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1.
益生菌枯草芽孢杆菌发酵培养基及条件的优化   总被引:4,自引:0,他引:4  
试验对枯草芽孢杆菌4#的发酵培养基和发酵条件进行筛选优化.通过单因素试验及正交试验方法,确定该枯草芽孢杆菌4#的优化培养基为0.5 %葡萄糖、0.3 %淀粉、3 %豆粕、3.08 %硫酸锰0.2 mL、0.3 %磷酸氢二钾、0.15 %磷酸二氢钾、0.05 %硫酸镁、0.02 %酵母膏、0.01 %氯化铁和0.01 %碳酸钙.最适发酵条件为初始pH 7.2,发酵温度30 ℃,摇床转速220 r/min,接种量10 %.进行发酵罐放大培养,最佳放罐时间18~20 h,获得的菌体数量约128亿个/mL.  相似文献   

2.
本试验以蚕沙为原料,利用米曲霉发酵生产果胶酶,通过单因素试验和正交设计试验对产酶条件进行了优化,试验结果显示:在培养基初始pH为自然,蚕沙添加量为4%,接种量4%,发酵温度36℃,发酵时间96 h的培养条件下,测得酶活为131.3 U/mL,比初始培养条件的酶活力提高了229%。  相似文献   

3.
通过试验研究了一株产乳糖酶脆壁克鲁维酵母的发酵培养基成分及培养条件,最终确定了该株酵母的最佳发酵培养条件.结果表明,此株脆壁克鲁维酵母发酵生产乳糖酶的最佳培养基成分为:乳糖4%,酵母粉3%,MnCl2 1mmol/mL;最佳培养条件:接种量10%,温度28°C,初始pH 7-7.5,摇床转数180 r/min,培养时间36 h.在此条件下培养,乳糖酶活力达1100 u/mL或4140 u/g干菌体.  相似文献   

4.
益生菌酪酸菌CB-7发酵培养基及培养条件的研究   总被引:2,自引:0,他引:2  
通过单因子试验及正交试验对酪酸菌CB-7发酵培养基和培养条件进行研究.结果表明,最优化培养基组成为玉米淀粉1.0 %,牛肉蛋白胨1.0 %,酵母膏0.5 %,乙酸钠0.3 %,NaC1 0.5 %,CaCO3 0.3 %,MgSO4*7H2O 0.05 %.确定最佳培养条件为初始pH 7.0,培养温度37 ℃,接种量7.5 %,培养36 h,菌体浓度可达8.5×108 CFU/mL,芽孢率可达95.3 %.  相似文献   

5.
《中国兽医学报》2017,(12):2397-2401
旨在研究2株枯草芽孢杆菌协同降解黄曲霉毒B1(AFB1)的作用。将2株枯草芽孢杆菌进行生理生化特性鉴定和16SrRNA序列测定后,以AFB1降解率为依据,分别进行优化培养并观察协同降解作用。结果表明:菌株K-3优化条件为装液量50mL/250mL、温度37℃、4%接种量、初始pH7.0、发酵周期48h,150r/min振荡培养,对AFB1降解率为88.07%(P<0.05);菌株K-TM装液量为50mL/250mL、温度37℃、6%接种量、初始pH7.0、发酵周期60h,150r/min振荡培养,对AFB1降解率为84.81%(P<0.05);K-3、K-TM按体积1∶2组合,对AFB1协同降解率达到88.43%。本研究为益生菌在降解黄曲霉毒素中的应用奠定理论基础及试验依据。  相似文献   

6.
为了进一步提高枯草芽孢杆菌JNB001产蛋白酶的能力,试验利用单因素及正交试验从起始pH、发酵温度、接种量、装液量、菌龄等方面对产酶条件进行优化。结果表明,最佳培养条件为:起始pH 7.0;发酵温度35℃;接种量7%;装液量35mL/250mL;菌龄18h;发酵时间36h。菌株JNB001经优化发酵条件后,测定其蛋白酶活力可高达371.66U/mL。该试验结果为无害化生物处理罐的优化设计等后续应用研究奠定了基础。  相似文献   

7.
微生物发酵法生产大豆肽工艺条件的研究   总被引:1,自引:0,他引:1  
以脱脂豆粕为原料,采用地衣芽孢杆菌发酵生产大豆肽.研究菌株种龄、种子液接种量和摇床速度对多肽产量的影响,结果表明,种龄12 h,接种量5%,摇床速度180 r/min最佳.同时,对影响多肽产量的发酵温度、发酵时间及豆粕粉加水量3个主要因素用正交试验方法进行优化,正交试验结果发现,该菌株发酵产多肽的最佳条件为温度37℃,发酵时间48 h,加水量94%.优化后该菌株发酵豆粕后的多肽溶液酸性可溶氮含量达到1 384.65μg/mL,水解度DH为23.89%.  相似文献   

8.
为了多元化开发利用桑叶蛋白质资源,将桑叶粉用枯草芽孢杆菌发酵制备桑叶蛋白。以桑叶蛋白得率为响应值,通过Plackett-Burman试验设计、最陡爬坡试验和Box-Behnken试验设计对桑叶发酵条件进行优化,并对发酵后桑叶蛋白的体外消化能力进行评价。结果表明,桑叶粉质量浓度、装液量、蔗糖质量浓度和发酵时间对桑叶蛋白得率具有显著影响(P<0.05),其影响大小依次为桑叶粉质量浓度>装液量>蔗糖质量浓度>发酵时间,发酵最优条件为桑叶粉质量浓度2.64mg/mL、装液量105 mL、蔗糖质量浓度22 mg/mL、发酵时间45.1 h。在此优化条件下,桑叶蛋白得率的预测值为16.43%,验证值为16.29%,试验结果重现性良好,建立的桑叶蛋白得率与主要发酵条件因子的数学回归模型可靠。体外消化试验表明,该方法制备桑叶蛋白的体外消化能力得到显著提高(P<0.05),体外消化率比发酵前提高了4.29个百分点。  相似文献   

9.
通过单因素试验和正交优化试验,对枯草芽孢杆菌产中性蛋白酶的发酵条件进行优化。通过单因素试验表明,枯草芽孢杆菌产中性蛋白酶的最佳碳源、氮源、无机盐种类、碳源添加量、氮源添加量、发酵温度和初始pH值分别为麦芽糖、蛋白胨、氯化钙、麦芽糖添加量8%、蛋白胨添加量4%、发酵温度37℃、初始pH值7.0。在单因素试验的基础上进行正交优化试验得到了枯草芽孢杆菌产中性蛋白酶最优发酵条件为:麦芽糖添加量8%、蛋白胨添加量8%、氯化钙添加量8 g/L、发酵温度37℃、初始pH值7.0。在最优发酵条件下,枯草芽孢杆菌所产的中性蛋白酶酶活为420.36 U/mL,比优化前98.36 U/mL提高了3倍。  相似文献   

10.
为了筛选出能够有效防止畜禽呼吸道疾病的益生菌发酵中草药制剂,对3个不同的组方进行发酵菌株的筛选及止咳化痰效果的对比。3个自拟组方分别为组方1(F1)、组方2(F2)、组方3(F3),通过最优发酵菌株的筛选、最佳发酵时间、最佳中药添加量的摸索试验,获得3个组方的最佳发酵条件,再利用小鼠氨水引咳法及酚红排泄法对3个发酵制剂进行效果对比试验-结果显示,3个组方的最佳菌液接种量为4%;中药水提液(0.5 g/mL)添加量为20%,发酵温度37℃,发酵时间为20 h;F2可显著延长小鼠的咳嗽潜伏期(P0.05),减少5 min内的咳嗽次数(P0.05);能明显增加小鼠气管的酚红排泄量,提高小鼠的化痰效果。3个不同的乳酸菌发酵中药组方中,组方2的止咳化痰作用最强,可用于进一步的试验研究。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
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   

13.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

14.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

15.
16.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

17.
The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.  相似文献   

18.
Bovine Mastitis in Selected Areas of Southern Ethiopia   总被引:3,自引:0,他引:3  
A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.  相似文献   

19.
不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响   总被引:2,自引:0,他引:2  
本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。  相似文献   

20.
A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.  相似文献   

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