不同精油的抑菌效果及协同作用研究

为研究三种精油(肉桂醛、百里香酚、香兰素)的抑菌效果及其协同作用,本试验采用牛津杯法和试管二倍稀释法测定抑菌圈的值径及最小抑菌浓度,结果表明:三种精油对大肠杆菌K88、沙门氏菌、金黄色葡萄球菌都有较强的抑菌效果,在相同浓度下,抑菌效果为肉桂醛>百里香酚>香兰素;当百里香酚与肉桂醛以4∶1复合时,对大肠杆菌K88的抑菌效果最佳;当肉桂醛与香兰素以4∶1复合时,对沙门氏菌和金黄色葡萄球菌的抑菌效果最佳。综上所述,肉桂醛和百里香酚的抑菌效果优于香兰素,百里香酚与香兰素,肉桂醛和香兰素复配时具有协同作用。     

黄颡鱼源嗜水气单胞菌对氟苯尼考的耐药性及其消失速率研究

在离体条件下通过测定最小抑菌浓度MIC值,研究4株黄颡鱼源嗜水气单胞菌对氟苯尼考的耐药产生速率与耐药性消失速率。结果表明:以37℃条件下培养48h为1代,HSY02菌株对氟苯尼考的最小抑菌浓度为3.906 3μg/m L,HSY01、HSY03、HSY04菌株对氟苯尼考的最小抑菌浓度为1.953 1μg/m L。在含有氟苯尼考的药物营养肉汤培养基中连续传代8代后,氟苯尼考对3株嗜水气单胞菌HSY01、HSY03、HSY04的最小抑菌浓度(MIC)由1.953 1μg/m L上升至62.50μg/m L,耐药性增长了32倍。HSY02菌株的最小抑菌浓度(MIC)由3.906 3μg/m L上升至62.50μg/m L,耐药性增长了16倍;且耐药性获得后保持稳定,其消失速率为0。     

载铜、载银蒙脱石抗菌性能研究

将两种高纯蒙脱石和Cu(NO3)2、AgNO3在适宜反应条件下分别制备成载铜、载银蒙脱石,采用离子选择电极法分别测定载铜、载银蒙脱石中的Cu2+、Ag+含量,计算吸附量;对载铜、载银蒙脱石进行X射线衍射(XRD)检测其晶体结构;采用抑菌圈直径、最小抑菌浓度(MIC)和最小杀菌浓度(MBC)法测定载铜、载银蒙脱石的抗菌性能。结果表明,载铜、载银蒙脱石晶体结构与原料蒙脱石结构一致。两种载银蒙脱石对大肠杆菌和金黄色葡萄球菌的抑菌圈直径比两种载铜蒙脱石的大。两种载银蒙脱石对大肠杆菌、金黄色葡萄球菌的最小抑菌浓度、最小杀菌浓度均低于两种载铜蒙脱石。结果提示,载铜、载银蒙脱石对大肠杆菌和金黄色葡萄球菌具有较强的抗菌性能,载银蒙脱石的抗菌效果优于载铜蒙脱石。     

氟苯尼考与甲氧苄啶复方注射液的抑菌性试验

对氟苯尼考与甲氧苄啶配伍来制备复方注射剂的有效性,进行了配伍增效的抑菌效果研究。采用体外抑菌效果试验,利用临床分离的5株猪大肠杆菌为试验菌株,进行了氟苯尼考与甲氧苄啶联用的体外抑菌效果试验,以及比较复方氟苯尼考与氟苯尼考的MIC值。测得氟苯尼考、甲氧苄啶的最小抑菌浓度(MIC)分别为8μg/m L和16μg/m L,两药联合应用的部分抑菌浓度指数(FIC)值介于0.375~0.75之间,呈现协同或相加作用,其中氟苯尼考与甲氧苄啶按照5∶1的比例联合应用时的MIC值最小,抗菌效果最好。复方氟苯尼考的抑菌效果明显高于氟苯尼考,比氟苯尼考的抑菌效果增加了4~8倍。说明氟苯尼考与甲氧苄啶配伍制备复方注射液具有实际应用价值,并提供了复方配比的参考比例。     

5种中药对大肠杆菌的抑菌作用

为研究黄连、黄芩、五倍子、黄柏和鱼腥草提取物对大肠杆菌的抑菌效果,采用超声波处理,乙醇回流,水浴加热的方法提取5种中药的有效成分,采用二倍稀释法分别测定提取物对大肠杆菌的最小抑菌浓度(Minimum inhibitory concentration,MIC)和最小杀菌浓度(Minimum bactericidal concentration,MBC),采用肉汤稀释棋盘法,测定提取物对大肠杆菌的联合抑菌效果。结果显示,鱼腥草和五倍子单独抑菌时的MIC值较其他中药的MIC值低,且鱼腥草与黄芩和五倍子联合用药时MIC值由15.63 mg/m L降到3.91 mg/m L,同时五倍子与黄芩和鱼腥草联合用药时MIC值也由15.63 mg/m L降到3.91 mg/m L。黄芩与黄连、黄柏、五倍子、鱼腥草联合用药时MIC值均降低。结果表明:鱼腥草、黄芩、五倍子对大肠杆菌有较好的抑菌作用,鱼腥草、黄芩、五倍子联用时,抑菌效果为协同或相加作用;黄连与其他4种中药联用时抑菌效果为无关作用;黄柏与黄芩、五倍子及鱼腥草联用时抑菌效果为无关作用。     

艾叶水提液对3种细菌的体外抑菌试验

为了观察艾叶水提液对金黄色葡萄球菌、大肠杆菌和乙型伤寒沙门氏菌的体外抑菌效果,试验采用二分法和牛津杯法分别测定艾叶水提液的最小抑菌浓度(MIC)和抑菌效果。结果表明:艾叶提取液浓度为2,1,0.5和0.25 g∕m L时,金黄色葡萄球菌与大肠杆菌和乙型伤寒沙门氏菌的抑菌效果差异显著(P0.05);在浓度为2,1 g∕m L时,提取液对金黄色葡萄球菌表现为高敏,对大肠杆菌和乙型伤寒沙门氏菌均表现为中敏;3种细菌的MIC均为0.125 g∕m L。说明艾叶水提液对3种菌均有抑制和杀灭作用,对金黄色葡萄球菌的抑菌效果略优于大肠杆菌和乙型伤寒沙门氏菌。     

8种中草药对常见水产病原菌的抑制作用

为解决水产养殖业中细菌性疾病及抗生素滥用问题,研究了中草药对几种水产病原菌的抑菌效果。以嗜水气单胞菌、海豚链球菌等8种常见水产病原菌为研究对象,选用黄芩、冬青等8种中草药,测定其水提物及醇提物对上述8种菌的最小抑菌浓度(MIC),并将结果与6-间甲氧磺胺嘧啶、头孢哌酮等11种抗生素的抑菌效果进行比较。结果表明:在所测试的细菌中,黄芩、冬青、生姜的MIC达到4 mg/m L,厚朴、艾叶、两面针的MIC达到10 mg/m L,黄柏、栀子的MIC达到20 mg/m L,而抗生素的MIC达到0. 1μg/m L。总体而言,黄芩、冬青的抑菌效果较好,中草药醇提物的抑菌效果优于水提物,而抗生素的抑菌效果优于中草药提取物。     

多种饲料添加剂类抗生素对猪源产气荚膜梭菌的抑菌效果研究

本试验目的在于研究多种不同饲料添加剂类抗生素对产气荚膜梭菌的抑菌试验,筛选出对产气荚膜梭菌抑菌效果强的药物,为饲料、养殖业临床上控制产气荚膜梭菌提供理论依据。试验选用喹乙醇、4%恩拉霉素、盐霉素、硫酸黏霉素、15%杆菌肽锌、黄霉素、吉他霉素和盐酸金霉素八种饲料常用抗生素添加剂,采用试管稀释法对猪源产气荚膜梭菌野毒株进行抑菌试验。试验结果表明:(1)恩拉霉素抑菌作用最强,其MIC为1.6μg/m L;(2)喹乙醇和15%杆菌肽锌抑菌作用较强,它们的MIC分别为4μg/m L和6μg/m L;(3)黄霉素、硫酸黏霉素、吉他霉素抑菌作用较弱,它们的MIC分别为40μg/m L、200μg/m L、300μg/m L;(4)盐霉素及盐酸金霉素对该产气荚膜梭菌野毒株几乎没有抑菌作用。由以上八种抗生素对产气荚膜梭菌的抑菌试验结果得出,八种抗生素对该产气荚膜梭菌野毒株均有不同程度的抑菌作用,而恩拉霉素对产气荚膜梭菌抑菌效果最强。     

蒙脱石对黄曲霉毒素B_1（AFB_1）和玉米赤霉烯酮（ZEN）的体外吸附效果

旨在比较蒙脱石对黄曲霉毒素B_1（AFB_1）和玉米赤霉烯酮（ZEN）的体外吸附效果。分别在pH值3.0和pH值6.5的条件下,采用ELISA方法评价蒙脱石对AFB1和ZEN的体外吸附效果。结果表明,pH值3.0条件下,蒙脱石对AFB_1的吸附率和吸附量分别为88.00%、440.00μg/g,对ZEN的吸附率和吸附量分别为7.50%、37.50μg/g;pH值6.5条件下,蒙脱石对AFB_1的吸附率和吸附量分别为84.00%、420.00μg/g,对ZEN的吸附率和吸附量分别为6.60%、33.00μg/g。综上提示,蒙脱石对AFB_1的吸附效果较好,对ZEN的吸附效果较差。     

苹果树腐烂病高效杀菌剂的筛选

以抑菌率为指标,测定了22种药剂对苹果树腐烂病的抑菌效果,从而筛选出各药剂的最佳浓度,并利用聚类分析选出最佳药剂。结果表明:试验所选用的22种供试药剂,多粘类芽孢杆菌、枯草芽孢杆菌浓度为18μL/(100mL)时抑菌效果达到100%;多抗霉素、丙环唑、戊唑醇、咪鲜胺、苯醚甲环唑的浓度分别为22.5mg/(100mL)、60μL/(100mL)、75μL/(100mL)、75μL/(100mL)、60mg/(100mL)时,抑菌效果达到100%。枯草芽孢杆菌、多粘类芽孢杆菌、多抗霉素、苯醚甲环唑、丙环唑、戊唑醇、咪鲜胺、苯丙·甲环唑抑菌效果最好     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

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。     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

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.     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

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.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

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.     

The Prevalence and Intensity of Helminth and Coccidial Infections in Dairy Cattle in Central Kenya

A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.     

A brief history of the prevention of infectious diseases by immunisations

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.     

Micronutrient Content of Certain Tropical Conventional and Unconventional Feed Resources of Southern India

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.     

Bovine Mastitis in Selected Areas of Southern Ethiopia

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.     

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

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。