高效液相色谱－串联质谱法检测猪肝组织中氯霉素残留的研究

建立了猪肝组织中氯霉素残留检测的高效液相色谱-串联质谱(LC-MS/MS)法.液相色谱条件为色谱柱为Alltech Altima C18柱(150 mm×3.2 mm,5 μm);流动相为甲醇-水(1∶ 1,V/V);柱温为30 ℃;流速为0.3 mL/min;进样量为20 μL.质谱条件为电喷雾离子源(ESI-),多反应离子监测(MRM)方式进行采集;监测离子质荷比为320.60＞52.20,320.60＞194.15.以氯霉素的同分异构体间位氯霉素作内标,内标法定量.结果表明,氯霉素的线性范围为0.5～10 ng/mL,相关系数R2＝0.999 9;方法检测限为0.1 μg/kg,定量限为0.2 μg/kg;从0.1、0.2、0.4和1.0 μg/kg四个添加浓度检测结果可以看出,方法的平均回收率为96.6%～116.6%(n＝6),批内批间RSD均小于20%.     

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%。     

高效液相色谱-串联质谱法检测猪尿中四种β-受体激动剂残留的研究

建立了猪尿中克仑特罗、莱克多巴胺、沙丁胺醇和西马特罗残留检测的高效液相色谱-串联质谱方法(HPLC-MS/MS).液相色谱条件为色谱柱为XBridge C18柱(150 mm×2.1 mm,5 μm);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0.2 mL/min;进样量为20 μL.质谱条件为电喷雾离子源(ESI ),多反应监测(MRM)方式进行采集;同位素内标法定量.结果表明,四种β-受体激动剂在1～50 ng/mL浓度范围内呈现良好的线性关系,相关指数R2均大于0.998;方法检测限为0.3 ng/mL,定量限为0.5 ng/mL;从0.5、1和2 ng/mL 3个添加浓度检测结果可以看出,方法平均回收率为86.6%～110%,批内RSD为1.1%～8.4%,批间RSD为2.0%～6.2%.     

猪肉组织中四环素类药物残留检测——高效液相色谱-串联质谱法研究

建立了猪肉组织中四环素类药物残留检测的高效液相色谱-串联质谱方法.色谱条件为色谱柱为XBridge C18柱(150 mm×2.1 mm,5 μm),流动相为0.3%甲酸乙腈溶液 0.3%甲酸水溶液;柱温 20 ℃,流速0.2 mL/min;进样量20 μL.质谱条件为电喷雾离子源(ESI );多反应监测(MRM)方式采集.外标法定量.结果表明,四环素、土霉素和金霉素在10～400 ng/mL浓度范围内呈现良好线性,相关指数R2均大于0.999;方法检测限为5 ng/g,定量限为10 ng/g.50、100和200 ng/g三个添加浓度的平均回收率为72.3%～94.6%,批内批间RSD均小于20%.     

HPLC对妥曲珠利纳米乳中有效成分含量的检测

建立高效液相色谱法测定妥曲珠利纳米乳中妥曲珠利含量的方法。色谱柱为Agilent C18(4.6mm×150mm,5μm);流动相为磷酸二氢钾缓冲液(pH3):乙腈(45:55),流速1mL/min,紫外检测波长240nm,柱温30℃,进样量20μL。结果表明,妥曲珠利含量在0.0625μg/mL～100μg/mL范围内与峰面积呈良好的线性关系,检测限为5ng/mL,定量限为15ng/mL,平均加样回收率为99.73%。试验表明,该方法简便灵敏,结果准确可靠,可用于妥曲珠利纳米乳中妥曲珠利的质量控制。     

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％。     

液相色谱-三重四极杆/线性离子阱复合质谱技术检测牛可食性组织中吡利霉素的残留

建立了一种可准确定性定量检测4种牛可食性组织中吡利霉素残留的液相色谱-三重四极杆/线性离子阱(LC-Q-trap MS)复合质谱分析技术。牛肌肉、脂肪、肾脏和肝脏样品经5%甲酸乙腈提取,captiva EMR-Lipid柱净化。以0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相,经Kinetex F5色谱柱分离后,用多反应监测联合信息依赖性采集与增强子离子扫描(MRM-IDA-EPI)模式检测,基质匹配标准溶液校正,外标法定量。结果表明:吡利霉素于牛肌肉和脂肪中在1～100 ng/mL的浓度范围内,于牛肾脏和肝脏中在1～400 ng/mL浓度范围内均呈现良好的线性关系,相关系数(R~2)均大于0.990;在4种空白组织中吡利霉素的检测限均为5μg/kg,定量限均为10μg/kg。吡利霉素在牛肌肉和牛脂肪10～200μg/kg、牛肾脏10～800μg/kg,以及牛肝脏10～2000μg/kg添加浓度范围内的回收率范围在60.2%～101%之间;批内与批间相对标准偏差均小于13%。该方法具有简便快速、灵敏度高、定性准确,重复性好等特点,可以满足上述组织中吡利霉素残留检测的要求。     

鸡蛋和鸡肉中尼卡巴嗪残留检测高效液相色谱 串联质谱法研究

建立了鸡蛋和鸡肉中尼卡巴嗪残留标示物4,4'-二硝基碳酰替苯胺(DNC)检测的高效液相色谱-串联质谱方法(HPLC-MS/MS).液相色谱条件为色谱柱为XBridge C18柱(150 mm×2.1 mm,5 μm),流动相为甲醇 0.1 mol/L的乙酸铵水溶液(75 25,V/V),柱温30 ℃,流速0.2 mL/min,进样量20 μL.质谱条件为电喷雾离子源(ESI-),多反应监测(MRM)方式进行采集;DNC-D8同位素内标法定量.结果表明,DNC在10～500 ng/mL浓度范围内呈现良好的线性关系,R2为0.999 7;鸡蛋和鸡肉中DNC残留检测方法检测限均为0.5 ng/g,定量限均为1 ng/g;鸡蛋中从2、5和10 ng/g三个添加浓度检测结果可以看出,方法平均回收率为95.9%～102.2%,批内RSD为0.9%～4.4%,批间RSD为0.3%～2.1%.鸡肉组织从100、200和300 ng/g三个添加浓度检测结果可以看出,方法平均回收率为94.0%～103.3%,批内RSD为2.0%～6.3%,批间RSD为3.1%～5.2%.     

HPLC法测定中兽药散剂中非法添加的10种磺胺类药物

建立了中兽药散剂中非法添加10种磺胺类药物测定的高效液相色谱方法。液相色谱条件为:色谱柱C_(18)柱150 mm×4.6 mm(i.d.),5μm;流动相:乙腈-甲醇-2%乙酸溶液(15+5+80);流速:1.0 mL/min;柱温:30℃;检测波长:270 nm;进样量10μL。结果表明,10种磺胺类药物在50~800 ng/mL浓度范围内呈现良好线性关系,相关系数R~2均大于0.995,方法检测限为5μg/g,从5、10和20 mg/g 3个添加浓度检测结果可以看出,方法平均回收率为85.4%~106.8%(n=6),批内批间RSD均小于10%。     

高效液相-串联质谱法测定蜂蜜中利巴韦林残留研究

本研究采用同位素内标法建立了蜂蜜中利巴韦林残留液相色谱-串联质谱方法。样品经提取后经混合型阳离子交换固相萃取净化后上机测定,色谱柱为Hypercarb多孔石墨碳色谱柱(100 mm×2.1 mm,5μm),以0.1%(V/V)甲酸甲醇-0.1%(V/V)甲酸水为流动相进行梯度洗脱,采用电喷雾正离子(ESI⁺)和多反应监测(MRM)模式测定,同位素内标法定量。结果显示,利巴韦林进样浓度在2～100 ng/mL浓度范围内呈良好的线性关系(R²=0.9995);方法检出限和定量限分别为1μg/kg和2μg/kg;2、4、20μg/kg三个添加水平下,回收率在67.6%～112.7%之间,批内、批间相对标准偏差均小于15%。本方法简便、准确、快速、灵敏,适用于蜂蜜中利巴韦林残留检测。     

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。