Objective This study aimsed to explorinvestigate the effects of body brushing on the intestinal flormicrobiota structure, serum metabolic characteristics, and antioxidant capacity ofin Bohai Black cattle, so as to provide a theoretical basis for the application and improvement of welfare tools in Bohai Black cattle breeding. Method Eighteen 12-month-old healthy male Bohai Black cattle with an average body weight of (195 ± 6.73) kg were randomly divided into a control group (C2) and a body brushing group (N2), with 9 cattle per group, and the experimental period lasted 180 days. At the end of the trial, fecal samples were collected for 16S rRNA gene sequencing, and jugular blood samples were harvested to separate serum for untargeted metabolomic sequencing and determination of antioxidant indices. Result Compared with the control group, the Shannon index and Simpson index of intestinal microbiota in the body brushing group were significantly higher (P < 0.05), while the number of observed species and Chao1 index tended to be higher. NMDS analysis revealed significant differences in microbial community structure between the two groups (P < 0.05). Orthogonal partial least squares discriminant analysis (OPLS-DA) showed distinct separation of serum metabolites between the two groups. A total of 180 upregulated and 43 downregulated differential metabolites were identified, mainly including amino acid derivatives and fatty acid derivatives. Key metabolic pathways such as arginine biosynthesis and tricarboxylic acid (TCA) cycle were significantly enriched (P < 0.05). Body brushing significantly increased the activities of superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and catalase (CAT), and decreased malondialdehyde (MDA) content (P > 0.05). Correlation analysis indicated that the core metabolites ornithine and citrulline were specifically associated with the core intestinal genera g_5-7N15 and g_Prevotella. Conclusion In summary, body brushing can improve the abundance and structure of intestinal microbiota in Bohai Black cattle, regulate arginine biosynthesis and the TCA cycle pathway, enhance blood antioxidant enzyme activities, and thereby significantly improve the antioxidant capacity of Bohai Black cattle.

Objective This study aims to analyze the genetic diversity and population genetic structure of the conservation population of Jinnan cattle, evaluate genomic relationships among individuals, and conduct molecular mating, thereby better protecting and utilizing the genetic resources of Jinnan cattle. Method A total of 161 Jinnan cattle (46 bulls and 115 cows) were genotyped using the bovine 20 K single nucleotide polymorphism (SNP) chip. After quality control, the genotypic data were used to analyze genetic diversity, population genetic structure, and calculate genomic relationships. Genetic contributions of bulls were optimized to minimize inbreeding coefficients in the next generation while maintaining population genetic diversity. Result The results showed that after quality control, 17070 SNP loci were retained. The average observed heterozygosity of the individuals was 0.387, the average expected heterozygosity was 0.386, and the mean SNP polymorphism information content was 0.305. A total of 1,907 runs of homozygosity (ROH) were detected, with an average length of 7.754 Mb and an average of 12.973 ROH segments per individual. The average inbreeding coefficient based on ROH was 0.060. According to the family evolutionary tree, this Jinnan cattle population can be clearly divided into more than 8 families. The genetic diversity of this population is 0.888. Based on the relationship matrix constructed by whole-genome SNP loci, the genetic relationship between individuals ranges from -0.107 to 0.521.When SNPs were divided into haplotype blocks to build the relationship matrix, pairwise relationships ranged from 0 to 0.269 with a mean of 0.112. By optimizing bull genetic contributions to minimize next-generation inbreeding, the top 10 bulls accounted for 57.639% of the total genetic contribution. Conclusion In summary, the conservation population of Jinnan cattle has abundant genetic diversity and low inbreeding level. The kinship estimated based on haplotypes can provide a theoretical basis for scientific mating and conservation utilization of Jinnan cattle.

Objective This crossbreeding test was conducted to evaluate the effects of Red Angus crossbreeding on growth and slaughter performance of Dabieshan cattle and characterize the resulting heterosis, aiming to provide theoretical basis and practical support for germplasm optimization and new beef strain breeding. Method In this study, Red Angus cattle were used as male parent and Dabieshan cattle were used as female parent to carry out progressive hybridization test. Thirty Dabieshan cattle (D), hybrid F1 generation (F1) and hybrid F2 generation (F2) were selected to systematically determine their growth performance and slaughter performance indexes, so as to promote the breeding of new strains for meat. Result The results showed that the body weight and body size of F1 were significantly superior to those of purebred D at all monthly ages (P<0.05). Among them, the body weight, body length, body height, chest girth and cannon circumference of male and female F1 calves at the birth stage were 27.5 kg, 69.1 cm, 70.2 cm, 71.3 cm, 12.8 cm and 24.6 kg, 70.0 cm, 67.4 cm, 70.4 cm, 12.3 cm respectively. All indicators were significantly higher than those of male and female D (P<0.05). The 24-month-old body weight of F1 bulls and cows were 526.7 and 448.4 kg, which were significantly increased by 67.5% and 53.3% compared with D, respectively (P<0.05). Those of F2 bulls and cows reached 564.6 and 462.2 kg, representing increases of 79.6% and 58.1% relative to D (P<0.05). The body length, body height, chest girth and cannon circumference of F2 bulls were 134.7, 124.3, 176.2 and 20.3 cm, respectively, all significantly higher than those of D (P<0.05). For F2 cows, the corresponding values were 128.8, 120.7, 169.2 and 18.9 cm, respectively, which were also significantly greater than those of D (P<0.05). In terms of slaughter performance after fattening, the pre-slaughter live weight and net meat percentage of F2 reached 604.3 kg and 41.66%, which were 105.8 kg and 1.34 percentage points greater than those of purebred D, respectively. The net meat weight of F2 was 251.7 kg, which was significantly greater than that of D and F1 (P<0.05). Conclusion In conclusion, Red Angus cattle had a significant crossbreeding improvement effect on Dabieshan cattle, and F2 exhibited the optimal comprehensive performance.

Local cattle breeds represent a national strategic animal genetic resource, endowed with irreplaceable value in terms of their distinctive meat quality and flavor, stress resistance, and environmental adaptability. In recent years, the field of digital and intelligent technologies has advanced by leaps and bounds. A new-generation integrated biotechnological breeding system, characterized by artificial intelligence, gene chips, and smart breeding platforms, is reshaping the landscape of beef cattle germplasm innovation. This article provides a comprehensive review of the research and development advancements in domestic intelligent breeding platforms and high-throughput gene chips specifically designed for beef cattle. It places particular emphasis on comparing the core features, parameter configurations, technical strengths, application scenarios, and strategic implications of three types of domestically developed chips tailored for local cattle breeding. Furthermore, it offers a detailed introduction to the establishment and operational status of several pivotal domestic intelligent breeding platforms dedicated to local beef cattle, including the National Beef Cattle Genetic Evaluation Center and Whole Genome Selection Platform, the Huaxi Cattle Intelligent Breeding Management System, the Inner Mongolia BeefNet Precision Breeding and Breeding System Cloud Platform, as well as the Ningxia Beef Cattle Breeding Information Management and Breeding Analysis System. The application of digital intelligence in empowering germplasm innovation technologies for local cattle breeds has yielded significant results. Meanwhile, it further analyzes the practical applications of machine learning and deep learning in key scenarios amid the rapid development of artificial intelligence, including intelligent phenotypic identification of beef cattle, non-destructive meat quality evaluation, optimization of genomic selection models, and full industry chain traceability. Finally, the paper points out the issues of scarcity of high-quality annotated breeding datasets, weak model interpretability, insufficient promotion and application, and difficulty in popularization among small and medium-sized ranches. It suggests solutions such as establishing unified data standards, algorithm interfaces, and computing power centers, developing small sample and federated learning, promoting open source sharing of core algorithms and models, and proposes the vision of building a unified and open intelligent local cattle breeding cloud ecosystem in the future, thereby providing a reference for the high-quality and sustainable development of China's local cattle breeding industry.