国内外克伦特罗ELISA检测试剂盒评价

根据B/B0-50%抑制浓度、检测范围、标准溶液浓度梯度、板内变异、板间变异、样品添加检验、实际样品检验等方面的比较结果对两种克伦特罗ELISA检测试剂盒(A: 中国兽医药品监察所研制, B: 德国 r-Biopharm公司研制)进行评价。结果表明,试剂盒A的50%抑制浓度低于1.0 ng/mL; 检测范围在0.10~3.0 ng/mL之间;标准溶液浓度梯度中包括1.0 ng/mL这一限定值;板内变异系数小于13.7%,板间变异系数小于8.8%;样品回收率在70%~110%之间;实际样品检验和试剂盒B检样的阳性符合率为95.5%。试验证明,试剂盒A与试剂盒B的水平相当。     

食品中呋喃妥因代谢物酶联免疫检测试剂盒的研制

目的：开发研制快速检测呋喃妥因代谢物的酶联免疫检测试剂盒。方法：依据直接竞争ELISA原理,采用棋盘包被法确定最佳抗体包被浓度和酶标抗原工作浓度、包被条件、反应时间、底物显色时间等,并对试剂盒的各项技术指标进行确认。结果：成功的组装了呋喃妥因的酶联免疫检测试剂盒,并建立了肌肉、肝脏、水产、蜂蜜等的前处理方法,检测限均远低于1μg／kg。该试剂盒线性检测范围为0～4．05ng／mL,IC。浮动范围0．30～0．60ng／mL,样品的板内、批内、批间的变异系数均小于15％,平均回收率在65％～90％之间,与其同类药物的交叉反应率均小于O-2％。结论：本研究研制的试刺盒重复性、再现性、特异性、稳定性各项指标均符合技术要求,可用于动物源性食品中呋喃妥因代谢物残留的检测。     

3种ELISA试剂盒检测盐酸克伦特罗效果评价

用3种盐酸克伦特罗ELISA检测试剂盒对10份未知猪尿液样品及5份标准浓度猪尿液样品进行检测，以比较试剂盒的检测效果。结果表明，试剂盒A在盐酸克伦特罗浓度为0ng／mL-10ng／mL的范围内其检测结果较准确，当浓度大于10ng／mL时其检测结果偏小；试剂盒B对盐酸克伦特罗的检测结果较标准样品浓度有时偏高，有时偏低，结果不够准确；试剂盒C的检测结果与标准样品的实际浓度相近，结果较准确。稳定性方面，试剂盒B的稳定性差，而试剂盒A及试剂盒C的稳定性较好。总的来说，试剂盒C在检测结果的准确性和稳定性上均较好，是3种试剂盒中效果最为理想的盐酸克伦特罗检测试剂盒。     

不同细胞因子对水牛原始生殖细胞传代培养的影响

为探讨不同细胞因子对水牛原始生殖细胞（PGCs）传代培养的影响，将PGCs分别采用A、B、C、D、E、F和G共7种培养基进行培养，即A组：基础液＋10ng／mL白血病抑制因子（LIF）＋10ng／mL碱性成纤维细胞生长因子（bFGF）；B组：基础液＋20ng／mL LIF＋20ng／mL bFGF；C组：基础液＋20ng／mL LIF＋10ng／mL bFGF；D组：基础液＋20ng／mL LIF；E组：基础液＋20ng／mL LIF＋20ng／mL bFGF＋20ng／mL干细胞因子（SCF）；F组：基础液＋20ng／mL LIF＋40ng／mL bFGF＋40ng／mL SCF；G组（对照组）：基础液。将机械法分离的PGCs小集落接种到水牛胎儿成纤维细胞（BEF）饲养层上进行传代培养。结果，原代时，A、B、C、D、E和F组的克隆数目都显著高于对照组（P％0．05），其中E和F组的克隆数目显著高于A组（P〈0．05），而与B、C、D组差异均不显著（P〉0．05）；1～8代时，B、C、D、E、F组的克隆数目显著高于A组（P〈0．05）；对照组传代数仅为2代，A组为5代，而B、C、D、E和F组均为8代以上。结果表明，在传代过程中，LIF起主要作用，20ng／mL的LIF浓度可以满足水牛PGCs传代培养的需要。     

酶联免疫吸附法检测鸡肝肾中氯霉素残留的分析

试验用六种浓度的氯霉素标准品(0.025ng／mL,0.05ng／mL,0.1ng／mL,0.2ng／mL,0.5ng／mL,2ng/mL)做工作标准曲线,设计鸡肝脏、肾脏两个待测样品,同时分别加六种标准品于肝脏和肾脏中测定样品中氯霉素的回收率。试验结果表明:ELESA方法测定鸡组织中氯霉素的检出限为0.02ng／mL,样品中不同浓度的氯霉素标准品回收率均达84.8％以上。说明该方法灵敏、准确。     

氯霉素竞争ELISA检测方法的研究

用抗氯霉素的MAb 2G2建立了检测氯霉素的竞争ELISA,对主要影响因素进行了研究,其回归方程为y=0.3522x+0.5939,相关系数为RZ=0.9906,检测线性范围为0.098 ng/mL～25 ng/mL,半数抑制浓度(IC50)为1.848 ng/mL.检测限为0.135 ng/mL.与氯霉素琥珀酸钠交叉反应率为143%,与其它结构类似物和常见抗菌素的交叉反应率均小于0.01%.批内和批间变异系数分别为4.98%和9.42%,牛奶样的平均添加回收率为101.31%.所建立的检测氯霉素竞争ELISA法,符合检测氯霉素残留的要求,为氯霉素残留快速检测试剂盒的研制奠定了基础.     

食品中呋哺妥因代谢物酶联免疫检测试剂盒的研制

目的:开发研制快速检测呋喃妥因代谢物的酶联免疫检测试剂盒.方法:依据直接竞争ELISA原理,采用棋盘包被法确定最佳抗体包被浓度和酶标抗原工作浓度、包被条件、反应时间、底物显色时间等,并对试剂盒的各项技术指标进行确认.结果:成功的组装了呋喃妥因的酶联免疫检测试剂盒,并建立了肌肉、肝脏、水产、蜂蜜等的前处理方法,检测限均远低于1μg／kg.该试剂盒线性检测范围为0～4.05ng／mL,IC50浮动范围0.30～0.60ng/mL,样品的板内、批内、批间的变异系数均小于15％,平均回收率在65％～90％之间,与其同类药物的交叉反应率均小于0.2％.结论:本研究研制的试剂盒重复性、再现性、特异性、稳定性各项指标均符合技术要求,可用于动物源性食品中呋喃妥因代谢物残留的检测.     

两种克伦特罗ELISA试剂盒的比对试验

应用意大利Tecna公司和德国r-B iopharm公司的克伦特罗酶联免疫(ELISA)试剂盒检测猪尿样和猪肝样品,并对两者的标准曲线线性范围、斜率和B/B0抑制浓度、板内和板间变异系数、阳性检出率、回收率等进行了比对。结果表明,当阳性判定阈值设定在1.0~5.0 ng/mL范围时,2种试剂盒均能满足分析要求,对尿样检测Tecna试剂盒比r-B iopharm试剂盒的检测时间要短;但在检测低浓度克伦特罗的尿样时,r-B iop-harm试剂盒更好,对肝样检测Tecna试剂盒有优势。     

动物组织中磺胺二甲嘧啶残留检测ELISA试剂盒的研制

在建立竞争ELISA方法的基础上，首次研制出检测磺胺二甲嘧啶的单克隆抗体快速检测试剂盒，并对其检测限、精密度、检测范围以及鸡肌肉组织中的添加回收实验做了详细研究。本试剂盒的检测限为1．0ng／m1，检测范围为1．0-81．0ng／m1，批内变异系数＜8．9％，批间变异系数＜9．5％，在10、60和200ng／m1水平鸡肌肉组织中添加，回收率为64．5％-85．5％，变异系数为6．0％-18．6％。与同类相关德国产试剂盒相比较，阳性符合率为100％。     

猪肝和猪尿中沙丁胺醇和克伦特罗残留的酶联免疫吸附检测法研究

采用混合酸酐法将沙丁胺醇与牛血清白蛋白偶联，并免疫家兔制备抗沙丁胺醇抗血清。以间接ELISA法测定血清效价，测得抗血清最佳工作浓度为1：6400，该抗沙丁胺醇抗血清对克伦特罗有110％的交叉反应性。建立了能够同时检测SAL和CL的间接竞争ELISA方法，该方法对沙丁胺醇的检测范围为0．48ng／mL～8．0μg／mL，对克伦特罗的检测范围为0．43ng／mL～7．3μg／mL，对沙丁胺醇的检测灵敏度为o．48ng／mL，对克伦特罗的检测灵敏度为0．43ng／mL。在猪肝和猪尿中添加1～50ng／g(ng／mL)的沙丁胺醇，添加回收率为72．2％～84．8％，变异系数为4．2％～28．3％，在猪肝脏和猪尿中添加1～50ng／g(ng／mL)的克伦特罗，添加回收率为84．3％～103．4％，变异系数为O．3％～35．5％。     

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.     

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.     

Hypothalamic dopamine is required for salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the relationship between hypothalamic dopamine (DA) and salsolinol (SAL) for the secretion of prolactin (PRL) in goats. SAL or thyrotropin‐releasing hormone (TRH) was intravenously injected into female goats treated with or without the D₂ DA receptor antagonist haloperidol (Hal), which crosses the blood‐brain barrier, and the PRL‐releasing response to SAL was compared with that to TRH. PRL‐releasing responses to SAL, Hal, and Hal plus SAL were also examined after a pretreatment to augment central DA using carbidopa (Carbi) and L‐dopa. The PRL‐releasing response to Hal alone was greater than that to SAL or TRH alone. The PRL‐releasing response to Hal plus SAL was similar to that of Hal alone. In contrast, the PRL‐releasing response to Hal plus TRH was greater than that to TRH or Hal alone. The treatment with Carbi plus L‐dopa inhibited SAL‐ and Hal‐induced PRL secretion. The inhibition of the PRL‐releasing response to SAL disappeared when SAL was injected with Hal. These results indicate that the mechanisms underlying the SAL‐induced PRL response differ from those of TRH, and suggest that hypothalamic DA and its synthesis is associated in part with SAL‐induced PRL secretion in goats.     

Laboratory diagnosis of respiratory diseases of cattle

The authors describe the procedure of laboratory diagnosis for bovine respiratory diseases: direct diagnosis by isolation and for identification of bacteria or viruses and indirect diagnosis by serological methods. They specify the restraints and limits of this diagnosis and the significance results which are obtained and connected with knowledge of anamnestic information.     

The effect of peri-parturient anthelmintic treatment on the productivity of dairy cattle in subtropical western India

Trials with fenbendazole (Panacur, Hoechst India Ltd) were carried out on two commercial farms in subtropical western India to study the response and economics of nematode treatment in adult dairy cows. Milk yield, lactation length, time to first oestrus and worm egg output were monitored in treated and control groups. Treatment reduced the egg count considerably. Treated cows produced 142 litres more milk over 100 days (p<0.05), with extension of lactation length and advancement of time to first oestrus. The economic gain in terms of milk yield far outweighed the cost of anthelmintic used.     

An Evaluation of the Acceptability as Forage of Some Nutritive and Antinutritive Components and of the Dry Matter Degradation Profiles of Five Species of Ficus

The suitability of five species of Ficus, F. mucoso, F. thonningii, F. polita, F. religiosa and F. benjamina, for feeding ruminant livestock was studied. The nutritive and antinutritive components were determined and the acceptability of the forages to livestock was assessed using a cafeteria method in 8 adult small ruminants. Also, the degradation potential of the dry matter of the five Ficus species was investigated using 3 fistulated sheep. The crude protein (CP) content of the Ficus species varied significantly (p < 0.05), ranging from 130 to 180 g/kg DM. The content of neutral detergent fibre (NDF) also varied significantly (p < 0.05), ranging from 650 to 710 g/kg DM. The organic matter (OM) contents did not differ significantly (p > 0.05), having a mean value of 916 g/kg DM. The concentrations of tannin, saponin, phytic acid and oxalic acid were low. The acceptability of the forage was similar for four of the species but poor for F. polita. The extent of DM degradation varied significant among the Ficus species, the ranking order being F. benjamina > F. thonningii > F. mucoso > F. religiosa > F. polita.