鸡蛋中氟喹诺酮类药物残留量检测方法研究

建立一种可同时检测鸡蛋中四种氟喹诺酮类药物(环丙沙星、达氟沙星、恩诺沙星和沙拉沙星)残留的高效液相色谱-荧光检测法。结果表明,四种氟喹诺酮类药物中环丙沙星、恩诺沙星、沙拉沙星在2~500 ng/mL范围内峰面积与浓度呈良好的线性关系,R2均大于0.9999;达氟沙星在0.4~100 ng/mL范围内峰面积与浓度呈良好的线性关系,R2大于0.9999。环丙沙星、恩诺沙星、沙拉沙星的定量限为10μg/kg,达氟沙星的定量限为2μg/kg。环丙沙星、恩诺沙星、沙拉沙星在10~200μg/kg的浓度添加水平上,其回收率为70%~100%;达氟沙星在2~40μg/kg的浓度添加水平上,其回收率为70%~100%,批内、批间的相对标准偏差均小于10%。     

高效液相色谱法测定羊奶中五种氟喹诺酮类药物残留量的研究

建立了一种可同时检测羊奶中五种氟喹诺酮类药物(环丙沙星、达氟沙星、恩诺沙星、沙拉沙星、二氟沙星)残留的高效液相色谱—荧光检测法。羊奶样品经乙腈提取,正己烷去脂肪,C18柱净化。以0.05 mol/L磷酸三乙胺溶液和乙腈溶液为流动相,流速为0.8 m L/min,激发波长280 nm,发射波长450 nm。结果表明环丙沙星、恩诺沙星、沙拉沙星、二氟沙星在10~200 ng/m L,达氟沙星在2~40 ng/m L呈良好的线性关系,R2均大于0.999。环丙沙星、恩诺沙星、沙拉沙星、二氟沙星的最低定量限为30μg/kg,达氟沙星的最低定量限为6μg/kg。环丙沙星、恩诺沙星、沙拉沙星、二氟沙星在30~200μg/kg的浓度添加水平上,达氟沙星在6~40μg/kg的浓度添加水平上其回收率均在70~100%,批内、批间的相对标准偏差小于20%。该方法简单快速、灵敏度高、重复性好,适用于羊奶中五种氟喹诺酮类药物残留检测。     

高效液相色谱荧光检测法测定牛奶中4种氟喹诺酮类药物残留

为了建立一种同时测定牛奶中4种氟喹诺酮类药物(恩诺沙星、环丙沙星、沙拉沙星、二氟沙星)多残留高效液相色谱检测方法,将牛奶中的残留药物用磷酸-甲醇溶液重复提取2次,正己烷除去脂肪净化后浓缩,流动相溶解后用高效液相色谱-荧光检测器测定。结果表明,4种氟喹诺酮类药物在0.01~1.00μg/mL浓度范围内具有良好的线性关系(R=0.999 9),在0.01,0.05,0.10,0.50μg/mL和1.00μg/mL 5个浓度添加水平上,平均回收率为77%~93%,样品的批内和批间变异系数均值分别为5.29%和7.83%,定量限均为10 ng/mL。环丙沙星、恩诺沙星、沙拉沙星检测限均为5 ng/mL,二氟沙星检测限为8 ng/mL。本研究建立的检测方法简单、快速、灵敏度和回收率高,适用于牛奶中4种氟喹诺酮类药物残留检测。     

高效液相色谱法测定鸡蛋中氟喹诺酮类药物残留量前处理方法的优化

建立了鸡蛋中环丙沙星、达氟沙星、恩诺沙星和沙拉沙星4种氟喹诺酮类药物残留测定的超高效液相色谱方法。样品经磷酸盐缓冲液提取后,用正己烷脱脂,C18固相萃取柱净化,反相高效液相色谱分离,荧光检测器测定。本方法的检测限为环丙沙星、恩诺沙星和沙拉沙星5 μg/kg,达氟沙星1 μg/kg。环丙沙星、恩诺沙星和沙拉沙星在2~200 ng/mL、达氟沙星在0.4～40 ng/mL范围内呈线性相关,相关系数r大于0.9999。在空白鸡蛋中添加环丙沙星、恩诺沙星和沙拉沙星5~50 μg/kg、达氟沙星1～10 μg/kg,4种氟喹诺酮类药物的平均回收率为82.2～101.3％,批内变异系数0.8～5.9％之间(n＝6),批间变异系数在1.0～6.6％之间(n＝4)。结果表明,该法灵敏、准确、特异性强,适用于鸡蛋中氟喹诺酮类药物残留的测定。     

高效液相色谱法检测多种动物组织中氟喹诺酮类药物残留量的研究

建立了猪、牛、羊、鸡、兔的肌肉、脂肪、肝脏和肾脏四种组织中环丙沙星、达氟沙星、恩诺沙星、沙拉沙星和二氟沙星残留量检测的高效液相色谱法。试样经磷酸盐溶液提取,C18固相萃取柱浓缩净化后,用高效液相色谱分析,荧光检测器检测,外标法定量。5种药物在0.1～100μg/L浓度范围内线性关系良好。环丙沙星、恩诺沙星、沙拉沙星和二氟沙星在五种动物肌肉、脂肪组织中的定量限为5μg/kg,在肝脏、肾脏组织中的定量限为10μg/kg;达氟沙星在肌肉、脂肪组织中的定量限为1μg/kg,在肝脏、肾脏组织中的定量限为2μg/kg。在指定的三个浓度添加水平下,5种药物在各组织中的平均回收率为62%～103%;批内变异系数为0.30%～18%,批间变异系数为1.0%～17%。该方法操作简单,准确度和精密度好,动物品种及动物组织覆盖范围广,可以很好地满足实际检测工作的需要。     

牛奶中七种氟喹诺酮类药物残留检测高效液相色谱-串联质谱法研究

建立了牛奶中氧氟沙星、诺氟沙星、环丙沙星、恩诺沙星、达氟沙星、二氟沙星和沙拉沙星等七种氟喹诺酮类药物(FQs)残留检测的高效液相色谱-串联质谱(HPLC-MS/MS)方法。液相色谱条件为:色谱柱Waters XBridge C18柱(150 mm×2.1 mm,5μm);流动相为0.1%甲酸甲醇溶液 0.1%甲酸水溶液,梯度洗脱;柱温为35℃;流速为0.2 mL/min;进样量为20μL。质谱条件为:电喷雾离子源(ESI ),多反应监测(MRM)方式进行采集;外标法定量。结果表明:七种FQs在5~250 ng/mL浓度范围内呈现良好的线性关系,相关系数R2均大于0.997;方法检测限为2 ng/mL,定量限为5 ng/mL;从10、20和100 ng/mL三个添加浓度检测结果可以看出,方法平均回收率为70.2%~119%,批内RSD为1.8%~16%,批间RSD为9.1%~18%。     

猪肉组织中7种氟喹诺酮类药物残留检测高效液相色谱-串联质谱法研究

建立了猪肉组织中氧氟沙星、诺氟沙星、环丙沙星、恩诺沙星、达氟沙星、二氟沙星和沙拉沙星7种氟喹诺酮类药物残留检测的高效液相色谱-串联质谱方法。液相色谱条件为：色谱柱为XBridge C18柱（150×2.1mm,5µm）;流动相为0.1％甲酸甲醇溶液＋0.1％甲酸水溶液,梯度洗脱;柱温为30℃;流速为0.2mL/min;进样量为20µL。质谱条件为：电喷雾离子源（ESI＋）,多反应监测（MRM）方式采集。以诺氟沙星-D5作内标,内标法定量。结果表明：7种FQs药物在5～250ng/mL浓度范围内呈现良好线性关系,相关系数R2均大于0.997;方法检测限为5ng/g,定量限为10ng/g;从10、20和100ng/g三个添加浓度检测结果可以看出,方法平均回收率为80.7%～116%（n＝6）,批内批间RSD均小于20％。     

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。     

高效液相色谱法检测猪肉中4种氟喹诺酮类药物残留方法的优化

试验为建立1种采用高效液相色谱法检测猪肉组织中环丙沙星(CIP)、达氟沙星(DFLX)、恩诺沙星(ENR)、沙拉沙星(SAR)残留量的方法。按照农业农村部标准方法进行优化,猪肉样品经磷酸盐溶液提取,固相萃取柱浓缩净化,使用高效液相色谱分析,荧光检测器检测,外标法定量。结果表明:环丙沙星、恩诺沙星、沙拉沙星在5～500μg/L浓度范围内,达氟沙星在1～100μg/L线性关系良好。猪肉中环丙沙星、恩诺沙星、沙拉沙星检出限为5μg/L,达氟沙星检出限为1μg/L。在指定的高、中、低3个浓度添加水平下,4种药物在猪肉的回收率为66.1%～107.9%;批内变异系数为1.3%～6.4%,批间变异系数为2.8%～7.1%。研究表明,该方法操作简单、准确度和精密度较好、实用性强、灵敏度高,可以满足猪肉样品中氟喹诺酮类4种药物残留检测的需要。     

沙拉沙星、二氟沙星直接竞争化学发光酶联免疫检测方法的建立

为快速检测食源性动物中沙拉沙星及二氟沙星的药物残留,将沙拉沙星单克隆抗体(SAR-Ab)与辣根过氧化物酶(HRP)偶联得到酶标抗体(McAb-HRP),从而建立直接竞争化学发光酶联免疫(dc-CLEIA)检测方法。结果显示:经紫外扫描鉴定,McAb-HRP偶联成功;以包被抗原(SAR-1-OVA)浓度1.25μg/mL,McAb-HRP稀释比1∶8 000作为最佳工作条件,从而建立了dc-CLEIA分析法;精密度的平均批内批间变异系数均低于7%;建立的标准曲线呈线性关系,线性范围为0.312～20 ng/mL,回归方程式y=-0.373x+0.688(R~2=0.985),经计算其灵敏度IC_(50)为3.19 ng/mL;除二氟沙星外与其他氟喹诺酮类药物的交叉反应率均低于8%,与其他种类的抗生素均无交叉反应;沙拉沙星和二氟沙星在鸡肉样品中的最低检出限分别为1.25、1.36μg/kg;沙拉沙星和二氟沙星在鸡肉样品中的添加回收率分别为88.2%～108.3%、93.36%～102.7%,且其变异系数均≤13.4%。结果表明:此方法不仅快速且灵敏度高,可作为沙拉沙星及二氟沙星药物残留的定量检测方法。     

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.