, as evidenced by decreased oxidative stress biomarkers, increased expression of antioxidant enzymes (SOD, HO-1) and downregulated the expression of proinflammatory cytokines (IL-6, TNF-α; P < 0.05). Antibiotic or probiotic supplementation also improved intestinal integrity, as demonstrated by decreased DAO activity and increased tight-junction proteins expression (P < 0.05). These results suggest that attenuation of oxidative stress and inflammatory response can improve piglet gut integrity after ETEC infection.
PSX-11 Behavior of Kentucky beef producers towards controlling internal parasites
Authors: Coffey David , Lee Amanda L , Arnold Michelle , Lehmkuhler Jeffrey W
Published: September 2024

Internal parasites can reduce production efficiency in livestock grazing systems. Increased concern has been expressed regarding the potential loss of efficacy of available products currently available to livestock managers to control internal parasites. A survey was conducted during the spring of 2023 of Kentucky beef producers participating in a Fecal Egg Count Reduction Test (FECRT) study to gain insight related to their behavior toward managing internal parasites. A total of 70 individuals completed or partially completed the survey instrument. Similar numbers of operations had a single calving season of either spring (35.8%) or fall (37.3%) with these being more prominent than having both spring and fall calving seasons or a year-round calving season. When asked if they had ever performed a FECRT within their herd previously, 96.9% of respondents indicated they had not. Administering an anthelmintic twice annually was reported most often at 69.2%, while 16.9% indicated once per year and more than twice annually being reported by only 6.2%. Sixty percent of beef cattle managers indicated that they rotated products. When asked about the frequency of product rotation, 33.9% indicated they rotated products at each application while 25.8% switched products annually with another 21% never switching products. It is unclear as to why these two questions yielded slightly different outcomes. As all anthelmintics dosage is based on body weight (BW), determination of dosage was asked. More than 75% estimated BW for dosage while 15.4% used a scale to set the dosage for each animal and 7.7% used a scale to obtain an average BW to set the dosage for all animals. Route of administration of product most frequently utilized was pour-on at 66.3% either alone or in combination with another product. Oral drench (17.5%) and injectable (13.8%) were the next most common routes of administration with a single report of product being provided in the feed. This information provides Extension educators with insight regarding beef cattle managers’ behaviors towards anthelmintic use and aid in developing educational programs focused on controlling internal parasites.
PSXII-6 Canopy height as a predictor of forage biomass in native rangelands and bermudagrass pastures
Authors: Congio Guilhermo F S , Hale Taner , James Thomas , Araujo Eloa M , Sparks Maira , Chi Myoung-Hwan , Maciel Isabella C F
Published: September 2024

Accurate and less laborious estimates of forage biomass are needed for research and management decisions in grazing lands. Our objective was to develop linear regressions to estimate forage biomass using canopy height in both native rangelands and introduced bermudagrass [Cynodon dactylon (L.) Pers.] pastures in the Cross Timbers and Southern Tallgrass Prairie Ecoregion. Twelve pastures averaging 26 acres each were equally distributed in two ranches located in the Love County, Southern Oklahoma. The native rangelands comprise native tall- and mid-grasses along with forbs and some woody shrub species. Little bluestem [Schizachyrium scoparium (Michx.) Nash] is the dominant species, with brome (Bromus L.), broomsedge bluestem (Andropogon virginicus L.), ragweed (Ambrosia psilostachya DC.), purpletop tridens [Tridens flavus (L.) Hitchc.), dropseed (Sporobolus R. Br.), and Indiangrass [Sorghastrum nutans (L.) Nash] commonly found. The introduced pastures are dominated by bermudagrass with cereal rye (Secale cereale L.) and horseweed [Conyza canadensis (L.) Cronquist] commonly found as well. Samples occurred at pre- and post-grazing conditions from summer 2022 to fall 2023. Measurements included canopy height and hand-clipping all herbaceous vegetation in a 0.25-m2 frame. Forage samples were fresh weighed then dried for 72 h at 60°C and reweighed. There were 760 and 786 samples collected at native and introduced pastures, respectively. Data were analyzed using PROC GLM of SAS (SAS Inst., Cary, NC) including canopy height (cm) and forage biomass [kg of dry matter (DM)/ha] as independent and dependent variables, respectively. Only regressions including all parameters as significant (P < 0.05) were selected, and coefficient of determination (R2) and root mean square error (RMSE) were used to evaluate the predictive ability of the regressions. There was a pasture type (native or introduced) × season interaction (P < 0.001). This interaction is likely explained by the dominant species in each pasture type across seasons as well as their phenological stage. For the native rangeland, the spring linear regression including the quadratic term had the best fit with the greatest R2 (0.56) and the least RMSE (944 kg DM/ha; Table 1). Summer and fall regressions had R2 of 0.45 and 0.24 and RMSE of 1139 and 1343, respectively. No regressions were selected for winter because parameters were not significant (P = 0.53 and P = 0.18). For the introduced bermudagrass pasture, regressions presented R2 ranging from 0.24 and 0.30 except during the winter (R2 = 0.09). These results indicate that forage biomass can be acceptably estimated using canopy height only during spring in the native rangeland.
PSXII-3 Amino acid profile of warm-season perennial grass-legume mixed pasture continuously stocked by horses
Authors: Vasco Carol , Santos Erick , Dubeux José C B , Wallau Marcelo , Sollenberger Lynn , Warren Lori K , Wickens Carissa
Published: September 2024

Providing an ideal amino acid profile to horses improves nitrogen (N) utilization and reduces N excretion. This 2-yr study investigated protein concentration and amino acid profile of forages during 84 d of continuous stocking of mixed pastures of rhizoma peanut (RP; Arachis glabrataBenth) and bahiagrass (BG; Paspalum notatumFlüggé) receiving 30 kg N/ha (RP-BG) compared with BG pastures fertilized with 120 kg N/ha (BG-N) or with no nitrogen fertilizer (BG-U). Forage samples were collected on d 0, 14, 28, 42, 56, 70, and 84. All data were reported as percent of crude protein on a dry matter basis. Histidine and phenylalanine were affected by an interaction between pasture and day (P = 0.023 and P = 0.044, respectively). Mixed pastures resulted in greater histidine than BG-N at d 56 (P = 0.016) and 70 (P = 0.002) and greater than BG-U at d 70 (P = 0.005). Phenylalanine did not present any clear pattern and was similar across pastures throughout most of the grazing season. RP-BG provided greater lysine (P < 0.01) than monoculture pastures (6.24 vs. 6.00), and arginine was greater (P = 0.007) in RP-BG than BG-U (5.24 vs. 5.12). RP-BG, however, resulted in lesser threonine (P = 0.017) than BG-U (4.76 vs. 4.86) and lesser methionine (P = 0.016) than BG-N (1.89 vs. 1.94). Regardless of the fertilization level, monoculture bahiagrass had greater (P = 0.015) leucine than RP-BG (9.48 vs. 9.29). There was a day effect on arginine (P < 0.001), isoleucine (P < 0.001), leucine (P < 0.001), lysine (P = 0.009), methionine (P = 0.005) and threonine (P < 0.001). Concentrations of all amino acids varied throughout the grazing season, with most peaking at d 14 and returning to initial values late in the grazing season. Threonine, however, increased (P = 0.001) by 5.4% from d 28 to d 84 (4.67 vs. 4.92). Results of this study indicate that intercropping rhizoma peanut into bahiagrass pastures may reduce environmental impacts by reducing nitrogen fertilization needs and improves lysine concentration. Greater lysine in forages is beneficial as lysine is the first limiting amino acid in horse diets.
PSXIII-3 Regrowth interval and propionic acid effects on warm-season grass silage nutritive value and fermentation characteristics
Authors: Anderson Chadwade , Vendramini Joao M B , Moriel Philipe , Sollenberger Lynn , da silva Hiran , Garzon Jaime , Lazarin Joao V L , Sinisicalchi Debora , Miranda Andre
Published: September 2024

Warm-season perennial grass species are the main forages preserved as silage or haylage by livestock producers in Florida; however, the nutritive value and silage fermentation parameters are often less than desirable. The objective of this study was to investigate the effects of regrowth interval, propionic acid, and forage species on silage nutritive value and fermentation parameters. The study was conducted in Ona, FL in July and August 2021 and 2022. Treatments were the factorial combination of three forage species [Jiggs bermudagrass (Cynodon dactylon L.), ‘Camello’ brachiariagrass (Urochloa spp.), or Spain guineagrass (Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs)], two regrowth intervals (3 or 6 wk), and propionic acid [0.5% or 0 (control)], distributed in a randomized complete block design with 4 replicates. Forage was harvested and immediately packed into a mini-silo at a density of approximately 190 kg DM/m3. Camello and Spain had less DM (24 vs. 30%; P < 0.01), CP (8.0 vs. 10.7%; P < 0.01), but greater NDF (70 vs. 68%; P < 0.01), ADF (41 vs. 38%; P < 0.01), and in vitro digestible OM concentration (57 vs. 52%; P = 0.04) than Jiggs. There were no differences in fermentation characteristics among species. Forage harvested at 3-wk regrowth interval had less DM (24 vs. 29%; P < 0.01), NDF (68 vs. 71%; P < 0.01), ADF (38 vs. 40%; P < 0.01) but greater CP (10.8 vs. 8.3%; P < 0.01) and in vitro digestible OM (56 vs. 52%; P = 0.03) than 6 wk. There was no effect (P > 0.05) of regrowth interval on fermentation characteristics. Forage treated with propionic acid had greater DM (27 vs. 25%; P < 0.01), CP (9.6 vs. 9.0%; P < 0.01), lactic acid (4.3 vs. 3.1%; P < 0.01), and propionic acid concentrations (1.8 vs 0.1%; P < 0.01) but decreased pH (4.2 vs. 4.6; P < 0.01), ammonia (12 vs. 18% CP; P < 0.01), acetic acid (1.5 vs. 2.0%; P < 0.01), and butyric acid concentrations (0.2 vs. 1.5%; P < 0.01). Propionic acid affected bacterial population abundance by decreasing Clostridium (0.6 vs. 5.3%; P < 0.01) and Enterobacteria (3.0 vs. 11.1%; P < 0.01) and increasing Lactobacillus (45.0 vs. 32.7%; P = 0.04) and Bacillus (0.35 vs. 0.15%; P < 0.01). Forage species and regrowth interval were influential on silage nutritive value while propionic acid improved fermentation characteristics.
PSXIII-2 Does choice of apparatus affect detergent fiber fractions across forage types?
Authors: Sagastume Cecilia N , Espino Berman E , da Silva Aghata Elins Moreira , Hines Abbigail R , Smith W Brandon B
Published: September 2024

Since the 1960s, detergent fiber fractions have had a fundamental role in animal nutrition. Not only was this system an improvement on measurement of cell wall material, it has also helped advance our understanding and prediction of forage intake and digestibility. The ANKOM fiber analyzer, introduced in the 1990s, streamlined the assay, and multiple technical improvements have been introduced that increased the level of automation in the procedure. To date, however, there has not been an evaluation of the influence the choice of apparatus has on the results. The objective of this study was to determine the effect of fiber analyzer apparatus on recovery of detergent fiber fractions of various forage species. The study was designed as a randomized complete block design with a two-factor factorial treatment structure. The first treatment factor was fiber analyzer (ANKOM 200, ANKOM 2000, or ANKOM Delta), and the second treatment factor was forage (n = 12). Forages were ground to pass through a 1-mm screen and sealed in F57 fiber bags. All bags were subjected to neutral detergent fiber (NDF) and acid detergent fiber (ADF) assays according to manufacturer instructions in their designated fiber analyzer. After the ADF assay, samples were subjected to the acid detergent lignin (ADL) assay using the ANKOM DaisyII incubator. Data were analyzed using the GLIMMIX procedure of SAS 9.4. Across forage species, NDF concentrations were less (P = 0.02) from the manual ANKOM 200 (61.4%) than from ANKOM Delta or ANKOM 2000 (63.3 and 63.1%, respectively). Across forages, ADF was greatest (P < 0.01) from ANKOM 2000 (37.8%), followed by ANKOM Delta (36.2%), and least from ANKOM 200 (34.8%). However, these differences did not carry through as there was no effect of fiber analyzer on ADL concentrations (P = 0.67). Results are interpreted to mean that, across forage species, choice of fiber analyzer may have an influence on detergent fiber concentrations. However, these differences are minimized in the automated systems relative to the older, more manual apparatus.