补体损伤类鼻疽杆菌外膜的实验研究

分离获得的类鼻疽杆菌在抗血清和补体的作用下,进行了青霉素药敏试验和Ｌ型菌的形成试验。结果表明,类鼻疽杆菌虽然具有抵抗补体杀灭的特性,但补体激活所形成的膜攻击物可损伤类鼻疽杆菌的外膜,从而增强了其对青霉素的敏感性。从这一意义上讲,补体在抗类鼻疽杆菌感染的机制中已完成了杀菌的第一步。     

类鼻疽快速诊断的研究

对实验感染类鼻疽杆菌的豚鼠，以间接血凝试验检测证实，类鼻疽杆菌外毒素抗体于感染后４ｄ即可测得，１６～３２ｄ达高峰；而类鼻疽杆菌脂多糖抗体出现较慢，但维持时间长。用测定外毒素抗体的间接血凝试验对７例细菌分离阳性患者进行测试，以血清滴度≥１∶８０为临界值，其敏感性达１００％；对７０８名健康者测试，其特异性达９９％。在疫区，从感染性疾病中检出类鼻疽患者，测定外毒素抗体的间接血凝试验有重要的实用价值     

马骡非特异性鼻疽菌素眼反应的研究——Ⅰ、从鼻疽菌素点眼阳性反应马骡肺脏病变中分离的酵母样菌的初步鉴定

用于本试验的酵母样菌共12株。实验证明,这些菌与鼻疽杆菌和类鼻疽杆菌在免疫学上存在明显的交叉反应关系。为了便于感染这些菌的病例的鉴别诊断,根据形态特征、培养和生化特性以及血清反应等对这些酵母样菌进行了鉴定。     

应用白细胞粘附抑制试验对鼻疽马细胞免疫状态的探究Ⅱ.鼻疽杆菌接种马及不同类型自然感染鼻疽马的LAI试验

我们在基础试验和测定健马LAI正常值的基础上,应用白细胞粘附抑制试验,对鼻疽杆菌接种马及不同类型自然感染鼻疽马进行了检测,其结果如下。     

家畜类鼻疽疫源地调查

类鼻疽是热带地区的一种人畜共患传染病,我国华南地区处于热带,具有类鼻疽菌生长的自然条件,为了摸清类鼻疽疫源地在该地区的分布,我们对广东、广西及湖南三省区有关地区的家畜作了血清流行病学调查,并采取水样和家畜脏器病料作了类鼻疽菌分离,现将结果报告如下。     

波尔山羊伪鼻疽伯氏菌感染的诊治

伪鼻疽伯氏菌(B.pseudomallei)又名类鼻疽假单胞菌或伪鼻疽杆菌,是人和动物类鼻疽病的病原。自然情况下不但可感染绵羊、山羊、猪、牛、马、驴、骡、犬、猫、兔等多种家畜,家鼠及野生啮齿动物,人     

类鼻疽杆菌碳源利用的探讨

为探讨我国类鼻疽杆菌阿拉伯糖生物型问题，我们应用常规技术对该菌利用碳源的总体情况进行了分析。结果表明，类鼻疽杆菌利用葡萄糖的能力高于果糖，甘露糖和半乳糖（P＜0．05），而绝对不利用山梨糖和鼠李糖，该菌利用双糖中的α－乳糖，麦芽糖，纤维二的能务经较一致（P＞0．05），利用蔗糖的能力较低（P＜0．01），绝对不利用蕈糖和木密糖，几乎所有的类鼻疽杆菌可利用多糖中的糊精，部分菌株可利用淀粉，无菌株利用棉子糖和菊糖，类鼻疽杆菌绝对不利用醇类，如甘露醇，山梨醇，卫予醇，肌醇和糖苷如七叶苷，水杨苷等，但是可以利用所有的氨基酸，从以上的结果可以看出，类鼻疽杆菌似乎只具备α－1，4糖苷键和β－1，4－糖苷键酶，而不具备α－1，6糖苷键或少有α－1，2糖苷键酶。对戊糖的利用总体比较弱，在L－阿拉伯糖的利用中未发现我国菌株存在Ara^ 和Ara^-生物型现象（P＞0．05）。     

人多形核白细胞杀灭类鼻疽杆菌的电镜观察

将类鼻疽杆菌纯培养物加入入脱纤血液中，置37℃水浴中模仿菌血症条件，分离含菌多形核白细胞（PMN）并进行电镜观察，结果表明，细菌吞入期其形态完整，吞噬全和菌体大小一致，随着杀灭功能的进行，天噬体变得很大，其内的细菌呈松散状，形态结构发生很大改变，可杀灭作用的后期，于吞噬全内仅见残留的细菌碎片，由此说明，健康入PMN非但不是类鼻疽杆菌潜藏的场所，而且能将其杀灭。     

用单克隆抗体对鼻疽杆菌和类鼻疽杆菌表面抗原的免疫印迹分析

对鼻疽杆菌M27株与类鼻疽杆菌H4、H103、H146、H152株超声波粉碎后的可溶性抗原作了SDS—PAGE和免疫印迹分析.结果表明,鼻疽杆菌和类鼻疽杆菌特异性MCAb 2D_4与所有实验菌株都有反应,在M27、H4、H103、H146、H152中都有1条分子量为107000的抗原蛋白带,为鼻疽杆菌和类鼻疽杆菌共同抗原带;而类鼻疽杆菌特异性McAb 3A_1只与类鼻疽杆菌H4、H103、H146、H152,分子量为28000的类鼻疽杆菌特异抗原带起反应,不与鼻疽杆菌的抗原带反应.尽管SDS—PAGE中显示M27与H4有多条分子量相同条带,但缺少3A_1对应的特异蛋白带.     

应用单克隆抗体鉴别鼻疽和类鼻疽血清抗体的研究

应用淋巴细胞杂交瘤技术制备了2个类鼻疽菌的McAbs。特异性实验结果表明,这些McAb仅同类鼻疽菌反应,而与包括鼻疽菌在内的其它细菌不发生反应。应用其中的一个McAb—3Al,以ELISA抑制试验检测了49份鼻疽血清和16份类鼻疽血清,结果发现,McAb 3Al的类似抗体是类鼻疽血清的特异性抗体,以此可使两病的血清学诊断得到明确的鉴别。     

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.     

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.     

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

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

Tropical Animal Health and Production -