高效液相-串联质谱法测定鸡肉中泰妙菌素残留的研究

建立了固相萃取-高效液相色谱-串联质谱法测定鸡肉中泰妙菌素残留的分析方法。试样经磷酸盐缓冲液(pH8.0)-乙酸乙酯混合提取,经水饱和正己烷除脂后,过MCX固相萃取小柱净化,采用HPLC-MS/MS电喷雾电离正离子扫描,多反应监测模式(MRM)检测,内标法定量。泰妙菌素在0.5~50μg/L的浓度范围内呈现良好的线性关系,相关系数R2大于0.999。其检测限为0.25μg/kg,定量限为0.5μg/kg。     

高效液相-串联质谱法测定猪、牛和羊尿液中18种同化激素的含量

建立了高效液相色谱-串联质谱(HPLC-MS/MS)检测动物尿液18种同化激素的方法。动物尿液在37 ℃（±0.5℃）下酶解16 h后，调节pH=7.0（±0.5℃），C18固相萃取柱净化，用HPLC-MS/MS进行检测。18种同化激素在1~ 500 μg/L浓度范围内线性关系良好(r2≥0.99)，回收率在70.9 ~112%之间，日内变异系数范围为1.2 ~ 13.1%，日间变异系数范围为3.5~16.7%，检测限为0.5 μg/kg，定量限为1.0 μg/kg。本方法操作简便，灵敏度高，适用于动物尿液中18种同化激素的同时测定。     

高效液相色谱串联质谱法同时测定畜禽粪便中多种抗生素方法的研究

建立了高效液相色谱-串联质谱(HPLC-MS/MS)同时检测畜禽粪便中四环素类、磺胺类、喹诺酮类、大环内酯类26种化合物的方法。畜禽粪便冷冻干燥粉碎，HLB固相萃取柱净化，用HPLC-MS/MS进行检测。26种化合物在5～200 ng/mL浓度范围内线性关系良好(r²≥0.99),回收率在70.1%～99.1%之间，日内变异系数范围为1.3%～13.0%,日间变异系数范围为1.6%～14.7%,检测限为2～5μg/kg,定量限为5～10μg/kg。本方法操作简便，灵敏度高，适用于猪和鸡粪便中26种化合物的同时测定。     

高效液相色谱-串联质谱法研究猪毛发中克仑特罗和莱克多巴胺的残留及代谢规律

建立了高效液相色谱-串联质谱(HPLC-MS/MS)同时检测猪毛发中克仑特罗和莱克多巴胺残留的方法。猪毛发经1 mol/L氢氧化钠溶液水解、乙酸乙酯萃取、MCX固相萃取柱净化,流动相溶解后用HPLC-MS/MS进行检测。克仑特罗在1.9～463.2 ng/mL浓度范围内线性关系良好(R2=0.999 0);回收率为83.3%～86.6%,相对标准偏差为6.7%～9.2%;检出限为0.3μg/kg,定量限为0.8μg/kg。莱克多巴胺在2.8～562.9 ng/mL浓度范围内线性关系良好(R2=0.999 2);回收率为83.4%～88.4%,相对标准偏差为7.2%～9.6%;检出限为0.4μg/kg,定量限为1.2μg/kg。应用该方法研究了克仑特罗、莱克多巴胺在猪毛发中的代谢规律并进行了猪毛发样品检测。结果喂药7 d至停药21 d猪毛发中均检出克仑特罗、莱克多巴胺残留;检测猪毛发样品25份,1份样品检出克仑特罗,残留量为58.68μg/kg。     

猪肉及组织中β-受体激动剂UPLC-MS/M检测方法研究

超高效液相色谱串联质谱法(UPLC-MS/MS)检测猪肉中克伦特罗、莱克多巴胺、沙丁胺醇3种β-受体激动剂残留方法.选用盐酸葡萄糖醛苷酶/芳基硫酸酯酶水解,混合型阳离子交换固相萃取净化,以0.1%甲酸水溶液-0.1%甲酸乙腈溶液-甲醇为流动相,超高效液相色谱串联质谱法检测,在1.0、5.0、10μg/kg浓度添加水平,空白肌肉组织中3种药物添加平均回收率范围84~95%,标准偏差3.6~8.1%.该方法检测限为0.1μg/kg,定量限为0.3μg/kg,具有准确敏感特性.     

超高效液相色谱-串联质谱法测定猪肉、猪肝及猪尿中的阿托品残留

建立了猪肉、猪肝和猪尿中阿托品残留的超高效液相色谱-串联质谱(UPLC-MS/MS)的检测方法。样品经乙腈-0.1%甲酸水(V/V,90:10)溶液提取,Agela Cleanert? PEP-2固相萃取柱净化后,采用UPLC-MS/MS测定,外标法定量。结果表明,猪组织及猪尿中阿托品的检测限为0.2 μg/kg,定量限为0.5 μg/kg。在0.5～2.5 μg/kg添加浓度范围内阿托品的平均回收率78.3%～98.2%之间,批内、批间相对标准偏差均小于15％。该方法简便、快速、灵敏度高、重现性好,适用于猪组织及猪尿中阿托品的含量测定。     

牛肝中苯并咪唑类药物残留的高效液相色谱检测方法

建立了牛肝组织中苯并咪唑类药物(阿苯哒唑,噻苯哒唑和奥芬哒唑)多残留检测的高效液相色谱法.用乙酸乙酯提取牛肝组织样品中的药物,提取液浓缩后加入酸性乙醇和正己烷分配脱脂,过C18固相萃取柱净化.以甲醇-磷酸二氢铵缓冲液为流动相,反相高效液相色谱紫外检测法检测.方法的平均回收率为78.8%,平均变异系数为2.18%.3种药物的检测限为8 μg/kg,定量限为25 μg/kg.     

气相色谱-质谱法快速测定猪尿中地西泮

建立了猪尿中地西泮的气相色谱-质谱(GC/MS)检测方法.样品经C18固相萃取柱净化后进行气相色谱-质谱测定.结果表明,方法定量限为0.5 μg/L,线性范围为10～500 μg/L.在三个添加浓度2、4、6 μg/L水平上,地西泮的平均回收率为 70%～120%,批内相对标准偏差< 20%、批间相对标准偏差< 12%.     

超高效液相色谱-串联质谱法测定鸡饲料中地克珠利的含量

本试验建立了鸡饲料中地克珠利(DIC)含量检测的超高效液相色谱-串联质谱分析方法。采用乙腈提取饲料中的药物,经硅胶固相萃取小柱净化后,超高效液相色谱-串联质谱法(UPLC-MS/MS)分析。整个色谱总时间为3.5 min。结果表明,在5、50、500μg/kg(仅配合饲料)和2000μg/kg(仅预混合饲料)的浓度添加水平下,饲料中地克珠利的回收率范围为90.28%～97.16%;日内变异系数范围为9.24%～14.10%,日间变异系数范围为9.73%～14.87%。以3倍信噪比为检测限,10倍信噪比为定量限,得出该方法的检测限为2.0μg/kg,定量限为5.0μg/kg。该方法操作简单,灵敏度、准确度和精密度均符合饲料中药物添加剂分析的技术要求,能够满足饲料中地克珠利的含量测定需求。     

高效液相色谱串联质谱法检测家禽组织中氯霉素残留量的研究

为了检测氯霉素在家禽组织中的残留量,本文建立了一种超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。通过对肌肉和鸡蛋样品采用碱性乙酸乙酯提取,20%甲醇水饱和正己烷液萃取净化,对鸡的肝脏和肾脏样品采用β-葡萄糖醛酸苷酶酶解后采用乙酸乙酯提取,C18固相萃取柱(500mg/3cc)净化,进行液相色谱-串联质谱负离子模式测定。结果表明,氯霉素在0.5~10.0ng/mL范围内均呈现良好的线性关系,相关系数(r)均大于0.990;样品中氯霉素的检测限为0.1μg/kg,定量限为0.2μg/kg。UPLC-MS/MS对氯霉素在0.2、0.4、2μg/kg范围内的平均回收率均为70%~120%,相对标准偏差均小于20%。     

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。