Performance Of Beef Cattle Research Articles

Effects of fermented Chinese herb residues on growth performance, nutrient apparent digestibility, serum biochemical indices and faecal microbial flora in beef cattle

This study aimed to evaluate the effects of fermented Chinese herb residues on the growth performance, nutrient apparent digestibility, serum biochemical indices and microflora of Simmental beef cattle during the fattening period. Twenty-four healthy Simmental beef cattle with an average body weight of 358.54 ± 65.63 kg were randomly divided into four treatment groups, with 6 replicates. The dietary treatments were as follows: I: basal diet; II, III and IV: 10% corn husk in the diet was replaced by Chinese herb residue, enzyme-fermented residue, and enzyme bacteria co-fermented residue, respectively. The experimental period was 49 days. There was no significant difference in the growth performance of beef cattle (p > 0.05). The ether extract (EE) apparent digestibility of groups III and IV was significantly higher than that of group I (p < 0.05); the apparent digestibility values of nitrogen free extract (NFE) and total phosphorus (P) in group IV were significantly lower than those in the other groups (p < 0.05). The maleic dialdehyde (MDA) contents in groups I and II were significantly higher than those in groups III and IV (p < 0.05). The ACE and Chao1 indices of groups I and III were significantly higher than those of groups II and IV (p < 0.05). The Shannon indices of groups I and III were significantly higher than that of group II (p < 0.05). The abundance of Firmicutes in group III was significantly lower than that in group II (p < 0.05). In conclusion, fermented Chinese herb residues could replace 10% corn husk and be used in beef cattle breeding.

352 Effects of Including a Novel High-Anthocyanin Corn Cob Meal in a High-Roughage Diet on Performance and Gas Flux of Beef Cattle

Abstract Methane (CH4) is a greenhouse gas emitted by cattle that is produced as a byproduct of ruminal fermentation. Dietary inclusion of anthocyanins has previously decreased in vitro CH4 production from both high- and low-roughage diets. Anthocyanins potentially sequester hydrogen in the rumen which may limit CH4 production from methanogenic bacteria. As such, feeding anthocyanins represents a promising CH4 mitigation strategy. Thus, the objective of this preliminary experiment was to determine the effects of replacing conventional [CONV; 0.04 mg anthocyanin×g-1 of dry matter (DM)] corn cob meal (CCM) with a novel high-anthocyanin (Hi-A) CCM [TAMZ101 corn hybrid (4.99 mg anthocyanin×g-1 DM; Texas A&amp;M AgriLife Research; Lubbock, TX)] in a high-roughage (40% DM) diet on growth performance and gas flux of beef cattle. Steers (n =14; average initial body weight = 286 kg ± 17 kg) were trained to individual Calan bunks and randomly assigned to dietary treatments on d 0 using a completely randomized design, where 20% of total diet DM was either Hi-A or CONV CCM. The trial consisted of a 63-d feeding period in which carbon dioxide (CO2) emission, CH4 emission, and oxygen (O2) consumption (g×animal×d-1) were measured using a GreenFeed system (C-Lock Inc.; Rapid City, SD). Statistical analyses were conducted using JMP Pro v.16 (SAS Institute Inc.; Cary, NC) where individual animal served as the experimental unit and treatment was a fixed effect. Cook’s distance values were used to identify and remove outliers for each individual response variable. Statistical significance was set at P ≤ 0.05 with a tendency toward significance defined as 0.05 &amp;lt; P ≤ 0.10. Due to insufficient statistical power, 10.2% and 5.7% numeric increases were statistically undetectable in total dry matter intake (DMI; P = 0.13; 1-ß = 0.31) and average daily gain (ADG; P = 0.19; 1-ß = 0.25) when CONV CCM was replaced with Hi-A CCM. Similarly, marginal numeric differences in feed efficiency, CO2 emission, daily CH4 emission, and O2 consumption were statistically undetectable across treatments (P ≥ 0.18; 1-ß ≤ 0.22). Numeric differences in DMI of steers fed Hi-A CCM contributed to a 7.5% decrease (P = 0.05; 1-ß = 0.51) in CH4 yield (g CH4×kg DMI-1) when compared with steers fed CONV CCM. Treatment did not affect CH4 emission intensity (g CH4×kg ADG-1; P = 0.26; 1-ß = 0.19). Results from this preliminary experiment and a previous in vitro experiment indicate that anthocyanins from Hi-A CCM have CH4 mitigation potential in high-roughage diets. Further research is warranted to determine if anthocyanins are effective at reducing CH4 yield across a range of diet compositions and if anthocyanins from Hi-A CCM can be extracted, condensed, and repackaged into a delivery system that is both economically and logistically feasible.

PSXIV-1 Impact of Slow-Release Nitrogen Or Regular Protein-Based Supplementation During Late Gestation on Maternal and Offspring Performance in Beef Cattle

Abstract The objective of this study was to determine whether supplementing pregnant beef cows with regular nitrogen or a slow-release nitrogen source at the late gestation could enhance the use of a low protein basal diet and improve the performance of cows and their offspring until weaning. Thirty-five pregnant Brahman cows (556 ± 47 kg and 4.5 ± 1.4 years old) were individually housed in covered pens and randomly divided into three groups. From 180 ± 19 days of gestation until calving, cows were fed either a control (CON, n = 12) low crude protein (CP) basal diet (6% of CP, ad libitum) plus mineral mixture (130 g·cow-1·d-1), or the CON treatment supplemented with protein concentrate supplements (40% CP, fed 2 g·kg of BW-1·d-1 in the morning) based either on a regular (REG, n = 11) composition (corn, soybean meal, and urea) or on a slow-release N (SRN, n = 12) source (Timafeed Boost, Roullier Group, Saint-Malo, France) which replaced 60% of soybean meal and urea in the supplement composition. The MN, fetal sex (FS), and MN×FS were used as fixed effects in the statistical model, while the number of previous calvings was considered as a random effect. Maternal initial BW was used as a covariate. Statistical differences were declared at P &amp;lt; 0.05. Supplementation with REG and SRN increased total dry matter intake (DMI) and basal diet intake compared with the control treatment (P &amp;lt; 0.01). Protein supplementation allowed the cows to have a higher average daily gain (P &amp;lt; 0.01; 0.177 and 0.193 kg/day, respectively, for REG and SRN) than the CON treatment (-0.255 kg/day). Body condition score (BCS) also increased (P &amp;lt; 0.01) when cows received protein supplementation in late pregnancy, but with no differences between REG and SRN cows (P = 0.31). Interactions between MN and FS were observed for calf birth weight (CBW, P &amp;lt; 0.01) and calves' average daily gain up to 120 days of age (ADG120, P = 0.01), but not at weaning weight (P = 0.69). Male calves born from REG and SRN cows were born heavier and gained more weight up to 120 days after birth than calves born from CON cows (P &amp;lt; 0.05) but did not differ from each other (P = 0.94 and 0.92, respectively, for CBW and ADG120). Female calves had no differences in CBW and ADG120 as a function of maternal dietary treatment during pregnancy. The REG and SRN calves weaned heavier (P &amp;lt; 0.05) than CON calves. In conclusion, supplementing protein to pregnant beef cows during periods of low CP pasture improves maternal and progeny performance. The SRN-based product can replace the major part of soybean and urea in the protein supplement, achieving same level of improvement in forage utilization and animal performance as the regular protein-based supplement.

349 Effects of Adding a Yeast Blend to Diets with High Levels of Dried Distillers Grains on Feeding Behavior, Intake, and Performance of Beef Cattle Fattened in Feedlot

Abstract Feeding ruminants with a blend of autolyzed yeast grown on sugarcane molasses and live yeast allows nutritionists to explore synergistic effects on digestion and performance (Angulo et al.,2021; Zapata et al., 2021). However, the feeding behavior and the challenges faced in large pen feedlot operations differ from the behavior and challenges faced by animals studied in small groups or metabolic cages. Therefore, we aimed to study the feeding behavior and performance of beef cattle fed in groups in large pens, mimicking the feedlot operations of leading producers and exports of meat in the world. The trial lasted 112 days and was conducted in Nutripura’s research center in the midwest of Brazil. Six hundred five non-castrated males (Nelore and F1 Nelore-Angus), 405 kg (± 35), distributed in 20 pens, were divided into two treatments: 1) Control, a diet with no yeast additives; 2) Yeast Blend (YB), a diet with a blend of autolyzed yeast and live yeast, SymbioYeast, 7g/anima/day (ICC, São Paulo, Brazil). Both diets contained monesin (28 mg/kg DM). The data were analyzed in the software SAS following the model Yijk= μ+Ti + Fj + Bk +еijk (μ = general mean; T = treatment effect; F = Breed effect; B = backgrounding phase effect; e = error). Initial body weight was used as a covariable to analyze final body weight and average daily gain (ADG). Dry matter intake increased (P &amp;lt; 0,05) when animals were supplemented with YB (10,99kg vs. 11,12kg). Final body weight and hot carcass weight tended (0.1 &amp;gt; P ≥ 0.05) to increase when YB was added to the diet. (598 kg vs. 602 kg, 343 kg vs. 345 kg). The ADG was unaffected (P = 0.1069, control 1.735 kg, and YB 1.768 kg). Increasing DMI is a well now property of some yeast derivatives (Torres et al., 2022). This may be related to changes in digestion (Torres et al., 2022) and the diet’s palatability. The palatability of yeast products is claimed on organoleptic and flavor characteristics (Tao et al., 2023). Drone photos taken every 15 minutes suggested that YB altered how animals interact with feed. Feed was delivered between 0700 h and -0930 h and 1300 h and 1530 h. After delivery, a greater percentage of the visit of the animals to the feed bunkers in YB groups. This behavior was even more evident in the morning feed delivery (Figure 1). In summary, YB increased intake and performance. It also changed the interest of animals in visiting feed bunk.

336 Evaluation of a Bacillus Spp. Probiotic on Beef Cattle Performance, Nutrient Digestibility and Enteric Methane Emissions

Abstract Direct-fed microbials have been used in an effort to improve livestock production efficiency and reduce environmental impact. Among other species, spore forming bacteria such as Bacillus spp. present handling and processing advantages to be used as a probiotic. Several studies have demonstrated positive effects of Bacillus spp. on dairy cattle production. However, there is lack of information about its effects on beef cattle. Thus, the objective of this study was to evaluate the effect of a probiotic composed by a mixture of B. subtilis and B. licheniformis on beef cattle performance, nutrient utilization, and enteric methane emissions (CH4). For this purpose, a total of 108 Angus crossbred heifers (318 ± 40.4 kg of BW) were used in a generalized randomized block design. The heifers were fed a sorghum silage-based diet containing 1 of the 2 following treatments: 1) control (CTL, no additive), or 2) Bacillus spp. probiotic (BSL, 310 mg/kg of diet DM), in an attempt to provide an average of 3 g·animal-1·d-1. The experimental period consisted in 7 d of adaptation to the pens, followed by 77 d of performance data collection, 5 d of apparent total tract digestibility measurements, and 5 d of CH4 measurements. No effect of treatment (P &amp;gt; 0.05) was observed for dry matter intake, average daily gain, or gain-to-feed ratio. The inclusion of the probiotic did not affect (P &amp;gt; 0.05) apparent total tract digestibility of dry matter, organic matter, neutral detergent fiber and crude protein, whereas starch digestibility decreased (P = 0.027) with the probiotic inclusion. No differences (P &amp;gt; 0.05) were observed for CH4 between the two treatments. Accordingly, feeding Bacillus spp. did not affect cattle performance, nutrient utilization, or enteric CH4 emissions in beef heifers when included at 310 mg/kg of dietary dry matter.

350 Effects of Adding Yeast Derivatives to High Concentrate Diets on Performance and Feeding Behavior of Beef Cattle Finished in Feedlot

Abstract Yeast derivatives enhance beef cattle performance (Torres et al., 2022), allowing farmers to increase feedlot financial income. However, yeast derivatives vary on yeast species, grown medium, purity, technological processing, yeast cell parts marketed.Thus, in these experiments, we aimed to understand the potential of different yeast derivatives to manipulate performance, feed intake, and feeding behavior. In experiment 1, 1,760 non-castrated males were used to study performance and feed intake. These animals were distributed in large pens, mimicking actual feedlot operations. In xperiment 2, 96 animals with radio frequency identification ear tags were allocated in small groups with induvial access to automatic feeders equipped with scales to study daily individual feeding behavior. Animals were allocated to four treatments: 1) Control, no yeast derivative; 2) AY - 7g/animal/day, autolyzed Saccharomyces cerevisiae grown on sugarcane molasses, RumenYeast (ICC, São Paulo, Brazil); 3) YM - 3g/animal day, yeast rich in soluble yeast metabolites; 4) YB - 5g/animal/day, yeast blend (live Yeast plus autolyzed Yeast. Orthogonal contrasts were performed comparing control against AY, YM, and YB. Differences were declared significant at P &amp;lt; 0.05 and as a trend when 0.05 &amp;lt; P &amp;lt; 0.10. Pen was considered as the experimental unit for experiment 1. For experiment 2, animals were considered the experimental unit. Regarding experiment 1, AY tended to increase adjusted average daily gain and hot carcass weight (Table 1). Dry matter intake did not differ between treatments in experiment 1 (large pen trial). Looking at individual intake data, experiment 2, feeding behavior and water intake changed when yeast derivatives were included in the diet. In general, animals supplemented with AY spent less time eating, which was more evident in the adaptation period (Table 1). AY and YB had stimulated feed intake in some periods of experiment 2. However, the evident less time spent eating by the AY group promoted a greater feeding rate (kg ingested/min) markedly compared with YM and YB, but in general, also greater than control. Considering the initial period of feedlot operations, this greater feeding rate could favor animals supplemented with AY to adapt faster to feedlot diet/feeding conditions. All yeast derivatives increased water intake. In summary, autolyzed Saccharomyces cerevisiae grown on sugarcane molasses increased beef cattle performance and feeding rate. This change in feeding behavior may accelerate the adaptation of beef cattle in the transition from the backgrounding phase to the feedlot operation.

175 Effects of Random Metaphylaxis Administered at Feedlot Arrival to 0, 33, 66, Or 100% of High-Risk Beef Cattle on Health Outcomes, Complete Blood Count, and Growth Performance

Abstract Our objective was to evaluate the effects of random metaphylaxis administered on arrival to 0, 33, 66, or 100% of high-risk beef cattle on clinical health, growth performance, and complete blood cell counts during a 35-d receiving period. Crossbred beef steers (n = 216; arrival BW = 197 ± 6.4 kg) were used in a generalized complete block design consisting of 2 source blocks and 4 treatments. Experimental treatments and steers were randomly assigned to pen within source block: 1) negative control, subcutaneous injection with sterile saline (NCON); 2) 33% of steers/pen given metaphylaxis (33M); 3) 66% of steers/pen given metaphylaxis (66M); and 4) positive control; conventional metaphylaxis given to 100% of steers (CONV). Body weight and blood samples for quantification of complete blood count were collected on d 0, 14, and 35. Pen was considered the experimental unit for all analyses. Continuous data were analyzed using PROC MIXED, and categorical data were analyzed as binomial proportions using PROC GLIMMIX. Treatment was included in the model as a fixed effect and source block was a random effect. Complete blood counts were analyzed as repeated measures, where day was the repeated effect and pen within treatment was the subject. The percentage of steers treated with an antibiotic for bovine respiratory disease (BRD) once was greater (P &amp;lt; 0.01) for NCON and 33M than for 66M and CONV. Neither BW on d 35 nor average daily gain from d 0 to 35 differed among treatments (P &amp;gt; 0.65), but dry matter intake (DMI) and DMI as a percentage of BW from d 0 to 35 was greater (P &amp;lt; 0.03) for 66M and CONV than for NCON and 33M. No differences in hematological variables were detected among treatments (P &amp;gt; 0.19), whereas all complete blood count variables were affected by day (P &amp;lt; 0.01), except for mean corpuscular hemoglobin concentration (P = 0.81). Most notably, the neutrophil:lymphocyte ratio was greater (P &amp;lt; 0.01) on d 0 than on d 14 and 35. These data suggest that arrival metaphylaxis can be administered to 66% of cattle at random without increasing BRD morbidity while simultaneously increasing DMI similar to conventional metaphylaxis. Random metaphylaxis may be a viable method to decrease antibiotic use in the feedlot industry, while maintaining health outcomes and growth performance of high-risk beef cattle.

PSV-20 The Effect of Bacillus Spp. Supplementation on Performance and Immune Function of Heifers Grazing Tall Fescue Pastures

Abstract Probiotics are purported to improve gastrointestinal tract health across a variety of species. Thus, we evaluated the effects of supplementing a blend of Bacillus spp. on performance and immune function in immature beef cattle. Crossbred heifers (n = 192) were stratified by initial body weight (196 ± 15.4 kg) and randomly assigned to 1 of 24 pastures (1.8 ha each) of Kentucky 31 tall fescue. Heifers were offered 2.84 kg daily of a commodity feed blend and the supplement contained either no probiotic (CON) or of Bacillus spp. (BAC). Bacillus spp. was offered at 3 grams per head per day. Heifers were weighed on consecutive days on d 0 and 1, along with d 84 and 85 to establish initial and final body weight. Interim weights were taken every 28 d. A humoral response to chicken egg albumin (OVA) was established following a subcutaneous injection with OVA. To assess heifers’ immune responses, plasma was taken from two heifers per pasture on d 1, 15, 29, 43, and 57. Plasma samples were measured for the presence of anti-OVA IgG, proinflammatory cytokines, anti-inflammatory cytokines, and chemokines. There were no trt*day interactions (P ≥ 0.30) for plasma response variables. Concentrations of pro-inflammatory cytokines IL-1α and IFN-γ decreased (P ≤ 0.01) in heifers supplemented with BAC. The anti-inflammatory cytokine IL-1 F5 decreased (P = 0.02) with BAC supplementation. Chemokines MIG and MIP-1β also decreased (P ≤ 0.03) with BAC supplementation. Heifers fed BAC tended to display (P = 0.09) greater titers of anti-OVA IgG than the control. Body weight and average daily gain did not differ (P ≥ 0.53) throughout the experiment. Under the conditions of this experiment, heifers supplemented with Bacillus spp. demonstrated modulated immune responses.

341 Effect of Multispecies Fungal Culture Extract Supplementation on the Growth Performance and Carcass Characteristics of Feedlot Cattle

Abstract To evaluate the effect of supplementing feedlot cattle with a multispecies fungal culture extract (MFE; Aspergillus flavus, Aspergillus niger, Aspergillus oryzae, Aspergillus terreus, Phlebia radiata, Pyricularia oryzae, Stropharia coronilla, Thanatephorus cucumeris, Trichoderma longibrachiatum, Trichoderma reesei, Trichoderma viride) in growth performance and carcass characteristics, Angus × SimAngus-crossbred steers (n = 14) and heifers [n = 46; body weight (BW) 344 ± 21 kg] were used in randomized complete block design. Cattle were blocked by BW and housed in 4 feedlot pens (randomly assigned 2 pens per treatment) where a hay-based diet was fed for 84 d (backgrounding), followed by a ground corn-based finishing diet. Subsequently, cattle were harvested upon reaching desired 12th rib fat thickness (2.0 cm). Diets were offered ad libitum and with (MFE) or without (CON) the inclusion of the multispecies fungal culture extract supplement. Steers were weighed at 28-d intervals throughout the experimental period and carcass data were provided by a USDA grader. All data were analyzed using the PROC MIXED procedure of SAS considering the fixed effect of treatment and sex, and the random effect of block and pen (block). During the 84-d period of the backgrounding phase, feeding MFE increased (P = 0.05, Table 1) the average daily gain (ADG) by ~10%, and tended to increase (P = 0.06, Table 1) the dry matter intake (DMI). No differences were observed in the gain to feed ratio (G:F) between treatments (P = 0.67, Table 1). At the conclusion of the 84-d period, cattle fed MFE were heavier (P = 0.04, Table 1) than cattle in the CON treatment. In the finishing phase, no treatment differences were observed (P ≥ 0.36) for the ADG, DMI, and G:F. At the end of the experiment, cattle supplemented with MFE were heavier (P = 0.04, Table 1) than cattle in the CON treatment. The quantity of days on feed in the finishing diet required to reach harvesting target was not different (P = 0.60) among treatments. For the carcass characteristics, dietary inclusion of the MFE tended to increase the hot carcass weight (P = 0.10, Table 2) and increased the marbling score (P = 0.01, Table 2). No treatment effect was detected (P ≥ 0.25, Table 2) for the dressing, longissimus muscle area, 12th rib fat thickness, kidney-pelvic-heart fat content, and yield grade. Results from this study suggest that dietary inclusion of a multispecies fungal culture extract might improve the growth performance of beef cattle fed forage-based diets, as well as their carcass characteristics after conclusion of the feedlot finishing phase.

PSIV-7 Optimization of Indigestible Neutral and Acid Detergent Fiber Measurement Protocols

Abstract Dry matter digestibility (DMD) is a factor that impacts nutrient use efficiency and growth performance of beef cattle. Indigestible neutral (INDF) and acid detergent fiber (IADF) are internal markers commonly used to estimate DMD. The objective of this experiment was to optimize existing protocols for determination of INDF and IADF in feedlot rations and feces. This experiment implemented a 2×2×4 factorial arrangement with a starter or finisher diet, with or without a pepsin and HCl pre-digestion of the diets, and with four ruminal incubation lengths (72, 96, 120, or 288 h). The samples used in this experiment were from diets fed and total fecal collections obtained from 6 steers consuming the starter or finisher diet. Fecal and diet marker concentrations were analyzed using a mixed model ANOVA with ruminally canulated steer (n = 2) as a random effect and diet, pre-digestion, marker, time, and possible interactions as fixed effects. A two-sided t-test was used to test if marker fecal recoveries differed from 100%. When diets were pre-digested, a plateau in dietary marker concentration was achieved, where concentrations of both markers were not different (P ≥ 0.10) when incubated for 120 h compared with 288 h. When diets were not predigested, the dietary content of both markers continued to decrease with increasing ruminal incubation length so that marker content of 120-h incubations were significantly greater (P &amp;lt; 0.01) than 288-h incubations, except for IADF content of the finisher diet where the 120 and 288 h were not different (P = 0.77). The dietary content of INDF and IADF for samples that were not pre-digested and incubated for 288 h were not different (P ≥ 0.64) from the samples that were pre-digested and incubated for 120-h. For the INDF marker across both diets, fecal concentrations were lowest (P ≤ 0.01) when ruminally incubated for 288 h compared with all other ruminal incubation durations. The fecal concentrations of IADF were less (P &amp;lt; 0.01) when incubated for 288 h compared with those incubated for 120 h for the starter diet, but only tended (P = 0.07) to be less at those same time points for the finisher diet. When pre-digestion was conducted, only 120-h ruminal incubations had fecal recoveries that were not different (P ≥ 0.26) from 100% for all markers and diet types. If a pre-digestion was not conducted, then only the 288 h length provided fecal recoveries that were not different (P ≥ 0.12) from 100% for all diets and markers. Based on these results, using a pepsin and HCl pre-digestion followed by a 120-h ruminal incubation shortens time requirements and provides acceptable measurements of INDF and IADF concentrations in feeds and feces. If pre-digestion of diet samples is not possible then a 288-h ruminal incubation length is required.

227 Evaluation of Beef Cattle Performance on Nontraditional Beef Cattle Finishing System Compared with Traditional Beef Cattle Finishing System

Abstract While much research exists examining finishing cattle in conventional systems (confined cattle feeding, or feedlot systems), few data exist regarding finishing cattle in non-traditional systems, particularly in the micro-climates of the Gulf Coast. Non-traditional finishing systems feature additional variables and complexities versus feedlot finishing. The objective of this trial was to compare two non-traditional low input finishing cattle programs with a greater input traditional cattle finishing management program. Crossbred beef heifers [n = 12, initial body weight (BW) = 400 kg] were used to evaluate performance and cost of finishing beef cattle on limit-fed supplemental rations (CORN and SBH) compared with a totally mixed, free-choice ration (DIET). Animals were blocked by BW and randomly allotted to three treatments (CORN, n = 4; SBH, n = 4 and DIET n = 4). Two limit fed diets were combinations corn and a protein based mixing pellet (CORN) or soyhulls and a protein based mixing pellet (SBH), both fed at the rate of 1.9% of BW, while providing the heifers with free-choice access to bahiagrass (Paspalum notatum) forage during the summer months; DIET was a more conventional total mixed ration that provided both the concentrate and roughage component and included corn, soyhull pellets, mixing pellet, and cotton gin motes. Cattle were finished for 132 (n = 6) or 174 d (n = 6) and harvested at the MSU Meat Laboratory in Starkville located 235 miles from the trial location. Data were analyzed using MIXED procedure of SAS By design, dry matter intake during the entire finishing phase was greater (P = &amp;lt; 0.0001) for the free-choice DIET (10.8 kg. per day), compared with the limit fed diets (8.5 and 8.4 kg. per day). Overall average daily gain (ADG) was similar (P= 0.10) between both limit-fed diets (0.99 and 0.98 kg. per day for CORN and SBH). Average daily gain of cattle fed DIET (1.14 kg. per day) tended to be greater (P &amp;lt; 0.06) than both CORN and SBH diets. No differences were noted in G:F at any point during the study (P &amp;gt; 0.20). No differences (P &amp;gt; .0.05) were evident for slaughter weight, hot carcass weight, shrink, and dressing percentage among treatments. Total cost of gain for CORN and SOY were $1.74 and $1.65 cents per kilogram compared with DIET of $1.74 cents per kilogram (P = 0.76). Results indicate limit fed CORN and SBH diets could be a viable option to finish beef just as efficiently as a greater roughage total mixed ration (DIET).

Parameter estimation and assessment of bias in genetic evaluation of carcass traits in Hanwoo cattle using real and simulated data.

Most carcass and meat quality traits are moderate to highly heritable, indicating that they can be improved through selection. Genetic evaluation for these types of traits is performed using performance data obtained from commercial and progeny testing evaluation. The performance data from commercial farms are available in large volume, however, some drawbacks have been observed. The drawback of the commercial data is mainly due to sorting of animals based on live weight prior to slaughter, and this could lead to bias in the genetic evaluation of later measured traits such as carcass traits. The current study has two components to address the drawback of the commercial data. The first component of the study aimed to estimate genetic parameters for carcass and meat quality traits in Korean Hanwoo cattle using a large sample size of industry-based carcass performance records (n = 469,002). The second component of the study aimed to describe the impact of sorting animals into different contemporary groups based on an early measured trait and then examine the effect on the genetic evaluation of subsequently measured traits. To demonstrate our objectives, we used real performance data to estimate genetic parameters and simulated data was used to assess the bias in genetic evaluation. The results of our first study showed that commercial data obtained from slaughterhouses is a potential source of carcass performance data and useful for genetic evaluation of carcass traits to improve beef cattle performance. However, we observed some harvesting effect which leads to bias in genetic evaluation of carcass traits. This is mainly due to the selection of animal based on their body weight before arrival to slaughterhouse. Overall, the non-random allocation of animals into a contemporary group leads to a biased estimated breeding value in genetic evaluation, the severity of which increases when the evaluation traits are highly correlated.

PSVI-4 The Influence of Diet Type on Beef Cattle Performance and Meat Quality Characteristics

Abstract The objective of this study was to determine the effect of diet type on feed intake in yearling steers. Hereford steers (n = 21; BW = 444 ± 10 kg) were assigned to one of three drylot pens based on initial BW. Each drylot pen was assigned to one of three diets: a long-stemmed grass hay (HAY, 10.8% CP, 2.11 Mcal ME/kg DM), an alfalfa hay diet (ALF, 20.5% CP, 2.85 Mcal ME/kg DM) or a mixed ration consisting of 30.0% corn silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement (CON, 22.0% CP, 2.90 Mcal ME/kg DM). Animals were fed daily at 0700 and 1700 h and weighed weekly at 0630 h. For the duration of the trial, animals were housed in drylot pens with ad libitum access to feed and water and had shade structures in each pen. Following a 14-day adaptation period, feed intake was recorded for 35 days. Body weight gain for diets HAY, ALF, and CON were 0.1, 0.77, and 1.47 kg/day, respectively. After the intake portion of the study was completed, an animal from each pen was slaughtered and evaluated for meat quality. Hot carcass weights for diets HAY, ALF, and CON were 237.4, 334.7, and 394.8 kg, respectively. Following 14 days aging, samples from the ribeye area were collected from each animal and subjected to sensory analysis and other assessments of quality. Data were analyzed as a completely random design in SAS v9.4. There was not a significant difference between the ALF diet and the CON diet based on assessment from Warner-Bratzler shear force, carcass yield, marbling score, and sensory assessment (P &amp;lt; 0.05). It was concluded that high-quality forage can achieve similar carcass quality without detrimental effects on meat quality when compared with a high concentrate diet.

259 Evaluation of Methane and Carbon Dioxide Production from Cattle on Different Diet Adaptation Strategies

Abstract An experiment was conducted to evaluate impacts of RAMP (Cargill Corn Milling, Blair, NE) on methane (CH4) and carbon dioxide (CO2) emissions, performance, and carcass characteristics of beef cattle during the grain adaptation phase and finishing phase. Crossbred steers [n = 64; initial body weight (BW) = 347 ±7 kg] were utilized in two treatments; RAMP, fed 100% RAMP during step one and then stepped up to a common finisher diet consisting of 65.5% steam-flaked corn (SFC), 22.5% Sweet Bran (SB), 8% wheat straw, and 4% supplement. The second treatment was control (CON) fed 30.5% SFC, 22.5% SB, 8% wheat straw 35% alfalfa hay, and 4% supplement during step one and then stepped up to the common finisher diet. There were 8 steers per pen and 4 paired replications. Replications were stepped up together and rotated through a two-chamber emissions barn in 5-day cycles to measure CH4 and CO2 emissions at three time points: step one of step-up phase, early feeding phase (one week after starting the finishing diet), and later finishing phase (13 weeks after starting the finishing diet). Performance data were analyzed using the MIXED procedure of SAS with treatment and BW block as fixed effects and emissions data analyzed with BW block and treatment as fixed effects and barn chamber as a covariate. Feeding RAMP during step one of the step-up phase led to a decrease in CH4, as g/d (P = 0.03) and a decrease in the CH4:CO2 ratio (P = 0.02). However, CH4 as g/kg of dry matter intake (DMI) was not affected by treatment (P = 0.25). Control steers had a decrease in CO2 as g/day (P = 0.03), but not as CO2 g/kg of DMI (P = 0.31). There were no differences in DMI (P = 1.00) during the step-up phase, averaging 10.3 kg/d for both treatments. For measures taken while all cattle were on the common finishing diet, RAMP did not reduce CH4, as g/d or g/kg DMI (P ≥ 0.27), CO2 as g/d or g/kg DMI (P ≥ 0.37), or CH4:CO2 (P = 0.12). There were no significant differences in DMI (P = 0.49) whole cattle were in the emissions barn during the feeding phase. There were no significant differences for interim (d 66) cattle performance including BW (mean 504 kg; P = 0.84), DMI (mean 9.7 kg; P = 0.27), ADG (mean 2.33 kg/d; P = 0.88), or G: F (mean 0.246; P = 0.30). Feeding RAMP to cattle during the grain adaptation phase resulted in a 12% decrease in methane emissions on a g per day basis without affecting cattle performance. This reduction in emissions didn’t carry over into the finishing phase when a common diet was fed.

Effects of Diets Combining Peanut Vine and Whole-Plant Corn Silage on Growth Performance, Meat Quality and Rumen Microbiota of Simmental Crossbred Cattle.

Peanut vine is a typical peanut by-product and can be used as a quality roughage resource. Whole-plant corn silage is a commonly used roughage. However, few studies have investigated the effects of diets combining peanut vine and whole-plant corn silage on growth performance, antioxidant capacity, meat quality, rumen fermentation and microbiota of beef cattle. To investigate these effects, eighty Simmental crossbred cattle (body weight, 451.27 ± 10.38 kg) approximately 14 months old were randomly divided into four treatments for a 90-day feeding experiment. A one-way design method was used in this experiment. According to the roughage composition, the cattle were divided into a control treatment of 45% wheat straw and 55% whole-plant corn silage (WG), and three treatments of 25% peanut vine and 75% whole-plant corn silage (LPG), 45% peanut vine and 55% whole-plant corn silage (MPG), and 65% peanut vine and 35% whole-plant corn silage (HPG), and the concentrate was the same for all four treatment diets. The results showed that compared to the WG group, the MPG group experienced an increase in their average daily feed intake of 14%, an average daily gain of 32%, and an increase in SOD activity in the spleen of 33%; in the meat, dry matter content increased by 11%, crude protein by 9%, and ether extract content by 40%; in the rumen, the NH3-N content was reduced by 36%, the relative abundance of Firmicutes increased, and the relative abundance of Bacteroidetes decreased (p < 0.05). These results showed the composition of 45% peanut vine and 55% whole-plant corn silage in the roughage improved growth performance, antioxidant capacity, meat quality, rumen fermentation, and microbiota of beef cattle.

Dietary Supplementation of Tannic Acid Promotes Performance of Beef Cattle via Alleviating Liver Lipid Peroxidation and Improving Glucose Metabolism and Rumen Fermentation.

This study aimed to investigate the effects of dietary tannic acid (TAN) on the gas production, growth performance, antioxidant capacity, rumen microflora, and fermentation function of beef cattle through in vitro and in vivo experiments. TAN was evaluated at 0.15% (dry matter basis, DM) in the in vitro experiment and 0.20% (DM basis) in the animal feeding experiment. The in vitro results revealed that compared with control (CON, basal diet without TAN), the addition of TAN significantly increased the cumulative gas production and asymptotic gas production per 0.20 g dry matter substrate (p < 0.01), with a tendency to reduce methane concentration after 96 h of fermentation (p = 0.10). Furthermore, TAN supplementation significantly suppressed the relative abundance of Methanosphaera and Methanobacteriaceae in the fermentation fluid (LDA > 2.50, p < 0.05). The in vivo experiment showed that compared with CON, the dietary TAN significantly improved average daily gain (+0.15 kg/d), dressing percent (+1.30%), net meat percentage (+1.60%), and serum glucose concentration (+23.35%) of beef cattle (p < 0.05), while it also significantly reduced hepatic malondialdehyde contents by 25.69% (p = 0.02). Moreover, the TAN group showed significantly higher alpha diversity (p < 0.05) and increased relative abundance of Ruminococcus and Saccharomonas (LDA > 2.50, p < 0.05), while the relative abundance of Prevotellaceae in rumen microbial community was significantly decreased (p < 0.05) as compared to that of the CON group. In conclusion, the dietary supplementation of TAN could improve the growth and slaughter performance and health status of beef cattle, and these favorable effects might be attributed to its ability to alleviate liver lipid peroxidation, enhance glucose metabolism, and promote a balanced rumen microbiota for optimal fermentation.

Determination of climatologically suitable places in Türkiye for feedlot cattle production using the Comprehensive Climate Index model.

The purpose of this study was to determine climatologically suitable places to raise feedlot cattle in Türkiye. The Comprehensive Climate Index (CCI), a model that enables one to quantify beef cattle performance based on environmental conditions (temperature, relative humidity, wind speed, solar radiation) at any time in the year, was used to predict dry matter intake (DMI), average daily gain (ADG), and feed efficiency (FE) of feedlot cattle. Thirty years of daily average temperature, relative humidity, and wind speed values were obtained for 15 cities, namely, Antalya, Balikesir, Çorum, Diyarbakir, Edirne, Elazig, Erzincan, Erzurum, Eskisehir, Isparta, Izmir, Kayseri, Konya, Sivas, and Van. Measured daily solar radiation values were not available and values were calculated based on a formula that takes hemisphere, latitude, and day of the year into account. Since mostly dairy breed calves are placed into a feedlot in Türkiye, the Holstein option in the CCI model was chosen to calculate the maintenance energy requirement. Based on previous feedlot feeding studies conducted in Türkiye, it was assumed that calves would be placed on feed at 250 kg and be marketed at 520 kg, that the diet would have 2600 kcal/kg metabolic energy, and that DMI would be 2.31% of the body weight. Results indicate that cattle raised in Antalya (the hottest place) and Erzurum (the coldest place) had the lowest and highest DMI, respectively (P<0.05). Summer months depressed the DMI of cattle in hotter cities and winter months increased the DMI of cattle in colder cities (P<0.05). Feedlot cattle raised in hotter and colder regions of Türkiye had lower ADG than other places having a more temperate climate (P<0.05). In general, cattle raised in a hotter climate had better FE than those raised in a cold climate (P<0.05).

Breeding profile and reproductive performance of beef cattle kept by smallholder farmers in Monta District, Bima Regency, Indonesia

This study investigates beef cattle's breeding profile and reproductive performance kept by smallholder farms in Monta District, Bima Regency, West Nusa Tenggara Province. In-depth interviews were conducted with fifty smallholder farmers, and observations were made on ninety-eight cows. Data on farmers' demographics, breeding profiles, management, and reproductive performance were collected and analyzed using descriptive analysis. The average age of the farmers was 44.32±6.61 years, with an average livestock farming experience of 33.14±6.17 years and an average cattle ownership of 5.02±3.96 heads. Most farmers (98.0%) engaged in beef cattle farming as a supplementary business for savings and insurance purposes. Interestingly, none of the smallholder farmers were members of livestock groups or had received any formal beef cattle farming training. The study's findings indicate promising results concerning beef cows' management and reproductive performance. The observed parameters include the average age of the first estrus at 26.03±5.01 months, the first mating age at 26.55±5.02 months, and the first calving age at 36.76±5.02 months. The average calf weaning age was 3.93±1.11 months, and the postpartum mating interval was 4.20±0.90 months. The cows exhibited an average of 1.59±0.49 services per conception, with an average days open period of 4.61±1.10 months. The calving interval was found to be 13.71±1.06 months. Moreover, the cow reproductive index was recorded at 0.88±0.07 head/year, indicating commendable management practices and reproductive performance. In conclusion, this study reveals that productive-age farmers with livestock experience engage in beef cattle farming as a supplementary business for savings. The findings suggest that beef cattle management and performance are commendable, considering the favorable calving interval and cow reproductive index.

Influence of irrigation and supplementation on performance and ingestive behavior of beef cattle on mixed grass pastures

Influence of irrigation and supplementation on performance and ingestive behavior of beef cattle on mixed grass pastures

Heating Drinking Water in Cold Season Improves Growth Performance via Enhancing Antioxidant Capacity and Rumen Fermentation Function of Beef Cattle.

The research aimed to investigate the suitable drinking water temperature in winter and its effect on the growth performance, antioxidant capacity, and rumen fermentation function of beef cattle. A total of 40 beef cattle (640 ± 19.2 kg) were randomly divided into five treatments with eight cattle in each treatment raised in one pen according to initial body weight. Each treatment differed only in the temperature of drinking water, including the room-temperature water and four different heat water groups named RTW, HW_1, HW_2, HW_3, and HW_4. The measured water temperatures were 4.39 ± 2.546 °C, 10.6 ± 1.29 °C, 18.6 ± 1.52 °C, 26.3 ± 1.70 °C, and 32.5 ± 2.62 °C, respectively. The average daily gain (ADG) showed a significant linear increase during d 0 to 60 and a quadratic increase during d 31 to 60 with rising water temperature (p < 0.05), and the highest ADG of 1.1911 kg/d was calculated at a water temperature of 23.98 °C (R2 = 0.898). The average rectal temperature on d 30 (p = 0.01) and neutral detergent fiber digestibility (p < 0.01) increased linearly with increasing water temperature. Additionally, HW_2 reduced serum triiodothyronine, thyroxine, and malondialdehyde (p < 0.05), and increased serum total antioxidant capacity (p < 0.05) compared with RTW. Compared with HW_2, RTW had unfavorable effects on ruminal propionate, total volatile fatty acids, and cellulase concentrations (p < 0.05), and lower relative mRNA expression levels of claudin-4 (p < 0.01), occludin (p = 0.02), and zonula occludens-1 (p = 0.01) in the ruminal epithelium. Furthermore, RTW had a higher abundance of Prevotella (p = 0.04), Succinivibrionaceae_UCG-002 (p = 0.03), and Lachnospiraceae_UCG-004 (p = 0.03), and a lower abundance of Bifidobacteriaceae (p < 0.01) and Marinilabiliaceae (p = 0.05) in rumen compared to HW_2. Taken together, heated drinking water in cold climates could positively impact the growth performance, nutrient digestibility, antioxidant capacity, and rumen fermentation function of beef cattle. The optimal water temperature for maximizing ADG was calculated to be 23.98 °C under our conditions. Ruminal propionate and its producing bacteria including Prevotella, Succinivibrionaceae, and Lachnospiraceae might be important regulators of rumen fermentation of beef cattle drinking RTW under cold conditions.