鸡肝组织中磺胺类药物多残留分析法

建立了鸡肝组织中磺胺嘧啶、磺胺二甲基嘧啶、磺胺甲氧吡嗪、磺胺－6－甲氧嘧啶、磺胺甲恶唑、磺胺－2，6－二甲氧嘧啶和磺胺喹恶啉的多残留高效液相色谱分析法。样品经乙腈提取、正己烷液－液分配和碱性氧化铝柱固相萃取法净化后用反相高效液相色谱法测定（UV270nm）。7种磺胺类药物标准曲线的相关系数（r^2)为0．9991－1．0000（0.01μg/ml-0.5μg/ml）。在0.05mg/kg-0.5mg/kg浓度范围内，磺胺类药物的回收率为68．8％－100．0％，变异系数为1．3％－12．0％。 检测限为0．01mg/kg-0.03mg/kg，定量限低于0.05mg/kg。     

鸡血浆中磺胺氯吡嗪钠和甲氧苄啶含量HPLC检测方法的建立

建立了鸡血浆中磺胺氯吡嗪钠和甲氧苄啶含量测定的HPLC方法。对鸡血浆中磺胺氯吡嗪和甲氧苄啶采用乙腈提取和净化,梯度洗脱,高效液相色谱紫外检测法测定,外标法定量。流动相为甲醇-0.02 mol/L磷酸二氢钾水溶液。紫外测定时采用双波长检测:磺胺氯吡嗪检测波长为268 nm,甲氧苄啶检测波长为240 nm。空白血浆添加磺胺氯吡嗪和甲氧苄啶分别在0.1～70.0μg/m L和0.05～5.00μg/m L范围内线性关系良好(R~2均大于0.9999),磺胺氯吡嗪和甲氧苄啶的检测限分别为0.05μg/m L和0.025μg/m L,定量限分别为0.1μg/m L和0.05μg/m L。空白血浆添加磺胺氯吡嗪和甲氧苄啶在各自线性范围内,批内变异系数分别小于6.84%和7.55%,批间系数分别小于5.23%和6.81%。本研究建立的鸡血浆中磺胺氯吡嗪和甲氧苄啶的提取和净化方法,适用于鸡血浆中磺胺氯吡嗪和甲氧苄啶含量的单个或同时测定。     

高效液相色谱法测定鸡蛋中氯霉素残留量

采用高效液相色谱法(HPLC)检测鸡蛋中氯霉素的残留量。鸡蛋(全蛋)试样中残留的氯霉素用乙酸乙酯提取,35℃减压蒸干。残渣用正己烷-氯仿(1 1,V/V)溶解,加少量水,混匀后,离心,取上清液作为试样溶液供高效液相色谱仪(紫外检测器)在280nm处测定,外标法定量。本方法在鸡蛋中检出限为2μg/kg,回收率在60％～90％,批内变异系数小于12.0％,批间变异系数小于15.0％。     

超高效液相色谱-串联质谱法同时检测鸡蛋中5种磺胺类药物和甲氧苄啶残留量

建立超高效液相色谱-串联质谱法(Ultrahigh-performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)同时测定鸡蛋中5种磺胺类药物(磺胺甲恶唑、磺胺二甲嘧啶、磺胺间甲氧嘧啶、磺胺喹噁啉、磺胺二甲氧嘧啶)和甲氧苄啶的残留量的方法。样品经乙腈提取2次, 95%乙腈溶液进行溶解后,过Alumina B Cartridges柱,30%乙腈洗脱,滤膜过滤后滤液用于超高效液相色谱-串联质谱仪测定,外标基质标准曲线法定量。在0.5～100μg/kg的浓度范围内5种磺胺类药物和甲氧苄啶色谱峰面积与浓度呈良好线性相关,相关系数均大于0.99;方法检测限0.5μg/kg、定量限为1.0μg/kg;鸡蛋样品中5种磺胺类药物和甲氧苄啶在1.0～100.0μg/kg添加水平内的平均回收率在66.3%～97.5%之间,批内、批间相对标准偏差在1.4%～11.4%之间。该方法回收率满足残留检测要求,且方法的重现性良好,满足国内外兽药残留相关法规规定。     

牛奶中氯唑西林残留量的高效液相色谱法测定

为建立高效液相色谱法测定牛奶中氯唑西林残留的方法,牛奶样品用乙腈沉淀蛋白,三氯甲烷反萃取,有机相旋干用流动相溶解,正己烷除脂。0.02mol/L磷酸二氢钾溶液(pH 5.0)-乙腈(68∶32)比例为流动相,C18反相色谱柱分离,紫外检测。结果氯唑西林在15μg/kg～1 000μg/kg范围内呈现良好的线性关系,相关系数大于0.999 0;在15、30、60μg/kg三个添加水平,氯唑西林在牛奶中的平均回收率为70.25%～94.38%,批内变异系数小于8.34%,批间变异系数小于3.52%。方法检出限为5μg/kg,定量限为15μg/kg。表明该检测方法简单、灵敏、可靠,适用于牛奶中氯唑西林残留的分析检测。     

酶联免疫吸附法测定猪尿中安定的残留

用酶联免疫吸附法对猪尿中残留的安定进行检测，结果得出该方法的最低检出限为5．0μg/L；回收率在60％以上，批内变异系数≤17％，批问变异系数小于≤14％。表明该方法可用于安定残留量的筛选检测。     

鸡皮脂和肾脏中替米考星残留HPLC检测方法的建立

本试验旨在建立鸡皮脂和肾脏组织中替米考星残留量的HPLC测定方法。皮脂和肾脏组织中残留的替米考星用乙腈提取、MCX固相萃取柱净化,采用高效液相色谱-紫外检测法测定。皮脂组织和肾脏组织中替米考星检测限分别为20μg/kg和30μg/kg,定量限分别为35μg/kg和50μg/kg。空白皮脂组织添加替米考星在35～150μg/kg浓度水平,回收率在75%～98%之间,批内与批间变异系数均小于10%;空白肾脏组织添加替米考星在50～500μg/kg浓度水平,回收率在71%～97%之间,批内变异系数小于11%,批间变异系数小于10%。本试验建立的方法快速、准确、灵敏,适用于鸡皮脂和肾脏组织中替米考星残留量的检测。     

直接竞争ELISA检测氯霉素残留的方法建立及初步应用

用混合酸酐法合成氯霉素的CAP抗原,用过碘酸钠氧化法合成CAP酶标记抗原,用ELISA方法对合成的CAP抗原、CAP酶标记抗原进行鉴定表明其与抗CAP单克隆抗体具有特异性反应。在此基础上建立了包被二抗的直接竞争ELISA方法。特异性试验结果表明,CAP琥珀酸酯、CAP琥珀酸钠盐的交叉反应率分别为107%、106.4%;甲砜霉素、氟甲砜霉素与CAP的交叉反应率小于0.016%;与其他结构类似物间未见交叉反应。该方法对CAP的检测限可达到0.1μg/L,IC50为11.6μg/L,线性范围0.1～100μg/L,批内变异系数小于11.5%,批间变异系数小于19.6%。对猪肉、鸡肉、蜂蜜分别添加1.0、3.0、10.0、30.0μg/L CAP标准品,回收率61.0%～102.0%,变异系数为6.6%～15.8%;对猪肉、鸡肉、蜂蜜中CAP的最低检测限分别为0.48、0.42、1.20μg/kg。     

ELISA法测定牛奶和鸡肌肉中四环素类药物残留

以本实验室研制的四环素类药物多残留检测试剂盒为基础，建立了牛奶和鸡肉中四环素、土霉素、金霉素药和多西环素的ELISA检测方法。该方法对牛奶和鸡肉中四环素的检测限为7μg／L（μg／kg）左右。在牛奶和鸡肉中，4种四环素类药物100μg／L（μg／kg）浓度的添加回收率范围为43．6％～101．4％，批内变异系数小于25％，批间变异系数在30％以内。牛奶的临界值为39．5μg／L，鸡肉的临界值为35.3μg／kg。     

牛可食性组织中加米霉素残留量的液相色谱-串联质谱检测方法的研究

本试验建立了牛可食性组织中加米霉素残留量检测的制样和高效液相色谱-串联质谱检测方法,适用于牛组织中加米霉素残留量的测定。牛组织(牛的肌肉、肝脏、肾脏和脂肪)经绞碎、均质后,样品经0. 1 mol/L磷酸二氢钾缓冲液提取,Oasis HLB固相萃取柱净化,高效液相色谱-串联质谱法检测,内标法定量。该方法特异性好,空白样品无干扰。该方法的检测限为1μg/kg,定量限为2μg/kg,基质匹配标准曲线范围为5μg/L～500μg/L,相关系数 0. 99;牛肌肉和肾脏组织在2、50、100、200μg/kg四个添加浓度的平均回收率为93. 56%～103. 31%,批内变异系数≤8. 67%,批间变异系数≤6. 70%;牛肝脏组织在2、100、200、400μg/kg四个添加浓度的平均回收率为94. 37%～102. 52%,批内变异系数≤5. 70%,批间变异系数≤4. 61%;牛脂肪组织在2、10、20、40μg/kg四个添加浓度的平均回收率为100. 95%～105. 58%,批内变异系数≤5. 89%,批间变异系数≤4. 52%。     

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。     

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.     

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.     

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.     

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。     

Microsporidial keratopathy in two dogs

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.