bluuebunny/crossref_metadata_2025 huggingface dataset:
59 Feeding behavior in divergent residual enteric methane emissions steers during the backgrounding and finishing phases
Authors: de Vargas Juan J , Manriquez Diego , Swenson Maya , Carvalho Pedro H V , Stackhouse-Lawson Kimberly R , Place Sara E
Published: September 2024

Enteric methane (CH4) is produced during the anaerobic fermentation of organic matter and represents an energy loss for ruminants. Diet and animal characteristics mainly determine CH4 emissions. However, there is limited information regarding the relationship between feeding behavior and CH4 emissions in growing steers consuming different diets. This experiment aimed to evaluate the feeding behavior of growing steers with divergent residual methane emissions (RCH4) during the backgrounding and finishing phases. Two hypotheses were evaluated: 1) the steers would not change the initial RCH4 classification when moving from backgrounding to finishing phases, and 2) steers with divergent RCH4 would show different feeding behavior. Angus steers (n = 60) were placed in two pens and were classified as high, medium, and low RCH4 during both phases. During the backgrounding phase, steers [209 ± 26 kg of initial body weight (BW)] were fed a total mixed ratio (TMR) with 46% neutral detergent fiber (NDF) and 0.86 Mcal/kg DM of net energy of gain (NEg) for 60 d. During the finishing phase, steers (517 ± 40 kg of initial BW) were fed a TMR with 16.8% NDF and 1.37 Mcal/kg DM of NEg for 80 d. Feed intake and gas flux were determined daily using Smartfeed and Greenfeed technology. Steers were weighed every 2 wk during each phase to determine average daily gain (ADG). The number of meals (NM), meal size (MS), time per meal (TM), intervals between meals (IM), and intake rate (IR) were calculated using 5 min as a meal criterion. Individual RCH4 classification rank during the backgrounding and finishing phases was analyzed using a chi-square test. Feeding behavior was analyzed using a mixed model with RCH4 classification and animal as fixed and random effects, respectively. No relation (P = 0.5) existed between individual RCH4 classification during the backgrounding and the subsequent RCH4 classification during the finishing phase. In either phase, feed intake or ADG was not different (P > 0.05) among divergent RCH4 groups. Feeding behavior was not different (P > 0.05) among RCH4 groups during the backgrounding phase, but MS and TM were greater (P < 0.05) in steers with high RCH4 during the finishing phase. Steers classified as low RCH4 showed less CO2 and CH4 production and less O2 consumption than medium and high RCH4 in either phase. In conclusion, growing steers were re-ranked according to the RCH4 classification during the backgrounding and finishing phases. Animal performance was not related to RCH4 classification. However, steers with decreased RCH4 showed less MS during the finishing phase. Also, CO2 and CH4 were less in low RCH4 steers during both phases. Further work should be conducted to recognize differences in fermentation and metabolism of lower RCH4 steers for developing selection and management interventions.
62 Relationship between feed efficiency and reproductive measures in beef heifers
Authors: Hall John B , Bloomsburg Maggie K , Sprinkle Jim E , Stratton Sidney E , Glaze James B
Published: September 2024

The objective of this study was to determine the influence of residual feed intake (RFI) classification on reproductive measures and pregnancy rates in beef heifers. During an 8-yr period, 1,090 heifers were tested for feed efficiency in 70-d trials using a GrowSafe system. Heifers had ad libitum access to water and diets designed to meet NRC requirements for 0.90 kg/d gain. Diets, fed as a total mixed ration, were 85% forage and 15% concentrate which included vitamin and mineral supplements. Heifers were weighed at weaning, the beginning of the RFI trial, at yearling, end of the RFI trial and at breeding. Residual feed intake values were calculated, and heifers were grouped into RFI categories of Average (AVG), Efficient (EFF) or Inefficient (INE). At 13 mo of age, reproductive tract scores (RTS) and pelvic areas were measured. In 5 of the years, heifers (n = 487) also had antral follicle counts (AFC) determined via transrectal ultrasonography. Heifers were estrous synchronized and artificially inseminated (AI) with AI bulls balanced across efficiency categories. Estrus response to synchronization was recorded at fixed-time AI. Pregnancy status and fetal age were determined via transrectal ultrasonography at 60 d and 100 d after AI. Records from 1,078 heifers were used in the analysis (AVG = 428; EFF = 317; INE = 333). Dry matter intake (DMI), body weights, average daily gain (ADG), RTS, and AFC were analyzed using Mixed procedures in SAS. Estrus response and pregnancy rates were evaluated using Logistic procedures. Differences among RFI categories (P < 0.0001) were a result of differences in DMI (P < 0.001) averaging 12.5, 11.5, and 10.2 kg/d (SE = 0.44 kg/d) for INE, AVG and EFF heifers, respectively. In addition, ADG was greater (P < 0.05) for AVG compared with INE heifers. Prior to RFI classification, birth weight was less (P < 0.03) in EFF compared with AVG heifers, and weaning weight (P < 0.01) greater in EFF compared with AVG or INE heifers. However, yearling weight and breeding weight were similar (P = 0.60) across RFI category. Indicators of reproductive development, RTS (P = 0.24) and AFC (P = 0.79) were not different among RFI category. Estrus response to synchronization increased (P < 0.04) for INE (77.3%) compared with AVG (69.1%) or EFF (70.1%) heifers. However, fixed-time AI and final pregnancy rates were similar (P > 0.69) among RFI categories and averaged 54.7%, 54.5%, 52.7% and 89.7%, 88.8%, 87.8% for AVG, EFF and INE heifers, respectively. In conclusion, differences in feed efficiency as indicated by RFI had limited influence on measures of reproductive development in beef heifers and did not alter pregnancy rates. Therefore, placing emphasis on feed efficiency in developing beef heifers should not alter reproductive performance.
65 Metagenomic analysis of ensiled grocery food waste
Authors: Bumunang Emmanuel , Garcia-Rodriguez Vicky , Bukola Rhoda , Silva-Castro Vinicius , Zaheer Rahat , McAllister Tim A , Stanford Kim
Published: September 2024

Vegetables and fruits are the main sources of plant fiber, minerals, and vitamins essential for human health. However, commercially manufactured foods which are not consumed end up in landfills and contribute to economic losses as well as to methane emissions, a global warming gas. Besides recycling food waste (FW) as compost to reduce unsaleable vegetables and fruits intended for landfill, it can be ensiled as an alternative source for a sustainable livestock feed. Metagenomics is the analysis of genetic material purified directly from environmental samples by sequencing and enables taxonomic identification of the microbial communities present. This study aimed to evaluate the silage produced with different mixtures (fruit, vegetables, bread, and bakery products) of FW after 60 d to evaluate microbial community and functional diversity. The FW was ground to a particle size of 1 cm2 and three treatments in duplicates were obtained: control (refrigerated), sundried (exposed to sun) and passive-dried (inside the building). The DNA of the ensiled FW was extracted for two metagenomic sequencing approaches; specific regions sequencing including 16S rRNA (bacterial diversity), 18S rRNA (species differences in eukaryotes), internal transcribed spacer (ITS; for fungal classification) and shotgun sequencing. Specific coding region sequencing is more precise while shotgun sequencing can better identify the most abundant organisms. Therefore, we are using these two methods for comparative analysis and to enable us to capture the entire microbial community. Analysis of the metagenomic data are ongoing with the intention to characterize potential pathogenic bacteria and antimicrobial resistance genes within the ensiled FW to confirm that the ensiled FW is safe to feed to cattle. We are awaiting data for specific region sequencing. Overall, we expect to confirm if this approach is useful for silage analysis.
72 Environmental impacts associated with the removal of productivity enhancing technologies from three different post-weaning feed management strategies in Saskatchewan: A case study
Authors: Fortier Sydney , McAllister Tim A , Fulawka Deanne , Legesse Getahun , Mengistu Genet , Aboagye Isaac , Lardner H (Bart) A , Tenuta Mario , Ominski Kim H
Published: September 2024

The purpose of this research was to examine the use of productivity enhancing technologies (PETs) and post-weaning management on the environmental impacts of beef steers in western Canada. The PETs considered in the current study included ionophores (i.e., monensin, 33 ppm) and hormone implants (i.e., Ralgro, 36 mg zeranol). The production management systems considered were direct finishing (Heavy), confined backgrounding prior to finishing (Medium), and confined and pasture-based backgrounding prior to finishing (Light). The objectives were to model and compare environmental outcomes [greenhouse gas emissions (GHG), ammonia (NH3) emissions, land requirements and water use] using a whole-farm perspective and better understand the environmental footprint of the Canadian beef industry. Compared with natural steers, PETs led to a 10 to 13% reduction in GHG emissions (CO2e kgּ boneless beef-1), a 10 to 32% decrease in NH3 emissions (kg NH3ּּ kg boneless beef-1), a 9 to 22% reduction in land use (haּ kg boneless beef-1) and 12 to 25% decrease in water (m3ּ kg boneless beef-1) use. Direct finishing compared with backgrounded, and 2-stage backgrounded steers reduced GHG by 32% and 39% kg CO2eּ kg boneless beef-1, NH3 emissions by 36% and 52% kg NH3ּ kg boneless beef-1, land requirements by 25% and 73% haּ kg boneless beef-1 and water use by 18% and 51% m3ּ kg boneless beef-1, respectively. Varying post-weaning strategies allows producers to value-add (additional weight through backgrounding) and maximize the use of available feed (grazing). The full environmental impacts of removal of PETs from Canadian beef production must consider a whole-systems approach including economic viability, ecosystem services, as well as consumer demand and social acceptance.
70 Evaluation of nutritional monitoring techniques for beef cattle grazing Texas gulf coast rangelands
Authors: Dudak Jessica , Rodrigues Barbara , Carey Camille , Winkler Taylor , McCoy Christopher , Tolleson Douglas R
Published: September 2024

Projecting grazing cattle performance based on forage quality is still a challenge for nutritional modeling and monitoring for livestock producers and researchers. Therefore, our objective was to evaluate the effectiveness of fecal near infrared reflectance spectroscopy (FNIRS) in conjunction with the Nutritional Balance Analyzer (Nutbal) system as a grazing cattle nutrition tool. Commercially available FNIRS diet quality calibrations derived from diet chemistry and fecal spectra representing a diverse set of rangeland and forage types across the U.S. have successfully predicted cattle performance in multiple environments, but there have been location specific instances of poor results. This study evaluated diet crude protein (CP) and digestible organic matter (DOM) and subsequent projection of body condition/body weight change of rangeland beef cattle grazing three ranches in the gulf coast region of Texas from October 2022 to October 2023. Cattle used in this study ranged in age from 30 mo - old primiparous heifers to 78 mo - old mature cows maintained under a variety of management practices including different calving season (Spring or Fall), pasture rotation schedules, and supplementation with protein cubes or protein/ energy lick tubs. On each sampling date, a herd composite of 10 to 15 fresh individual fecal pats were collected to represent the pasture where cattle were currently grazing. Body condition scores (BCS) were recorded at each sampling event, every 4 to 6 wk. Projected body weight/BCS was derived from Nutbal. Differences in observed and predicted BCS were determined via paired T-test with significance at P < 0.05. The herd with the greatest agreement (75%) between observed and predicted BCS (P > 0.1), had BCS means of 5.15 ± 0.07 and 5.12 ± 0.14, respectively. In contrast, the herd with the least agreement (36%; P < 0.01) had an observed BCS mean of 5.78 ± 0.10 and a mean FNIRS/Nutbal predicted BCS of 6.28 ±0.14. In conclusion, the FNIRS/Nutbal system as currently applied was able to satisfactorily predict grazing cattle herd performance in some ranches/herds of the gulf coast region. However, further investigation is necessary to address and understand the factors contributing to specific instances of disagreement between observed and predicted BCS. This information will be used to improve the performance of the FNIRS/Nutbal system.
186 Evaluating the interaction between divergent genomic selection for heat stress tolerance in the F1 generation and in utero heat stress on piglet growth performance following weaning and transport
Authors: Hernandez Rick O , Brito Luiz F , Byrd MaryKate H , Musa Jacob , Tiezzi Francesco , Maltecca Christian , Johnson Jay S
Published: September 2024

In utero heat stress (IUHS) has long-term negative-effects on pigs during postnatal life. Specifically, IUHS pigs display greater stress responses following weaning and transport and have reduced growth performance among other issues. Although efforts have been made to mitigate IUHS through management and nutrition, the use of genomic selection to improve heat stress tolerance (TOL) in gestating sows and reduce the impacts of IUHS on developing offspring has not been extensively studied. Therefore, the study objective was to determine whether genomic selection for TOL or heat stress sensitivity (SEN) in F1 gilts would impact the postnatal growth performance of IUHS piglets following weaning and transport. We hypothesized that IUHS piglets derived from TOL gilts would have improved growth performance relative to IUHS piglets derived from SEN gilts, but that overall, IUHS piglets would have reduced growth performance when compared with IUTN piglets following weaning and transport. Twenty-eight TOL (n = 15) and SEN (n = 13) pregnant gilts were exposed to either thermoneutral (TN; 17 to 20ºC; n = 7 TOL and 6 SEN) or heat stress (HS; cycling 26 to 36ºC; n = 8 TOL and 7 SEN) conditions from d 6 to 70 of gestation, and then all gilts were exposed to TN conditions until farrowing. At weaning, mixed sex piglets were selected from each litter resulting in the following treatment combinations: TOL+ in utero thermoneutral (IUTN; n = 60), TOL+IUHS (n = 60), SEN+IUTN (n = 59), and SEN+IUHS (n = 58). Piglets were then transported for 12 h to simulate commercial conditions and then group housed in 40 nursery pens (n = 6 pigs/pen) for 5 wk. All pigs were fed a standard nursery diet containing primarily corn and soybean meal and feed and water were provided ad libitum. Body weights (BW) and feed disappearance were measured on d 1, 7, 14, 21, 28, and 35 post-weaning and transport and used to calculate average daily gain (ADG), average daily feed intake (ADFI), and Gain:Feed. Data were analyzed in R using a generalized linear mixed model with pen as the experimental unit for ADFI and Gain:Feed, and individual piglet was the experimental unit for BW and ADG. Overall, IUHS piglets had a reduction (P < 0.01) in ADG (6.3%), Gain:Feed (4.4%), and final BW (2.5%) when compared with IUTN piglets. Additionally, TOL piglets had an overall improvement (P < 0.01) in ADG (6.0%), ADFI (13.6%), and final BW (3.9%), but a decrease in Gain:Feed (5.8%) when compared with SEN piglets. No genomic by in utero treatment effects were observed with any comparison. In conclusion, IUHS had a negative impact and selection for TOL had a generally positive impact on postnatal growth performance, but genomic selection for TOL or SEN did not interact with IUHS or IUTN in the F1 generation.
454 Evaluating the effects of grazing native rangeland on enteric emissions
Authors: Husmann Aletta L , Moreno Elias R Velasquez , Brennan Jameson R , Smith Zachary K , Olson Kenneth , Blair Amanda , Ehlert Krista , Wang Tong , Leffler Joshua , Wafula Walter , Parsons Ira L , Dotts Hadley , Guarnido-Lopez Pablo , Tedeschi Luis O , Menendez Hector M
Published: September 2024

Understanding beef cattle enteric emissions on extensive western U.S. rangeland systems is critical for implementing sustainable grazing practices that reduce greenhouse gas (GHG) emissions. These practices must also improve livestock and plant productivity and climate resiliency while maintaining or reducing production costs. However, enteric emissions of grazing cattle under different stocking rates and grazing management strategies are largely unknown for western U.S. rangelands. Thus, our objective was to evaluate the differences in enteric emissions of stocker steers grazing native rangeland. Yearling Angus steers (n = 127) were stratified by initial body weight (BW) to six groups, then randomly assigned to one of six pastures grazed from June to September 2023 at the South Dakota State University Cottonwood Field Station (Cottonwood, SD) as part of a long-term stocking rate trial (80+ yr). Each pasture was equipped with a GreenFeed (C-Lock Inc, Rapid City, SD) pasture system to measure individual animal CH4 and CO2 emissions for continuous grazing (CG) and rotational grazing (RG) strategies in three stocking rates (Light, Moderate, and Heavy, 0.32, 0.40, and 0.72 animal unit months, respectively) in a 2 x 3 factorial design. Differences in enteric emissions among stocking rate and grazing strategy were analyzed using a linear mixed effects model in R, using the lme4 package, with animal as a random effect, and a post-hoc contrast among treatments was assessed using the lsmeans package. Steer initial and final BW were similar (P > 0.05) among treatments. For CH4 emissions, there was a significant interaction between stocking rate and grazing strategy (P < 0.05). Specifically, CH4 emissions for moderate-RG (195 ± 4.3 g/d) were less than those from heavy-CG (221 ± 4.5 g/d) and light-RG (221 ± 4.7 g/d) over the study period (P < 0.05). For CO2 emissions, light-CG steers respired greater CO2 emissions (6892 ± 101 g/d) than heavy-RG (6398 ± 107 g/d; P < 0.05). All other treatment lsmeans were similar (P > 0.05) and intermediate to these treatment effects. The assessment of GHG emission values for cattle grazing native rangeland is essential for informing climate mitigation strategies, improving animal efficiency, and understanding changes in GHG emissions over production phases and across animal classes.
94 Associative effects of two potent anti-methanogenic Moringa oleifera accessions mixed at various proportions on in vitro rumen fermentation and methane inhibition
Authors: Zeru Addisu Endalew , Imamu Abubeker Hassen , Apostolides Zeno , Tjelele Julius
Published: September 2024

Moringa is an important anti-methanogenic plant with a potential to develop as multipurpose feed additives. Previous studies identified two potent accessions (accession 07633 designated as A3 and accession collected from Pretoria designated as A11) with high methane (CH4) inhibition characteristics. Two metabolite ion features (MIFs) 4.44_609.1462 and MIF 4.53_433.1112 were identified as bioactive MIFs associated with greater methane inhibition in Moringa accession A3 and A11, respectively. Two separate studies were conducted with an aim to name the MIF associated with methane inhibition and evaluate the benefit of mixing plant extract from A3 and A11 in different proportions to exploit their additive or synergistic effect in inhibiting CH4 emission. In study 1, software and online tools such as MS-DIAl, MS-FINDER, and the mass bank database were used to identify the MIF 4.44_609.1462 and MIF 4.53_433.1112, and the two MIFs were tentatively named as Hesperidin and Isovitexin, respectively (Figure 1). In study 2, the Moringa plant extracts from A3 and A11 were mixed in the following proportion A3100:A110, A380:A1120, A360:A1140, A350:A1150, A340:A1160, A320:A1180, and A30:A11100 proportions (A3:A11), and applied at a rate 50 mg/kg DM of Eragrostis curvula hay incubated in an Incoshake incubator to determine their effect on in vitro gas production and CH4, and in vitro organic matter digestibility (IVOMD) of the hay. In each incubation run, the sole or a mixture of the Moringa plant extract treatments were added to the test feed and incubated in 125 mL serum bottles with four replications per treatment, and the incubation was repeated for three runs. A Chi–square (☐2) test were used to determine the presence of an associative effect for mixtures combined at different proportion. Generally, the mixture resulted in less (P < 0.05) CH4 volume, slightly improved or no effect on IVOMD, propionate concentration decreased acetate while increasing propionate concentration, with higher CH4 inhibition, and % CH4 inhibition was significantly greater when the two accessions were mixed in 50% proportion (Figure 2). Specifically, associative effects were recorded when the two accessions are mixed in 50% proportion in terms of greater CH4 inhibition, propionic acid concentration and total volatile fatty acid production (TVFA), as well as reduction in CH4 per unit TVFA and C2:C3 ratio (Table 1). Therefore a 50% binary cocktail of M. oleifera accession A3 and A11 (A350:A1150) plant extracts can be used as feed additive for CH4 inhibition without affecting the feed fermentation adversely when compared with the sole accession leaf extracts or other proportions of binary cocktails. Detailed mechanisms of action, however, need to be confirmed.
92 Utilizing buccal swabs as a substitute for ruminal fluid for characterizing the microbiome of Angus bulls
Authors: Dycus Madison M , Lamichhane Utsav , Lourenco Jeferson M
Published: September 2024

Gastrointestinal tract metagenomic sequencing has unveiled rumen microbiota influences on animal production and efficiency; however, ability to analyze the rumen non-invasively, amply, and cost-effectively is restricted, as specialized equipment is required to obtain ruminal samples. This study aimed to employ buccal swabs as a substitute for rumen sampling by exploiting rumination. Ruminal fluid contents and buccal swabs were collected from registered Angus bulls (n = 541) produced by five commercial feed testing centers located in Georgia, Iowa, and Montana. DNA was extracted and the 16S rRNA gene was sequenced to determine differences and similarities in microbial composition between the two sample types. Sequencing data were analyzed for taxonomic classification, and calculation of alpha and beta diversity indices. Microbial evenness (Pielou’s index), richness (number of amplicon sequence variants), and diversity (Shannon index) were all significantly greater (P < 0.01) in the rumen, indicating distinct differences in alpha diversity between sample type. Beta diversity analysis (unweighted UniFrac distances) revealed the taxonomic profile of each sample type was also explicitly different (P < 0.01). Both sample types were dominated by genera that are common members of each environment: Streptococcus in oral, and Prevotella in ruminal samples, and only three of the 30 most abundant genera for each sample type were shared in both environments. At the species level, only 33.1% out of 4,323 total microbial species occurred in both rumen and oral environments. Collectively, these results suggest substantial differences between oral and ruminal compartments, indicating that using the oral microbiome as a substitute for the rumen microbiome may not be a feasible strategy. Further research should be conducted to control for factors that could impact oral to rumen reflection, such as time since last feeding, rumination patterns, and water intake.
132 Evaluation of a phytogenic feed additive containing garlic, clove, and capsicum oleoresin on the health and performance of newly received, high-risk calves
Authors: Wilson Blake K , Owen Natally , Heldt Jeff S
Published: September 2024

Abstract:

The objective of this experiment was to evaluate the effects of a phytogenic feed additive (PHYT) on the health and performance of newly-received, high-risk calves. Auction market derived crossbred beef steers and bulls (n = 712; initial body weight; BW = 239 ± 6.8 kg) were stratified by sex, blocked by BW, and randomly allocated to experimental treatments (n = 9 pens per treatment; n = 24 to 29 calves per pen). Experimental treatments included: a control diet (CON), 250 mg · steer⁻¹ · d⁻¹ of PHYT (PHYT250), or 500 mg · steer ⁻¹ · d⁻¹ of PHYT (PHYT500). Pen served as the experimental unit for all dependent variables. Contrasts were performed for PHYT inclusion (PHYT250 and PHYT500 vs. CON). No differences in BW existed between treatments throughout the experiment (P ≥ 0.20; PHYT vs. CON P ≥ 0.11). In the overall model, no differences (P ≥ 0.23) in average daily gain (ADG) existed between CON, PHYT250, or PHYT500. However, when comparing PHTY to the CON, ADG tended to be less in the calves receiving CON from d 0 through d 14 (P = 0.09). No differences in dry matter intake (DMI) existed between treatments throughout the experiment (P ≥ 0.27; PHYT vs. CON P ≥ 0.13). While there was no difference in gain to feed (G:F) in the overall model (P ≥ 0.26), the tendency observed for a difference in ADG from d 0 through d 14 did result in a similar tendency for G:F across the same interval when comparing PHYT to the CON (PHYT vs. CON P ≥ 0.10). A difference was observed in the percentage of steers treated once for bovine respiratory disease (BRD; P = 0.02), with CON being treated more frequently than PHYT500, while PHYT250 was intermediate and similar to both CON and PHYT500. When comparing PHYT to the CON, there was a decrease in the percentage of steers receiving PHYT to be treated once for BRD (P = 0.01). However, there were no differences in either the percentage of steers treated twice for BRD or the in the percentage of total BRD treatments administered (P ≥ 0.29; PHYT vs. CON P ≥ 0.14). The mortality percentage and the percentage of steers removed from the study were not different (P ≥ 0.16; PHYT vs. CON P ≥ 0.14); however, there tended to be more combined mortalities and removals for steers receiving PHYT than the CON (P = 0.08; PHYT vs. CON P = 0.09), with PHYT500 and CON tending to be different, and PHYT250 being intermediate and similar to both PHYT500 and CON. In summary, PHYT did not impact overall performance, but did reduce initial antimicrobial treatments for BRD.
125 Could yeast derivatives change beef cattle water intake in different scenarios?
Authors: Reis William , Bonato Melina A , Pacheco Rodrigo , de Paula Nelcino F , Souza Fernando Augusto
Published: September 2024

Adequate water intake is linked to greater dry matter intake, heat loss, and productivity. To measure the water intake of beef cattle reared in groups, two experiments were carried out in Brazil (South East/Middle East) using water throughs coupled with scales (Intergado, Betim, Brazil) and RFID individual identification systems, allowing the recording of individual water intake of animals. In experiment 1, young bulls (n = 96; 105 d on feed - feedlot) were randomly assigned to four treatments: 1) Control, no yeast derivative; 2) AY – 7 g·animal⁻¹·d⁻¹, Autolyzed Yeast grown on sugarcane molasses (RumenYeast, ICC, Brazil); 3) YM – 3 g·animal⁻¹·d⁻¹, yeast rich in soluble Yeast Metabolites; 4) YB – 5 g·animal⁻¹·d⁻¹, Yeast Blend (live Yeast plus autolyzed Yeast). Diets (adaptation, growing, and finishing) x treatments were treated as fixed effects on the complete randomized design. In experiment 2, backgrounding bull calves (n = 32) reared on grazing and 710 g/d of protein supplements (90 d) were randomly assigned to two treatments: 1) Control, no yeast derivative; 2) AY – 7 g·animal⁻¹·d⁻¹, Autolyzed Yeast (RumenYeast), the means were subjected to ANOVA analyses. In both experiments, additives were inserted into the diet (mineral premix or supplement), animals were the experimental unit, and differences were declared significant at P < 0.05. Yeast derivatives increased (P < 0.05) water intake in both experiments (Figure 1). The average increment in water intake (L·animal⁻¹·d⁻¹ was 13.9%. Interestingly, the increment in relation to control was noted for all yeast derivatives and scenarios covered by the experiments (feedlot adaptation diet, feedlot growing diet, feedlot finishing diet, and grazing system). Until now, there seems to be no literature explanation for our findings. However, these results could help to explain the positive effects of yeast derivatives on rumen pH, protein microbial flow, and thermal stress since greater water intake increases the passage rate of rumen fluid and body heat loss. Statistical correlations may not be understood as a cause-consequence link. However, when dealing with a new question, correlations may give us a path to go on and investigate. Malheiros et al. (2023) noted a negative correlation between water intake and rumen dimethylamine. Autolyzed yeast can strongly decrease the concentration of rumen methylamines in cows facing subacute acidosis (Humer et al., 2018). Niacin metabolism should also be investigated since its supplementation enhances cows’ blood niacin levels and water intake. Yeast derivatives are rich in niacin, and autolyzed yeast supplementation can increase blood niacin and body heat loss during summer (Dias et al., 2018), probably increasing water need. In conclusion, yeast derivatives increased the water intake of beef cattle, and this finding adds to the understanding of how yeast derivatives supplementation benefits ruminants.
197 Hepatic mRNA expression of innate and adaptive immune genes in beef steers with divergent residual body weight gain
Authors: Ologunagba Deborah , Idowu Modoluwamu , Taiwo Godstime A , Sidney Taylor S , Treon Emily , Eichie Francisca , Ogunade Ibukun M
Published: September 2024

Immune function has a pivotal role in dictating the overall health and productivity of cattle. In a proficient immune system, the liver assumes an integral function in detoxification and metabolic processes and contributes substantially to overall production and immunity. In this study, we evaluated the hepatic mRNA expression of genes involved in innate and adaptive immunity in crossbred beef steers with positive or negative residual body weight (BW) gain (RADG). Positive-RADG beef steers (n = 8; RADG = 0.76 kg/d) and negative-RADG beef steers (n = 8; RADG = -0.64 kg/d) were identified from a group of 108 growing crossbred beef steers (average BW = 286 ± 380kg) after a 56-d performance testing period. At the end of the 56-d period, liver tissue samples were collected from the beef steers for RNA extraction and cDNA synthesis. The mRNA expression of 84 genes involved in innate and adaptive immunity were analyzed using pathway-focused PCR-based arrays. The mRNA expression of genes with false discovery rate-adjusted P-values (FDR) ≤ 0.05 and absolute fold change (FC) ≥ 1.2 were determined to be differentially expressed. Out of the 84 genes analyzed, four genes [interleukin (IL)-2, MYD88, CD-80, NFkB-1] were differentially expressed and were all upregulated in positive compared with negative-RADG beef steers. Gene ontology pathway enrichment analysis of the differentially expressed genes revealed that pathways related to positive regulation of IL-17 production, cellular response to lipopolysaccharide, and positive regulation of lymphocyte activation were enriched in the positive-RADG steers (P ≤ 0.05). In conclusion, our study revealed that positive-RADG beef steers had increased expression of genes and pathways involved in pathogen recognition and initiation of responses to effectively fight off infections while mitigating excess inflammatory reactions compared with negative-RADG steers, which might explain, in part, the improved feed efficiency of these beef animals
196 Metabolic characteristics and truly digestible nutrient supply to dairy cows: 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 study was to investigate effects of oat varieties and types (feed type vs. milling type) on metabolic characteristics, truly digestible nutrient supply, and feed milk value (FMV). Twelve samples [4 varieties (Arborg, Haymaker, Nasser, Summit) × 3 harvested years (2018, 2019, 2020)] were used in this study. The DVE/OEB system and NRC-2001 system were applied to evaluate these parameters. The experiment design was RCBD design (oat varieties as a fixed effect and harvested year as a random block effect). MIXED procedure model of SAS 9.4 was used for statistical analysis, and significance was declared at P < 0.05 and tendency at 0.05 ≤ P < 0.1. Based on the DVE/OEB system, results showed that microbial protein synthesized in the rumen based on available nitrogen (MREN, g/kg DM), microbial protein synthesized in the rumen based on available energy (MREE, g/kg DM), truly absorbed microbial protein in the small intestine (DVME, g/kg DM), truly digested protein in the small intestine (DVE, g/kg DM) and feed milk value (FMV, kg milk /kg feed) of Nasser oat were least in these four varieties although Nasser oat had no significant differences on MREN content with Arborg and Summit oat. Nasser oat had highest endogenous protein loss (ENDP, g/kg DM) and undigested dry matter (UDM, g/kg DM) in these four oat varieties (P < 0.05). Nasser oat also had the largest degraded protein balance (OEB, g/kg DM) value compared with Arborg, Haymaker and Summit oat, and all the OEB values were positive indicating having potential N losses from rumen. There were significant differences in the MREE, DVME, ENDP, UDM, DVE, OEB and FMV between feed oat and milling oat (P < 0.05), and feed oat had larger OEB values than milling oat. Based on the NRC-2001 model, oat varieties had significant impact on microbial protein synthesized in the rumen based on available energy (MCPTDN, g/kg DM), microbial protein synthesized in the rumen based on available protein (MCPRDPNRC, g/kg DM) and truly absorbed microbial protein in the small intestine (AMCP, g/kg DM; P < 0.05). Haymaker oat had higher metabolizable protein (MP) and FMV than Summit oat (P < 0.05), and had similar MP and FMV with Arborg and Nasser oat. As for the oat types, no significant differences were found on all the characteristics between feed type and milling type, and feed oat had better FMV compared with milling oat.
246 The influence of supplemental alfalfa pellet levels on beef cattle grazing winter foothill rangelands
Authors: Hamilton Thomas , Wyffels Sam , Kluth Janessa A , Peterson Jeremiah , Davis Noah G , DelCurto Timothy
Published: September 2024

This study evaluated the influences of graded levels of supplemental alfalfa pellets on beef cattle performance during mid-late gestation of multiparous beef cows. Angus based bred cows (n = 120) were used in an 84-d winter grazing experiment that took place on native foothill rangelands. Cattle were stratified by age and body condition and, within stratum, randomly assigned to one of four treatments: 1) no supplement, 2) cows fed 0.76 kg×d-1 supplement, 3) cows fed 1.52 kgּ d-1 supplement, and 4) cows fed 2.27 kgּ d-1 supplement. Protein supplement fed was a 18% CP alfalfa pellet. Cows were gathered 3-times weekly and provided supplement on a replicated pen basis. Supplement was provided through d 84 and then cows were introduced to a common diet until d 203. Performance data was analyzed as a completely randomized design with linear and quadratic contrasts used for mean separation (reps = 5; n = 6). Body weights (BW) and body condition score (BCS) were recorded every 28-d period throughout the study and at 203 d post calving, calf BW were obtained at birth. A treatment × period interaction was detected for BW change (P < 0.01), where increasing protein supplementation resulted in linear increase in BW gains (P < 0.01) relative to the control treatment, with BW change ranging from -23.6 kg for control cattle to 14.64 kg in the cattle fed the high level of supplementation. BCS change also exhibited a linear response for all four BW periods (P < 0.01) where cattle from the control treatment expressed a -0.49 loss of BCS over the duration of the study while high supplemented cattle-maintained condition only losing 0.02. No difference in calf BW was observed between the control and any supplemental treatments (P = 0.30) with an overall BW average of 38.37 kg. In conclusion, increasing levels of supplemental protein resulted in linear improvements of both BW and BCS of grazing beef cattle during the winter. These differences observed were then maintained throughout d 203 after all cattle were introduced to a common management regime. Birth weights of calves were not affected by the level of protein supplementation.
257 Total degradable and undegradable protein and carbohydrate supply to dairy cows from the newly developed blended fat stimulated feed product in comparison with commercial protein and energy feeds
Authors: Ihsan Umair , Prates Luciana , Newkirk Rex N , Lardner H (Bart) A , Rodríguez Espinosa María E , Yu Peiqiang
Published: September 2024

The objectives of this study were to determine total rumen degradable and undegradable protein and carbohydrate supply to dairy cows from the newly developed value-added blended fat stimulated feed product (BFSFP) in comparison with commercial protein and energy feeds. The new blended fat stimulated feed products with three-batch samples (BFSFP1, BFSFP2, BFSFP3) were developed. Barley grain samples (n = 3) and canola meal samples (n = 3) were obtained from Canadian Feed Research Center. Total rumen degradable and undegradable protein and carbohydrate supply to dairy cows were determined using the updated Cornell Net Carbohydrate and Protein System. The treatment design was a one-way structure. The experimental design was a CRD with feed treatments as a fixed effect. The data were analyzed using the Mixed model procedure of SAS. Tukey method was used for mean separation. The results showed that compared with commercially available energy-rich and protein-rich feeds, the BFSFP had less (P < 0.05) total degradable protein supply to dairy cows (TRDP: 17.0 vs. 23.9, 7.4%DM) and total undegradable protein supply (TRUP: 13.9 vs. 17.8, 5.1%DM) than canola meal and greater than barley grain. For carbohydrate degradable and undegradable supply to dairy cows, the results showed that the BFSFP had greater (P < 0.05) total degradable carbohydrate supply to dairy cows (TRUC) than canola meal and less than barley grain (TRDC: 26.0 vs. 20.8, 56.6%DM, respectively). The BFSFP had greater total undegradable carbohydrate supply (TRUC) than canola meal and barley grain (supply (TRUC: 30.3 vs. 28.7, 26.6%DM, respectively, P = 0.09).
248 Impacts of sprouted barley on the performance and carcass traits in finishing Angus steers
Authors: Crump Zachary C , Alberto Anthony F , Brown Bailee , Roholt Bryce W , Okamoto Lillian , Thornton-Kurth Kara J , Spurling Ryan A , Ward Robert , Blackett Brady , Harding Rob , Ranathunga Sanjeewa
Published: September 2024

The growing population, coupled with unpredictable weather patterns, demands that livestock producers think innovatively to improve sustainability. Producers are interested in innovative practices and technology, such as controlled environment farming to sprout cereal grains that can be fed to livestock. However, little research has determined the effects of giving these feeds to finishing beef steers. As such, Angus steers (n = 60) were stratified by body weight (BW; 385 kg ± 10.3) to receive two different diets (n = 30/diet). The control (CON) diet was a traditional finishing ration for the region, whereas the other included 20% (dry matter; DM) sprouted barley (SB) in place of corn silage. Animals were fed for 128 d in pens with Vytelle units to measure intake and feeding behavior. On d 0, 30, 60, 90, and 128 BW, ruminal fluid, and ultrasound measurements were taken. Liver score (LS) and typical carcass data were collected from a commercial harvest facility. Statistical analyses used the MIXED procedure of SAS to assess the main effect of diet for all measurements collected over time. Dry matter intake (DMI), feed efficiency (gain to feed; G:F), ruminal volatile fatty acid (VFA) composition, and feeding behavior were run as repeated measures. No differences (P = 0.37) in BW gain were found between steers receiving different diets, but steers receiving SB had decreased (P < 0.0001) DMI throughout the trial compared with CON. This decrease in DMI drove a diet × day effect (P = 0.004) for G:F such that SB had increased (P ≤ 0.04) G:F on d 0 and 60, but no effect (P ≥ 0.52) was observed at d 90 or 128. Steers receiving the CON diet spent more (P < 0.0001) time at the feed bunk than those receiving the SB diet, which supports the observation that steers receiving the CON had an increased DMI. Ruminal pH, total VFA concentration, acetate:propionate, percent propionate, and percent butyrate were each impacted by diet × day (P ≤ 0.007). The only carcass trait impacted by diet was yield grade (YG), where steers receiving the SB diet had an increased (P < 0.03) YG compared with CON. These results demonstrate that replacing corn silage with SB in the ration of finishing steers has some effect on ruminal VFA composition, DMI, G:F, and USDAYG. Due to decreased DMI, SB steers had increased feed efficiency which could potentially have a positive economic impact for producers. However, additional analysis is needed to further determine if these systems are economically viable in a production setting.
247 Interaction between colostrum and milk replacer supply on growth, development and fecal consistency of dairy surplus calves
Authors: Munera Juanita Echeverry , Marti Sonia , Steele Michael A , Devant Maria , Martín-Tereso Javier , Leal Leonel N
Published: September 2024

This study examined the interactions between early life nutrition strategies and their impact on growth, development, and fecal consistency in surplus bull calves. Holstein-Friesian bull calves [n = 120; body weight (BW) = 43.1±3.56 kg] were enrolled. In the first 12 h after birth, calves were fed either 2 L (100 g of IgG) or 6L (300 g of IgG) of colostrum replacer (CR) to obtain either failure (F) or successful (S) transfer of passive immunity, respectively. Upon arrival at the facility, serum IgG concentrations were measured; therefore, F and S calves were identified accordingly and randomly assigned to one of two milk replacer (MR) feeding schemes: Moderate (Mod; ~8 L) or Low (Low; ~4 L). In total, there were 4 treatments resulting from the 2 × 2 factorial design: F-Mod, F-Low, S-Mod, S-Low (n = 30/treatment). Calves were individually housed and fed twice daily until d 42, gradually weaned until d 56, and had free access to straw and water during the study. On d 22, a calf pelleted starter was offered. To evaluate organ and gastroinstetinal tract development, 10 calves/treatment were euthanized at 84 d of age. Other measurements include weekly BW, daily intakes, and daily fecal score until d 21. Data were analyzed by PROC MIXED in SAS accounting for the fixed effects of block, CR, MR, and time, and their interaction. Time entered the model as a repeated statement, and initial BW was used as a covariable when appropriate. Initial BW was not different across treatments, whereas serum IgG was greater in S calves (S = 1,962.9 vs. F = 941.0 mg IgG/dL). During the study, BW was influenced by both CR (P = 0.001) and MR (P < 0.001), where S and Mod calves consistently exhibited greater BW when compared with F and Low calves, respectively. At d 84, Mod calves (F-Mod and S-Mod) were on average 18 kg heavier than Low calves. Similarly, Mod calves exhibited greater fresh tissue weights in the liver, pancreas, spleen, and both the small and large intestines (P < 0.05). Starter intake was influenced by MR (P < 0.001), with Low calves having the greatest intake before and during weaning. However, post-weaning starter intake was greater (P = 0.010) in Mod calves. Fecal consistency was influenced by CR (P = 0.001) and MR (P < 0.001), with S and Low calves having improved fecal consistency. Although no interactions were observed between CR and MR, these findings underscore the importance of considering both colostrum and MR levels in calf nutrition management to optimize growth and improve animal welfare during the early stages of life.
354 Zinc supplementation prior to transit and transit duration effects on feedlot performance and muscle fatigue of beef steers: Part II – Feeding Behavior
Authors: Ortner Brock M , Baumhover Allison M , Schwartzkopf-Genswein Karen S , Thomson Daniel U , Hansen Stephanie L
Published: September 2024

This study assessed the effects of supplemental Zn on cattle feeding behavior after varying transit duration. Angus crossbred steers (80; 265 ± 18 kg) were used in a 2 × 2 factorial design. Steers were assigned to a dietary Zn treatment (DIET) and transit duration (DUR; d 0): Zn0 (no supplemental Zn) or Zn100 (100 mg Zn/kg DM; supplemented as ZnSO4, starting d -42 relative to transit) and short duration (8H; 8 h transit; 707 km) or long duration (18H; 18 h transit; 1608 km). Steers were fed ad libitum via GrowSafe bunks (GrowSafe Systems Ltd., Airdrie, AB, Canada), and steer was experimental unit (n = 1 bunk/pen; n = 5 steers/pen). On d 0, steers were stratified to trailer compartments across diets. The 8H and 18H groups departed at 1000 and 1300 h and returned at 1800 and 0700 h to pre-transit pens, respectively. Following transit, all steers received Zn100. Utilizing GrowSafe Behavior module, a feed event was characterized as a reading with < 300 s interruption with head down (FE-HD; recorded in seconds) and count (number of HD events). Intake rate (g/s) was feed consumed per FE-HD divided by FE-HD duration. Data for the 6-d post transit were analyzed as a complete randomized design utilizing PROC MIXED of SAS 9.4 (SAS Inst. Inc., Cary, NC) with fixed effects DIET, DUR, and DAY as repeated. Pre-transit values served as a covariate. During the week prior to transit, there was a DUR effect for FE-HD average and intake rate (P ≤ 0.03) where 8H had longer FE-HD but reduced intake rate than 18H. There was also a tendency for Zn100 to consume more feed per FE pre-transit (P = 0.07). Post-transit, both average intake and FE-HD average increased with days post-transit (DAY; P ≤ 0.01). Additionally, a DIET × DUR effect was observed for FE-HD count (P = 0.01) where 100 was greater than 0 within 18H and 0 was greater than 100 in 8H. A tendency for a TRT × DAY effect was noted for FE-HD count (P = 0.07) driven by Zn0 decreasing from d 3 to 4. A DUR × DAY effect (P = 0.02) was also noted for FE-HD count where 18H was greater on d 2, 4, and 5. A DUR × DAY effect was observed for FE-HD average (P = 0.01) driven by a d 3 difference where 8H was greater than 18H. Conversely, a DUR × DAY effect was observed for intake rate (P = 0.01) where 18H was greater on d 2, 3, and 6. These data indicate both transit duration and dietary Zn concentration influenced animal behavior post-transit.