用免疫过氧化物酶染色法检查犬组织内杜氏利什曼原虫

这篇论文描述用免疫过氧化物酶染色法检查犬组织中的杜氏利什曼原虫无鞭毛体。把间接免疫过氧化物酶染色法用于诊断患利什曼原虫病犬的组织的检查。用5%草酸消除含铁血黄素色素,杜氏利什曼原虫的无鞭毛体现深褐色,其与用苏木素染色的宿主细胞形成对照。在用对照血清孵育的切片中则看不到任何呈阳性染色的无鞭毛体。较常出现利什曼原虫的器官有:皮肤(巨噬细胞和成纤维细胞)、肝脏、脾脏、淋巴结和骨髓。有少数几个病例,在其肾脏、肠、肾上腺、眼及睾丸见到无鞭毛体。该技术操作简易、重复性好,可对犬利什曼病做出明确的组织病理学诊断。至今,对感染狗组织中利什曼原虫无鞭毛体的检测仍依靠苏木素、伊红或姬姆萨染色法。当犬组织中含有适当数量虫体时,姬姆萨染色法是一种最佳、最简单的诊断方法。然而,在许多犬中,在不同器官中虫体却很少,在这些病例,采用姬姆萨染色法检查则很困难,且不易确诊。在犬利什曼原虫病呈地方性流行的地中海国家,该问题十分重要。需要一种能够快速、更灵敏而特异确诊本病的技术。尤其在寄生虫少量出现时。Sells 和 Burton(1981)成功地应用免疫过氧化物酶染色法对实验性感染鼠以及人组织中的利什曼原虫进行了检查。本次试验对他们的方法加以改进,检查了犬组织中感染的杜氏利什曼原虫。     

利什曼原虫候选疫苗佐剂的研究进展

利什曼原虫病是由利什曼原虫属的前鞭毛体引起的一种寄生虫性疾病,通过媒介昆虫的叮咬而传播,可感染许多哺乳动物。根据利什曼原虫在哺乳动物组织中的寄生部位,可将利什曼原虫病分为内脏利什曼原虫病、皮肤利什曼原虫病及黏膜利什曼原虫病,其中内脏利什曼原虫病危害最大[1]。目前,通过     

利什曼原虫候选疫苗佐剂的研究进展

利什曼原虫病是由利什曼原虫属的前鞭毛体引起的一种寄生虫性疾病,通过媒介昆虫的叮咬而传播,可感染许多哺乳动物.根据利什曼原虫在哺乳动物组织中的寄生部位,可将利什曼原虫病分为内脏利什曼原虫病、皮肤利什曼原虫病及黏膜利什曼原虫病,其中内脏利什曼原虫病危害最大[1].目前,通过注射疫苗预防利什曼原虫病在世界范围内已逐渐被认可.     

硝唑尼特对斑马鱼和赤子爱胜蚓的急性毒性试验

通过对斑马鱼和赤子爱胜蚓的急性毒性试验,研究了硝唑尼特的生态毒性.结果表明,硝唑尼特在静水条件下对斑马鱼24 h LC50为2.312 mg/L、48 h和72 h LC50为2.033 mg/L、96 h LC50为1.968 mg/L,按鱼类急性毒性分级标准,硝唑尼特属高毒类物质;硝唑尼特滤纸法对赤子爱胜蚓24 h...     

抗寄生虫新药硝唑尼特研究进展

硝唑尼特是一种新的广谱、高效抗寄生虫和微生物药物,对多种原虫、吸虫、线虫、蠕虫感染和敏感肠道菌感染有特效。综述了硝唑尼特的理化性质、药理学特征和临床应用等方面的研究进展,以期推进该药早日在我国兽医临床得到应用。     

新型抗原虫药硝唑尼特

<正>硝唑尼特(nitazoxanid,NTZ)是一种新的抗原虫药,由Romark实验室创制,首次报道于1976年,化学名称苯酚乙酸酯。2002年由美国FDA批准硝唑尼特液体制剂治疗隐孢子虫病和肠贾第鞭毛虫所致1~11岁儿童的腹泻。在国内,中国农业科学院上海兽医研究所对硝唑尼特及其混悬剂进行了研究,但至今仍未上市,也无该产品     

鸡组织滴虫病及其防治措施

1病原 组织滴虫是很小的原虫。该原虫有2种形式,组织型原虫,寄生于肠壁和肝组织中的虫体没有鞭毛,呈圆形、卵圆形和阿米巴形,大小约为6~20微米;肠腔型原虫,寄生在盲肠腔的内容物中,虫体呈阿米巴状,直径为5~30微米,具有1根鞭毛,在显微镜下可以看到鞭毛的运动。     

硝唑尼特的多重作用机制及应用研究进展

硝唑尼特(NTZ)是上世纪七十年代开发的一个抗寄生虫药物,已被美国食品药品监督管理局(FDA)批准用于治疗隐孢子虫或蓝氏贾第鞭毛虫引起的腹泻,被中国农业农村部批准用于治疗犬绦虫病。近年来的研究发现,硝唑尼特不仅能抗多种寄生虫,而且对多种危害严重的人或动物病原菌、病毒也具有很好的活性,但是研究发现硝唑尼特对各种病原体的活性作用机制却各不相同。本文主要综述了硝唑尼特对多种病原体的作用及其可能的机制,从而为硝唑尼特的利用和相关研究提供资料。     

鸡组织滴虫病的诊治

组织滴虫病又称盲肠肝炎、黑头病和单胞虫病,是一种由组织滴虫引起的导致鸡盲肠发炎、肝脏坏死的急性原虫病。该原虫有两种形式：一种是组织型原虫,寄生在细胞里,虫体呈圆形或卵圆形,没有鞭毛,大小为6～20μm;另一种是肠腔型原虫,寄生在盲肠腔内容物中,虫体呈阿米巴状,直径为5~30μm,有一根鞭毛,在显微镜下可以看到鞭毛的运动...     

细胞内寄生虫抑制细胞凋亡的机制

宿主有效地防御机制使寄生在细胞内的虫体发展了多种调节宿主细胞凋亡的途径。刚第弓形虫、杜氏锥虫、利什曼原虫、泰勒虫等都可抑制宿主细胞的凋亡进程而为自身的复制和寄生生活的持续提供了有利的环境,尽管它们进入细胞的机制和在细胞中的定位不同,但都激活相似的途径而发挥抑制作用。目前已知有2个家族的蛋白分子能够打破凋亡进程,一是寄生虫依赖的核因子κappaB,另一个是寄生虫感染诱导表达的热休克蛋白。其确切的分子机制尚不清楚。     

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