大豆秸秆菌糠喂牛的效果研究

本试验用大豆秸秆菌糠替代50％,70％和100％粗饲料（干玉米秸）饲喂鲁西牛。结果表明,大豆秸秆菌糠替代粗饲料的比例以50％为宜,日增重比 对照组高131g,提高29．91％,差异极显著（P＜0．05）。     

牛胚胎移植技术的产业化研究

本文探讨了引进国外优质奶、肉牛冷冻胚胎建立核心群，以及供体牛选择、超数排卵、胚胎冷冻保存和分割等相关技术，为牛胚胎移植产业化奠定基础。     

牦牛、犏牛及黄牛肉脂肪酸和风味物质的分析

随机选取青海省果洛州同一放牧群体的1.5岁牦牛（♂）和犏牛（♂）各3头,与青海省湟中县1.5岁的3头黄牛（♂）做比较研究,利用气质联用仪对牦牛、犏牛和黄牛肉中脂肪酸组成及含量进行分析,利用高效液相色谱法对其肉中的肌苷、肌苷酸和硫胺素进行测定,采用高氯酸滴定法测定其肉中谷氨酸钠的含量。结果表明：①牦牛、犏牛和黄牛肉中饱和脂肪酸和单不饱和脂肪酸的含量无显著差异（P〉0.05）;多不饱和脂肪酸在犏牛肉中含量最高,明显高于牦牛和黄牛肉（P〉0.05）。②牦牛肉肌苷的含量明显高于同龄黄牛（P〈0.05）;三种牛肉中肌苷酸的含量无显著差异（P〉0.05）;犏牛肉硫胺素的含量最高,明显高于同龄黄牛（P〈0.05）;犏牛与黄牛肉谷氨酸钠的含量明显高于同龄牦牛（P〉0.05）。     

Evaluation of the Abbott LCx Mycobacterium Tuberculosis Assay for Direct Detection of Mycobacterium Bovis in Bovine Tissue Samples

The commercial LCx amplification assay, usually employed to detect the Myocobacterium tuberculosis complex in respiratory specimens, was evaluated by comparing the results it gave with those obtained using Löwenstein-Jensen solid medium and pathological findings on 55 lymph nodes from cattle with positive and 10 lymph nodes from cattle with negative skin tests for tuberculosis. Fifty-three cultures (51 and 2, respectively) were positive for M. bovis, while the results for the LCx assay and the histological method were positive in 48 (45, 3) and 24 (20, 4) samples, respectively. None of the samples from cattle from certified tuberculosis-free herds were positive by any of the procedures. The results obtained with the LCx assay, compared with the culture procedure, regarded as the gold standard among the diagnostic techniques, gave a specificity of 91.6% and sensitivity of 90.5%. Although the sensitivity of LCx was suboptimal, DNA of M. bovis was detected in 81.8% of the skin test-positive animals. Amplification techniques could provide a rapid and reasonably reliable tool for detecting bovine tuberculosis.     

张掖市发展生态畜牧业的潜力与优势分析

基于生态畜牧业的内涵,结合张掖市肉牛产业发展现状,分析了发展生态畜牧业的潜力与优势,并提出了相应对策及建议。     

临泽县肉牛产业现状的调查与思考

肉牛产业是临泽县的主导产业。近年来,我县立足区位优势和资源优势,以建设全省牛羊产业大县和实施"张掖百万头肉牛基地工程"为契机,着力做大做强奶肉牛产业。通过政策扶持、科技助推、典型带动等措施大力推进标准化生产,实现农民增收。本文对临泽县肉牛发展的有利因素、存在问题进行分析,提出了肉牛发展对策和建议。     

山东省牛场粪污处理现状的调研报告

介绍山东省牛场粪污处理现状,分析养牛业粪污处理中存在的问题,并提出了解决山东省养牛业粪污处理的建议.     

Genome-wide association study for age at puberty in young Nelore bulls

Selection for bulls that would reach puberty early reduces the generation interval and increases fertility and herd productivity. Despite its economic importance, there are few QTL associated with age at puberty described in the literature. In this study, a weighted single-step genome-wide association study was performed to detect genomic regions and putative candidate genes related to age at puberty in young Nelore bulls. Several protein-coding genes related to spermatogenesis functions were identified within the genomic regions that explain more than 0.5% of the additive genetic variance for age at puberty in Nelore bulls, such as ADAM11, BRCA1, CSNK2A, CREBBP, MEIOC, NDRG2, NECTIN3, PARP2, PARP9, PRSS21, RAD51C, RNASE4, SLX4, SPA17, TEX14, TIMP2 and TRIP13 gene. Enrichment analysis by DAVID also revealed several GO terms related to spermatogenesis such as DNA replication (GO:0006260), male meiosis I (GO:0007141), double-strand break repair (GO:0006302), base excision repair (GO:0006284), apoptotic process (GO:0006915), cell–cell adhesion (GO: 0098609) and focal adhesion (GO:0005925). The heritability for age at puberty shows that this trait can be improved based on traditional EBV selection. Adding genomic information to the system helps to elucidate genes and molecular mechanisms controlling the sexual precocity and could help to predict sexual precocity in Nelore bulls with greater accuracy at younger age, which would speed up the breeding programme for this breed.     

德国黄牛改良南阳牛遗传育种研究进展

为了研究德国黄牛改良南阳牛遗传育种研究进展,本文综述了德国黄牛杂交改良南阳牛的历史进程,德国黄牛改良南阳牛杂交后代生产性能研究进展,并提出了德南牛产业化集群开发的合理化建议。     

Vaccination of cows with rough Escherichia coli mutants fails to protect against experimental intramammary bacterial challenge

Vaccination of cows with rough Escherichia coli mutants fails to protect against experimental intramammary bacterial challenge. Vaccine A, a heat-killed Re mutant of strain K12, (UB 1574), was administered as a single parenteral and local dose to 5 cows with 3 control animals and Vaccine B, a heat-killed mutant of O111:B4 (J5) was administered as three parenteral doses into 5 cows with 5 control animals. Following intramammary challenge with a smooth wild-type strain (P4), an acute, severe clinical mastitis developed in all 14 quarters (9 vaccine A and 5 vaccine B) of the vaccinated animals which was indistinguishable from that in the 11 quarters of the control animals. Following vaccine B there was an elevation in serum IgG1 and IgG2 antibody to the common core antigen of endotoxin which, in contrast to the control animals, showed a further increase after intramammary infection.