普通奥斯特线虫和叶氏夏伯特线虫体外阶段发育及形态学的比较研究

虫卵的检查虽然是蠕虫病的主要生前诊断方法，但大多数线虫的虫卵形态均较相似，特别是普通奥斯特线虫和夏件特线虫的虫卵，据一般资料图版记载难以区分，并且虫卵的量度不一。试通过体外阶段发育试验的研究，从虫卵的形态及发育时间，形态学变化和幼虫的形态区别上，得出其具有诊断意义的差异特点。     

羊消化道4种易混淆线虫虫卵的形态学观察与比较

为了方便临床上鉴定羊消化道常见且易混淆线虫虫卵并丰富相关资料,试验从羊消化道中采集疑似捻转血矛线虫、夏伯特线虫、食道口线虫和奥斯特线虫共4种线虫,采用形态学和分子生物学方法鉴定虫种,将4种线虫于体外短暂培养后得到纯种虫卵,通过观察虫卵不同发育阶段的胚胎形态变化获取每种线虫虫卵形态特征,并对虫卵的长径、宽径和长宽比进行测定。结果表明：经鉴定4种线虫分别为捻转血矛线虫、绵羊夏伯特线虫、粗纹食道口线虫和普通奥斯特线虫。4种线虫虫卵初期胚胎多呈收缩状态且形似桑葚,在外观形态上具有相似性,均为双层卵壳,多数对称,少数不对称。捻转血矛线虫虫卵呈短椭圆形,颜色较浅;绵羊夏伯特线虫虫卵呈椭圆形,颜色较捻转血矛线虫虫卵深;粗纹食道口线虫虫卵呈长椭圆形,颜色较捻转血矛线虫虫卵深,与绵羊夏伯特线虫虫卵相近;普通奥斯特线虫虫卵亦呈长椭圆形,颜色与捻转血矛线虫相近,较绵羊夏伯特线虫和粗纹食道口线虫虫卵浅。虫卵在生理盐水中培养1～6 d后,捻转血矛线虫、绵羊夏伯特线虫和普通奥斯特线虫依次进入蝌蚪期和幼虫期,但仅凭肉眼依然难以区分虫卵种类;绵羊食道口线虫未观察到含蝌蚪或含幼虫的虫卵,仅在桑葚期观察到胚胎收缩成1团及...     

山东省菏泽市部分散养济宁青山羊肠道寄生虫检测

为了解山东省菏泽市散养济宁青山羊肠道寄生虫感染情况,采集3家济宁青山羊散养户的32份新鲜粪便,用离心沉淀法、饱和盐水漂浮法以及显微镜测微尺测定法进行虫卵检测。结果显示:共检测到10种虫卵,初步诊断为前后盘吸虫卵、歧腔吸虫卵、毛圆线虫卵、夏伯特线虫卵、食道口线虫卵、马歇尔线虫卵、捻转血矛线虫卵、细颈线虫卵、奥斯特线虫卵和艾美耳球虫卵囊;散养济宁青山羊肠道寄生虫感染率为100%,其中以线虫和球虫感染为主,并且多种寄生虫混合感染较为普遍。结果表明,菏泽市散养济宁青山羊寄生虫感染较为普遍,提示散养户应积极做好济宁青山羊肠道寄生虫驱虫工作。     

祁连地区牦牛主要消化道线虫对伊维菌素的抗药性检测

为检测祁连地区牦牛自然感染的主要消化道线虫对伊维菌素的抗药性,采用粪便虫卵减少试验,选取60头自然感染消化道线虫的试验牦牛,随机分为4组,1-3组分别按0.1 mg/kg、0.2 mg/kg、0.3mg/kg.b w剂量口服伊维菌素片剂,4组为阳性对照组。在给药前1 d、给药后7 d和14 d,检查统计给药后虫卵减少率,进行抗药性评价。结果表明：给药后7 d和14 d, 0.1 mg/kg剂量组对奥斯特线虫虫卵减少率分别为96.7%和98.1%,对马歇尔线虫、细颈线虫的虫卵减少率均为100%;0.2 mg/kg剂量组及0.3 mg/kg剂量组对奥斯特线虫、马歇尔线虫、细颈线虫的虫卵减少率均为100%。试验证明祁连地区牦牛主要消化道线虫对伊维菌素尚未产生抗药性。     

大理州部分地区山羊消化道寄生虫感染情况调查

为了获悉大理州部分地区山羊消化道寄生虫感染情况,对送检山羊粪便进行虫卵检测。结果表明,山羊寄生虫总体感染率为82.4%,共检出乳突类圆线虫、奥斯特线虫、球虫和蛔虫4种寄生虫。     

Rintal片驱除绵羊消化道线虫的试验

用Ｒｉｎｔａｌ片进行了驱除绵羊消化道线虫试验。结果表明当５ｍｇ／ｋｇ体重剂量时对捻转血矛线虫、哥伦比亚线虫、羊仰口线虫、细预属线虫和奥斯特线虫等绵羊消化道线虫的虫卵减少率,虫卵转阴率、虫卵孵化第三期幼虫减少率和第三期幼虫转阴率均可达到１００％,且安全,无任何毒副作用。     

Rintal颗粒剂对绵羊消化道寄生虫的驱虫效果试验

用Rintal颗粒剂对绵羊进行了消化道线虫驱虫试验。结果表明当前剂量为5.0mg/kg体重时,Rintal颗粒剂对绵羊食道口线虫、细颈属线虫、毛圆线虫、夏伯特线虫、奥斯特线虫以及肺丝虫等虫卵减少率,虫卵转阴率、虫卵孵化第3期幼虫减少率和第3期幼虫转阴率均为100%,而且安全,使用方便,易于保管运输。     

祁连地区牦牛主要消化道线虫对阿苯达唑的抗药性检测

为了解牦牛主要消化道线虫对阿苯达唑的抗药性,采用粪便虫卵减少试验,将60头供试牛随机分为4组,每组15头。1～3组为试验组,第4组为阳性对照组。按照分组对试验牛逐头称重、编号、记录,1～3组分别按5、10、15mg/kg体重剂量经口投服阿苯达唑片剂,第4组给予安慰剂。给药前1d,给药后7d和14d各组试验牛逐头直肠采粪,采用饱和盐水漂浮法进行实验室检查,统计消化道线虫1g粪便中的虫卵数(EPG)。根据投药后7d和14d EPG的变化情况,奥斯特线虫7d的虫卵减少率为86.5%,90.4%,100%,14d的虫卵减少率为89.2%,93.8%,97.0%;马歇尔线虫7d的虫卵减少率为73.1%,96.2%,94.5%,14d的虫卵减少率为84.9%,98.0%,100%;细颈线虫7d的虫卵减少率为83.2%,90.4%,93.8%,14d的虫卵减少率为81.5%,93.3%,95.1%。结论:根据世界兽医寄生虫学促进协会(WAAVP)推荐的虫卵减少百分率95%置信域来判定虫体是否产生了抗药性,得出奥斯特线虫、细颈线虫和马歇尔线虫对阿苯达唑均未产生抗药性。     

养殖场绵羊寄生虫病的控制技术

采用粪便寄生虫虫卵检测和虫体鉴定方法调查四川凉山半细毛羊原种场及周围的羊寄生虫，主要有血矛线虫、奥斯特线虫、仰口线虫、夏伯特线虫、食道口线虫、毛首线虫、肺线虫、细颈线虫、片形吸虫、前后盘吸虫。根据凉山州半细毛羊原种场的主要寄生虫发育史、流行病学和中间宿主及该地的气候等制订寄生虫痛的定期监测程序，即每年的2、5、8、11月各进行一次监测；根据该场主要寄生虫痛疫情、绵羊的抵抗能力等制订进行预防性驱虫的参考标准，即15％羊的片形吸虫虫卵EPG值大于300时或20％羊的线虫虫卵EPG值大于1000时进行驱虫；再根据“虫净灵”效果，制订驱虫效果考核参考指标，即口服药物后4d线虫虫卵转阴率95％以上、20d吸虫虫卵转阴率100％。从而建立起“定期监测、按需驱虫、及时评估”的控制技术，实施2年来的结果表明，该场绵羊的主要寄生虫痛即片形吸虫病和线虫病的感染率分别下降了80．51％和27．80％。     

C57BL/6小鼠肠道线虫的分离与鉴定

对某一实验动物养殖场出现大规模消瘦、生长发育不良的C57BL/6小鼠进行诊断。利用饱和生理盐水漂浮法对粪便虫卵进行检测,对小鼠进行剖检,并对不同肠段发现的虫体进行形态学鉴定。为进一步确诊,对发现的不同形态寄生虫分别提取DNA,进行18S rDNA基因片段的扩增、测序、同源比对和进化树分析。根据虫卵及虫体的形态特征,可初步判定从小鼠肠道分离到两种寄生虫,经测序比对进一步确认两种寄生虫分别为隐匿管状线虫和四翼无刺线虫。据形态学观察和分子生物学检测,确诊该起疫情为隐匿管状线虫和四翼无刺线虫混合感染引起。     

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 -