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1.
超滤法对牛初乳中IgG含量和活性的影响   总被引:3,自引:1,他引:2  
本文研究了超滤分离牛初乳乳清中IgG的方法,测定不同超滤温度和压力条件下IgG含量和活性的变化情况。结果表明:通过超滤可将乳清中IgG含量提高一倍左右;超滤压力增加,IgG含量相应增加.IgG活性基本不变。在压力0.08MPa时,IgG含量为45.98mg/mL,活性未变,仍为1024;超滤温度增加,初乳中的IgG含量先有较小增加然后减少,IgG活性则下降。在超滤温度40℃时,IgG含量最高,达到46、85mg/mL,IgG活性未有变化。  相似文献   

2.
温度和pH值对嗜热毛壳菌木聚糖酶活性影响的研究   总被引:2,自引:0,他引:2  
本试验采用DNS法,分别在温度为20.100℃,pH值2.4—7.2的条件下,研究了不同温度和pH值对嗜热毛壳菌木聚糖酶活性的影响。结果表明:温度在20—50℃时,木聚糖酶的活性随温度的升高而线性增强,40-60℃表现较高的水平,70—100℃活性逐渐稳定,并维持在20℃时的活性水平。说明动物体温为40℃左右时,木聚糖酶能表现出较高的活性;在制粒温度范围内,80℃热处理与未处理组木聚糖酶的活性比较损失不大,说明其在制粒工艺过程有一定的优势;在pH值3.6以前,随着pH值的增大,木聚糖酶的活性逐渐升高;pH值为3.6时,木聚糖酶的活性最高;且在3.2-4.4范围内木聚糖酶的活性维持较高浓度,说明消化道中食麇从胃的酸性环境转化成十二指肠后段碱性环境的过渡时期,木聚糖酶能表现出较高的活性,有利于促进其对底物的降解,从而提高营养物质的消化吸收。本研究得出:嗜热毛壳菌木聚糖酶在40-60℃表现较高的水平,实验室条件下的100℃以内的加热不会导致酶活性的严重损失。维持嗜热毛壳菌木聚糖酶活性的适宜的pH值范围为3.2—4.4。  相似文献   

3.
抗ETEC F18+菌毛特异性IgY的稳定性研究   总被引:1,自引:1,他引:1  
用间接ELESA方法测定了抗F18^+ETEC IgY对温度、酸碱度、反复冻融、渗透压、胃蛋白酶、胰蛋白酶的稳定性,并考察非还原性糖(乳糖、蔗糖)对IgY活性的影响。结果表明:60℃水浴30min效价无变化;pH4.0~11.0环境中,IgY活性改变不显著;经7次反复冻融和50%蔗糖渗透压处理,抗原结合活性也几乎未受损失;pH2.5时,该IgY对胃蛋白酶非常敏感,经胃蛋白酶37℃处理4h,效价从1:7200下降到1:450;37℃时分别经胃蛋白酶(pH4)和胰蛋白酶(pH7,5)各处理4h,效价均无变化;在胃蛋白酶的处理中,蔗糖和乳糖对该IgY具有一定的保护作用。  相似文献   

4.
用直接结晶法从重组载体注射鸡蛋清中提取重组人溶菌酶(rhLYZ),并对其理化及生物学特性进行了鉴定。结果显示,rhLYZ能被hLYZ特异抗体识别;纯化的rhLYZ和天然hLYZ的热稳定性无显著差异,二者在pH3.0~11.0范围内均具有活性,pH为7.0时活性最强。采用最小抑菌浓度法测定了含rhLYZ蛋清和纯化rhLYZ对12种常见细菌的溶菌活性,二者对除有鞭毛伤寒杆菌和鳖嗜水气单胞菌以外的参试茵均有不同程度的抑制作用。表明,表达在重组栽体注射鸡蛋清中的rhLYZ具有与天然hLYZ十分相似的分子质量、热稳定性、pH活性范围和溶菌谱。  相似文献   

5.
方法:采用甲壳糖和0.25%戊二醛固定脂肪酶,并测定固定化脂肪酶的活性和稳定性;结果:pH在6.5-7.0之间时,固定化脂肪酶活性最高;在40℃时,游离脂肪酶和固定化脂肪酶均表现最高活力,但是固定化脂肪酶活力在30-50℃之间差异不显著,而游离脂肪酶活力在30-50℃之间差异显著。固定化脂肪酶在0.9%NaCl溶液中逐步释放的,前5次回收重复使用固定化脂肪酶,其活力基本变化不大(P〉0.05),结论:甲壳糖和0.25%戊二醛交联作为载体固定脂肪酶最高活性的最适pH和最适温度均比游离脂肪酶的范围大。  相似文献   

6.
针对9种常见肠道致病菌的免疫乳的研究   总被引:11,自引:4,他引:7  
以9株人肠道病原菌(致病大肠杆菌3株、志贺氏菌3株、沙门氏菌3株)制备的混合抗原对孕牛进行系统免疫,以获得对人致病肠道杆菌具有特异性的牛乳抗体。对母牛进行系统免疫后,免疫乳和非免疫乳中IgG总含量没有显著变化。但经免疫处理的母牛,其初乳(产犊后24h内)中针对9种致病肠道杆菌的特异性IgG效价为2^10-2^12,而非免疫母牛为2^7-2^10,免疫处理后初乳中特异性IgG效价提高了2—9倍;经免疫处理的母牛,其常乳中针对9种致病肠道杆菌的特异性IgG效价为2^6-2^10,而非免疫母牛为2^1-2^6,免疫处理后常乳中特异性IgG效价提高了8-14倍。对免疫乳中IgG热致变性进行研究,其结果为:经60℃、10min,60℃、30min,70℃、10min,70℃、30min,80℃、10min,80℃、30min加热处理,免疫乳中IgG变性率分别为14.81%、25.20%、76.44%、85、58%、100%、100%。对免疫乳中IgG酸稳定性进行研究,其结果为:经pH2、10min,pH2、30min,pH4.5、60min,pH4.5、120min处理,免疫乳中IgG活性持留率分别为66.69%、56.55%、100%、100%。  相似文献   

7.
患肠炎病草鱼消化酶活性的研究   总被引:3,自引:0,他引:3  
本文分析了健康鱼和患肠炎病草鱼淀粉酶和蛋白酶活性,其淀粉酶最适pH值均为7.2蛋白酶最适pH值分别为7.0和6.0;其淀粉酶最适温度分别为30℃和35℃,蛋白酶最适温度均为40℃,且患肠炎病草鱼蛋白酶和淀粉酶活性较健康鱼低,但pH值在5.7以下时,患病鱼的蛋白酶活性较健康鱼高,温度在28℃以下时,患病鱼的淀粉酶活性比健康鱼高。  相似文献   

8.
应用卡介苗(BOG)和内毒素(LPS)在鸡体内诱导产生肿瘤坏死因子(TNF),检测TNF在pH值5.5、7.0、8.0和在60℃、65℃、70℃各处理30min,胰蛋白酶处理30min,对L929细胞的杀伤活性。结果表明,鸡TNF在pH7.0时活性最强,其次为pH5.3,pH8.0时活性最弱。60℃、65℃各处理30min活性不受影响,70℃和胰蛋白酶处理30min活性丧失。  相似文献   

9.
以9株人肠道病原茵(大肠杆茵3株、志贺氏茵3株、沙门氏茵3株)制备的混合抗原对孕牛进行系统免疫,以获得对人致病肠道杆茵具有特异性的牛乳抗体。其免疫初乳中针对9种致病肠道杆茵的特异性IgG效价为2^11-2^12,为非免疫初乳的128-256倍;免疫常乳中针对9种致病肠道杆茵的特异性IgG效价为2^6-2^8。为非免疫常乳的16-64倍。动物实验表明,免疫初乳及效价为1:64的免疫常乳对肠产毒性大肠杆茵、鼠伤寒沙门茵、福氏志贺茵所致小鼠腹泻均有保护作用,这是由免疫乳中特异性IgG所决定的。  相似文献   

10.
嗜酸乳杆菌对胃肠道酶的敏感性研究   总被引:3,自引:0,他引:3  
以MRS为培养基,模拟胃肠环境对嗜酸乳酸茵对pH、胃蛋白酶、胰蛋白酶、胆汁盐的敏感性进行了研究。结果表明:在pH1.60~5.00、温度37℃,胃蛋白酶0.592ug/mL-1.4821μg/mL条件下,活茵数能达到108cfu/mL以上。在MRS培养基自然pH条件下,胰蛋白酶活力在14.24u/g-72.32u/g范围内,胆汁盐0.2%的情况下,活茵数能达到107cfu/mL以上。证明了嗜酸乳酸茵能顺利通过胃肠环境,促进人体健康。  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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