当归提取物对围产期奶牛生产性能及健康状况的影响

试验旨在研究当归提取物对围产期奶牛生产性能及健康状况的影响。选择60头荷斯坦奶牛按胎次、上一泌乳周期产奶量、预产期相近的原则随机分成4组,对照组饲喂粉状精料,试验一组将精料中的部分蛋白饲料制成颗粒,试验二、三组分别在蛋白颗粒饲料中添加0.4%和0.8%的当归提取物。试验测定采食量、奶产量、乳成分、血液指标及胎衣不下、子宫炎等健康指标。结果表明:添加当归提取物能显著提高奶牛采食量及产奶量(产后45 d内)(P<0.05);对乳成分无显著影响(P>0.05),血液生化指标变化较小;对部分产后疾病的预防效果较为明显,产后首次发情日期提前。研究显示,在日粮中以颗粒料为载体添加当归提取物对提高围产期奶牛的生产性能、改善健康状况有显著作用。     

补铜对奶牛血浆铜含量和铜蓝蛋白活性及其相关性的影响

本试验选取了大庆地区某奶牛群11头泌乳奶牛，检测补铜前后奶牛血浆铜含量和铜蓝蛋白(CP)活性的变化，同时分析了两者相关性。结果表明：补铜前血浆铜在10.93 μmol/L以下者占被检牛数的54.55%（6/11），其血浆CP活性降低，两者呈现中度相关性（R2=0.53）；补铜后血浆铜含量与CP活性均极显著增高（P<0.01），血浆铜含量达到正常范围，两者呈现低相关性（R2=0.12）。〖JP〗结论：该奶牛场泌乳奶牛群中存在低铜血症病牛，血浆铜蓝蛋白可以作为奶牛低铜血症的一项检测指标。     

奶牛腐蹄病的病因及防制措施

通过对奶牛腐蹄病的病因、治疗、预防及控制等方面的综述,从日粮营养、环境卫生、饲养管理、遗传育种等诸多方面探讨,提出了实用有效的防制措施。     

利福昔明的药理作用及其在奶牛疾病防治中应用的研究进展

利福昔明是一种治疗奶牛疾病的新药,抗菌谱广,抗菌活性强,抗菌机制独特,无致突变、致畸、致癌及生殖毒性等,适合作为局部用药。作者综述了利福昔明的研究现状,并对其理化性质、作用机制、药动学、药理毒理学性质及在临床疾病防治中的应用进行了描述,为利福昔明在动物临床疾病防治应用方面提供理论依据,以便兽医工作者全面了解该药,进而指导其临床应用。     

Research Progress on Pharmacological Action of Rifaximin and its Application in Prevention and Treatment of Dairy Cow Disease

Rifaximin is a kind of new drug for the treatment of dairy cow disease which antimicrobial spectrum is wide.It has a strong antibacterial activity and unique antibacterial mechanism.Rifaximin is suit for local administration because it is no mutagenic,abnormal toxicity,carcinogenicity and reproduction toxicity and so on.In this paper,the physical and chemical properties,action mechanism,pharmacokinetic,pharmacology and toxicology properties,clinical application were investigated and reviewed,so as to provide a theoretical basis for the application in prevention and treatment of animal diseases,and make veterinary workers have a comprehensive understanding of rifaximin and guide the clinical application.     

阴离子型日粮及补Ca对围产期奶牛代谢与健康及其生产性能的影响

将36头干奶后期中国荷斯坦奶牛随机分为对照组、试验Ⅰ组、试验Ⅱ组（每组12头）．分别饲喂常规日粮、阴离子型日粮及在此基础上朴Ca日粮，探讨其对奶牛体内代谢状况、健康状况及生产性能的影响。与饲喂常规日粮相比，饲喂阴离子型日粮可降低奶牛尿液pH值（P〈0．01）和血液HCO2^-浓度（P〉0．05）；增加奶牛产后12h（P〈0．05）、2d（P〈0．05）血清总钙含量．对血清无机磷、镁含量没有显著影响；明显降低奶牛亚临床性低血钙率（33％）、胎衣不下率（33％）和乳房水肿率（17％）；增加牛奶乳糖率（P〈0．05），对其他奶成分和奶产量没有显著影响（P〉0．05）。在阴离子型日粮中补Ca后．与饲喂阴离子型日粮相比．除增加奶牛产后血清镁含量外（P〈0．05）．对其他各项指标没有明显影响。     

Comparison of the efficacy of macrocyclic lactone anthelmintics,either singly or in combination with other anthelmintic(s), in nine beef herds in southern NSW

Anthelmintic resistance (AR) is a well-recognized challenge in farmed ruminants. The use of anthelmintics in combination is one of the strategies recommended to slow the rate of AR development. Two studies were undertaken in 2017 and 2019 to assess the efficacy of single-dose macrocyclic lactone (ML) anthelmintic and ML combination drenches. In total, 11 Faecal Egg Count Reduction Trials (FECRTs) were set up in 10 different beef herds, with results available from 10 of those FECRTs (9 herds). AR to a single ML anthelmintic was detected in all 9 herds, with resistance to Cooperia and Haemonchus spp on 9 farms, and resistance to Ostertagia and Trichostrongylus spp on 2 farms. In contrast, for the ML combination anthelmintics, all FECRTs resulted in efficacies of 99%–100%. The results suggest that cattle producers should strongly consider using combination drenches in their herds in preference to single actives.     

奶牛卵巢囊肿分布调查及形成原因分析

为了探讨北京市规模化奶牛场奶牛卵巢囊肿的发病情况、致病因素及形成机制,本研究采用直肠检查及B超诊断,结合奶牛的胎次、分娩季节及血清生化指标、激素水平等分析了奶牛卵巢囊肿的分布情况、影响因素及形成原因。结果表明,卵巢囊肿在所试奶牛场的发病率为10.73%,不同胎次奶牛卵巢囊肿发病率不同;在所有卵巢囊肿奶牛中,夏季分娩奶牛（51.06%）明显高于春季（8.51%）和冬季（17.02%）;胰岛素、胰岛素样生长因子1（IGF-1）及雌二醇（E₂）等与奶牛卵巢囊肿的发生密切相关,其中患有卵巢囊肿奶牛血清胰岛素和IGF-1的平均浓度均显著低于正常奶牛血清值（P < 0.05）,而血清E₂的平均浓度却显著高于正常奶牛血清值（P < 0.05）。该研究结果为奶牛场奶牛卵巢囊肿的预防和治疗提供了可靠的依据。     

Investigation on the Distribution and Analysis on Formation Cause of Cystic Ovarian Disease in Dairy Cows

In order to explore the incidence,pathogenic factors and the formation mechanism of cystic ovarian disease (COD) in Beijing scale dairy farm,we used the rectal examination and ultrasound diagnosis,combined with the dairy parity,calving season and serum biochemical indices and hormone levels to investigate the distribution,influencing factors and formation cause of cow ovarian cysts.The results showed that the incidence of cystic ovarian disease (COD) was 10.73% in the testing dairy herds and the incidence of COD was associated with the parities.The incidence rate of ovarian cyst in the cows calving in the summer (51.06%) was higher than those calving in the spring (8.51%) and winter (17.02%).Insulin,IGF-1 and E₂ were closely related with the formation of the cow ovarian cyst.The average concentrations of serum insulin and IGF-1 in cows with ovarian cysts were significantly lower than those of normal cows(P < 0.05),but the average concentration of serum E₂ was significantly higher than that of normal cows(P < 0.05).This study provided reliable basis for the prevention and treatment of cow ovarian cyst.     

Effects of Rumen-protected Methionine on Rumen Fermentation,lactation Performance and Plasma Characteristics in Dairy Cows

The objective was to evaluate effects of rumen-protected methionine （RP-Met） supplementation on rumen fermentation, lactation performance and plasma characteristics in dairy cows. Twenty-four multiparous （2.2 - 0.40 parity） Holstein dairy cows, averaged 620 ± 12.3 kg of BW, 68 ± 2.5 day in milk and daily milk production averaged 26.0 ±0.3 kg/cow were used in a replicated 4 × 4 Latin square experiment. The treatments were： control （without RP-Met）, LRP-Met, MRP-Met and HRP-Met with 20, 40 and 60 g RP-Met per cow per day, respectively. RP-Met was hand-mixed into the top one-third of the daily ration. Experimental periods were 30 days with 15 d of adaptation and 15 d of sampling. Dry matter （DM） intake and milk yields were not affected （P 〉 0.05） with increasing RP-Met supplementation. Yields of 4%FCM, ECM, milk fat and milk protein were higher （P 〈 0.03） for RP-Met supplementation than control and were quadratically （P 〈 0.05） changed due to the higher percentage of milk fat and protein for RP-Met supplementation than control （P 〈 0.03）. Ruminal pH tended to be lower （P = 0.071） for RP-Met supplementation than control, whereas total VFA concentration tended to be higher （P = 0.086） for RP-Met supplementation than control. Ratio of acetate to propionate decreased linearly （P = 0.001） from 4.01 to 3.57 as RP-Met supplementation increased due to the increase in propionate production. Digestibilities of DM, OM, CP, NDF and ADF in the total tract were higher （P 〈 0.05） for RP-Met supplementation than control and were quadratically （P 〈 0.05） increased with increasing RP-Met supplementation. Plasma concentrations of glucose not affected （P 〉 0.05） with RP-Met supplementation, Plasma concentrations of non-esterified fatty acids （NEFA） were significantly lower （P = 0.017） for RP-Met supplementation than control and were linearly （P = 0.011） changed. Plasma concentrations of beta-hydroxybutyrate tended to be lower （P = 0.068） for RP-Met supplementation than control and were linearly （P = 0.001） changed. The present results indicate that supplementation of diet with RP-Met improved the content of milk fat and protein, rumen fermentation and feed digestion, decreased plasma concentrations of NEFA. It was suggested that the RP-Met stimulated the digestive microorganisms or enzymes in a dose-dependent manner. In the experimental conditions of this trial, the optimum RP-Met dose was about 25 g RP-Met per cow per day.     

草畜乳协调发展是建设现代奶业的必然选择

虽然当前奶业形势较为严峻,三鹿事件使中国奶业遭到重创,但决不能说中国奶业陷入无法自拔的困境,反而出现了新的契机。相对于世界畜牧业发达国家,我国在农区进行种草养牛尚未完全推广,而当前形势使其具有现实可能性,且势在必行。同时,我们要走出"草粮争地"的认识误区,制定并落实优惠政策,加强科技支撑,探讨可持续的运作模式。因此,草畜乳业的协调发展是建设现代奶业的必然选择。     

'Looking up' behavior in the holding area of the milking parlor: its relationship with step-kick, flight responses and productivity of commercial dairy cows

Commercial dairy cows milked in a parlor system are packed close together in the holding area before milking. The present study examined the relationships of ‘looking up’ behavior with some other behaviors and the productivity of 1116–1153 cows from five farms. The individual identities of the cows looking up in the holding area were recorded at 5 min intervals during six intermittent afternoon milking sessions. Entrance into the milking parlor and the numbers of steps and kicks by cows while the milking person was attaching the milking cups, were recorded in six milking sessions. Flight responses in the pasture after milking were recorded over four days intermittently. The frequency of ‘looking up’ behavior weakly, but significantly correlated with flight starting distance (r = 0.10, P < 0.05), while the correlation with the number of step‐kicks during milking was not significant. As for productivity, lactation number (r = ?0.18, P < 0.001), milk yield (r = ?0.15, P < 0.001) and fat content (r = ?0.15, P < 0.001) were negatively correlated with the frequency of ‘looking up’ behavior. Age of cows was correlated with the frequency of ‘looking up’ behavior as well as lactation number (r = ?0.21, P < 0.001). Entrance order was positively correlated with the frequency of ‘looking up’ behavior (r = 0.15, P < 0.001). The ‘looking up’ behavior was observed more frequently in cows in their third or less lactation compared with cows which were in their fourth or greater lactation (P < 0.05). The lactation number of cows was correlated with their milk yield (r = 0.36, P < 0.001) and flight starting distance (r = ?0.21, P < 0.001). In conclusion, ‘looking up’ behavior shown by cows in the holding area before milking might be an indicator of low motivation for milking, mainly because of fear of humans, and an aversion to milking caused by insufficient experience in being milked.     

中国规模化牧场后备奶牛疾病与淘汰现状

后备奶牛健康生长对其未来生产性能具有重要影响.调研结果表明,呼吸系统疾病和营养代谢疾病是导致后备奶牛发病的主要原因,占比分别为46.0％和38.4％.而后备奶牛中发病最多的为哺乳犊牛,占比达51.4％.目前,哺乳犊牛发病率正在逐年降低,从2015年的43.3％降至2019年的25.4％.此外调研发现,造成后备奶牛被动淘...     

乳酸在奶牛体内的代谢途径及其对奶牛健康影响的研究进展

乳酸（lactic acid）是奶牛瘤胃内重要的中间代谢产物,合理的调节乳酸代谢特征、充分利用及发挥乳酸的有益功能对奶牛健康生产具有重要意义。文章介绍了乳酸的合成途径及主要产酸菌、乳酸的代谢途径及主要利用菌、乳酸在奶牛瘤胃内的代谢方式及影响其代谢的因素,详细阐述了乳酸产生菌与利用菌对乳酸代谢调节的影响,同时介绍了植物提取物对乳酸代谢调节作用及乳酸代谢调节对奶牛胃肠道菌群、泌乳性能和乳房炎的影响。为进一步了解乳酸对奶牛健康的作用机制及相关植物活性物质在生产实践中的应用提供理论依据,为解决高精料饲粮引起的奶牛酸中毒的预防与治疗提供新思路。     

日粮阴阳离子差对奶牛的影响及其在生产实践中的应用研究进展

阴阳离子差(DCAD)是指日粮中每千克或每百克干物质所含的主要阳离子（Na⁺、K⁺、Ca²⁺、Mg²⁺）毫摩尔数与主要阴离子（Cl^-、S^2-、PO^3-₄）毫摩尔数之差。DCAD直接影响奶牛血液的酸碱平衡及酶系统等的功能，可以改善奶牛的健康状况、提高奶牛生产性能。在此，作者综述了国内外关于调节日粮阴阳离子差对奶牛影响的研究结果及现状，探讨了DCAD在奶牛不同阶段生产实践中的应用。     

黑龙江省鸡西地区奶牛子宫内膜炎病原菌分离鉴定及耐药性研究

从黑龙江省鸡西地区部分奶牛场选取25头临床诊断为子宫内膜炎的患牛,并从这25头患牛体内分离得到39株细菌,其中大肠杆菌17株、葡萄球菌13株、链球菌5株、其他菌4株。耐药性试验表明,大肠杆菌、葡萄球菌和链球菌都对头孢曲松钠和头孢噻呋钠敏感,对庆大霉素比较敏感,对其他几种常用抗生素存在不同程度耐药性。     

微生态制剂对奶牛产奶量和乳品质与肠道菌群的影响

通过在奶牛饲粮中添加微生态制剂,研究其对奶牛产奶量、乳品质和肠道菌群的影响。试验从200头成年产奶牛中,选取20头年龄、胎次、泌乳月份、妊娠期、产奶量、体重基本相似且身体健康的荷斯坦奶牛,分为试验组和对照组,试验期为35 d。其中对照组按照常规方式饲养,试验组在精料中按1‰的比例加入复合微生态制剂。结果表明:对照组奶牛平均产奶量降低,每头日均产奶量减少0.36 kg(P>0.05),而试验组每头日均产奶量比对照组增加1.81 kg,增产16.97%,差异极显著(P<0.01);与对照组相比,试验组蛋白质、乳糖和非脂乳固体增加,但差异不显著(P>0.05),脂肪降低(P<0.05);最后采用PCR-DGGE技术分析奶牛肠道菌群,结果试验组肠道菌群多样性明显高于对照组,且相似性达到97%,证实微生态制剂具有调节奶牛肠道菌群平衡的作用。     

不同形式的植物油对奶牛生产性能和瘤胃微生物区系的影响

试验研究了日粮中分别补充0(对照组)、2%亚麻籽油(亚麻籽油组)、2%大豆油(大豆油组)和等同2%植物油的10%膨化大豆(膨化大豆组)对奶牛生产性能和瘤胃微生物区系的影响。结果表明:饲喂亚麻油、大豆油和膨化大豆组奶牛的奶产量显著(P<0.05)高于对照组,而乳脂含量显著低于对照组(P<0.05),校正乳(FCM)产量各组间差异不显著(P>0.05)。饲喂亚麻油、大豆油或膨化大豆对奶牛瘤胃微生物图谱条带数量和区系的相似性指数无显著影响(P>0.05)。各处理组的白色瘤胃球菌、溶纤维丁酸弧菌和产琥珀酸丝状杆菌比例无显著性差异(P>0.05)。研究结果显示,日粮补充适宜水平的不同形式植物油可改善奶牛生产性能,但对瘤胃微生物区系无显著影响。     

同期排卵处理母牛体温和活动量变化规律及效果分析

为探究同期排卵处理母牛体温和活动量变化规律及不同同期排卵技术处理效果,指导同期排卵技术优化。本研究自动监测了18头20月龄左右同期排卵（GnRH-PG-GnRH）处理荷斯坦母牛和17头产后40~60 d预同期排卵（PG-PG-GnRH-PG-GnRH）处理荷斯坦母牛的体温和活动量,应用自动检测系统进行母牛发情监测。结果发现,同期排卵处理母牛发情时阴道温度平均升高（0.43±0.20）℃,持续（12.37±2.73）h;活动量平均升高（18.28±18.61）倍,持续（11.00±1.68）h;排卵时阴道温度平均下降（0.20±0.10）℃,持续（11.00±1.68）h。自动化发情监测显示,同期排卵处理母牛7头发情并排卵;预同期排卵母牛GnRH处理前全部发情排卵。两种同期排卵处理,虽可改变母牛性周期进程,促进母牛性周期同步化,但均难以使母牛性周期完全同步。因此,将同期排卵-定时输精和发情鉴定技术科学结合才能取得更好的繁殖效果。     

理囊散对不孕奶牛血清中微量元素和白介素影响的研究

本试验旨在探讨经理囊散治疗不孕症奶牛前后,血清中微量元素(Cu、Fe、Mn、Zn)与白介素(IL-1、IL-6)的含量变化规律。利用火焰法原子吸收光谱法和酶联免疫吸附法分别检测试验组和对照组治疗前、后血清中微量元素和白介素的含量。试验结果表明,①理囊散治疗卵泡囊肿有效率为83.33%,排卵延迟有效率为90.91%;②在卵泡囊肿型奶牛中,Mn、Zn含量治疗前均显著低于正常组(P<0.05),Fe治疗前显著高于正常组(P<0.05),经治疗后逐渐达到正常值水平,Cu、IL-1、IL-6含量治疗前后差异不显著;③在排卵延迟型奶牛中,Fe治疗前显著高于正常组(P<0.05),Mn含量治疗前极显著低于正常组(P<0.01),Zn含量治疗前显著低于正常组(P<0.05),经治疗后逐渐达到正常值水平,Cu、IL-1、IL-6含量治疗前后差异不显著。因此,理囊散对奶牛不孕症血清中部分微量元素和白介素含量有微调作用,在奶牛不孕症治疗效果上有不可忽视的作用。