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1.
Ruimin Chao Chengqiang Xia Caixia Pei Wenjie Huo Qiang Liu Chunxiang Zhang Youshe Ren 《Journal of animal physiology and animal nutrition》2021,105(1):26-34
The objective of this study was to investigate the characteristics of ruminal microbial communities of alpacas (Lama pacos) and sheep (Ovis aries) fed three diets with varying ratios of roughage (corn stalk) to concentrate, 3:7 (LS), 5:5 (MS) and 7:3 (HS). Six alpacas (one-year-old and weighing 29.5 ± 7.1 kg) and six sheep (one-year-old and weighing 27.9 ± 2.7 kg) were used in this study, in a replicated 3 × 3 Latin square experiment. Total protozoa concentration was determined under the microscope; total fungi and methanogens were assessed using quantitative polymerase chain reaction and expressed as a percentage of total bacterial 16S rRNA gene copies; bacterial communities were investigated by targeted 16S rRNA gene (V3–V4 region) sequencing. The percentage of fungi was significantly higher in alpacas than in sheep under the LS diet, while the concentration of protozoa was significantly lower in alpacas under HS, MS and LS diets. The alpha diversity including Shannon, Chao l and ACE indices of bacterial communities was higher in alpacas than in sheep, under the LS diet. A total of 299 genera belonging to 22 phyla were observed in the forestomach of alpaca and sheep, with Bacteroidetes and Firmicutes dominating both animal species. Phyla Armatimonadetes and Fusobacteria, as well as 64 genera, were detected only in alpacas, whereas phyla Acidobacteria and Nitrospira, as well as 44 genera, were found only in sheep. The abundance of cellulolytic bacteria, including Butyrivibrio and Pseudobutyrivibrio, was higher in alpacas than in sheep under all three diets. These differences in the forestomach microbial communities partly explained why alpacas displayed a higher poor-quality roughage digestibility, and a lower methane production. Results also revealed that the adverse effects of high-concentrate diets (70%) were lesser in alpacas than in sheep. 相似文献
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为评价警犬的狂犬病免疫效果,了解影响免疫效果的因素,2017年在云南、贵州、四川三省部分地区免疫狂犬病疫苗的警犬中随机抽样,采用荧光抗体病毒中和试验(FAVN),检测血清中狂犬病病毒中和抗体效价。结果显示,共抽检187只警犬,中和抗体阳性127只(≥0.50 IU/m L),总体免疫合格率为67.91%,其中云南、贵州、四川3省的免疫合格率分别为57.14%、68.33%、76.06%。结果分析表明,警犬狂犬病免疫合格率与犬的年龄、免疫次数、疫苗类型等因素有关,而与性别和品种无关。建议完善警犬免疫程序,加大血清中和抗体监测力度,对不合格警犬及时加强免疫;对每个影响因素进行连续性分析,以确定影响警犬狂犬病免疫合格率的具体因素。 相似文献
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WANG Huaqing GAO Qingshan JIANG Wenjie ZHAO Yuhan JIN Qingguo LI Yinghua XU Yongnan 《中国畜牧兽医》2019,46(2):497-503
To investigate the effect of histone deacetylation inhibitor Psammaplin A (PsA) on the development of bovine aging oocytes in vitro,oocytes were randomly divided into control group,aging group and 50 mmol/L PsA treated aging group (PsA group).Immunofluorescence staining and JC-1 were used to detect the blastocyst rate of bovine oocytes after parthenogenetic activation,the number of cells in blastocysts,apoptosis,reactive oxygen species (ROS),glutathione (GSH) and mitochondrial membrane potential intensity of embryos.The results showed that the blastocyst rate of the aging group was significantly lower than that of PsA and control groups (P<0.05).The blastocyst rate of PsA group was not significantly different from that of control group (P>0.05).The number of cells in the blastocysts of control group and PsA group were significantly higher than that of aging group (P<0.05).The number of cells in the blastocysts of PsA group was not significantly different from that of control group (P>0.05).The apoptosis rate in aging group was significantly higher than that of control and PsA groups (P<0.05),the apoptosis rate of PsA group was significantly higher than that of control group (P<0.05).The GSH level of MⅡ oocytes in aging group was significantly lower than that of control and PsA groups (P<0.05).There was no significant difference in GSH level between control and PsA groups (P>0.05).The ROS level of the embryos in aging group was significantly higher than that of control and PsA groups (P<0.05).The ROS level in PsA group was significantly higher than that of control group (P<0.05).The mitochondrial membrane potential of early embryos of aging group 4-8 cells was significantly lower than that of control and PsA groups (P<0.05).The mitochondrial membrane potential intensity of control group was significantly higher than that of PsA group (P<0.05).In summary,PsA could effectively delay the aging of bovine oocytes and improve the quality of oocytes. 相似文献
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β-胡萝卜素羟化酶(beta-carotene hydroxylase,BCH)是植物类胡萝卜素合成代谢中的关键限速酶,为获得烟草β-胡萝卜素羟化酶2(NtBCH2)基因序列,采用同源克隆法从烟草中分离NtBCH2的基因组DNA序列,基因登录号为JX101477。结果表明:1)同源克隆法从烟草中克隆出NtBCH2基因,NtBCH2基因组DNA全长2131bp,cDNA为1 083bp,含7个外显子和6个内含子。2)NtBCH2蛋白有309个氨基酸,分子量为34.79kD,具有7个糖基化位点,11个磷酸化位点,4个跨膜域。3)系统发育树与BLAST分析表明,NtBCH2是番茄的SlBCH和辣椒CaBCH2的同源基因;GENEVESTIGATOR数据库芯片结果表明,NtBCH2在幼嫩的茎和子叶中表达量最高。 相似文献
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中蜂囊状幼虫病是一种由中蜂囊状幼虫病毒引起的严重威胁中蜂健康的传染性疾病。目前由于该病尚无有效的药物治疗方式,因此,预防与及时检测对于遏制该病传播显得尤为重要。本文主要从临床诊断、分子生物学和免疫学方面总结中蜂囊状幼虫病检测与鉴定的方法,包括形态诊断、RT-PCR技术、实时荧光定量PCR、巢式PCR、胶体金免疫快速诊断技术、ELISA、血清学技术和基因芯片等,为中蜂囊状幼虫病毒检测方法的改进和优化提供参考。 相似文献
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为了解山东省牛羊疫病的流行及免疫现状,汇总2020年山东省牛羊疫病报告数据以及监测数据等信息,分析牛羊疫病的时间分布、空间分布及病种分布;结合监测情况,分析牛羊疫病的免疫状况和暴发风险。2020年山东省牛病以新生犊牛腹泻、牛病毒性腹泻和牛传染性鼻气管炎为主,突发输入性牛结节性皮肤病,羊病以沙门氏菌病、绵羊疥癣和布鲁氏菌病为主;牛病主要集中在鲁北和鲁西北地区,羊病主要集中在鲁中、鲁西、鲁南及半岛北部地区;牛羊疫病有一定的时间分布特征,7—9月份牛病暴发较频繁,6—9月和12月羊病发病率较高;口蹄疫、小反刍兽疫免疫水平较高,整体暴发风险可控,但仍存在一定的牛羊口蹄疫非结构蛋白抗体阳性;布鲁氏菌病免疫水平偏低,感染抗体阳性群体内个体感染情况较严重,羊群感染程度高于牛群。分析提示:鲁北和鲁西北地区应重点加强新生犊牛腹泻、牛病毒性腹泻等牛病的防控,鲁中、鲁西、鲁南及半岛北部地区应加强沙门氏菌病、布鲁氏菌病等羊病的防控,继续推进牛羊布鲁氏菌病净化场(县)创建工作;对口蹄疫和小反刍兽疫等防控效果较好的疫病以及新传入的牛结节性皮肤病,应持续加强免疫和监测,防止疫情传入或复发。 相似文献