高效液相色谱法测定饲料中喹乙醇的含量

实验建立了饲料中喹乙醇经过固相萃取净化后用高效液相色谱仪定量检测的方法。饲料经70%甲醇溶液提取、离心后,经中性氧化铝小柱净化后,过0.45μm滤膜上机定量测定。实验结果表明,喹乙醇浓度为0.1～100.0μg/ml时具有良好的线性关系,饲料中喹乙醇回收率范围均在80%～110%。与国家标准GB/T8381.7—2005《饲料中喹乙醇的测定:高效液相色谱法》相比,本方法的实验结果不仅完全符合国家标准的要求,增加的净化过程更能有效地保护高效液相色谱系统。     

猪饲料中莱克多巴胺的GC/MS快速测定

本实验对猪饲料中莱克多巴胺的气相色谱-质谱快速检测方法进行了研究.采用酸性甲醇-水提取饲料中的莱克多巴胺,经乙酸乙酯萃取和酸性氧化铝固相萃取柱净化,衍生化后用气相色谱-质谱法检测和确证.结果表明,方法平均回收率为70.8%～83.8%,日间变异系数为4.5%～11.1%(n=3),配合饲料检测限和定量限分别为0.5μg/g和1.0 μg/g,预混合饲料检测限和定量限分别为0.3 μg/g和0.7 μg/g.该方法适合饲料中莱克多巴胺的确证和定量分析.     

超高效液相色谱-串联质谱法检测饲料中喹烯酮和喹乙醇

本文应用超高效液相色谱-串联质谱技术,建立了饲料中喹烯酮和喹乙醇的检测方法。样品经0.1%甲酸乙腈溶液提取后,通过PRiME HLB固相萃取柱净化;采用0.1%甲酸乙腈溶液作为流动相进行梯度洗脱,经AtlantisT3色谱柱分离,通过多反应监测模式进行测定。在5～500 ng/mL时线性关系良好,相关系数均大于0.996。在0.2、0.4、2 mg/kg添加水平下,平均回收率为80%～95.5%,相对标准偏差均小于10%。检测限为0.06 mg/kg,定量限为0.2 mg/kg,该法准确、简单、快速。     

超高效液相色谱法测定饲料中地昔尼尔

本研究建立了超高效液相色谱测定饲料中地昔尼尔的方法。饲料样品经过乙腈提取,取5mL上清液氮气吹干,用20%甲醇溶液(含0.2%甲酸)溶解,经过Waters Oasis MCX固相萃取小柱净化,然后用Waters Acquity UPLC HSS T3色谱柱(2.1mm×100mmi.d.,1.8μm)分离,以甲醇和水为流动相进行洗脱,外标法定量。结果表明,地昔尼尔质量浓度在0.05～100μg/mL内线性良好,相关系数大于0.9999;在10～200mg/kg的添加水平,平均加标回收率为78.0%～86.3%;相对标准偏差为4.2%～6.1%;方法的检出限低至0.05mg/kg,定量下限低至0.1mg/kg。该方法简单、快速、灵敏,可满足饲料中地昔尼尔的快速筛选检测的要求。     

超高效液相色谱-电喷雾串联质谱法测定饲料中地昔尼尔

实验建立了超高效液相色谱-串联质谱测定饲料中地昔尼尔的方法。饲料样品经过乙腈提取,取部分上清液氮气吹干,用20%甲醇溶液(含0.2%甲酸)溶解,经过Waters Oasis MCX固相萃取小柱净化,然后用Waters Acquity UPLC HSS T3色谱柱(2.1mm×100mm i.d.,1.8μm)分离,以甲醇和水为流动相进行洗脱,外标法定量。对前处理及液相色谱和质谱条件进行优化。结果表明,地昔尼尔质量浓度在1～500μg/l范围内线性良好,相关系数大于0.998;在10～200μg/kg的添加水平,平均加标回收率为74.2%～83.8%;相对标准偏差为5.5%～7.5%;方法的检出限低至1.0μg/kg,定量下限低至2.0μg/kg。该方法灵敏、稳定性好,可满足饲料中地昔尼尔的检测与确证的要求。     

气相色谱/质谱法测定饲料中三唑仑的含量

本实验建立了检测饲料中三唑仑的气相色谱/质谱法。样品经有机溶剂提取,阳离子固相萃取小柱净化后注入气相色谱质谱仪进行测定,并且经质谱确证。结果表明,三唑仑在0.1～5.0μg/mL范围内具有良好的线性关系,方法的回收率、精密度较高。     

LC-MS/MS结合定量触发相关MS/MS扫描功能同时定性确证和定量测定饲料中的违禁药物喹乙醇

本实验利用定量触发相关MS/MS扫描(QED-MS/MS)功能,建立饲料中喹乙醇的同时定性确证和定量测定LC-MS/MS方法。饲料中喹乙醇经5%甲醇-水溶液提取,Oasis HLB固相萃取柱净化后,通过LC-MS/MS分析。LC-MS/MS采用Zorbax SB C18柱(3.5μm,2.1×150 mm),0.2%乙酸-甲醇梯度洗脱,加热电喷雾离子化,选择性反应监测m/z 264>212作为定量测定,同时以数据依赖扫描模式对m/z 150～265扫描,作为定性确证结果。结果表明:本方法在0.2～10 mg/kg范围内线性关系良好,最低同时定性定量限为0.2 mg/kg。因此基于QED-MS/MS的LC-MS/MS方法可用于饲料中喹乙醇的检测。     

牛肝中氯舒隆残留检测高效液相色谱-串联质谱法研究

研究了采用固相萃取净化,高效液相色谱-串联质谱(HPLC-MS/MS)法测定牛肝中氯舒隆残留量的方法.样品用乙腈提取,HLB固相萃取小柱净化后,HPLC-MS/MS方法检测.离子源采用电喷雾负离子方式(ESI-),多反应监测(MRM)模式进行采集,外标法定量.结果表明:方法检测限为2 μg/kg,定量限为5 μg/kg.在5、20、100 μg/kg三个添加浓度范围内,方法的平均回收率为86.6%～93.5%;方法RSD≤6.8%.     

高效液相色谱串联质谱法测定渔业水体及渔业饲料中的五氯苯酚

本文建立了一种简单、快速测定渔业水体和渔业饲料中五氯苯酚的液相色谱串联质谱分析方法。渔业水体采取固相萃取进行富集净化,渔业饲料样品经氨化乙腈提取,MAX固相萃取小柱净化,质谱采用选择反应监测负离子模式测定进行分析。结果表明:方法线性为0.5～50 ng/mL,相关系数大于0.9999;渔业水体的检出限(LOD)和定量限(LOQ)为0.05μg/L和0.1μg/L,渔业饲料的LOD和LOQ为0.8μg/kg和1.6μg/kg,该方法在水样和渔业饲料样品中的平均加标回收率为78.6%～92.1%。采用该方法对长沙市周边的湖泊和池塘地表水和渔业饲料样品进行检测,在水样中测得五氯苯酚浓度为0.64～1.22μg/L。     

超高效液相色谱-串联质谱法测定饲料中的恩诺沙星和喹乙醇药物的含量

试验建立了同时测定饲料中恩诺沙星和喹乙醇药物含量的超高效液相色谱-串联质谱(UPLC/MS/MS)分析方法。采用80%乙腈(含1%甲酸)作为样品的提取溶液,经HLB固相萃取柱净化后上机测定。在正离子模式下通过两对离子对进行定性和定量分析。结果显示,恩诺沙星和喹乙醇在5~100μg/l范围内线性关系良好,相关系数r均大于0.998;空白饲料在0.1、0.2、0.5 mg/kg的添加浓度上的回收率均在70%~90%之间;批内、批间相对偏差(RSD)均小于20%;本方法对饲料中恩诺沙星和喹乙醇的定量限为0.1 mg/kg(S/N10),检测限为0.05 mg/kg(S/N3)。     

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.