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1.
我国奶牛养殖规模不断扩大,奶业产值比重逐步提高,给奶牛疫病防治带来巨大压力。奶牛乳房炎及细菌性肺炎等呼吸系统疾病和细菌性肠炎等消化系统疾病最为常见,抗菌药物的使用成为主要防治手段。但抗菌药物的不当使用易使细菌产生耐药性,增加临床治疗的成本和难度,危害我国奶牛产业发展。本文对截至2021年7月我国和美国、英国、日本、欧盟批准用于奶牛的抗菌药物产品进行整理、统计与分析,包括抗菌药物的分类、剂型以及适应证等,旨在为我国奶牛用抗菌药物管理、合理用药和新兽药开发提供参考。  相似文献   
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为了筛选适宜的种公牛用于新疆褐牛肉用类型选育及群体杂交改良,选择两个家系的12、18、24月龄种公牛后代120头,比较分析其后代的超声波活体测定、体重、体尺等各项指标,结果表明:188号公牛后代12、18、24月龄背膘、眼高、12-13肋QIB、眼肌面积与4008号公牛后代差异均不显著(P>0.05),12月龄、18月龄、24月龄体重显著大于4008号公牛后代(P<0.05),12月龄、24月龄体高和18月龄体斜长、尻长显著高于4008号公牛后代(P<0.05),12月龄、24月龄胸围、尻长极显著高于4008号公牛后代(P<0.01)。结论:188号公牛后代产肉性能、尻部发育、体格等各项性能指标均好于4008号公牛后代,将188号公牛定位首选种公牛。  相似文献   
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《Ticks and Tick》2020,11(4):101438
Chemical tick control is a major means of preventing East Coast fever (ECF), especially in sub-Saharan Africa. However, in southwestern Uganda, improper tick control practices have led to severe acaricide resistance. The objectives of this study were to determine the risk factors associated with tick infestation in dairy cattle and Theileria parva infection, and to generate evidence for the prioritization of effective countermeasures for tick control. A cross-sectional study was conducted in 30 farms in Mbarara District, and information on tick control practices and tick infestation were collected. Tick samples were collected from 13 farms to test tick acaricide efficacy. A total of 420 blood samples from calves to adults of exotic- and cross-breed dairy cattle were collected, and T. parva diagnosis via polymerase chain reaction was performed. All the 13 tick populations tested were resistant to deltamethrin (synthetic pyrethroid). Resistance to single-formulation organophosphate-chlorfenvinphos was 39 % (5/13); co-formulations (chlorpyrifos + cypermethrin), 69 % (9/13); and amitraz (amidine), 85 % (11/13). The overall prevalence of T. parva infection at the individual-level was 45.2 % (190/420, 95 % confidence interval (CI): 40.4–50.1), and that at the farm-level was 83 % (25/30, 95 %CI: 65–94). A good quality cattle crush was a preventive factor for tick infestation (odds ratio (OR): 0.32, 95 %CI: 0.15−0.63, p = 0.001). Well-managed acaricide storage (OR: 0.36, 95 %CI: 0.17−0.76, p = 0.008), and a good quality measuring cylinder for acaricide were preventive factors (OR: 0.32, 95 %CI: 0.11−0.93, p = 0.036) for T. parva infection. The risk factors for T. parva infection were a longer period of acaricide use of the same brand (OR: 1.06, 95 %CI: 1.01−1.10, p = 0.012), and a higher frequency (twice a week) of acaricide use rather than once a week (OR: 11.70, 95 %CI: 1.95−70.13, p = 0.007). These risk factors should be given high intervention priority in order to effectively control ticks and prevent T. parva infections in dairy farms. Teaching proper practices to dairy farmers and to technical staff should be used to overcome the severe challenge of acaricide resistance in Mbarara District.  相似文献   
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A major risk factor for the spread of livestock diseases and their vectors is the uncontrolled transboundary movement of live animals for trade and grazing. Such movements constrain effective control of tick‐transmitted pathogens, including Theileria parva. Only limited studies have been undertaken to identify ticks and tick‐borne diseases (TTBDs) affecting cattle in central African countries, including Cameroon. We hereby report the collection of baseline data on the prevalence of T. parva in Cameroon through a countrywide cross‐sectional survey, conducted in 2016, involving collection of blood samples from cattle from 63 sites across the five agro‐ecological zones (AEZs) of the country. ELISA‐based surveillance of infected cattle was performed on 479 randomly selected samples and revealed specific antibodies to T. parva in 22.7% and T. mutans in 41.1% of cattle. Screening of 1,340 representative DNA samples for the presence of T. parva identified 25 (1.86%) positives using a p104 antigen gene‐based nested PCR assay. The positives were distributed across agro‐ecological zones I, II, III and V. None of the p104 positive cattle exhibited clinical symptoms of East Coast fever (ECF). Using reverse line blot (RLB), 58 (4.3%) and 1,139 (85%) of the samples reacted with the T. parva and T. mutans oligonucleotide probes, respectively. This represents the first report of T. parva from Cameroon. Surprisingly, no Rhipicephalus appendiculatus ticks, the main vector of T. parva, were identified in a parallel study involving comprehensive morphological and molecular survey of tick species present in the country. Only two of the 25 p104 positive cattle were PCR‐positive for the CD8+ T‐cell target schizont‐expressed antigen gene Tp1. Cloning and sequencing of Tp1 amplicons revealed sequence identity with the reference T. parva Muguga. This new finding raises serious concerns of a potential spread of ECF into the central African region.  相似文献   
6.
试验旨在分析塔额垦区放牧饲养夏洛莱牛肉氨基酸组成含量及营养成分,为夏洛莱牛肉品质分析及改良当地土牛提供科学依据。试验选取体重500±45 kg的夏洛莱肉牛(公母各半),采集里脊、眼肌、肩肉、上脑、胸肉5个部位,分别测定其营养物质及氨基酸组成含量,并参照FAO/WHO模式进行氨基酸评分。结果显示,样品中水分含量公牛和母牛分别为73.10%和64.14%,符合国家标准,粗脂肪含量公牛最低为0.14%。检测出17种氨基酸,非必须氨基酸中天冬氨酸含量最高,公牛和母牛分别为30.74%和29.02%,其次为谷氨酸,分别为11.38%和10.73%,提示夏洛莱牛肉鲜味有降低的趋势。必须氨基酸中赖氨酸含量最高,公牛和母牛分别为9.23%和8.71%。母牛里脊中总氨基酸含量最低(P<0.05),为89.10%。氨基酸评分显示公牛EAA/TAA及EAA/NEAA分别为33.32%和50.00%,母牛EAA/TAA及EAA/NEAA分别为33.60%和50.62%,与FAO/WHO模式推荐量(EAA/TAA 40%,EAA/NEAA 60%)有一定差距,但可满足成人每日氨基酸需求量(EAA/TAA 27.3%,EAA/NEAA 37.5%)。综上,夏洛莱牛肉营养较好,品质中上,考虑其出肉量多的特点可以针对性的育肥或杂交改良。  相似文献   
7.
In 2018, a strain of epizootic hemorrhagic disease virus (EHDV), named YNDH/V079/2018, was isolated from a sentinel calf in Mangshi County, Yunnan Province, China. Nucleotide sequencing and neutralization tests indicated that the virus belongs to a novel serotype of EHDV that had not been reported previously.  相似文献   
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目的 掌握广西地区牛羊场硬蜱种类及其分子特征,了解该地区蜱类的分类地位,为养殖户防控硬蜱及蜱媒传染病提供参考依据。方法 本实验于2019年1月至2021年11月,采用动物体表法采集寄生的蜱类;提取蜱基因组,PCR扩增3种硬蜱的线粒体16S rDNA 和COI基因片段,并进行同源性分析。基于邻接法,用MEGA6.0软件分别构建系统发生树,进行遗传进化分析。结果 牛羊体表上共采集蜱2 030只,隶属1科2 属3种,其中微小扇头蜱1 968只,长角血蜱49只,具角血蜱13只。PCR扩增微小扇头蜱、长角血蜱和具角血蜱16S rDNA 和COI基因片段长度分别是460 bp和710 bp左右,分别与GenBank 中已登录的相应种类相似较高且在一个进化分支上。结论 广西地区牛羊场优势蜱种是微小扇头蜱且存在长角血蜱和具角血蜱。三蜱种16S rDNA 和COI序列存在多样性和地域差异性。  相似文献   
9.
背景 研究表明小梁网组织的氧化应激损伤是开角型青光眼的基本病理过程之一,莱菔硫烷(SFN)可通过激活Nrf2/ARE通路发挥其抗氧化应激作用,但其是否可对氧化应激损伤的小梁细胞发挥作用目前尚不清楚. 目的 探讨SFN对H2O2诱导的牛眼小梁细胞氧化应激损伤的防护作用. 方法 采用组织块培养法对新鲜摘取的黑牛眼球小梁组织进行小梁细胞原代培养,将第3代牛小梁细胞以1x 103/孔的细胞密度接种于96孔板中培养24 h后将细胞分为4个组,空白对照组加入100μl无血清培养基,H2O2组细胞在空白对照组的基础上加入100 μl终浓度为100 μmol/L H2O2建立细胞氧化应激损伤模型,SFN组在培养液中加入100μl终浓度为10μmol/L SFN,而SFN+H2O2组在SFN组的基础上加入100 μmol/L H2O2,细胞培养后6h采用CCK-8法检测各组牛眼小梁细胞活力,采用Annexin V-FITC/PI双染流式细胞仪检测各组细胞的凋亡率.结果 传至第3代的细胞呈梭形,形状和大小较均一,细胞质丰富,可见色素颗粒,核仁大.H2O2组和SFN+H2O2组相对细胞活力分别为空白对照组的(67.00±1.27)%和(80.00±6.25)%,其中SFN+H2O2组相对细胞活力低于空白对照组和SFN组,但明显高于H2O2组,差异均有统计学意义(均P<0.01).空白对照组、H2O2组、SFN组和SFN+H2O2组细胞凋亡率分别为(11.33±0.77)%、(32.31±1.03)%、(10.44±0.68)%和(17.68±0.21)%,各组间总体比较差异均有统计学意义(F-539.96,P<0.01),其中SFN+H2O2组细胞凋亡率明显低于H2O2组但高于空白对照组和SFN组,差异均有统计学意义(均P<0.01).结论 SFN可以增强H2O2诱导的牛眼小梁细胞的抗氧化应激能力,减轻氧化应激对牛眼小梁细胞的损伤.  相似文献   
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Haemorrhagic septicaemia (HS) is an acute fatal infectious disease of mainly cattle and buffalo and outbreaks occur commonly in Cambodia. Disease outbreak reports were examined to select five villages from three provinces for a retrospective investigation of HS epidemiology and socioeconomic impact on smallholders, with an aim of identifying potential benefits from improving disease prevention through biosecurity and vaccination. The Village Animal Health Worker (VAHW) or Chief in each village and 66 affected smallholders were surveyed. At the village level, 24% of all households were affected with an estimated mean village herd morbidity of 10.1% and mortality of 28.8%. Affected farmers reported HS disease morbidity and mortality at 42.7% and 63.6% respectively. Buffalo had a higher morbidity (OR = 2.3; = 0.003) and mortality (OR = 6.9; < 0.001) compared with cattle, and unvaccinated large ruminants a higher morbidity (OR = 2.9; = 0.001). The financial impact varied depending on whether the animal survived, provision of treatment, draught replacement and lost secondary income. The mean cost per affected household was USD 952.50 based on ownership of five large ruminants. The impact per affected animal was USD 375.00, reducing the pre‐disease value by 66.1%. A partial budget revealed an overwhelming incentive for farmers to practice biannual vaccination, with a net benefit of USD 951.58 per household based on an annual disease incidence rate of 1. Sensitivity analysis showed that a net benefit of USD 32.42 remained based on an outbreak every 20 years. This study indicates HS can cause a catastrophic financial shock to smallholders and remains a critical constraint to improving large ruminant productivity and profitability. Addressing HS disease control requires a focus on improving smallholder farmer knowledge of biosecurity and vaccination and should be priority to stakeholders interested in addressing regional food insecurity and poverty reduction.  相似文献   
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