超高效液相色谱-串联质谱法测定鸡蛋中四环素类、喹诺酮类、磺胺类残留量

建立了超高效液相色谱-串联质谱法，测定了鸡蛋中四环素类、喹诺酮类、磺胺类11种抗生素残留量。采用1%酸化乙腈溶液提取，应用超高效液相色谱-串联质谱仪检测，定量方法采用外标法。鸡蛋中上述11种药物在5～100ng/mL的浓度范围内呈现良好的线性关系，鸡蛋中的检测限为1.0μg/kg，定量限为2.0μg/kg，在1.0～50μg/kg添加浓度范围内的回收率为70.2%～90.2%，批内与批间RSD值均<7.9%。     

液相色谱串联质谱法测定饲料中孔雀石绿和结晶紫及其代谢物

建立液相色谱-质谱/质谱法测定饲料中孔雀石绿和结晶紫及其代谢物的检测方法,旨在提高检测效率和检测低限。实验中采取乙腈提取待测物,样品经过中性氧化铝柱净化后进行液相色谱-串联质谱仪分析。结果表明孔雀石绿和结晶紫及其代谢物标准品在3个添加浓度0.5、1.0、4.0μg/kg的平均回收率为93.5%～117.8%,相对标准偏差为3.3%,测定低限为0.5μg/kg。标准曲线在线性范围0.5～8.0μg/kg内的相关系数0.995。本方法适用于饲料中孔雀石绿和结晶紫及其代谢物的测定。     

超高效液相色谱-串联质谱法测定猪牛组织中甲基盐霉素残留量

建立超高效液相色谱-串联质谱法测定猪牛组织中甲基盐霉素残留量。猪、牛组织中残留的甲基盐霉素,经乙腈溶液提取,硅胶固相萃取柱净化,超高效液相色谱-串联质谱法测定,外标法定量。甲基盐霉素在5 ng/mL～250 ng/mL的浓度范围内呈现良好的线性关系,甲基盐霉素在猪、牛肌肉、肝脏、肾脏、脂肪中的检测限均为2.5μg/kg,定量限均为5.0μg/kg,猪牛肌肉、肝脏、肾脏、脂肪中5.0 ng/g～100 ng/g添加浓度范围内的回收率均值为71.9%～88.4%,批内批间RSD值均<15%。     

超高效液相色谱-串联质谱法测定鸡组织中氯苯胍残留

研究建立了鸡组织中氯苯胍残留的超高效液相色谱-串联质谱检测方法。样品经酸化乙腈提取后,分别经中性氧化铝柱和HLB固相萃取柱净化,C₁₈柱分离,超高效液相色谱-串联质谱测定,外标法定量。氯苯胍在10 ng/mL～500 ng/mL的浓度范围内呈线性相关,相关系数为0.994以上。本方法对氯苯胍在鸡组织中的检测限为5μg/kg,定量限为10μg/kg;鸡肉、鸡肝和鸡肾在添加50μg/kg～200μg/kg浓度范围内,其回收率为76.7%～107.6%,鸡脂肪和鸡皮在添加100μg/kg～400μg/kg浓度范围内, 其回收率为81.2%～106.8%, 批内变异系数均在1.4%～19.5%之间,批间变异系数在2.5%～12.8%之间。本方法快速、灵敏、重现性好,各项技术指标均满足国内外相关法规要求,适用于鸡组织中氯苯胍的残留检测。     

超高效液相色谱-串联质谱法测定鸡组织中泰乐菌素的残留量

建立了鸡组织中泰乐菌素残留的超高效液相色谱-串联质谱法检测方法,样品用甲醇(含2%氨水)提取,经C18固相萃取柱净化,洗脱液氮气吹干,残渣用甲醇:乙腈(20∶80,V/V)复溶,超高效液相色谱-串联质谱法检测,基质添加标准溶液外标法定量。结果表明泰乐菌素在5~1000μg/kg的浓度范围内呈现良好的线性关系。在鸡组织中中泰乐菌素的检测限为4μg/kg,定量限为10μg/kg。在10~200μg/kg添加浓度范围内,泰乐菌素在鸡组织中的回收率均在85.9%~110.4%之间,批内批间变异系数在1.2%~4.0%之间。该方法各项技术指标均能满足残留检测要求,且方法的重现性良好,满足国内外兽药残留相关法规规定。     

高效液相-串联质谱法同时检测鸡蛋中金刚烷胺与四种氟喹诺酮类药物残留的研究

试验建立了可同时测定鸡蛋中金刚烷胺、环丙沙星、恩诺沙星、达氟沙星和沙拉沙星残留量的高效液相-串联质谱法(HPLC-MS/MS)。样品经1%甲酸乙腈提取、氮吹浓缩、复溶、正己烷脱脂净化等步骤处理后,用HPLC-MS/MS检测。结果表明:5种药物在1~50μg/L浓度范围内具有良好的线性关系,空白样品同时添加5种药物的回收率均在76.6%~102.1%之间;定量限为1μg/kg,检出限为0.5μg/kg。该方法操作简单、快速、灵敏、高效。     

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。     

新型反相固相萃取吸附剂测定鸡蛋中4种氟喹诺酮类药物残留量

建立了一种使用新型反相固相萃取吸附剂(PRiME HLB)的前处理净化流程,采用高效液相色谱-荧光检测器同时测定鸡蛋中环丙沙星、达氟沙星、恩诺沙星和沙拉沙星残留量的方法。试样经乙腈∶0.2%甲酸水溶液(80∶20)提取,PRiME HLB固相萃取柱净化后进行测定,外标法定量。实验结果表明:(1)在鸡蛋中环丙沙星、恩诺沙星和沙拉沙星的检测限为0.75μg/kg,达氟沙星的检测限为0.15μg/kg;在0.005~0.5μg/mL质量浓度范围(达氟沙星在0.001~0.2μg/mL浓度范围)内线性回归关系良好(r0.99999)。(2)环丙沙星、恩诺沙星和沙拉沙星的添加量为0.005、0.05、0.5μg/mL(达氟沙星0.001、0.02、0.2μg/mL)时,方法的添加回收率在74.24%~98.78%,RSD5.15%。本方法适用于鸡蛋中4种氟喹诺酮类药物残留量的测定。     

液相色谱-串联质谱法测定饲料中孔雀石绿及其代谢物残留量

建立了液相色谱-串联质谱法同时测定饲料中孔雀石绿及其代谢物隐性孔雀石绿含量的方法。采用乙腈提取试样中的药物,经中性氧化铝柱和阳离子交换柱净化后,进行液相色谱-串联质谱法测定,分别以D5-孔雀石绿和D6-隐性孔雀石绿为内标进行定量分析。孔雀石绿和隐性孔雀石绿的检测限(LOD)均为0.5μg/kg,定量限(LOQ)均为1.0μg/kg,在0.25～40.0μg/l的范围内,线性相关系数r均在0.999以上,加标浓度在1.0～100μg/kg范围内,回收率在79.2%～117.0%之间,相对标准偏差≤7.7%。本方法可快速测定饲料中孔雀石绿和隐性孔雀石绿的含量,操作简单,灵敏度高,结果准确性高,能满足日常检测需要。     

液相色谱-串联质谱法检测牛奶中林可胺类与大环内酯类药物

牛奶食品中林可胺类药物残留可引起肾功能障碍和革兰氏阳性菌的耐药性增加;大环内酯类药物残留可引起过敏反应和导致携带耐药因子的菌株扩散。本试验利用液相色谱-串联质谱法检测牛奶中林可胺类与大环内酯类药物残留。牛奶样品中的残留药物用乙腈提取后,用正己烷去除脂肪等杂质,浓缩后供液相色谱-串联质谱法测定。经试验:系列浓度范围内呈现良好的线性关系,相关系数(R2)均大于0.990,方法的回收率为70%~120%,批内、批间相对标准偏差均小于20%。检测限为1μg/kg,定量限为2.5μg/kg。     

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.     

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.     

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.     

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.