Combining Optimization and Simulation for Next-Generation Off-Road Vehicle E/E Architectural Design.

The automotive industry, with particular reference to the off-road sector, is facing several challenges, including the integration of Advanced Driver Assistance Systems (ADASs), the introduction of autonomous driving capabilities, and system-specific requirements that are different from the traditional car market. Current vehicular electrical-electronic (E/E) architectures are unable to support the amount of data for new vehicle functionalities, requiring the transition to zonal architectures, new communication standards, and the adoption of Drive-by-Wire technologies. In this work, we propose an automated methodology for next-generation off-road vehicle E/E architectural design. Starting from the regulatory requirements, we use a MILP-based optimizer to find candidate solutions, a discrete event simulator to validate their feasibility, and an ascent-based gradient method to reformulate the constraints for the optimizer in order to converge to the final architectural solution. We evaluate the results in terms of latency, jitter, and network load, as well as provide a Pareto analysis that includes power consumption, cost, and system weight.

Impact of replacing protein pellets with soybean grain on nutrient utilization and the rumen and blood parameters of feedlot cattle under tropical conditions.

The aim of this study was to explore the effect of replacing protein pellets with soybean grain in high-concentrate diets with or without the addition of silage, on the intake, digestibility, and rumen and blood parameters of feedlot cattle in tropical regions. Four cannulated, crossbred steers were used, 4.5 ± 0.5 years old, with an average weight of 685.55 ± 111.78 kg. The steers were distributed in a 4 × 4 Latin square, in a 2 × 2 factorial scheme (two sources of protein: protein pellets or whole soybean grain, with or without added dietary bulk). There was no effect (P ≥ 0.109) from the interaction between the source of protein and the addition of silage to the diet on dry matter (DM) and nutrient intake, or the digestibility (P ≥ 0.625) of DM or crude protein (CP). However, both factors affected (P ≤ 0.052) the intake of DM, neutral detergent fiber (NDF), and non-fiber carbohydrates (NFC), as well as the independent digestibility (P ≤ 0.099) of fat, NFC, total carbohydrates (TC), and total cholesterol concentration. There was an effect (P ≤ 0.053) from the interaction between the source of protein and the addition of silage to the diet on the digestibility of NDF and total digestible nutrients (TDN), as well as on the glycose concentration (P = 0.003). Blood parameters (i.e. protein, albumin, creatinine, triglycerides, aspartate aminotransferase (AST), and alanine aminotransferase (ALT)) were not affected (P ≥ 0.139) by the source of protein, the addition of silage, or their interaction. Lastly, including 150 g/kg silage DM in a high-grain diet, and using soybean grain as a source of protein in substitution of protein pellet could be a suitable nutritional strategy to ensure adequate DM and nutrient intake and digestibility, with no detrimental effects on rumen and blood parameters of feedlot cattle in the tropics.

A minimally invasive hybrid procedure to correct pectus arcuatum.

BACKGROUND: Pectus arcuatum, also known as horns of steer anomaly or Currarino-Silverman Syndrome, is a distinct chest wall anomaly characterized by severe manubriosternal angulation, a shortened sternum, and mild pectus excavatum. The anomaly is typically repaired using open techniques, employing orthopedic fixation devices. Here, we report the results of a minimally invasive hybrid procedure to repair pectus arcuatum. METHODS: The procedure combines a standard Nuss procedure to correct the depressed sternum with a short upper chest (in boys) or inter-mammary (in girls) incision for bilateral subperichondrial resection of the upper costal cartilages, osteotomy, and correction of the manubrial angulation. The medical records of all patients who underwent the procedure over the last 10 years were reviewed. RESULTS: Five patients, 3 boys and 2 girls, aged 14 to 17 years, underwent the procedure. Three patients had their pectus bars removed 3-4 years after repair. Follow-up after correction ranged from 6 months to 7 years. Good correction resulted in all patients achieving recovery without complications and recurrence. To date, all patients have been satisfied with their results. CONCLUSIONS: The minimally invasive hybrid procedure adequately corrects pectus arcuatum with minimal scarring and high satisfaction.

Myokines Produced by Cultured Bovine Satellite Cells Harvested from 3- and 11-Month-Old Angus Steers.

The myokines interleukin 6 (IL-6), interleukin 15 (IL-15), myonectin (CTRP15), fibronectin type III domain containing protein 5/irisin (FNDC5), and brain-derived neurotrophic factor (BDNF) are associated with skeletal muscle cell proliferation, differentiation, and muscle hypertrophy in biomedical model species. This study evaluated whether these myokines are produced by cultured bovine satellite cells (BSCs) harvested from 3- and 11-month-old commercial black Angus steers and if the expression and secretion of these targets change across 0, 12, 24, and 48 h in vitro. IL-6, IL-15, FNDC5, and BDNF expression were greater (p ≤ 0.05) in the differentiated vs. undifferentiated BSCs at 0, 12, 24, and 48 h. CTRP15 expression was greater (p ≤ 0.03) in the undifferentiated vs. differentiated BSCs at 24 and 48 h. IL-6 and CTRP15 protein from culture media were greater (p ≤ 0.04) in undifferentiated vs. differentiated BSCs at 0, 12, 24, and 48 h. BDNF protein was greater in the media of differentiated vs. undifferentiated BSCs at 0, 12, 24, and 48 h. IL-6, 1L-15, FNDC5, and BDNF are expressed in association with BSC differentiation, and CTRP15 appears to be expressed in association with BSC proliferation. This study also confirms IL-6, IL-15, CTRP15, and BDNF proteins present in media collected from primary cultures of BSCs.

Alterations of rumen and fecal microbiome in growing beef and dairy steers fed rumen-protected Capsicum oleoresin.

The microbiome has been linked to animal health and productivity, and thus, modulating animal microbiomes is becoming of increasing interest. Antimicrobial growth promoters (AGP) were once a common technology used to modulate the microbiome, but regulation and consumer pressure have decreased AGP use in food animals. One alternative to antimicrobial growth promoters are phytotherapeutics, compounds derived from plants. Capsaicin is a compound from the Capsicum genus, which includes chili peppers. Capsaicin has antimicrobial properties and could be used to manipulate the gastrointestinal microbiome of cattle. Both the rumen and fecal microbiomes are essential to cattle health and production, and modulation of either microbiome can affect both cattle health and productivity. We hypothesized that the addition of rumen-protected capsaicin to the diet of cattle would alter the composition of the fecal microbiome, but not the rumen microbiome. To determine the impact of rumen-protected capsaicin in cattle, four Holstein and four Angus steers were fed rumen-protected Capsicum oleoresin at 0 (Control), 5, 10, or 15 mg kg-1 diet dry matter. Cattle were fed in treatment groups in a 4 × 4 Latin Square design with a 21-d adaptation phase and a 7-d sample collection phase. Rumen samples were collected on day 22 at 0-, 2-, 6-, 12-, and 18-h post-feeding, and fecal swabs were collected on the last day of sample collection, day 28, within 1 h of feeding. Sequencing data of the 16s rRNA gene was analyzed using the dada2 pipeline and taxa were assigned using the SILVA database. No differences were observed in alpha diversity among fecal or rumen samples for either breed (P > 0.08) and no difference between groups was detected for either breed in rumen samples or for Angus steers in fecal samples (P > 0.42). There was a difference in beta diversity between treatments in fecal samples of Holstein steers (P < 0.01), however, a pairwise comparison of the treatment groups suggests no difference between treatments after adjusting for multiple comparisons. Therefore, we were unable to observe substantial overall variation in the rumen or fecal microbiomes of steers due to increasing concentrations of rumen-protected capsaicin. We do, however, see a trend toward increased concentrations of capsaicin influencing the fecal microbiome structure of Holstein steers despite this lack of significance.

The microbiome is the collection of microbes present in an animal's body and has been discovered to be directly connected to animal health and productivity. In production animals, such as feedlot cattle, the microbiome can be modulated by antimicrobials to promote growth, but increasing consumer pressure to reduce antimicrobial use has producers seeking alternatives. Capsaicin is a phytotherapeutic derived from chili peppers that can be used to modulate the microbiome due to its antimicrobial properties. Eight steers were fed rumen-protected Capsicum oleoresin to determine its effect on average daily gain. In addition, rumen and fecal samples were collected for microbiome testing. No differences were detected in the rumen microbiomes between cattle fed capsaicin (treatment) or those that received no capsaicin (control). While no overall effect was observed on the fecal microbiome of cattle fed different doses of capsaicin or control, we did observe changes in fecal beta diversity due to capsaicin treatment in Holstein steers fed greater doses. The fecal microbiome structure of Holsteins fed greater dosages of capsaicin differed from those fed control or low doses, as observed by the presence of two distinct clusters. This observation suggests an impact of greater doses of capsaicin treatment on microbiome structure.

Developing models to predict feces and urine excretion in Japanese Black fattening steer by multiple regression analysis.

The objective of this study was to develop models for predicting the amount of feces and urine excreted by Japanese Black fattening steer using a dataset of 119 digestion trials for a total of 46 animals. Correlation analysis was used to analyze the relationships between feces and urine excretion and feed intake, feed digestibility, and nitrogen balance. Multiple regression analysis was conducted to develop models for predicting the amount of feces and urine excreted using the explanatory variables selected from various animal and dietary parameters based on P-value (<0.10) and variance inflation factor (<3.0). Resultingly, dry matter intake was a primary predictor of feces excreted. The prediction equation for the amount of feces excretion as a function of body weight, dry matter intake, and calculated total digestible nutrients fits the data well (adjusted coefficient of determination [adj R2 ] = 0.519, root mean square error = 1.57). Furthermore, the nitrogen content in the urine was the primary predictor of the urine excretion amount. Thus, the prediction equation for the amount of urine excreted using the nitrogen content in urine yielded a highly accurate model (adj R2 = 0.813, root mean square error = 4.12).

Consider the Source: The Impact of Social Mixing on Drylot Housed Steer Behavior and Productivity.

Cattle are a social species in which social mixing can induce physical and psychosocial stress; however, the impact of social mixing on cattle welfare is unknown. Two different sources of genetically similar Angus crossbred steers were transported to the same feedlot and assigned to a pen where they were either socially mixed or housed with individuals from their source herds. Social mixing did not impact average daily gains in pens, feed intake, or feed efficiency; pens of socially mixed steers were more active. Sources differed in their responses to social mixing. One source was unaffected, whereas social mixing negatively impacted productivity for the other source. Irrespective of social mixing, the sources differed in the amount of time per day they spent ruminating and drinking. Group analyses indicated that socially mixing two sources of feedlot steers did not negatively impact group productivity, yet the impacts that were observed at the individual level suggest that prior experiences may influence their ability to cope with social stress, emphasizing the importance of early-life experiences to long-term welfare and productivity. Social mixing was not universally detrimental to cattle welfare, and the source of cattle may have the greatest affect on their performance regardless of whether a social mixing event has occurred.

Effects of the Use of Rice Grain on Growth Performances, Blood Metabolites, Rumen Fermentation, and Rumen Microbial Community in Fattening Hanwoo Steers.

This study aimed to assess the influence of rice grain in the total mixed ration (TMR) on the growth performance, blood metabolites, rumen fermentation, and rumen microbial community of fattening Hanwoo steers. Two experimental diets were prepared: (i) a TMR containing 33% dry matter (DM) corn grains (Corn TMR) and (ii) a TMR containing 33% DM rice grains (Rice TMR). Twenty-two Hanwoo steers (body weight [BW], 498 ± 32 kg; months, 17 ± 0.5) were distributed into two treatment groups in a completely randomized block design according to BW. The Rice TMR group had a higher final BW and DM intake (DMI) compared to those in the Corn TMR group (p < 0.01). However, no difference was observed in the average daily gain (ADG) and feed conversion ratio (FCR) between the two treatments. For the rumen fermentation parameters, the molar portion of butyrate in the Rice TMR was higher than in the Corn TMR (p < 0.01). Streptococcus bovis tended to be higher in the Rice TMR (p = 0.09). The results of this study suggest that using rice grain as the primary starch source in TMRs may be an alternative option for fattening Hanwoo steers.

Evaluation of a ruminally protected blend of pantothenic acid, pyridoxine, folic acid, biotin, and vitamin B12 on finishing steer growth performance, efficiency of dietary net energy utilization, carcass trait responses, and liver abscess prevalence and severity.

The objective of this study was to determine the influence that a ruminally-protected B-vitamin (RPBV) blend (containing vitamin B5, B6, B7, B9, and B12) had on growth performance, efficiency of dietary net energy utilization, carcass trait responses, and liver abscess severity and prevalence in beef steers fed a finishing diet. Steers (n = 246; initial shrunk body weight [BW] = 411 ±â€…25.8 kg) from two different sources, were used in a 126-d RCBD experiment. Within 48 h after arrival, steers were individually weighed and allotted to 1 of 24 pens (n = 8 to 12 steers; 8 pens per treatment) and randomly assigned to 1 of 3 treatments: (1) No RPBV; (2) RPBV1 at 1 g/steer d-1; 3) RPBV2 at 2 g/steer d-1. During the first 14 d, cattle received two transition diets with increasing concentrate. From days 15 to 126, cattle were fed the final diet containing 53% dry-rolled corn; 23% corn silage; 20% MDGS; and 4% suspended supplement. On the first 28 d, steers of RPBV1 had a greater average daily gain (ADG) and better feed conversion (G:F), both by 9% (quadratic effect, P ≤ 0.02). However, cumulatively, no differences (P ≥ 0.13) among treatments were found for dry-matter intake (DMI), live final BW, ADG, or G:F. Carcass-adjusted final BW, ADG, and G:F were not influenced by treatment (P ≥ 0.59). Additionally, carcass weight, dressing percentage, marbling score, kidney-pelvic-heart fat, or BW at 28% empty body fat did not differ among treatments (P ≥ 0.11). Ribeye area (REA) was altered (quadratic effect, P = 0.02) by treatment; steers from RPBV1 had decreased REA compared to others. Additionally, calculated yield grade (YG) and calculated retail yield (RY) were altered (quadratic effect, P ≤ 0.01) by treatment; steers from RPBV1 had increased YG and decreased RY compared to others. Estimated empty body fatness tended (P = 0.06) to be greater from steers-fed RPBV compared to control. Overall USDA YG distribution was altered by dietary treatment (P = 0.01). The proportions of YG1 and YG5 carcasses were unaffected by treatment, but there was a shift in the proportion of carcasses that graded YG2, YG3, and YG4 among treatments. Distribution of USDA Quality Grade was not altered by treatment (P = 0.53). No treatment differences in liver abscess incidence or severity were observed (P = 0.13). The use of RPBV altered carcass muscularity and rib fat accumulation affecting the overall YG distribution. However, RPBV did not appreciably influence any cumulative growth performance measures or liver abscess outcome.

Behavior and heart rate variability after intranasal administration of oxytocin in Holstein steers.

Oxytocin (OXT) is a neuropeptide that regulates memory, emotion, stress response, and behavior in the brain. In our previous study with cattle, we demonstrated the anti-stress effect of intracerebroventricularly administered OXT on the central nervous system. However, it is important to investigate the effects of this peptide after intranasal administration, as it offers convenience and non-invasiveness for practical use. Therefore, this study investigated the effects of intranasal OXT on the behavior and autonomic nervous system of Holstein steers. The experiment followed a within-subjects design, including a total of six steers. Each steer received intranasal administration of either 1 mL of saline (SAL), 100 µg OXT (OXT100), or 200 µg OXT (OXT200). However, due to some issues, the sample size for the OXT200 group was reduced to five. After these treatments, we conducted electrocardiography recordings to analyze heart rate variability (HRV) and also made behavioral observations for 90 min. OXT200 tended to increase the time spent ruminating while lying down (Steel's multiple comparison test; P=0.053). In contrast, OXT treatment did not affect HRV indices. In conclusion, the current OXT dosage did not significantly affects behavior or the autonomic nervous system. However, the observed tendency to increase rumination may suggest a central effect of OXT.

Effects of dietary glycerol supplementation on meat quality, palatability, and lipid metabolism gene expression in the longissimus thoracis of Hanwoo steers.

This study tested the hypothesis that dietary glycerol supplementation (GS) would affect growth of Hanwoo steers, beef marbling and palatability, and gene expression for lipid uptake and transport and lipogenesis in the longissimus thoracis (LT). Diets with or without 45.2 g daily glycerol supplementation/kg dry matter concentrate were tested in fourteen Hanwoo steers during a 16-week feeding trial. GS did not affect (P ≥ 0.40) the average daily gain or the gain-to-feed ratio. GS increased the LT marbling score (P = 0.01). GS enhanced (P ≤ 0.01) the sensory traits, including the flavor and overall acceptance of the LT. GS tended (0.05 < P ≤ 0.10) to upregulate mRNA levels of fatty acid translocase, lipoprotein lipase, and fatty acid binding protein 4 genes in the LT. These tendencies of upregulated expression of fatty acid uptake and cytosolic transport genes may, in part, contribute to the increased marbling by GS. The increased marbling degree caused by GS may improve palatability including the flavor and overall acceptance of the LT.

Effects of energy levels on growth performance, carcass characteristics, and fatty acid composition of Holstein steers at different slaughter ages.

We investigated the effect of energy levels on growth performance, carcass characteristics, and fatty acid composition of Holstein steers at different slaughter ages. Forty Holstein steers with an average body weight (BW) of 234.21 ± 7.42 kg and 7.78 ± 0.22 months were randomly allocated to two experimental groups; a 22-month-old experimental group and a 24-month-old experimental group. Total digestible nutrients (TDN) for each group were set to 70% (T1) and 72% (T2) during fattening phase and 74% (T3) and 76% (T4) for the finishing phase, respectively. No difference was observed in the final BW between the experimental groups during the fattening phase. However, in the finishing phase, the final BW of T4 (820.31 kg) group was significantly higher than that of T1 (745.57 kg; p < 0.05). The average daily gain (ADG) of T2 group in the finishing phase and overall period were 1.27 kg and 1.26 kg, respectively, which were significantly higher than those of T1 (1.11 kg and 1.12 kg; p < 0.05). The feed conversion ratio (FCR) and TDN conversion ratio of T2 group in the finishing phase also decreased by 10.23% and 7.73%, respectively, compared to those of T1. The cold carcass weight of T4 group was significantly higher (p < 0.05) than that of T1, whereas back fat thickness, longissimus area, and marbling score were not significantly different among groups. No differences were observed in physicochemical characteristics of the carcass including moisture, crude protein, and crude fat content among groups. However, the composition of fatty acids differed significantly between the groups. The content of C18:0 was significantly lower (p < 0.05) in T4 than in T1 group, and the content of C18:2 was higher in T4 than in T1 and T3 (p < 0.05). Therefore, feeding Holstein steers at a high-energy feeding level during the fattening and finishing phases improves ADG and reduces the slaughter age from 24 months to 22 months.

Metabolomic and transcriptomic study to understand changes in metabolic and immune responses in steers under heat stress.

Heat stress (HS) damages livestock by adversely affecting physiological and immunological functions. However, fundamental understanding of the metabolic and immunological mechanisms in animals under HS remains elusive, particularly in steers. To understand the changes on metabolic and immune responses in steers under HS condition, we performed RNA-sequencing and proton nuclear magnetic resonance spectroscopy-based metabolomics on HS-free (THI value: 64.92 ± 0.56) and HS-exposed (THI value: 79.13 ± 0.56) Jersey steer (n = 8, body weight: 559.67 ± 32.72 kg). This study clarifies the metabolic changes in 3 biofluids (rumen fluid, serum, and urine) and the immune responses observed in the peripheral blood mononuclear cells of HS-exposed steers. This integrated approach allowed the discovery of HS-sensitive metabolic and immunological pathways. The metabolomic analysis indicated that HS-exposed steers showed potential HS biomarkers such as isocitrate, formate, creatine, and riboflavin (P < 0.05). Among them, there were several integrative metabolic pathways between rumen fluid and serum. Furthermore, HS altered mRNA expression and immune-related signaling pathways. A meta-analysis revealed that HS decreased riboflavin metabolism and the expression of glyoxylate and dicarboxylate metabolism-related genes. Moreover, metabolic pathways, such as the hypoxia-inducible factor-1 signaling pathway, were downregulated in immune cells by HS (P < 0.05). These findings, along with the datasets of pathways and phenotypic differences as potential biomarkers in steers, can support more in-depth research to elucidate the inter-related metabolic and immunological pathways. This would help suggest new strategies to ameliorate the effects of HS, including disease susceptibility and metabolic disorders, in Jersey steers.

Effects of feeding wood kraft pulp silage containing sweet-potato shochu distillery by-product on feed intake, feed digestibility, rumen fermentation, blood components, and growth performance in Japanese Black fattening steers during early period.

The effects of long-term feeding of wood kraft pulp (KP) silage containing sweet-potato shochu distillery by-product (SDP) on feed intake, feed digestibility, rumen fermentation, and growth performance of Japanese Black steers were investigated during the early fattening period. Ten Japanese Black steers (9.8 ± 0.6 months of age) were used in this study. Five steers (KP group) were fed KP silage as a replacement for 10% timothy hay (dry matter bases), in contrast to the other five (control group). KP silage consisted of 92.9% KP and 7.1% SDP (dry matter bases). The experiment was conducted for 18 weeks. No significant differences were observed in terms of feed intake, feed digestibility, or daily body weight gain between the groups. In addition, diurnal changes in the rumen pH and ruminal lipopolysaccharide activity did not differ between the groups. However, the plasma concentration of aspartate transaminase in the KP group was slightly lower (P = 0.078) than that in the control group. Thus, our study suggested that feeding KP silage does not reduce feed intake or affect the rumen fermentation or growth performance of Japanese Black fattening steer.

Messenger RNA Gene Expression Screening of VIP and PACAP Neuropeptides and Their Endogenous Receptors in Ruminants.

Vasoactive Intestinal Peptide (VIP) and Pituitary Adenylate-Cyclase-Activating Peptide (PACAP) are anti-inflammatory neuropeptides that play important roles in human and rodent gut microbiota homeostasis and host immunity. Pharmacologically regulating these neuropeptides is expected to have significant health and feed efficiency benefits for agriculturally relevant animals. However, their expression profile in ruminant tissues is not well characterized. To this end, we screened for VIP and PACAP neuropeptides and their endogenous GPCRs using 15 different tissues from wethers and steers by RT-qPCR. Our results revealed relatively similar expression profiles for both VIP and PACAP neuropeptide ligands in the brain and intestinal tissue of both species. In contrast, the tissue expression profiles for VPAC1, VPAC2, and PAC1 were more widespread and disparate, with VPAC1 being the most diversely expressed receptor with mRNA detection in the brain and throughout the gastrointestinal tract. These data are an important first step to allow for future investigations regarding the VIP and PACAP signaling pathways in livestock ruminant species.

Evaluation of pineapple stem starch as a substitute for corn grain or ground cassava in a cattle feedlot for 206 or 344 days: feedlot performance, carcass characteristics, meat quality, and economic evaluation.

The pineapple stem starch substituted for ground cassava or corn as a carbohydrate source in the concentrate diet. The experiment used 36 Holstein crossbred steers (aged 22 months) with an average initial body weight of 453.0 ± 35.3 kg. The experimental units were randomly assigned to three different starch sources of concentrate diets: ground corn (GC), ground cassava (CA), or pineapple stem starch (PS) with two different feeding periods: (1) period 1 for 206 days or (2) period 2 for 344 days with six replicates per treatment (two steers per replication), arranged in a completely randomized design. The animals were slaughtered at the end of the experimental periods. After that, the feedlot performance, carcass characteristics, meat quality, and economic return were evaluated. The results showed that the steers fed PS had a greater weight gain, average daily gain, and lower feed: gain ratio when fed for 206 days than when fed for 344 days, but dry matter intake, carcass characteristics, meat quality, and fatty acids profile did not differ between treatments in both periods of feeding except C14:1 and C18:0. The steers fed PS showed the greatest economic return. As a substitute for cassava or corn, pineapple stem starch had no negative impact on the feedlot performance, carcass characteristics, and meat quality. These results indicate that pineapple stem starch could be a useful feedstuff for the feedlot steers diets as an alternative starch source.

Identification of candidate proteins regulated by long-term caloric restriction and feed efficiency in longissimus dorsi muscle in Korean native steer.

We aimed to investigate candidate proteins related to long-term caloric restriction and feed efficiency in bovine longissimus dorsi muscle (LM). A total of 31 Korean native steers were randomly distributed to ad libitum (n = 16) or caloric restriction group (n = 15) to conduct two feeding trials for 13 mon. In the first trial (10-18 mon of age), steers were fed with 100% ad libitum (NEg = 0.63 Mcal/kg) or caloric restriction (80% of the previous day's feed intake of ad libitum group). In the second trial (18-23 mon of age), the energy value of 100% ad libitum diet was 1.13 Mcal/kg NEg and those in caloric restriction group diet was 0.72 Mcal/kg NEg. At the endpoint of this experiment, in each group, 6 animals were selected with high (n = 3) or low feed efficiency (n = 3) to collect muscle tissue samples (6 animals/group). From muscle tissues of 23 mo of age, we excavated 9 and 12 differentially expressed (two-fold or more) proteins in a nutritional group and feed efficiency group using two-dimensional electrophoresis, respectively. Of these proteins, heat shock protein beta-6 was up-regulated in both the caloric restriction and the low feed efficiency group. In bovine embryonic fibroblasts, the mRNA expression of heat shock protein beta-6 increased after adipogenic differentiation, however, decreased after myogenic differentiation. Our data provide that heat shock protein beta-6 may be an adipogenic protein involved in the mechanism of caloric restriction and feed efficiency in the LM of the steer.

2-Hydroxy-4-(Methylthio) Butanoic Acid Isopropyl Ester Supplementation Altered Ruminal and Cecal Bacterial Composition and Improved Growth Performance of Finishing Beef Cattle.

The objective of this study was to evaluate the effects of isopropyl ester of 2-hydroxy-4-(methylthio)-butyrate acid (HMBi) on ruminal and cecal fermentation, microbial composition, nutrient digestibility, plasma biochemical parameters, and growth performance in finishing beef cattle. The experiment was conducted for 120 days by a complete randomized block design. Sixty 24-month-old Angus steers (723.9 ± 11.6 kg) were randomly assigned to one of the flowing three treatments: basal diet (the concentrate: 7.6 kg/head·d-1, the rice straw: ad libitum) supplemented with 0 g/d MetaSmart® (H0), a basal diet supplemented with 15 g/d of MetaSmart® (H15), and a basal diet supplemented with 30 g/d of MetaSmart® (H30). Results showed that the average daily gain (ADG) increased linearly (P = 0.004) and the feed conversion ratio (FCR) decreased linearly (P < 0.01) with the increasing HMBi supplementation. Blood urea nitrogen (BUN) concentration significantly decreased in the H30 group (P < 0.05) compared with H0 or H15. The ruminal pH value tended to increase linearly (P = 0.086) on day 56 with the increased HMBi supplementation. The concentrations of ammonia-nitrogen (NH3-N), propionate, isobutyrate, butyrate, isovalerate, valerate, and total volatile fatty acid (VFA) were linearly decreased in the cecum (P < 0.05). The results of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) showed that the abundance of most pathways with a significant difference was higher in the rumen and lower in the cecum in the H30 group compared to the H0 group, and those pathways were mainly related to the metabolism of amino acids, carbohydrates, and lipids. Correlation analysis showed that ADG was positively associated with the ratio of firmicutes/bacteroidetes both in the rumen and cecum. Additionally, the abundance of Lachnospiraceae, Saccharofermentans, Lachnospiraceae_XPB1014_group, and Ruminococcus_1 was positively correlated with ADG and negatively correlated with FCR and BUN in the rumen. In the cecum, ADG was positively correlated with the abundances of Peptostreptococcaceae, Romboutsia, Ruminococcaceae_UCG-013, and Paeniclostridium, and negatively correlated with the abundances of Bacteroidaceae and Bacteroides. Overall, these results indicated that dietary supplementation of HMBi can improve the growth performance and the feed efficiency of finishing beef cattle by potentially changing bacterial community and fermentation patterns of rumen and cecum.

Animal Welfare and Food Safety When Slaughtering Cattle Using the Gunshot Method.

Transporting cattle from farm to slaughterhouse is often stressful for the animal, which can impair the meat quality. With the gunshot method, the animal is stunned with a rifle shot while together with familiar herd members in their home environment, exsanguinated and transported to a nearby slaughterhouse. Aiming to assess the consequences for animal welfare and food safety, 20 Hereford steers aged 18-54 months were shot with .22 Magnum ammunition from an elevated position and distance of 6-12 m. Each time, only one out of four to seven animals in a 16 × 10 m corral was shot. Dressing was done on farm. Based on the animals' behaviour and blood concentrations of cortisol, glucose and lactate, stress levels before shooting were low. Eleven animals were deeply stunned, the consciousness of seven others was ambiguous, and two were poorly stunned. Two animals were reshot. The bleed-out was satisfactory for all animals, and little or no faecal contamination was found on the carcasses. We conclude that the gunshot method is applicable to large beef steers while maintaining a satisfactory level of animal welfare and food safety, provided that the necessary conditions can be attained.

Timing of maternal supplementation of dried distillers grains during late gestation influences postnatal growth, immunocompetence, and carcass characteristics of Bos indicus-influenced beef calves.

This 2-yr study investigated the timing of dried distillers grains (DDG) supplementation during the third trimester of gestation of Bos indicus-influenced beef cows and its impact on their offspring performance. On day 0 of each year (84 d before calving), Brangus cows (n = 84/yr; cow age = 8 ± 3 yr) were stratified by initial body weight (BW; 482 ± 75 kg) and body condition score (BCS; 5.3 ± 0.8) and assigned randomly to one of six bahiagrass (Paspalum notatum) pastures (experimental units; 14 cows/pasture). Treatments were assigned randomly to pasture (2 pastures/treatment/yr) and consisted of no prepartum supplementation (CON), 2 kg/d of DDG from day 0 to 42 (LATE42), or 1 kg/d of DDG from day 0 to 84 (LATE84). Following calving (day 84), cow-calf pairs remained in their respective pastures, and cows were offered sugarcane molasses + urea (1.82 kg of dry matter/cow/d) from day 85 until the end of the breeding season (day 224). On day 347, steer calves (n = 38/yr; 11 to 15 steers/treatment/yr) were weaned and transported to the feedlot (1,193 km). Steers were penned according to cow prepartum pasture and managed similarly until the time of harvest. BCS at calving was greater (P < 0.01) for LATE42 and LATE84 vs. CON cows but did not differ (P = 0.16) between LATE42 and LATE84 cows. Calving date, calving percentage, and birth BW of the first offspring did not differ (P ≥ 0.22) among treatments. However, LATE42 cows calved their second offspring 8 d earlier (P = 0.04) compared with CON and LATE84 cows. At weaning (first offspring), LATE84 calves were the heaviest (P ≤ 0.05), CON calves were the lightest, and LATE42 calves had intermediate BW (P ≤ 0.05). Steer plasma concentrations of cortisol and haptoglobin and serum bovine viral diarrhea virus type-1 titers did not differ (P ≥ 0.21) between treatments. Steer serum parainfluenza-3 titers were greater (P = 0.03) for LATE42 vs. CON steers, tended to be greater (P = 0.10) for LATE84 compared with CON steers, and did not differ (P = 0.38) between LATE42 and LATE84 steers. Steer feedlot BW, average daily gain, dry matter intake, and hot carcass weight did not differ (P ≥ 0.36) between treatments. Marbling and the percentage of steers grading choice were greater (P ≤ 0.04) for LATE42 vs. CON steers, whereas LATE84 steers were intermediate. In summary, different timing of DDG supplementation during the third trimester of gestation could be explored to optimize cow BCS and offspring preweaning growth and carcass quality.

This 2-yr study evaluated the effect of the timing of dried distillers grains (DDG) supplementation during the last trimester of gestation in Bos indicus-influenced beef cows and the subsequent impact on their offspring. Brangus cows were allocated to one of the three prepartum treatments consisting of no prepartum supplementation, 2 kg/d of DDG for the first half of the last trimester of gestation, or 1 kg/d of DDG for the entire length of the last trimester of gestation. Prepartum supplementation, regardless of supplementation length, improved cow body condition scores at the time of calving. Calf birth weights were not affected by prepartum maternal treatment. Calves born to cows that received prepartum supplementation had greater weaning weight compared with no prepartum supplementation. However, weaning weights were improved to the greatest extent when calves were born to cows that received supplementation for the entire length of late gestation. Steer antibody response to parainfluenza-3 was improved with prepartum maternal supplementation, regardless of supplementation length. Furthermore, concentrating the total amount of supplement offered to the first half of the last trimester of gestation improved marbling and increased the percentage of steers grading choice compared with no prepartum supplementation or supplementation during the entire last trimester.