Search Results (139)

Yajiangxue cattle (XF) is three-way crossbred cattle developed specifically for producing high-quality beef in the Tibetan Plateau by introducing the bloods of Tibetan yellow cattle (HF) and Angus cattle into Tibetan yak (MF). In the present study, we mainly focused on fat deposition and metabolism changes and used RNA-seq and LC-MS/MS-based metabolomics to partially explain the meat quality improvement in Yajiangxue cattle. Differential expression analysis revealed 1762, 2949, and 2931 different expression genes in XF vs. HF, XF vs. MF, and XF vs. cattle–yak (PF), respectively, such as BMP2, WISP2, FGF1, IL1B, IL6, and WNT5B. Immune response, oxidation–reduction processes, and fatty acid metabolism were markedly enriched. Furthermore, an initial identification revealed 319 metabolites using positive ion mode and 289 metabolites using negative ion mode in bovine adipose tissue across four breeds/populations. Of these, 143 were differential metabolites in positive ion mode, while 166 were in negative ion mode. The main pathways of metabolism affected by breed/population were unsaturated fatty acid biosynthesis, tryptophan and tyrosine biosynthesis, primary bile acid biosynthesis, cholesterol metabolism, beta-alanine metabolism, etc. Similarly, both the transcriptome and the metabolome results highlighted fatty acid metabolism. These results could help elucidate the biological mechanisms involved in fat deposition and identify valuable biomarkers for specific metabolite accumulation. Full article

Lumpy skin disease (LSD) is a contagious animal disease caused by the lumpy skin disease virus (LSDV). LSD can be transmitted through direct, indirect and insect vectors, severely impacting global cattle production. To evaluate difference in immune response and gut microbiota of 30 healthy 16–18 months old Angus cattle, treated with live attenuated or inactivated goatpox vaccine virus strains. The cattle were randomly divided into three groups (10 animals per group): Group A—goatpox live attenuated vaccine; Group B—goatpox inactivated vaccine; Group C—control (saline). Blood samples were collected on days 14, 28, 42, and 56 post-vaccination to assess hematological parameters, serum biochemical indices, and antibody levels; rectal feces were collected on day 28 for 16S rRNA analysis of gut microbiota. Results showed that, on day 28, both Group A and Group B reached their peak antibody levels (the log₁₀ value of Group A was 2.6, and that of Group B was 2.7), with about 90% of the cattle in each vaccinated group testing antibody-positive. On day 42, Group B retained 90% seropositivity, whereas Group A declined to 80%. Significantly altered in vaccinated Groups (A and B) compared to controls on days 14 and 28 (p < 0.05). Hematological parameters (PLT, NEUT, and LYM) and serum biochemical indices (AST, TP, and GGT) were elevated early after vaccination but returned to baseline by days 42 and 56.Which returned to control levels by days 42 and 56. On day 28 post-vaccination, Vaccinated cattle showed significantly higher gut microbiome richness and diversity than unvaccinated controls (p < 0.05). At the phylum level, the dominance was observed in Firmicutes and Bacteroidetes: the relative abundances were 62.90% and 29.65% in Group A, 60.84% and 30.13% in Group B, and 49.99% and 39.73% in Group C, respectively. These findings indicate that the inactivated goatpox vaccine elicits a more durable and stable antibody response, maintaining higher specific antibody titers, and induces more pronounced shifts in the gut microbiota community structure at the phylum level compared with the live attenuated vaccine. Full article

A 2-year-old Aberdeen Angus cow was presented with lethargy and decreased appetite at the VA-MD College of Veterinary Medicine Large Animal Teaching Hospital. Initial clinical examination revealed cyanosis, tachycardia, polycythemia, and a significant increase in lactate levels. The heifer experienced spontaneous death while hospitalized, prompting a postmortem examination. Gross evaluation demonstrated that the aorta arose entirely from the right ventricle, while the main pulmonary artery maintained its normal position, consistent with a diagnosis of double-outlet right ventricle. Additional cardiac abnormalities were identified, including an atrial septal defect, ventricular septal defect and marked right ventricular hypertrophy. These defects fall under the category of double-outlet right ventricle malformation. While congenital heart defects are a more recognized cause of cardiac failure and mortality in calves, they should remain a consideration in cases of sudden death, even in adult cattle. Full article

Limited molecular data exist on zoonotic parasites Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in Angus calves from Guizhou, China. This study constitutes the first molecular epidemiological survey of these pathogens in this region. 817 fecal samples from Angus calves across 7 intensive beef farms (Bijie City). Nested PCR methods targeting SSU rRNA (Cryptosporidium spp.), gp60 (Cryptosporidium bovis subtyping), bg/gdh/tpi (G. duodenalis), and ITS (E. bieneusi) coupled with DNA sequencing were employed. DNA sequences were analyzed against the NCBI. database. Statistical differences were assessed via a generalized linear mixed-effects model. Cryptosporidium spp. prevalence 23.5% (192/817; 95% CI 28.1–34.6%), with C. bovis predominating 89.6% (172/192; 95% CI 84.4–93.5%) and six subtypes (XXVIa-XXVIf). Highest infection in 4–8-week-olds 29.9% (143/479; 95% CI 25.8–34.1%) (p < 0.01). G. duodenalis: 31.3% (256/817; 95% CI 28.1–34.6%) positive, overwhelmingly assemblage E 97.6% (6/256; 95% CI 0.9–5.0%), zoonotic assemblage A was marginal 0.7% (6/817; 95% CI 0.3–1.6%). Farm-level variation exceeded 10-fold (e.g., Gantang: 55.0% (55/100; 95% CI 44.7–65.0%) vs. Tieshi: 4.9% (5/102; 95% CI 1.6–11.1%). E. bieneusi: prevalence 19.7% (161/817; 95% CI 17.0–22.6%), exclusively zoonotic genotypes BEB4: 49.7% (80/161; 95% CI 41.7–57.7%); I: 40.4% (65/161; 95% CI 32.7–48.4%). Strong diarrhea association (p < 0.01) and site-specific patterns (e.g., Guanyindong: 39.2%). While Giardia exhibited the highest prevalence (31.3%) with minimal zoonotic risk, Enterocytozoon—despite lower prevalence (19.7%)—posed the greatest public health threat due to exclusive circulation of human-pathogenic genotypes (BEB4/I) and significant diarrhea association, highlighting divergent control priorities for these enteric parasites in Guizhou calves. Management/Public health impact: Dominant zoonotic E. bieneusi genotypes (BEB4/I) necessitate: 1. Targeted treatment of 4–8-week-old Angus calves. 2. Manure biofermentation (≥55 °C, 3 days), and 3. UV-disinfection (≥1 mJ/cm²) for karst water to disrupt transmission in this high-humidity region. Full article

In beef cattle production, both diet and breed are key factors influencing the composition and quality of meat. This study evaluated the effects of rumen-protected cod liver oil supplementation on meat and fat quality parameters in Limousin (n = 30) and Red Angus (n = 30) bulls maintained under identical conditions. During the final three weeks of finishing, animals received 100/g/day of cod liver oil. Red Angus bulls exhibited a significantly higher intramuscular fat content in meat compared to Limousin (p < 0.01). The study demonstrated a reduction (p < 0.05) in intramuscular fat content in both breeds receiving cod liver oil supplementation. In Limousin, cis-oleic acid (C18:1 cis-9) levels increased significantly in meat (p < 0.05) without a concurrent increase in trans isomers. Subcutaneous fat in both breeds showed a significant increase in monounsaturated fatty acids in the supplemented group compared to the control (p < 0.01). Limousin bulls also showed reduced levels of myristic acid (C14:0) and stearic acid (C18:0) in subcutaneous fat. Additionally, Limousin muscle tissue showed significantly higher (p < 0.01) concentrations of C18:3n3, C22:6n3, and total polyunsaturated fatty acids (PUFAs) compared to Red Angus. These finding indicate that the short-term dietary inclusion of rumen-protected cod liver oil in cattle rations enhances the nutritional profile of beef, potentially offering benefits for human health. Full article

With the growing global population, the demand for beef is increasing, making the genetic improvement of beef cattle crucial for sustainable production. This study aimed to estimate genetic parameters using different models and predict body weight in Angus cattle to enhance the accuracy of genetic evaluation and support optimal breeding and selection programs. We used the inclusion or exclusion of maternal genetic effects, maternal permanent environmental effects, and the presence or absence of covariance between maternal and direct genetic effects to distinguish between the six animal models. The variance components and genetic parameters of 13,607 weight records from Angus cattle were estimated using the Average Information Restricted Maximum Likelihood (AI-REML) method. The best estimated model was selected based on the Akaike Information Criterion (AIC) and Likelihood Ratio Test (LRT). The results of this study revealed that, in addition to individual genetic effects, maternal genetic effects had a significant impact on unbiased and accurate genetic parameter estimates of body weight in Angus cattle. The total heritability estimated with the best model for body weight at birth (BW0), 3 months (BW3), 6 months (BW6), 12 months (BW12), and 18 months (BW18) was 0.215 ± 0.007, 0.340 ± 0.021, 0.239 ± 0.035, 0.362 ± 0.044, and 0.225 ± 0.048, respectively. The maternal heritability ranges from 0.017~0.438 and significantly affects Angus cattle throughout their growth and development stages, with the effect decreasing with increasing age. Positive correlations were observed between body weights at different months of age, ranging from 0.061 to 0.828. BW6 has a high positive genetic correlation with later age weight, and BW6 is a good predictor of later age weight. Thus, it is possible to optimize breeding programs and accelerate genetic progress by selecting for higher 6-month-old live weights for early Angus selection. In addition, our results emphasize the importance of considering maternal effects in genetic evaluation to improve the efficiency and accuracy of selection programs and thereby contribute to sustainable genetic improvement in beef cattle. Full article

Bovine viral diarrhea virus (BVDV) remains a major cause of calf diarrhea with substantial economic impacts on global cattle production. While emerging evidence suggests that the host microbiota may modulate viral infection processes, the specific gut microbial alterations induced by BVDV infection require elucidation. This study investigated gut microbiota composition and functional changes in BVDV-infected cows through 16S rRNA sequencing. Following the epidemiological screening of a large Angus cattle herd using RT-PCR, we identified four persistently infected (PI) animals and four BVDV-negative controls. Fecal analysis revealed Firmicutes and Bacteroidetes as dominant phyla in both groups. A significant increase in the Ruminococcus genus was observed in PI cows (p < 0.05), with LEfSe analysis identifying Paludibacter as a BVDV-associated biomarker. The PI group exhibited reduced alpha diversity (Faith’s PD index, p < 0.05) and elevated histidine metabolism pathway abundance compared to controls (p < 0.05). These findings demonstrate that persistent BVDV infection induces structural and functional modifications in the bovine gut microbiota, particularly through the enrichment of specific bacterial taxa and altered metabolic potential. The results provide new insights into virus–microbiota interactions, establishing a foundation for understanding how BVDV infection may influence host physiology through microbial community changes. Full article

Castration is an essential procedure in beef cattle management, designed to enhance meat quality, regulate aggressiveness, and control undesirable breeding. This study compared the impacts of Burdizzo and surgical castration on the immunological, oxidative, and inflammatory responses in Angus calves. Calves were randomly assigned to the Burdizzo (n = 4) and surgical (n = 4) castration groups. Blood samples were collected before castration and 3, 6, 24, and 48 h post-castration for the measurement of the pro-inflammatory cytokines TNF-α and IFN-γ, the anti-inflammatory cytokine IL-10, the oxidative stress markers malondialdehyde and nitric oxide, the total antioxidant capacity, and peripheral blood mononuclear cell populations, including CD3⁺CD4⁺, CD3⁺CD8⁺, and CD3⁺WC1⁺ T-cells. The results showed that Burdizzo castration caused significantly higher levels of IFN-γ at 3 and 6 h, TNF-α at 24 and 48 h, IL-10 at 3 and 24 h, and malondialdehyde at 24 h post-castration (p < 0.05), indicating more intense inflammatory and oxidative stress responses. Both methods caused alterations in CD3⁺CD4⁺ and CD3⁺CD8⁺ T-cell counts, while Burdizzo castration induced longer-lasting immune activation. These findings indicate that surgical castration may provide welfare advantages by mitigating prolonged inflammation and stress and promoting faster recovery. This study offers insights into optimal castration practices prioritizing productivity and animal welfare. Full article

A previous study demonstrated that a 19-nucleotide edit, encoding a six amino acid substitution in the bovine CD46 gene, dramatically reduced bovine viral diarrhea virus (BVDV) susceptibility in a cloned Gir (Bos indicus) heifer. The present study aimed to replicate this result in American Angus (Bos taurus) using genetically matched controls and larger sample sizes. CRISPR/Cas9-mediated homology-directed repair introduced the identical CD46 edit, encoding the A₈₂LPTFS amino acid sequence, into exon 2 of CD46 in primary Angus fibroblasts. Thirty-three cloned embryos (22 CD46-edited and 11 unedited) were transferred to recipient cows. However, all pregnancies resulted in pre- and perinatal losses due to cloning-related abnormalities, preventing in vivo BVDV challenge. Consequently, ex vivo BVDV susceptibility assays were performed on primary fibroblast cell lines rescued from deceased cloned Angus calves. Infection studies revealed significantly reduced susceptibility in the edited lines, comparable to the resistance previously observed from the edited Gir heifer. These studies extend the applicability of this finding from Gir to the most common US beef breed, Angus, suggesting the potential for broad application of CD46 editing in BVDV control. Continued advancements in cloning technology will enhance the potential of gene-editing for producing disease-resistant livestock. Full article

This trial aimed to investigate the effects of compound essential oils (EO) on the fattening performance, blood physiological–biochemical indices, and intestinal microbiota in late-fattening Simmental crossbred bulls. Twenty healthy Simmental crossbred bulls (Simmental × Charolais × Angus) with similar initial body weights of 442 (±72.49) kg were randomly divided into two groups: a control group (basal diet, CON group) and a compound essential oil group (basal diet + 16 g/head/day, EO group). The trial included a 14-day pre-feeding period and a 42-day experimental period, totaling 56 days. The results showed the following: (1) The EO group exhibited a significantly higher average daily gain (ADG), immunoglobulin A (IgA), immunoglobulin G (IgG), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-PX), glucose (GLU), dopamine (DA), basophil count (Baso), mean corpuscular hemoglobin (MCH), and platelet distribution width (PDW) compared to the CON group (p < 0.05), while the mean corpuscular volume (MCV) was significantly lower (p < 0.05). (2) Although the compound essential oil supplementation did not alter the relative abundance of major intestinal microbial taxa, it significantly improved the intestinal microbiota structure (p < 0.05), increased fiberdegrading microbiota, and promoted short-chain fatty acid production. (3) The relative abundance of the intestinal microbiota norank_f__UCG-010 showed significant positive correlations with ADG, GSH-PX, IgG, DA, T-SOD, GLU, IgA, and Baso (p < 0.05), while Christensenellaceae_R-7_group abundance was positively correlated with ADG, IgA, and Baso (p < 0.05). In conclusion, the compound essential oil enhances healthy and efficient fattening in beef cattle by improving the intestinal microbial structure, increasing beneficial bacteria, regulating the nutrient metabolism through key bacterial genera, and enhancing the immune function, antioxidant capacity, and energy metabolism levels. Full article

Tall fescue toxicosis negatively impacts blood flow, elevates body temperature, and reduces beef cattle’s average daily gain (ADG). In previous studies, isoflavones have diminished the symptoms of tall fescue toxicosis in ruminants. Therefore, this dataset determined the impact of low concentrations of isoflavone doses on animal vasculature, body temperature, ADG, and rumen microbial communities in beef cattle. A 21-day experiment with Angus cattle consisted of four isoflavone doses: 0 g, 2 g, 4 g, and 6 g, along with a control group. Isoflavones were mixed with 0.5 kg of dried distiller’s grains (DDGs). Daily individual rectal temperatures were recorded. Weekly blood serum was collected via coccygeal venipuncture, blood vasculature data were measured via color Doppler ultrasound, and body weight (BW) was recorded. Approximately 100 mL of rumen content was collected at the end of the trial. The pulsatility index (PI) decreased in the control group compared to the 2 g and 4 g groups (p = 0.01). Animals in the isoflavone treatment groups recorded a higher rectal temperature (p < 0.05). ADG was reduced in animals undergoing isoflavone treatments (p < 0.001). Finally, there was no impact on the rumen microbial communities (p > 0.05). Isoflavone supplementation may mitigate tall fescue toxicosis and improve animal performance at greater doses. Full article

Intramuscular fat (IMF) content in beef cattle is a critical determinant of beef meat quality, as it positively influences juiciness, tenderness, and palatability. In China, the crossbreeding of Wagyu and Angus is a prevalent method for achieving a better marbling level. However, the molecular mechanisms governing IMF regulation in these crossbreeds remain poorly understood. To elucidate the mechanism of IMF deposition in these crossbred cattle, we conducted a comparative transcriptomic analysis of longissimus dorsi muscles and livers from cattle with divergent IMF content. RNA-seq revealed 940 and 429 differentially expressed genes (DEGs) in the liver and muscle, respectively, with 60 genes co-differentially expressed (co-DEGs) in both tissues. Functional enrichment highlighted lipid metabolism pathways including fatty acid β-oxidation, PPAR signaling, and glycerolipid metabolism. A total of eleven genes including ACAA2, ACADL, ACOX2, CPT1B, CPT2, LPL, SLC27A1, ACAT1, GK, ACOX3, and ACSM5, were screened as key candidate genes for IMF deposition. A “liver–muscle” regulatory network of IMF deposition was built to illustrate the tissues’ interaction. The reliability of the transcriptomic data was verified by quantitative reverse real-time PCR (qRT-PCR). Our findings provide novel molecular markers for increasing the IMF content and accelerating the genetic improvement of beef quality traits in crossbred cattle. Full article

Cryptosporidium spp. are protozoan pathogens that are widespread within mammals. In recent years, extensive molecular epidemiology studies on Cryptosporidium in dairy cattle have been conducted in Yunnan and worldwide. However, the infection status of these pathogens in beef cattle in Yunnan remains unclear. To examined the occurrence of Cryptosporidium spp. in beef cattle in Yunnan Province, China, we collected 735 fecal samples from six breeds of beef cattle in five regions of Yunnan. Nested PCR and DNA sequencing revealed the infection, species, and genotypes of Cryptosporidium spp. in these animals. The occurrence of Cryptosporidium spp. in Simmental cattle, Brahman cattle, Aberdeen Angus cattle, Yunnan Yellow cattle, Dulong cattle, and Hereford cattle was 32.9% (137/416), 3.8% (4/106), 24.4% (20/82), 3.8% (3/79), 3.2% (1/31), and 0% (0/21), respectively, with an overall rate of 22.4% (165/735). Regarding the regions, the occurrence of Cryptosporidium spp. in Boshan City, Kunming City, Lincang City, Dehong City and Xishuangbanna City was 41.8%, 28.6%, 19.4%, 6.7%, and 3.8%, respectively. In terms of age, the infection rates of Cryptosporidium spp. in pre-weaned, post-weaned, juvenile, and adult cattle were 62.1%, 52.6%, 42.7%, and 7.7%, respectively. According to sex, male cattle were more susceptible to Cryptosporidium infection (28.0%) than females (15.7%). Four Cryptosporidium species were identified in beef cattle: C. andersoni (n = 146), C. bovis (n = 11), C. ryanae (n = 7), and C. occultus (n = 1). Multilocus sequence typing analysis at the MS1, MS2, MS3, and MS16 gene loci revealed four subtype families of C. andersoni (A4A4A4A1, A5A4A4A1, A4A4A2A1, A1A4A4A1). Additionally, sequencing analysis of the 60-kDa glycoprotein gene identified three subtype families of C. bovis (XXVIc, XXVId, XXVIe) and one subtype family of C. ryanae (XXIb). These findings document the occurrence of Cryptosporidium spp. in beef cattle in Yunnan Province for the first time, providing reference data on the distribution, infection rate, species diversity, and genetic structure of these pathogens in China. To effectively reduce the prevalence of Cryptosporidium spp. in beef cattle in Yunnan, the implementation of proper sanitation management, rigorous rodent control, and farmer education programs is crucial. These integrated measures are critical for maintaining herd health, reducing economic losses, and ensuring meat safety across the province. Full article

The use of non-invasive technologies is among the most accurate methods for assessing meat quality parameters. Beef tenderness and palatability are strongly influenced by the amount of intramuscular fat, commonly referred to as marbling. Marbling is widely used in breeding programs to select animals with superior meat quality. In this study, we analyzed 236 Angus bulls and 22 Angus heifers from various farms in Lithuania, all aged 450 ± 112 days. Ultrasound examinations were performed using a linear transducer with a silicone standoff to evaluate the loin eye area. Key meat quality indicators, such as fat thickness, loin area and thickness, and intramuscular fat, were found to increase with the weight of bulls, ranging from 365 ± 12.70 kg to 825.57 ± 11.75 kg (p < 0.001), and heifers, ranging from 273 ± 20.71 kg to 767 ± 41.01 kg (p < 0.001). The highest intramuscular fat values were observed at 7.50 ± 0.75% (p < 0.05) to 6.9 ± 1.36% (p < 0.1) in bulls weighing 431.33–825.57 kg and 7.98 ± 0.28% (p < 0.001) in heifers weighing 603 kg. These findings demonstrate the feasibility of selecting Angus cattle for improved meat quality traits across different weight categories. Full article

The average daily gain (ADG) is a critical index for evaluating growth rates in cattle and is closely linked to the economic benefits of the cattle industry. Heredity is one of the factors affecting the daily gain of cattle. However, the molecular mechanisms regulating ADG remain incompletely understood. This study aimed to systematically unravel the molecular mechanisms underlying the divergence in ADG between high average daily gain (HADG) and low average daily gain (LADG) Angus cattle through integrated multi-omics analyses (microbiome, metabolome, and transcriptome), hypothesizing that the gut microbiota–host gene–metabolism axis is a key regulatory network driving ADG divergence. Thirty Angus cattle were classified according to their HADG and LADG. Fecal and serum samples were collected for 16S, fecal metabolome, and blood transcriptome analysis. The results showed that compared with the LADG group, the abundance of Firmicutes increased in the HADG group, while the abundance of Bacteroidetes and Proteobacteria decreased. Metabolomics and transcriptomic analysis revealed that KEGG pathways associated with differentially expressed genes (DEGs) and differentially abundant metabolites (DAMs) were enriched in bile acid metabolism. Spearman correlation analysis showed that Oscillospira was positively correlated with ZBTB20 and negatively correlated with RADIL. ZBTB20 was negatively correlated with dgA-11_gut_group. This study analyzed the regulatory mechanism of average daily gain of beef cattle from genetic, metabolic, and microbial levels, providing a theoretical basis for analyzing the mechanism of differential daily gain of beef cattle, and has important significance for improving the production performance of beef cattle. The multi-omics network provides biomarker foundations for machine learning-based ADG prediction models, offering potential applications in precision breeding. While these biomarkers show promise for precision breeding, their causal roles require further validation. The conclusions are derived from a single breed (Angus) and gender (castrated males). Future studies should include females and diverse breeds to assess generalizability. Full article