bluuebunny/crossref_metadata_2025 huggingface dataset:
PSXI-5 Transforming retailer’s food waste into silage for sustainable animal nutrition
Authors: Rodriguez Vicky Garcia , Vandestroet Layton , Abeysekara Layton , Ominski Kim H , Bumunang Emmanuel , McAllister Tim A , Terry Stephanie A , Miranda-Romero Luis Alberto , Stanford Kim
Published: September 2024

Food waste (FW) represents a major environmental and socio-economic problem. In Canada, about 11.2 million metric tons of avoidable food waste is produced yearly. An alternative to reduce this impact would be preserving a greater proportion of this, for livestock feed. Therefore, the objective of this study was to use discarded fruits, vegetables, and bakery products from retailers (FW), ensile them, and assess their nutritional value and contribution to a sustainable livestock feed supply. For this, two treatments for reducing the moisture content of FW were evaluated: Sun-dried (SD), and Passive-dried (PD), were compared with Control (C), using laboratory mini-silos over 60 d of ensiling. Although dry matter (DM) increased by 1-5% for PD and SD, respectively, up to 41.9% of bread products were required to produce a targeted silage DM of 38%. Silage aerobic stability was assessed during 20 d exposure to air. Chemical analyses (pH, volatile fatty acids, lactic acid, ammonia) were assessed in pre-fermentation (d 0), and post-fermentation (d 60). Nutritional quality was evaluated according to AOAC standard methods. Statistical analyses employed mixed models for nutritional and fermentation data, with drying treatments (C, PD, SD) as fixed effects. All mature silages were greater in crude protein (15.2 to 15.7%), crude fat (6.0 to 6.3%), sodium (0.48 to 0.52 %), sugars (WSC; 0.95 to 1.53 %), and less in neutral detergent fiber (6.2 to 7.6%) as compared with traditional silages used as livestock feed. Fermentation parameters showed that lactic acid content was greater than acetic acid, and pH decreased from a maximum of 5.26 at d 0 to a minimum of 3.85 at d 60. Mycophenolic acid was the only mycotoxin above the limit of detection in d 0 silage, with all mycotoxins below reference concentrations at d 60. Plate counts of molds and yeasts declined (P < 0.001) by 5 to 7 log colony-forming units (CFU) over 60 d of fermentation and were not detected in mature silage. Silage showed aerobic stability after 20 d of aerobic exposure (pH 3.86 ± 0.027). In conclusion, ensiling FW could be a viable way of converting low-value waste products into good-quality feed. However, approaches other than SD and PD are required for increasing silage DM as insufficient bread products may be available for this purpose in all batches of FW. Further study of palatability along with digestibility testing will be needed for a scaling-up process.
PSXI-3 Mineral changes of stacked, composted and vermicomposted manure from finishing pigs fed diets low in energy, calcium, phosphorus and trace minerals and added with exogenous enzymes
Authors: de Angeles Maria Lourdes , Gomez-Rosales Sergio , Perez-Alvarado Alejandra
Published: September 2024

The objective of the study was to evaluate the changes in the concentration of macro- and micro-minerals of manure left in a manure stack or subjected to composting or vermicomposting excreted by finishing pigs fed diets reduced in metabolizable energy (ME), Ca, P and trace minerals and added with the exogenous enzymes phytase, xylanase and pectinase. Pigs were distributed into 3 treatments: 1) A Sorghum/soybean meal diet formulated to meet all the nutrient requirements, with a mineral premix based on sulfates; 2) Same as 1) but reduced in ME, Ca and P, and with reduction of 33.3% of the mineral premix, added with phytase, xylanase and pectinase; or 3) Same as 2), but with reduction of 66.6% of the mineral premix. The manure was collected every day from the pens and taken to a greenhouse with natural ventilation. One part of the manure was left in stacks, and the other part was subjected to precomposting for 28 d. After that, the precomposted manure was split in two; one part was left on the same trough and the second one was separated and inoculated with Red Californian worms. The composted and vermicomposted manure underwent a humification process for 90 d. At the beginning (fresh and precomposted manure) and end (stacked, composted and vermicomposted manure) of the study, samples were taken for analysis. The dry mater, ashes, total nitrogen, Ca, P, K, Na, Mg, Fe, Zn, Mn and Cu were determined. Results are expressed on a dry matter (DM) basis. There were three replications of manure piles, compost and vermicompost per treatment. Data were analyzed for a completely randomized design using the GLM procedures of SAS. In fresh manure, reduced Zn (1 = 334, 2 = 342 and 3 = 250 mg; P < 0.0456) and Mn (1 = 138, 2 = 135 and 3 = 119 mg; P < 0.050) were found in the manure originated from pigs fed diet 3) with a reduction of 66.6% of the mineral premix. At the end of the study, reduced P (1 = 1.21, 2 = 1.07 and 3 = 1.08%; P < 0.012), Zn (1 = 1103, 2 = 997 and 3 = 865 mg; P < 0.047), Mn (1 = 193, 2 = 167 and 3 = 146 mg; P < 0.019) and Cu (1 = 71, 2 = 53 and 3 = 45 mg; P < 0.003) were observed in the stacked manure originated from pigs fed diet 3). Reduced P (1 = 1.13, 2 = 1.07 and 3 = 0.95%; P < 0.014), Mn (1 = 235, 2 = 201 and 3 = 196 mg; P < 0.017) and Cu (1 = 47, 2 = 40 and 3 = 35 mg; P < 0.006) were found in the composted manure from pigs fed diet 3). In conclusion, in fresh manure from pigs fed reduced ME, Ca, P and mineral premix only Zn and Mn were reduced, whereas reduced P, Zn, Mn and Cu in stacked manure and reduced P, Mn and Cu in composted manure were found.
PSIV-30 Moderate maternal nutrient restriction in beef heifers reduces fetal crown-rump length at day 35 of gestation
Authors: Faust Mikayla M , Hauxwell Kathlyn M , Ward Alison K , Dahlen Carl R , Swanson Rebecca , Syring Jessie G , Entzie Yssi L , King Layla , Hurlbert Jennifer L , Caton Joel S
Published: September 2024

One-carbon metabolite (OCM) supplementation in beef cattle has been shown to be a novel strategy that alters programming outcomes in tissues of the developing fetus. However, information regarding growth changes to the fetus during early gestation is limited. The objective of this study was to evaluate the effects of OCM supplementation in control-fed or nutrient-restricted pregnant heifers on fetal crown-rump length (CRL) during early gestation. We hypothesized that decreased nutrient availability in the maternal system would impact the growth of the fetus in utero and providing OCM supplementation would restore growth levels in a nutrient restricted environment. Angus crossbred heifers [n = 216; initial body weight (BW) = 365 ± 5.45 kg] across three replicates underwent estrus synchronization and bred via artificial insemination (AI) using female-sexed semen from a single sire. At breeding (d 0), heifers were assigned to treatments in a 2 × 2 factorial design, which included two levels of daily gain; control (CON; +0.45 kg/d gain) or restricted (RES; −0.23 kg/d gain) and supplementation of OCM [+OCM; rumen protected choline (44.4 g/d) and methionine (7.4 g/d) in a ground corn carrier and weekly injections of 320 mg folate and 20 mg vitamin B12] or no supplementation (-OCM; corn carrier and saline injections). Heifers were weighed weekly, and diets were adjusted on a dry matter basis of the total mixed ration to maintain targeted gain. Treatments were maintained through d 63 of gestation in pregnant heifers. Pregnancy diagnosis and fetal CRL was determined via transrectal ultrasonography on d 35. A total of 103 heifers were confirmed pregnant (replicate 1, n = 37; replicate 2, n = 32; replicate 3, n = 34). Data were analyzed using the MIXED procedures of SAS as a 2 × 2 factorial including the effects of two levels of gain, two levels of OCM treatment, replicate, and their two-way and three-way interactions. There were no three-way interactions between gain × treatment × replicate. However, there was a gain × treatment interaction (P ≤ 0.05), in which fetuses from RES heifers with and without OCM supplementation had reduced CRL compared with fetuses from CON heifers that did not receive OCM (14.15 ± 0.21 mm, 13.88 ± 0.21 mm, 14.84 ± 0.21 mm, respectively). Fetal CRL from OCM supplemented CON heifers was similar (P = 0.06) to all other treatments (14.27 ± 0.21 mm). In conclusion, fetuses from RES heifers exhibited a decreased CRL, and OCM supplementation did not mitigate these effects.
PSV-27 Optimizing corn silage utilization in beef feedlot diets: Evaluating the impact of exogenous glucoamylase addition on performance and digestibility
Authors: Schoonmaker Jon P , Nolasco Lester , Vincent Tyler J , Torres Rodrigo
Published: September 2024

The addition of an exogenous glucoamylase enzyme preparation to feedlot diets that contain a high percentage of corn silage may improve digestibility and yield positive outcomes in growth and efficiency. However, it is unclear what concentration of corn silage in the diet would most benefit from exogenous glucoamylase. Crossbred steers [n = 180; body weight (BW) = 459 ± 11.8 kg] were divided into 30 pens (5 pens per treatment; 6 steers per pen) and assigned to one of six treatments arranged as a 3 x 2 factorial investigating 3 forage concentrations (15, 42, and 69% corn silage) and 2 exogenous glucoamylase additions (0 or 183 enzyme units/kg of dry matter per d). Steers were fed 42% corn silage, 30% corn, 23% dried distillers grains with solubles, and 5% supplement at feedlot entry and for 2 wk prior to initiation of the study. Steers on the 15% and 69% corn silage diets were transitioned to treatment diets by wk 3 of the study (d 15), with the first transition occurring on d 0. Diet transitions occurred once weekly. The animals were on feed for 105 ± 10.4 d and had ad libitum access to feed and water. Average daily gain (ADG), dry matter intake (DMI), and gain:feed were assessed both overall and for two distinct periods: d 0 to 50, and d 51 until slaughter. Data analysis was performed using the GLIMMIX procedure of SAS. From d 0 to 50, ADG, DMI, and gain:feed did not differ due to forage concentration or enzyme inclusion and there was no interaction (P ≥ 0.39). For d 51 to slaughter, enzyme inclusion interacted with forage concentration such that the enzyme improved ADG (P = 0.0003) and gain:feed (P = 0.01) for steers fed the 42% corn silage diet but did not effect ADG and gain:feed for steers fed the 15 or 69% corn silage diets. For d 51 to slaughter DMI was not affected by forage concentration, enzyme inclusion, or their interaction (P ≥ 0.21). When calculated for the entire study (d 0 to slaughter), increasing forage concentration decreased ADG and gain:feed (P ≤ 0.0006), but did not effect DMI (P = 0.22). Overall, enzyme addition did not impact ADG, DMI, or gain:feed and did not interact with forage concentration (P ≥ 0.50). Carcass characteristics were not affected by forage concentration, enzyme addition, or their interaction (P ≥ 0.19). Overall results suggest that an exogenous glucoamylase enzyme improves growth and efficiency of heavier feedlot cattle fed moderate amounts of forage later in the feeding period.
PSX-23 Use of time series data in the prediction of beef cattle dry matter intake using machine learning
Authors: Walker Matthew , Blake Nathan , ArunKumar K E , Mata-Padrino Domingo , Holaskova Ida , Wilson Matthew E
Published: September 2024

Improvements in technology that facilitate the estimation of individual animal dry matter intake (DMI) in any setting, whether in confinement or on pasture, will improve beef cattleproduction and management. Big Data approaches could further enhance DMI estimation. In this work, we improved upon our predictive models by developing variable time series features and forgoing the use of full-test Average Daily Gain, a variable that provides unwanted intake information during model training, in DMI prediction. We implemented the improved time series analysis techniques of first differences, moving averages, and seasonal decomposition to create new predictive variables from daily-level data. These new variables were used in k-fold cross-validation to improve the variable selection process and prediction accuracy of the Random Forests Regression (RFR) and Repeated Measures Random Forests (RMRF) models. Reduced models for the RFR and RMRF algorithms were identified, assessed, and compared with estimated DMI calculated using the current NASEM equation for estimation of beef cattle DMI. Data on feed intake, animal weights, and climate conditions were collected from 25 November2019 to 20 February 2020 for bulls and from 19 March 2020 to 7 May 2020 for steers. Feed intakes were recorded using Vytelle Feed Intake Nodes. Animal body weights (BW) and water intakes were measured daily using Vytelle In-Pen-Weighing Positions and metered waterers. Climate data included information on temperature, humidity, precipitation, and wind speed and were recorded at 30-min intervals. We found that seasonally-adjusted and moving averaged features generally outperformed first difference features. The baseline models presented here performed similarly to our previous models, despite using ‘Average Daily Gain to Date’ rather than the ‘Full Test Average Daily Gain’. The range of R2 was 0.44 to 0.69 and the range of RMSE was 0.95 to1.67 kg. Additionally, use of Average Daily Gain to Date in place of full-test Average Daily Gain improves the field deployability of our models. Lastly, while the demonstrated models can both over- or under- predict daily DMI, both RFR and RMRF showed more accurate predictive ability than the current NASEM equation. This study further demonstrates the potential of RFR and RMRF models DMI prediction of beef cattle. Future research will focus on including a wider range of cattle breeds, climatic conditions, and geographic locations, as well as assessment of suitability of RFR and RMRF for DMI prediction of cattle on pasture.
PSXI-7 Effects of selected feed additives on feedlot cattle performance when fed diets containing rehydrated corn grain silage
Authors: Francischinelli André F , Gouvêa Daniel L C G , Ribeiro Vitória A M , Carvalho Victor , Perdigão Alexandre , Pereira Murilo C S , Arrigoni Mário B B , Martins Cyntia L L
Published: September 2024

The use of additives makes it possible to improve body weight (BW) gain and muscle growth, the efficiency of nutrient use, in addition to reducing the incidence of metabolic disorders. The objective of the study was to evaluate the performance, feed intake and carcass production of feedlot Nelore cattle, fed with a high concentrate diet, using different feed additives. Nelore bulls [n = 48; initial BW (BWi = 378.1 kg ± 8.92 kg; 20 mo of age), were used. Bulls were allocated in a collective pen, randomly distributed in two treatments: 1) Sodium Monensin (MON), 26 mg/kg DM; and2) CRINA + RUMISTAR + Hy-D (CRD), blend of essential oils, 90 mg/kg DM + exogenous α-amylase, 560 mg/kg DM + 25 hydroxyvitamin D3, 1 mgּ animal-1ּ d-1

. The experiment lasted 101 d, the animals were weighed fasting (± 16 h) at the beginning and end of the experiment, at the end of the experiment the animals were subjected to carcass ultrasound, dry matter intake (DMI) was measured daily individually using electronic troughs with selector doors (Intergado, PONTA, Betim, MG-Brazil). The initial carcass weight (195.6 kg, P = 1.0) was estimated using the equation HCWi = 0.6587*BWi-53.44 (R² = 0.993), obtained through the reference slaughter of 9 animals, and the final carcass weight measured in the refrigerator. The “step-up” adaptation protocol lasted 15 d, followed by the finishing diet until the end of the experimental period, consisting of ground corn, rehydrated corn grain silage, cottonseed cake, whole cottonseed, sugarcane bagasse, urea and vitamin-mineral supplement. Data were analyzed by SAS PROC ANOVA, using BWi as a covariate when significant. Animals fed CRD had a greater final BW (534.0 vs 515.6 kg, P = 0.003) and increased average daily gain (ADG) by 0.180 kg/d (1.54 vs 1.36 kg/d, P = 0.003). DMI was greater (10.2 vs 9.3 kg/d, P < 0.001) as well as DMI:BW (2.24 vs 2.09 %BW/d, P < 0.001). The feed efficiency did not differ between treatments (P = 0.21). Animals fed CRD presented heavier HCW (305 vs 291 kg, P = 0.004) and ADG carcass (1.08 vs 0.95 kg/d, P = 0.004). The carcass conversion, calculated as kg DM/15 kg carcass produced (143.5 vs 152.6, P = 0.11), carcass yield (P = 0.15), 12th ribeye area (P = 0.52) and 12th rib fat (P = 0.12), were similar among the treatments. Feeding CRD tended to improve marbling (1.67 vs 1.45%, P = 0.08). These results underscore the potential of CRD as an effective alternative to traditional additives in enhancing the performance and carcass quality of feedlot cattle.
PSXI-21 Effect of the inclusion of increasing levels of three tree species on methane production and nutrient digestibility in vitro
Authors: Vazquez-Carrillo Maria Fernanda , López-Varela Jimena Yaxen , Romero-Pérez Atmir , Avilés-Nieto Jonathan Noé , Talamantes-Montes José Moises , Marquez-Mota Claudia Cecilia , Corona-Gochi Luis
Published: September 2024

Beef production is a major contributor to the world’s food system. However, it also represents a significant source of enteric methane (CH4). Currently, the incorporation of plants with increased concentrations of secondary metabolites has been highlighted as a strategy to mitigate enteric CH4. The objective of the present study was to evaluate the effect of increasing levels of three tropical trees in combination with a tropical pasture on total gas production, dry matter (DM) digestibility, neutral and acid detergent fiber (NDF and ADF, respectively) and volatile fatty acid concentration under in vitro conditions. Treatments were arranged in a completely randomized block design with 3 × 4 factorial arrangement, including three tree species [Gliricidia sepium (GS); Guazuma ulmifolia (GU) and Leucaena leucocephala (LL; Table 1)] × four increasing levels of inclusion (0, 15, 30 and 45%). Each experimental treatment was incubated in triplicate in three independent runs (blocks). All experimental units were incubated with 0.5 g of substrate (mixture of arborea with tropical grass) and gas production was measured at different times 0, 2, 4, 6, 8, 8, 10, 12, 14, 16, 20, 24, 30, 36, 48, 60 and 72 h of incubation. Ruminal fermentation was measured by the in vitro gas production technique, using a ruminal inoculum from three bovine donors. The data were analyzed with the MIXED procedure of SAS, and the comparison of means was analyzed with Tukey. The treatments that presented greater NDF digestibility were GS45 (53.79%) and GS15 (51.19%) while for ADF they were GS15 (35.15%) and GU15 (35.28%) and for DM it was GS30 with 71.32% (P < 0.05; Table 2). As for the volume of CH4 produced LL45 presented the least value (10.01%), following the same trend its NDF digestibility with 38.5% (P < 0.0001). While GU45 produced the lowest volume ml CH4 /g DM, NDF and ADF producing 25.83, 52.87 and 109.74 ml (P < 0.0001). Likewise, the tree species that had a reduced response in CH4 production were GU and LL compared with GS (P < 0.0001) also presenting a greater concentration of total and condensed tannins. The incorporation of forage plants with increased concentration of secondary metabolites and the reduced availability of digestible substrate in the present study reduced CH4 production in vitro. This study was partially funded by PAPIIT-DGAPA-UNAM (grant IN212523).
PSXI-29 Effects of Vitamin B6 supplementation on rumen fermentation and branched chain fatty acids content in vitro
Authors: Guo Xin , Zhan Tengfei , Ma Lu , Bu Dengpan
Published: September 2024

Vitamin B6 promotes branched-chain amino acid aminotransferases in branched chain fatty acids (BCFA) synthesis pathways. This study aimed to investigate the effects of Vitamin B6 supplementation in total mixed ration on rumen fermentation characteristics and the rumen BCFA content in vitro. Treatments were set as dose response with 0, 3, 6, 12 and 24 mg/kg dry matter (DM) Vitamin B6. Each incubated with 75 mL of buffered rumen fluid and 0.5 g of fermentation substrate for 24 h at 39°C. Five replicate parallel fermentation flasks were prepared by each level of supplemented Vitamin B6, and incubation was repeated twice. Filtered fluid with Nylon bags were collected from each fermentation flask. The contents of volatile fatty acids (VFA) and BCFA were determined using an Agilent 6890N GC equipped with a flame ionization detector. All data were analyzed using the linear mixed model of nlme Package in R (version 4.3.1). Compared with the control group, the concentration of total branched chain volatile fatty acids, propionic acid, butyric acid, valeric acid, isobutyric acid and isovaleric acid at 3 mg/kg DM Vitamin B6 significantly decreased, while the ratio of acetic acid to propionic acid was significantly increased (P < 0.01). As the dose of Vitamin B6 increased, the concentrations of iso-C14:0, iso-C15:0, anteiso-C17:0 changed quadratically with greatest at 3 mg/kg DM Vitamin B6 (P < 0.05). Compared with the control group, the contents of iso-C13:0, iso-C14:0, iso-C15:0, anteiso-C15:0, anteiso-C17:0, iso, anteiso and BCFA at 3 mg/kg DM Vitamin B6 significantly increased (P < 0.01). The contents of total iso, anteiso and BCFA increased by 18.80 %, 35.37 % and 22.58 %, respectively, compared with the control. In summary, the results of this study indicated that 3 mg/kg DM Vitamin B6 had beneficial effects on increasing BCFA content than other groups.
PSXI-11 In vitro rumen fermentation characteristics of rumen fluid obtained from grain-fed and grass-fed farmed American Bison
Authors: Okoren Claire E , Engle Terry E , Edwards-Callaway Lily N
Published: September 2024

The objective of this pilot study was to examine the impact of diet type on in vitro rumen fermentation characteristics using rumen fluid collected from grain-fed and grass-fed American Bison (Bison bison). Rumen fluid was collected from 6 farmed American Bison at a commercial slaughter facility. At the time of slaughter, 3 grain-fed heifers (< 3 yr) were randomly selected for rumen fluid collection. On a separate day, 3 grass-fed cows (>3 yr) were randomly selected for rumen fluid collection. Rumen fluid was collected from each animal by obtaining rumen contents and filtering the rumen fluid from the digesta. For a given collection day, rumen fluid from the 3 animals was combined with McDougall’s buffering solution to generate rumen fluid buffer solution (RFB). The RFB was added to each pre-weighed digestion vessels (DV) containing no substrate (blanks) or 0.5 g of ground substrate (grain-based diet or forage-based diet). After filling, the DV were capped with one-way valves and incubated for 0, 12, 24, 48, and 72 h. At the end of each incubation period, DV were centrifuged, and supernatant was removed and analyzed for VFA concentrations. The remaining pellet was dried at 60°C for 24 h to determine dry matter digestibility (DMD). Descriptive statistics were used to describe DMD characteristics for rumen fluid collected from bison from each production system. Linear, quadratic, and cubic responses were analyzed for DMD. Linear, quadratic, and cubic contrasts were used to examine DMD over time. In vitro DMD increased quadratically (P < 0.05) for grain-fed bison and linearly (P < 0.05) for grass-fed bison over time. Final 72 h DMD was 84.5% ± 0.05 and 70.0% ± 0.11 for grain-fed and grass-fed bison, respectively. Final molar proportions of acetate, propionate, isobutyrate, and butyrate were 55.3% ± 0.01, 25.8% ± 0.002, 1.9% ± 0.01, and 17.0% ± 0.001 for grain-fed bison and 31.0% ± 0.02, 41.2 ± 0.02, 3.9% ± 0.01, and 23.2% ± 0.01 for grass-fed bison. Molar proportions of all VFA exhibited a cubic response (P < 0.05) over time for rumen fluid collected from both grain-fed and grass-fed bison. These data provide a preliminary insight into in vitro rumen fermentation characteristics of bison from different production systems.
PSXI-17 Comparison of enteric methane production between the respiration chamber and the CO2 method in Holstein heifers
Authors: Lee Jaesung , Bharanidharan Rajaraman , Oh Junseok , Im Seyun , Kim Sang Yeob , Ranaweera Namal , Kim Kyoung Hoon , Baik Myunggi
Published: September 2024

The objective of this study was to validate the carbon dioxide (CO2) method (CO2T) in comparison with the respiration chamber (RC) method for the measurement of enteric methane (CH4) emission. The study was conducted over 108 d with Holstein heifers [n = 10; initial body weight (BW) = 178 kg; and age, 7.7 mo). The study consisted of 3 consecutive measurement periods and each period consisted of 21 d of feed adaptation followed by 15 d of CH4 measurement using the CO2T (3 d) and the RC method (12 d). The 55% timothy hay and 45% concentrate were fed twice daily at 1.2% to 1.5% of BW on an as-fed basis. The CO2T was used for 3 d during the morning and afternoon feeding. For the CO2T, CH4 and CO2 concentrations of exhaled breath from each animal were continuously analyzed by gas analyzers and recorded every 10 sec for 10 min per animal. The CH4:CO2 ratio of the data were calculated and multiplied by daily CO2 production of each animal to determine daily CH4 production. Right after the CO2T measurement, CH4 emission was measured using the RC method by the difference between the inlet and outlet CH4 concentration of the RC. Statistical analyses were performed using the software R version 4.0.4. Differences in dry matter intake (DMI), CH4 production, and CH4 yield between the two methods were tested using the Wilcoxon signed-rank test. DMI was not different between the RC method and the CO2T measurements. The CH4 production (L/d, L/kg BW0.75) and yield (L/kg DMI) determined by two methods were similar (127 vs 120 L/d, 2.05 vs 2.16 L/kg BW0.75, and 23.5 vs 21.6 L/kg DMI for RC vs CO2T, respectively). There was a positive relationship between DMI (kg/d) and CH4 production (L/d) for both of the RC method (R2 = 0.46, P < 0.05) and the CO2T (R2 = 0.72, P < 0.01). Linear regression analysis of CH4 production (L/d) between the RC method and the CO2T showed a moderate positive relationship (R2 = 0.52, P < 0.05). Pearson correlation analyses showed a strong relationship between the RC method and the CO2T for CH4 production (L/d; R2 = 0.72, P < 0.05). In conclusion, the CH4 production of Holstein heifers estimated by the CO2T did not differ from that measured by the RC method, and method agreement indices showed moderate positive correlations. The CO2 method could be used as one of the alternative CH4 measurement techniques comparable to the respiration chamber method.
PSXI-9 Impact of copper dose and soybean oil on in vitro ruminal fermentation products
Authors: Rodezno-Gomez Arturo , Thomas Tyler A , Oliveira Joyce , Loh Huey Yi , Thorndyke Meghan P , Miller Alexandra C , Alves Julia Baroni , Engle Terry E
Published: September 2024

The objective of this experiment was to determine the impact of copper (Cu) dose on microbial fermentation products and biohydrogenation of soybean oil (SBO) using an in vitro rumen fermentation technique. Two heifers [body weight (BW) = 408 and 422 kg] fitted with ruminal canulae were fed a high concentrate diet for 14 d. On d 15, rumen fluid samples were obtained 2 h post-feeding from both animals and combined into one pre-warmed (39°C) container. Anaerobic conditions were maintained by bubbling carbon dioxide (CO2) into McDougall’s buffer, while two volumes of rumen fluid were added to each volume of McDougall’s buffer. The suspension was mixed under CO2 as 30-mL portions were added to pre-weighed vaccine bottles containing 0.5 g of substrate (ground basal finishing diet with no supplemental Cu or SBO). The basal diet contained 4.2 mg Cu/kg dry matter (DM). Treatments were assigned to vaccine bottles in a 2 x 3 factorial arrangement with factors being SBO (0 or 3.5%) and Cu (0, 10, or 20 mg/kg DM) relative to substrate DM. Each treatment was replicated 6 times. Following treatment administration, all vaccine bottles were caped and sealed to maintain anaerobic condition and incubated at 39°C. Vaccine bottles were swirled by hand at the time of gas sample collection at 0, 2, 4, 6, 8, 10, 12, 18, 24, 36, and 48 h post-inoculation. Samples were immediately analyzed for methane (CH4) and CO2. Following every gas sampling timepoint, the vaccine bottles were degassed. At the end of the 48-h incubation, all vaccine bottles were centrifuged, and 2 mL of supernatant were removed and acidified with 25% metaphosphoric acid for volatile fatty acid (VFA) determination, and another 5 mL of supernatant were removed and analyzed for long chain fatty acids. The remaining supernatant was decanted, and the vaccine bottles were dried at 60°C for 72 h to determine DM disappearance (DMD). Data were analyzed as a randomized block design for a 2 x 3 factorial arrangement of treatment using PROC MIXED of SAS. Forty-eight hour DMD, CO2 production, molar percent of acetate, propionate, and butyrate, total mM of VFA, and pH were unaffected by treatment. Methane production per unit of DMD decreased (P < 0.05) in fermentation bottles containing SBO but increased (P < 0.04) in fermentation bottles containing Cu. Soybean oil addition increased C16:0, C18:0, C18:1, C18:2, and C18:3 fatty acids at 48 h. Copper addition tended to decrease C18:0 (P < 0.07) and tended to increased C18:1 (P < 0.06) and C18:3 (P < 0.09) fatty acids. These data suggest that Cu may decrease biohydrogenation in vaccine bottles not containing SBO but increases ruminal biohydrogenation in vaccine bottles containing SBO.
PSXI-27 Supplementing Bovacillus to feedlot cattle finished under heat stress conditions
Authors: Mackey Shea , Cooke Reinaldo F , Pickett Autumn , Cappellozza Bruno I
Published: September 2024

This experiment compared performance, physiological, and carcass responses of finishing cattle receiving a Bacillus-based probiotic under heat stress conditions. Angus-influenced steers (n = 113) were purchased from an auction yard and assigned to the experiment [arrival body weight (BW) = 345 ± 2.7 kg]. On d 0, steers were ranked by initial BW and allocated to 1 of 20 drylot pens (5 or 6 steers/pen). Pens were randomly assigned to receive a finishing diet containing BOV (3 gּ animal-1ּ d-1 Bovacillus) or no additive (CON) until slaughter. Diets contained monensin but not tylosin. Steer BW was recorded on d 0, 28, 56, 84, 112, and at the time of shipping, which was considered final BW. Initial and final BW were used in average daily gain (ADG) calculation. Blood samples were collected immediately after BW assessment on d 0, 28, 56, 112 of the experiment as well as 8 d prior to slaughter. Plasma was analyzed for concentrations of alanine aminotransferase, aspartate transferase, alkaline phosphatase, gamma-glutamyl transferase, bilirubin, and blood urea nitrogen. Real-time temperature and humidity were recorded every hour for the duration of the trial for temperature-humidity index (THI) assessment. Steers were shipped to a packing facility (Tyson; Amarillo, TX) in 3 groups according to BW, which contained an equal number of pens from both treatments. Upon slaughter, hot carcass weight, backfat thickness, Longissimus muscle area, USDA marbling score, USDA yield and quality, and liver abscess score were recorded. The THI during the first and second thirds of the experimental period (79.8 and 78.1, respectively; SEM = 0.22) were substantially above the heat stress threshold (THI = 72). No treatment differences were recorded for BW parameters, ADG, or gain to feed ratio (P ≥ 0.21), despite a 10 kg increase in final BW and a 4 kg increase in hot carcass weight in BOV steers. Dry matter intake did not differ among treatments (P = 0.48). No treatment differences were recorded for carcass quality response, although incidence of liver abscess was reduced in BOV compared with CON groups (7.3 vs 19.0%; P = 0.04). A treatment × day interaction was detected (P = 0.02) for plasma concentration of GGT, which tended (P = 0.08) to be greater for CON vs. BOV steers on d 56. No other treatment differences were detected for plasma metabolites (P ≥ 0.69). Collectively, BOV supplementation mitigated the incidence of liver abscesses in finishing cattle, whereas improvements to steer performance were only numerical.
PSXII-21 How does the inclusion of dried distillers grains plus soluble affect short-chain fatty acid and methane production in feedlot diets?
Authors: de Coelho Larissa M , Furtado Althieres J , de Santos Torres Rodrigo Nazaré S , Consilio Maristela , Oliveira Mário O , Lima Lidia M , Junior Flavio Perna , Tedeschi Luis O , Oliveira Patricia P A , Almeida Amelia K , Santos Flávio Augusto Portela
Published: September 2024

The inclusion of the coproduct dry distillers grains plus soluble (DDGS) in the diet of finishing cattle can lead to changes in the nutritional profile of the diets, causing an increase in protein content and a reduction in starch. It is necessary to understand how changes in rumen substrates affect rumen metabolic activity, acids, and enteric methane (CH4) production. Five treatments were used, considering levels of DDGS inclusion in the dry matter (DM) of 1) 0 g/kg of DDGS, 2) 150 g/kg of DDGS, 3) 300 g/kg of DDGS, 4) 450 g/kg DDGS, or 5) 600 g/kg DDGS in finishing diets. The metabolism experiment was conducted with rumen-cannulated Nellore bulls (n = 20) with initial body weight (BW) of 401.8 ± 27.0 kg. The production of short-chain fatty acids (SCFA) and CH4 were determined using the ex-situ ruminal fermentation technique. Rumen content was manually collected from 0, 4, 8 and 12 h post-feeding. The liquid and solid fractions of rumen content were used in four 50 mL penicillin-type flasks per animal. Of the four flasks prepared, two are called “blank” and inactivated in boiling water to stop fermentation, and the other two (microrumen) are incubated in a thermostatic bath, simulating the conditions existing in the rumen of animals (presence of microorganisms, anaerobes, temperature of 39ºC, natural animal saliva, physiological pH) for 30 min. After 30 min, incubated flasks were also inactivated in boiling water to stop fermentation. Subsequently, measurements of the final products of rumen fermentation (SCFA and CH4) were carried out in each bottle. Total rumen emptying was performed to determine the rumen pool of DM. The data will be analyzed in the SAS software, the mean of the treatments will be compared using test of mean and orthogonal contrasts. The declared significance is P ≤ 0.05. The inclusion or levels of DDGS did not affect CH4 production of gּ kg DM-1ּ d-1 and gּ kg DM-1ּ d-1 (P > 0.05). There was an effect of the treatments on the production of propionate (gּ kg DM-1ּ d-1; P = 0.0448), with a decreasing linear effect (P = 0.0087) with the increase in the inclusion of DDGS in diet (0; 150; 300; 450; 600 g/kg of DDGS; means 137.20; 160.32; 117.60; 87.09; 91.52 gּ kg DM-1ּ d-1 propionate, respectively). There was no effect of DDGS levels on the production of Acetate, Butyrate, or total SCFAs (gּ kg DM-1ּ d-1). In summary, DDGS inclusion affects rumen metabolic activity, decreasing propionate production, but does not affect the production of other SCFAs nor CH4 production.
PSXII-22 Ruminal in situ dry matter and starch degradability in grain sorghum silage, as affected by processing and storage time
Authors: Abdelhadi Leandro O , Maderal Araceli B , Fernandez-Marenchino Ignacio , de Vargas Juan J , Fernandez-Lehman Andres , Tarnonsky Federico , Mattioli Guillermo , DiLorenzo Nicolas
Published: September 2024

Our previous studies showed that processing sorghum silage at harvest and storing for approximately 150 d, improved average daily gain (ADG), feed efficiency (FE) and apparent total tract digestibility (ATTD) of starch when included as the basal ingredient in diets fed to growing Angus heifers. However, differences in animal performance and nutrient digestibility disappeared when the same sorghum silage was fed again after 1 yr of storage. An experiment was performed to evaluate the effects of kernel processing and storage time on ruminal in situ degradability of sorghum silage (SS). A grain sorghum (ADV2450IG, Advanta seeds, Irving, TX) was harvested (Claas Jaguar 930, Harsewinkel, Germany) at the late-dough stage of grain maturity. Treatments were applied at harvest and consisted of sorghum berry processing (PRO) with a specific SS kernel processor (196 mm rolls of 125 teeth each, 40% speed differential, 1.1 mm roll gap), or not processed at all (NPR). Silage was chopped at 15 mm theoretical length of cut and ensiled in polyethylene ag bags (60 m long and 2.74 m diameter), for 455 d. Samples were taken from each treatment on d 0, 66, 112, 157, 202, 246, 291, 336, 381, 426, and 455 and were kept frozen until analyzed. Samples were dried but not ground, to avoid affecting treatments. Ruminal in situ degradability of dry matter (DM) and starch was determined by incubating nylon bags for 24 h in duplicate, in the rumen of four ruminally cannulated steers consuming a corn silage-based diet. Data were analyzed as a randomized block design with repeated measures. The fixed effect of treatment, day and their interaction were included in the model and the repeated subject was considered the animal within treatment. A storage day × treatment interaction was detected for in situ DM degradability (P < 0.001). The PRO treatment increased (P < 0.05) in situ DM degradability at 66 and 202 d of storage and tended to increase it (P = 0.07) at 157 and 291 d of storage. An effect of storage day (P < 0.05) was observed for in situ starch degradability and because there was no interaction with treatment (P = 0.43), treatments means were compared across storage days. No differences were detected in ruminal in situ digestibility of DM or starch when silage was stored for 202 d, when compared with d 0 (P = 0.43), while starch degradability increased when silage was stored for 202 and 291 d (P < 0.03). At 381 d of storage, no differences were detected for starch degradability when compared with d 0. In conclusion, berry processing of sorghum when harvested for silage, increased ruminal in situ DM degradability. However, those differences disappear after more than 200 d of storage, in agreement with animal performance data previously reported by our group.
PSXIII-22 Intake, digestibility, and ruminal parameters of Nellore cattle fed with amylolytic and fibrolytic enzymes in feedlot
Authors: Ferreira Igor Machado Machado , Rodrigues Aline Naime Naime , José Inácio de Abreu Mateus José Inácio , Teixeira Rodrigues de Almeida Saulo T , David Gabriel Santos Souza , Domingos Bianca Rodrigues , Viquez-Umana Fiorella L , Rodrigues Arlan Araújo , Cuquetto Mantovani Hilário C , Silva Luiz Fernando Costa e , Koontz Anne , Siqueira Gustavo Rezende Rezende , de Resende Flávio Dutra de Dutra
Published: September 2024

This study was carried out to evaluate the use of dietary exogenous enzyme (ENZ) products with amylolytic and fibrolytic activity on nutrient intake, digestibility, and ruminal volatile fatty acids production (VFA) of Nellore cattle in feedlot. Rumen-cannulated Nellore steers [n = 10; body weight (BW) = 543 kg ± 28.6 BW] were distributed in a replicated Latin-square design (5 × 5) in individual pens. The treatments consisted of a negative control (CON; without ENZ); Amylase (AML; Amaize, Alltech, 0.5 g/kg of DM); Xylanase (FBL, Fibrozyme, Alltech, 0.9 g/kg of DM); Half dose (HD; AML 0.25 g/kg of diet DM and FBL 0.45 g/kg of diet DM); and Full dose (FD; AML 0.5 g/kg of diet DM and FBL 0.90 g/kg of diet DM; Table 1). The experimental period lasted 19 d (14 d of adaptation and 5 d of collection). Between d 15 and 18, total fecal collection was performed and on d 19 rumen fluid was collected at 0, 4, 8, 12, and 16 h post-feeding for ammonia, VFA, and pH determination. The data were analyzed as orthogonal contrasts using SAS: (C1) CON vs. ENZ, (C2) AML vs. FBL, (C3) HD vs. FD, and (C4) AML + FBL vs. HD + FD. There were no C1 differences for nutrient digestibility, total VFA, or ruminal pH (P > 0.10). However, a tendency effect in neutral detergent fiber (NDF) intake (P = 0.065) was observed, where animals fed ENZ had reduced values compared with animals kept in CON group. In the same way, ENZ reduced ther extract (EE) intake (P = 0.023), ruminal ammonia (P < 0.001), and isovalerate proportion (P = 0.080) as well as increased proportion of acetate (P < 0.001), valerate (P < 0.001) and acetate:propionate ratio (P = 0.030). No differences were observed in nutrient intake between AML and FBL (P > 0.10), but AML had greater organic matter (OM) digestibility (P = 0.097) and ruminal valerate (P = 0.039) and decreased butyrate proportion (P = 0.068). Animals that received FD had greater values of dry matter (DM; P = 0.009) and OM (P < 0.001) digestibility than HD. The enzyme combination resulted in greater DM (P = 0.026), OM (P = 0.062), crude protein (P = 0.018), EE (P = 0.063) and NDF (P = 0.040) intake and reduced OM digestibility (P = 0.008) compared with AML and FBL alone. The addition of exogenous enzymes in feedlot diets affected nutrient utilization and ruminal fermentation of Nellore cattle fed a feedlot finishing diet.
PSIX-27 Ultrasound scanning of carcass traits in Katahdin lambs for predictive breeding value and marketing premium
Authors: Wuliji Tumen , Lourenco Raquel V , Tu Niya , Davis Dennis
Published: September 2024

Ultrasound scanning (USS) technique has been routinely used in performance testing of meat animals, such as swine and beef cattle. This study is to evaluate USS application in organic lamb production, selection, and the accuracy of carcass traits and market value prediction. Ewes (n = 60) were bred, pregnancy diagnosed at 40 d post-mating, and their suckling lambs were assigned to two groups, a non-creep feeding (control) and creep feeding (treatment) group. Each group was balanced with sexes and litter size when allocated into groups at 30-d of age. All lambs had unrestricted suckled their dams during pasture grazing or grazing with creep feeding supplementation until weaning. There were 28 control and 32 treatment group lambs presented at weaning 90 d of age. Lambs were continued to graze as two groups on fescue-based pasture or grazing with creep feeding supplementation till marketing at 120 d. Weaning body weight (BW), average daily gain (ADG), and post-weaning growth weight were significantly (P < 0.05) greater than control 24.0 kg, 226 g/d, and 28.0 kg for treatment group compared with control group at 21.3 kg, 196 g/d, and 25.3 kg, respectively. However, AGD was not significantly increased during the post-weaning creep supplementary feeding period. The ultrasound scanned carcass traits increase in creep feeding over control lambs at weaning and post-weaning measurements (Figure 1). The average ultrasound scanned back fat depth, loineye muscle depth, muscle width, and loineye muscle area were 2.2 mm, 17.9 mm, 45.6 mm and 5.8 cm2 at weaning age of 90 d; and 2.6 mm, 20.9 mm, 48.0 mm, and 7.0 cm2 at 120 d, respectively. The correlative associations (Table 1) between carcass traits and lamb BW, such as loineye muscle depth (LED), loineye muscle width (LEW), loineye muscle depth (LED) and loineye muscle area (LEA), and LEA were significantly improved (P < 0.05) with increased BW. However, there was no difference in these traits due to treatment except backfat depth, which was significantly higher for treatment and females. Creep supplementary feeding lambs during pre-weaning has increased ADG and weaning weight; therefore, will enhance market values of organically raised lambs. The results indicate that USS technique is worthy of application in meat lamb selection, post-weaning performance and market premium prediction.
PSX-27 Growth performance and immune response dynamics in weaned lambs with subclinical Haemonchus contortus parasite infection
Authors: Jawad Hamza , Gellatly Desiree , Lei Yaogeng , Osonowo Olufemi , Gilleard John S , Miar Jounes , Manafiazar Ghader , Thompson Sean
Published: September 2024

Parasite infections, particularly from Haemonchus contortus, hinder sheep production in Canada by reducing weight gain and immunity. Current diagnosis and treatment methods rely on observing symptoms and the blind administration of anthelmintic drugs, resulting in escalating costs and the development of drug-resistant parasites. This study aimed to identify the exact time-point when subclinical H. contortus parasite infection affects growth performance and triggers an immune response. A total of 60 Rideau Arcott ewe lambs (~7-8 mo old), confirmed to be parasite-free, were randomly assigned in a 2 x 2 factorial design assessing inoculation treatment (TRT): oral inoculation (IN) with a solution containing 5,000 L3 strain of H. contortus or sham inoculation (CT) using water solution as control; and drench (DRENCH) administration: oral drench (D), 28-days post-inoculation, with a combination of 0.08% ivermectin solution (200 mcg per kg of BW; Durvet®) and 10% oral suspension of fenbendazole (2.5 mL per 50 kg of BW; Safe-guard®), or water solution (non-drenched, ND), resulting in four treatment groups: IN-D, IN-ND, CT-D, and CT-ND (n=15/treatment). Lambs were equally assigned to four feedlot pens (two replicates/treatment) for 57 days (d) with ad libitum access to a grain-based total mixed ration and water. Animals were individually weighed (BW) and blood sampled on days -1 and 0 (baseline), as well as on days 7, 21, 28, 35, 42, 56, and 57 post-inoculations (DAY); average daily gain (ADG) was calculated for the entire experimental period. White blood cells count (WBC) was used as an indicator of infection and red blood cell count (RBC) as indicator of anemia. Data was analyzed using a mixed-effects model including TRT, DRENCH, DAY (and their interactions) as fixed effects. Overall, CT lambs were heavier (TRT effect; P < 0.05) and had a tendency of greater (TRT effect; P = 0.08) ADG than IN lambs. The IN lambs had a tendency of greater (TRT*DAY; P = 0.07) WBC on d 7 than CT lambs. Additionally, IN-ND had lower (TRT*DRENCH; P < 0.05) WBC than IN-D lambs (1.9 and 2.0 ± 0.042 x 109/L, respectively). A significant (TRT*DRENCH*DAY; P < 0.01) interaction was found on RBC. The CT-D had lower (P < 0.05) RBC on d 7 and greater (P < 0.05) on d 28, 35, 42, and 57 than IN-ND as well as on d 28 than IN-D. Furthermore, CT-ND had greater (P < 0.05) RBC on d 21, 28 and 35 than IN-D and from d 21 to 57 than IN-ND. The IN-D had greater (P < 0.01) RBC from d 35 to 57 than IN-ND. These findings suggest compromised growth in both drenched and non-drenched infected groups. Infection slightly peaked in the infected lambs on d 7 post-inoculation, but drench administration was effective at mitigating overall infection by day 21 and the anemia by day 35.