吖啶橙免疫荧光菌团法快速检测鱼贝类副溶血性弧菌的研究

本研究建立了适用于检测鱼贝类副溶血性弧菌的吖啶橙免疫荧光菌团培养—沉淀法.用该法可检出每毫升含10万个细菌的菌悬液,不与沙门氏菌、大肠杆菌、猪丹毒杆菌等7种杂菌发生交叉反应.采用随机抽样法对从长春市各大市场采集的351份海产鱼贝类样品进行了检测,其阳性率为46.4%,常规培养法检出率为49.8%,两者相差不显著(P>0.05).该法可在27h之内报告结果,而常规培养法需5～7d.该法具有特异性强、敏感性高、简便快速、所需仪器简单等特点,适用于大样本的检测和基层单位使用.     

生物素-亲和素斑点酶联免疫吸附试验快速检测鱼源副溶血性弧菌的研究

本研究建立了快速检测鱼源副溶血性弧菌的BA-Dot-ELISA方法.用该法可检出每毫升接种10个菌,增菌18h的培养物.该法敏感性为10~4个/mL,比Dot-ELISA敏感10～100倍.不与溶藻性弧菌、亲水气单胞菌等13种杂菌发生交叉反应.增菌前杂菌多于副溶血性弧菌10~6时,对检测结果有影响.可在22～24h报告结果,比常规培养法快4～6d以该法对带鱼、小黄花鱼、马面鱼、鲤鱼等311份样本进行检测,检出率分别为47.0%、41.7%、14.8%和11.8%,与常规培养法相差不显著(P>0.05).生化试验复检结果表明,检出的阳性可凝菌株均为副溶血性弧菌.该法适用于在短时间内对大批样本的检测.     

吖啶橙免疫荧光菌团法快速检测鱼源红斑丹毒丝菌的实验研究

研究建立了快速检测红斑丹毒丝菌的吖啶橙免疫荧光菌团离心培养法。该方法能检出560个菌在选择性肉汤中10h的培养物或每毫升含5×10~4个菌的抗原悬液;不与李氏杆菌等16种其他细菌发生反应;操作简便,不需要特殊的仪器设备,可于15～18h内报告结果(常规分离法需2～3d);应用离心培养法与常规分离法检测了325尾鲜鱼,阳性率分别为48.0％和55.7％,两者无显著差异(p>0.05)。从鱼体分离出的红斑丹毒丝菌的大多数菌株(18/19)具有毒力;对分离菌株的血清型鉴定发现,有3株菌可能是新的血清型。     

McAb·ELISA间接法对毛皮动物空肠弯曲菌快速检测的研究

用McAb作第一抗体,建立快速检测毛皮动物空肠弯曲菌的ELISA间接法。该方法具有敏感、特异、快速、简便等特点,可检出每毫升含10个菌的24小时培养标木,不与鳗弧菌等28种参照菌及混合菌液发生交叉反应,并在27小时内报告结果。对狐等5种毛皮动物265份肛拭粪便标本进行检测,其总阳性检出率为31.3％,与常规分离鉴定法的符合率为97.5％,相差不显著(P>0.05)。     

间接ELISA对鸡猪空肠弯曲菌快速检验的实验研究

以方阵滴定法确定了空肠弯曲菌抗血清、酶结合物的最佳工作浓度和孵育时间,从而立了快速检测空肠弯曲菌的间接ELISA。该试验可检出含8～10个空肠弯曲菌经24h培养的标本(含30万个菌/ml的肉汤培养物);不与沙门氏菌等15种对照菌及其混合液发生交叉反应。以鸡源和猪源空肠弯曲菌抗血清分别作为ELISA的第一抗体,对144份鸡泄殖腔粪便标本和116份猪直肠粪便标本的选择性增菌肉汤培养物进行了检测。其阳性率分别为83.3％和79.3％,可于28h内报告结果;常规法对上述标本的阳性检出率分别为85.4％和81％,但程序繁琐,需5～7d方能获得最终检查结果。两种方法对鸡、猪粪便标本检测结果的阳性符合率,分别为97.5％与97.9％。     

吖啶橙免疫荧光菌团法对肉品和鲜乳中小肠结肠耶氏菌快速检出的实验研究

对应用吖啶橙免疫荧光菌团法(培养法和沉淀法)快速检出小肠结肠耶氏菌的敏感性和特异性进行了实验研究,进而应用先增菌再菌团法的检测程序,对肉品模拟标本和198份肉品和鲜乳实际样品进行了检测,并与常规分离培养法作了对比,证明菌团法于13.5×10~2～10~3个攻/ml以上时,出现典型荧光菌团,与13种杂菌不形成菌团交叉;与杂菌比在1:400以下菌团形成不受干扰;与常规培养法的阳性检出率无显著差异(P>0.05);40h以内即可获得结果,较常规分离培养时间(一般4d左右)大为缩短。     

空肠弯曲菌共同抗原单克隆抗体的研制及其在细菌检验中应用——Ⅲ.在细菌快速检验中的应用

应用抗空肠弯曲菌共同抗原的单克隆抗体(4A7),建立了适用于空肠弯曲菌快速检验的间接-ELISA和BA-ELISA。两种方法的特异性检查表明,对受试的32种其它细菌,除与幽门弯曲菌发生交叉反应外,其余均为阴性反应。对空弯菌纯培养物检测的敏感性,BA-ELISA为3.2×104个菌/mL,间接-ELISA为1.6×105个菌/mL;对细菌动态培养物检测,BA-ELISA可检出接种约5个菌/mL、间接-ELISA可检出接种约10个菌/mL的24 h增菌培养物。应用BA-ELISA对人(140份)、猪(140份)、禽类(364份)及特种经济动物(265份)标本进行检测,阳性率依次为121%、52%、58.2%和32.8%;应用间接-ELISA对人(140份)、禽类(222份)及特种经济动物(265份)标本进行检测,阳性率依次为11.4%、61.7%、31.3%。两种方法的结果均与常规培养法相差不显著,可在27h内报告结果。     

吖啶橙免疫荧光菌团培养法对沙门氏菌的快速检测

本实验通过用吖啶橙免疫荧光菌团培养法对快速检测沙门氏菌的特异性和敏感性进行了研究,对肉品模拟标本,通过先增菌再用菌团培养法进行检测,证明该检测方法对于34个菌/ml的沙门氏菌均可检出;与枯草杆菌、大肠埃希氏杆菌等八种杂菌均不形成菌团交叉。与杂菌的浓度比在1∶640之内均不受干扰。对125份样品进行检测,并与常规方法进行比较,相差不显著。运用本检测方法,30小时即可获得结果(而常规方法则一般需要4～6天),大大缩短了检测时间。所以吖啶橙免疫荧光菌团培养法对沙门氏菌的快速检测是一种敏感性高、特异性强、简便快速、所需仪器简单的检测方法。     

动物性饲料中沙门氏菌快速检验的研究——协同凝集试验及HRP-SPA酶染色法的应用

本研究确定了适用于动物性饲料中沙门氏菌检验的增菌程序、协同凝集试验(COAG)及HRP—SPA染色法(酶染法)的最适实验条件。以这种条件进行增菌,并以COAG及酶染法进行检查,具有快度、敏感、特异性强的优点。应用COAG、酶染法及沙门氏菌常规分离鉴定法,对236份动物性饲料标本进行了检测。结果两种快速法与常规法有较好的符合率,酶染法在检出阳性标本上优于常规法.且可在16～18h内报告结果,比常规法的时间明显缩短。因此认为,COAG和酶染法适用于动物性饲料中沙门氏菌的快速检测。动物性饲料的沙门氏菌污染,依饲料的种类不同而异,其中鱼粉为31.5％、血粉25％骨粉10.3％,平均为17.4％,而且存在着多种血清型的沙门氏菌,其中以鼠伤寒沙门氏菌占优势。因此认为动物性饲料中的沙门氏菌污染在人畜沙门氏菌的流行病学上具有重要的作用。     

牛源胎儿弯曲菌PCR检测方法的建立

根据胎儿弯曲菌的16S rRNA基因序列设计引物,以微需氧培养的胎儿弯曲菌标准株菌体裂解物为模板,进行PCR扩增目的片段。同法检测了胎儿弯曲菌的10个参考菌株,结果均为阳性。采用异硫氰酸胍快速提取流产牛阴道分泌物中胎儿弯曲菌的DNA,然后用PCR方法检测,5份样品阳性,该试验可在24 h内完成,比病原分离法快5~7 d;而检测空肠弯曲菌、大肠杆菌、布氏杆菌、葡萄球菌、链球菌等相关病原时,均无特异性扩增产物,表明该检测方法具有快速、特异、实用性强的特点。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein