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本文传达的信息是令人兴奋的，将基因工程技术应用于乳酸菌制剂，通过对一些优良菌种的遗传改造，导入有用基因如必需氨基酸合成酶基因、疫苗基因等，让乳酸菌制剂在肠道内就能产生必需氨基酸或某些传染病病原的免疫保护造。这将是最理想的乳酸菌制剂。而其基础是选择优良的乳酸菌，文章告诉说，他们通过从商品鸡盲肠当中分离出了6株乳酸菌，根据耐酸耐胆汁试验，病原菌生长抑制试验以及肠道粘膜粘附试验，筛选出两株优势菌株CX001和CX005。 相似文献
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转球虫SO7基因功能乳酸杆菌对肉仔鸡感染球虫后盲肠病理学变化的影响 总被引：2，自引：1，他引：2
为了检测转鸡柔嫩艾美耳球虫保护性抗原SO7基因的功能乳酸菌对试验感染球虫攻击的保护性,用含SO7基因的功能乳酸菌饲喂1日龄雏鸡,连喂11d后,以5×104个/只剂量接种球虫卵囊,通过观察雏鸡的组织病理学变化来评价转球虫SO7基因工程乳酸菌的效果。结果显示:饲喂转基因乳酸菌组雏鸡受球虫攻击的组织病理学变化最轻微。从而证明含保护性抗原SO7基因的功能乳酸菌对试验感染球虫攻击具有一定的保护性。本研究为外源性的保护性抗原基因在乳酸菌中表达用于球虫病的防治奠定了基础。 相似文献
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为构建乳酸菌Nisin诱导表达载体,实现外源目的基因在乳酸菌中的可控表达,本研究以产Nisin乳酸乳球菌染色体DNA为模板,采用PCR技术扩增双组份调控元件nisRK基因和诱导型启动子nisA基因,并克隆至乳酸菌-大肠杆菌穿梭质粒pW425et中,以nisA基因替换原组成型启动子P32,构建乳酸菌Nisin诱导表达载体pW425N。为检测载体的诱导表达功能,以gfp基因作为报告基因,构建重组表达载体pW425N-gfp,以分离自仔猪肠道内嗜酸乳杆菌为受体菌,电转化法制备重组乳酸菌pW425N-gfp/L.acidophilus。结果表明,重组载体能够在Nisin诱导下表达目的荧光蛋白,并且最佳Nisin有效浓度为30 ng/mL,最佳诱导时间为3 h。该表达载体的构建为外源功能性蛋白在乳酸菌中的诱导表达奠定基础。 相似文献
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综述了利用16S rRNA基因为靶基因的各种分子生物学技术来研究肠道中乳酸菌和双歧杆菌的方法，指出了肠道中乳酸菌和双歧杆菌的组成及其菌数。 相似文献
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乳酸菌以其安全、操作简单等优点被广泛用于表达外源基因,在食品、农业及医药工程领域,具有广阔的应用前景,开发了一系列乳酸菌食品级基因表达系统。目前已建立了糖诱导表达系统、噬菌体φ31暴发式诱导表达系统、乳链球菌素调控表达系统、温控表达系统等。随着基因工程技术的发展, 以重组乳酸菌作为基因工程菌的时代将要到来。 相似文献
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益生菌是一类有助于动物机体健康的微生物,在提高机体免疫力、改善肠道微生物平衡、促进养殖场环境等方面发挥重要作用。近年来,国内外学者对基因工程技术的探索已逐步深入,并在实际生产中加以应用。但是,目前为止绝大多数的研究将基因编辑技术着眼于真核生物。在此基础上,如何将基因编辑技术应用于益生菌,使益生菌发挥出更大的潜力是当前的研究热潮。因此通过基因工程技术将特定基因与益生菌进行基因编辑并表达,编辑后的益生菌可以表达特定的基因或者靶向对宿主发挥免疫调节作用。作者总结了基因编辑后的益生菌与宿主的相互作用,综述了CRISPR-Cas9技术在基因编辑乳酸菌及畜牧生产上的应用,同时经过分析比较不同基因编辑技术对乳酸菌进行基因编辑的方法,发现CRISPR-Cas9技术是目前针对乳酸菌和双歧杆菌等食品级益生菌相对灵活的基因编辑工具,能够实现益生菌在宿主体内发挥多重健康功效的目的,并对未来CRISPR-Cas9技术在基因编辑乳酸菌中的应用进行了展望,认为未来应将CRISPR-Cas9技术和其他基因编辑方法相结合,探索出更快更高效、简便的益生菌基因编辑技术。 相似文献
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《动物营养学报》2015,(9)
本试验旨在研究饲粮中添加不同水平转猪生长激素(PGH)基因乳酸菌对断奶仔猪生长性能、免疫指标、粪中微生物及养分消化率的影响。试验共选择160头体重(7.56±0.56)kg的(21±2)日龄断奶仔猪,分为4个组,每个组4个重复,每个重复(栏)10头仔猪。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加0.1%、0.2%、0.3%的转PGH基因乳酸菌,试验期为28d。结果表明:1)与对照组相比,饲粮添加转PGH基因乳酸菌极显著提高断奶仔猪的末重和平均日增重(P0.01),显著降低料重比(P0.05);极显著降低各试验组的腹泻率与腹泻指数(P0.01)。2)与对照组相比,饲粮添加0.1%转PGH基因乳酸菌可显著或极显著提高血清免疫球蛋白A与补体4含量(P0.05或P0.01)。3)与对照组相比,饲粮添加转PGH基因乳酸菌显著降低粪中大肠杆菌数量(P0.05);加0.1%转PGH基因乳酸菌组极显著增加乳酸杆菌数量(P0.01)。4)与对照组相比,饲粮添加0.1%转PGH基因乳酸菌极显著提高干物质与粗蛋白质表观消化率(P0.01),显著提高总磷表观消化率(P0.05)。综合分析,饲粮中添加转PGH基因乳酸菌可提高断奶仔猪的生长性能和养分表观消化率,提高免疫力,调节肠道菌群平衡;添加水平为0.1%时效果最佳。 相似文献
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试验旨在研究新疆伊犁牧区土壤－牧草－水(溪流)中铁、铜、锰、锌、硒5种微量元素的含量、分布特征与相互关系,以评估新疆伊犁夏牧场微量元素的营养生态环境。在伊犁夏牧场卡拉卓恩(南坡)和唐布拉草地(北坡)海拔1400~2999 m垂直带,根据海拔分别采取土壤(n=75)、牧草(n=75)和溪水(n=75)样品,测定其铁、铜、锰、锌和硒含量。结果表明,伊犁夏牧场土壤中铁、铜、锰和锌平均含量分别为15 418.4、32.6、474.5和115.8 mg/kg,牧草中分别为446.0、7.8、85.7和41.9 mg/kg,土壤与牧草铁、铜、锰和锌含量的相关性(R2)分别为0.43、0.82、0.47和0.72,土壤和牧草中铁、铜、锰、锌含量随海拔变化规律不明显;溪水中不含以上4种元素;土壤和牧草中不含硒,溪水含硒极微量。由此说明,伊犁夏牧场铁元素过多,锌、锰基本适宜,铜缺乏,而硒则严重缺乏。 相似文献
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SU Gui-long ZHANG Jing-yan ZHANG Kai WANG Lei ZHANG Kang WANG Xue-zhi YANG Zhi-qiang LI Jian-xi 《中国畜牧兽医》2017,44(6):1877-1883
The utilization of Astragalus resource was often limited to the root, while the stem and leaf had always been discarded, causing serious waste of traditional Chinese medicine resources. This experiment was aimed to study the changes of the content of active ingredients such as Astragalus polysaccharides, flavonoids and saponins in Astragalus root, stem and leaf by probiotic fermentation. A strain of FGM probiotic isolated from chicken intestines was used in this experiment for the fermentation of Astragalus root, stem and leaf. The results showed that, after fermentation, the crude polysaccharide contents of Astragalus root, annual stem, two years stem, annual leaf, two years leaf increased by 177.46%, 227.27%, 207.11%, 170.61% and 182.28%, respectively, the total flavonoids contents increased by 55.67%, 33.68%, 30.04%, -8.17% and -6.57%, respectively, and the total saponins contents increased by 68.50%, 55.91%, 55.71%, 40.93% and 46.13%, respectively. FGM probiotic fermentation made the main component contents of Astragalus increased, which would help for the further utilization of different parts of Astragalus, and efficient utilization of traditional Chinese medicine resources. 相似文献
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应用聚丙烯酸胺垂直板梯度凝胶电泳分析了进化水平不同的17种动物和人血清乳酸脱氢酶(LDH)同工酶.17种动物是鲤鱼、中华大蟾蜍、蝮蛇、罗斯蛋鸡、山鸡、紫貂、银狐、貉、梅花鹿、马鹿、黑白花奶牛、新疆细毛绵羊、猪、马、大耳白兔、昆明小鼠和猴.在同一凝胶板、同一条件下,对这些动物和人血清LDH同工酶谱分析表明,LDH同工酶谱在各类动物之间存在明显差异.进化比较低级的动物(杂交鲤鱼除外),血清LDH同工酶谱带迁移率较小,接近阴极;反之,进化比较高级的动物,同工酶谱带迁移率较大,接近阳极.亲缘关系相近的动物,LDH同工酶谱相似.表明LDH同工酶谱带的差异与动物间的亲缘关系有关.同种不同个体的动物LDH同工酶谱差异不明显,只有杂交鲤鱼个体LDH同工酶谱存在明显差异. 相似文献
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本试验通过研究伊犁夏牧场不同年龄、不同性别绵羊羊毛与血液中铁、铜、锰、锌、硒5种微量元素的含量及变化规律,为夏季放牧绵羊科学补饲微量元素提供依据。选择在新疆伊犁夏牧场卡拉卓恩(南坡)和唐布拉草地(北坡)1 400~2 999 m垂直带放牧的中国美利奴羊(新疆型)羊毛和血液样品,测定其铁、铜、锰、锌和硒含量,并评估其微量元素的营养生态环境。结果表明,放牧绵羊羊毛铁、铜、锰、锌和硒含量分别为520.70、3.89、30.16、102.64 mg/kg和41.18 μg/kg,其中铜和硒分别低于正常值48.3%和79.7%,而铁高于正常值603.4%;血液中铁、铜、锰、锌和硒含量分别为357.05、4.18、0.25、3.08 mg/L和45.23 μg/L,其中铜、硒分别低于正常值29.9%和73.9%,而铁高于正常值95.5%。羊毛与血液中铁、铜、锰、锌、硒含量均随年龄而增加。不同性别绵羊间血液中锌、硒含量差异明显。 相似文献
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为探讨犬常见肿瘤的发病规律，试验收集哈尔滨地区2016-2017年宠物医院部分犬肿瘤病例71例，采用组织病理学方法对犬肿瘤进行病理学诊断，并对患病动物的品种、性别、年龄、发生部位和饮食情况与肿瘤发生关系进行统计分析。结果显示，71例确诊肿瘤病例中，恶性肿瘤28例，包括鳞状上皮细胞癌3例，基底细胞癌5例，乳腺癌14例，淋巴瘤2例，肾母细胞瘤、精原细胞癌、生殖细胞癌、侵袭性血管黏液瘤各1例；良性肿瘤43例，包括良性乳腺肿瘤15例，纤维瘤10例，平滑肌瘤5例，乳头状瘤和精原细胞瘤各3例，造釉细胞瘤、耵聍腺瘤、脂肪瘤、结节样增生、性索间质细胞瘤、颗粒细胞瘤、肛周腺瘤各1例。上述病例中，乳腺和皮肤是犬肿瘤的高发部位，分别占全部患犬的40.8%和34.0%；患病犬年龄1~16岁不等，平均发病年龄为9.1岁，7岁以后是肿瘤的高发期，中老年犬仍为主要发病群体，但低龄犬发病数量上升；各品种犬均可发生肿瘤，其中杂种犬发病率最高，其次是贵宾犬和京巴犬，且主要为乳腺肿瘤；饮食习惯主要以剩饭剩菜类和肉拌饭类为主，分别占患犬总数的39%和30%；部分肿瘤类型与犬的性别、是否绝育有关，如乳腺肿瘤多发生于未绝育的老年母犬。本研究结果为犬肿瘤的流行病学及诊断提供了参考依据，对犬肿瘤的预防和诊断有一定的借鉴意义。 相似文献
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YANG Ju-qing LUO Qiu-jiang YANG Kai-lun ZHANG Guo-qing WANG Xiao XIE Peng-gui ZHANG Ji-rong 《中国畜牧兽医》2015,42(8):2048-2057
This experiment objective was to study the Fe, Cu, Mn, Zn, Se five kinds of trace element contents, distribution characteristics and mutual relations in the soil-grass-water (stream) in Yili pastoral area of Xinjiang, to evaluate the trace elements nutritional-ecologic environment of Yili summer pasture in Xinjiang.At the altitudinal belt of 1400 to 2999 m of the summer pasture of the Karajon grassland (South slope) and Tangbula grassland (North slope) of Yili, Xinjiang, the samples of soil (n=75), herbage (n=75), stream water (n=75) were collected according to the altitude, to determine their contents of Fe, Cu, Mn, Zn and Se for evaluating the nutritional-ecologic environment of trace elements of Yili summer pasture.The results showed that the contents of Fe, Cu, Mn, Zn in the soil of summer pasture on average were 15 418.4, 32.6, 474.5 and 115.8 mg/kg, respectively;And 446.0, 7.8, 85.7 and 41.9 mg/kg, respectively in forage;The correlation (R2) of the contents of Fe, Cu, Mn and Zn between soil and forage were 0.43, 0.82, 0.47 and 0.72, respectively;The changes of Fe, Cu, Mn and Zn contents in the soil and forage were not significantly related with the altitude.There were no the 4 elements mentioned above in river streams, there was no Se in the soil and forage, and there was infinitesimal of Se in the river streams.It was concluded that in Yili summer pasture there were excessive Fe, suitable Zn and Mn, insufficient Cu, and more insufficient Se. 相似文献
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选用川楝子治疗鸡球虫病及其对机体免疫力影响的研究,通过测定用药前后球虫虫卵数量的变化,以及测定用药前后血清和胸腺、脾脏、法氏囊组织匀浆中NO、NOS、SOD、MDA含量,结果为川楝子组血清和胸腺、脾脏、法氏囊组织匀浆中NO、NOS、SOD、MDA含量都较球虫感染对照组差异显著(P0.05)或差异极显著(P0.01);川楝子组对鸡免疫器官胸腺、脾、法氏囊指数指数均较球虫感染对照组差异显著或差异极显著。说明川楝子治疗鸡球虫病效果明显,且能够促进鸡免疫器官的发育和增强机体的免疫力,为研究驱杀球虫中药对免疫功能的影响提供了一种可行性的方法。 相似文献
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Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections
of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal
(GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April
2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs
located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming
areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology
laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum
columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying
degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal
abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy
season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different
nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those
observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes.
But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the
results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia. 相似文献