兔艾美耳球虫分子生物学鉴定技术研究进展

感染兔的艾美耳属球虫主要有11种,其对世界养兔业的危害日益严重。论文综述了国内外兔艾美耳球虫分子生物学鉴定技术的研究进展,基于不同靶标序列分类总结和分析了鉴定技术的优点和存在的问题,展望了未来兔艾美耳球虫分子生物学鉴定技术的应用前景和发展趋势,以期为兔艾美耳球虫病的诊断、预防和控制提供技术手段和方法依据。     

鸡球虫分子检测及遗传变异的研究进展

鸡球虫病是由艾美耳球虫所引起的一种呈世界性分布的寄生原虫病,给世界养禽业造成巨大的经济损失.传统的病原检测方法费时且不够稳定.近年来,新的分子技术不仅为鸡球虫病的诊断提供了快速、灵敏、特异、稳定的检测方法,而且以其为基础可用来建立可靠的种、株鉴定及耐药株与敏感株间差异分析的方法,为球虫群体生物学、流行病学、疫苗研究及遗传变异和耐药机制的相关研究等提供了重要手段.本文对鸡球虫分子检测技术和遗传变异方面的最新研究进展作一概述.     

畜禽球虫生物学与球虫病防治研究——记上海兽医研究所四十年研究回顾

为全面了解中国农业科学院上海兽医研究所(原中国农业科学院上海家畜寄生虫病研究所、中国农业科学院上海家畜血吸虫病研究所)在畜禽球虫生物学与球虫病防治研究方面取得的进展,本文从球虫的流行病学调查、虫种分离鉴定、诊断技术、药物防治、抗药性检测、免疫预防、体外培养、分子生物学等方面,介绍了上海兽医研究所近40年开展的主要工作和取得的研究结果,并提出了今后的重点研究方向。     

鸡艾美耳球虫哈尔滨株的分离与鉴定

为研究鸡艾美耳球虫哈尔滨株单一虫种的生物学特性,本研究利用单卵囊分离技术分离了6种鸡艾美耳球虫哈尔滨株,用分离的单卵囊接种雏鸡,同时应用PCR方法对收集的单卵囊分离株进行球虫种类鉴定并进行同源性和系统进化分析.结果显示,分离得到的6株鸡艾美耳球虫分别为柔嫩艾美耳球虫、毒害艾美耳球虫、堆型艾美耳球虫、早熟艾美耳球虫、和缓艾美耳球虫和布氏艾美耳球虫,PCR结果表明单卵囊分离株确为该6种纯株.本研究表明毛细吸管单卵囊分离法简便易行,使接种难度降低,提高了接种成功率,为球虫的分子生物学研究奠定了基础.     

猪支原体肺炎流行病学和诊断技术研究进展

论文概述了猪支原体肺炎的病原学特性、流行病学和诊断方法的研究进展,并对猪支原体肺炎临床检测、血清学检测、分子生物学检测等检测技术的优缺点进行比较.在猪支原体肺炎预防控制方面,对上述检测技术和诊断方法的应用进行了讨论和展望,旨在为研究该病提供理论参考.     

多重PCR检测3种鸡球虫方法的建立

根据GenBank中发表的巨型艾美耳球虫、柔嫩艾美耳球虫和堆型艾美耳球虫TS-1序列,设计了3对引物,建立了这3种球虫的单一PCR和多重PCR检测方法,并分别对单一PCR和多重PCR方法的特异性和敏感性进行了研究,对巨型艾美耳球虫、柔嫩艾美耳球虫和堆型艾美耳球虫的混合卵囊进行了初步应用.结果显示:单一PCR和多重PCR均能扩增出巨型艾美耳球虫、柔嫩艾美耳球虫和堆型艾美耳球虫特异性条带,其大小分别为151 bp、463 bp、303 bp,其最小检测浓度为0.5ng,对水牛梭形肉孢子虫、有毒艾美耳球虫、猪源弓形虫汤山株及其田间分离株均不起反应,表明建立的方法具有很强的特异性和较高的敏感性,可望用于巨型艾美耳球虫、柔嫩艾美耳球虫和堆型艾美耳球虫的诊断和田间种类调查.     

猪细小病毒病诊断技术研究进展

从传统的病毒分离技术、血清学检测技术以及分子生物学诊断技术等方面对猪细小病毒病诊断技术进行综述,对分子生物学诊断技术进行了重点介绍,并对猪细小病毒病诊断技术进行了展望。     

蹄疫诊断技术研究进展

口蹄疫是偶蹄动物的一种急性、热性、高度接触性传染病,可使世界范围内的畜牧业遭受严重的经济损失,及时准确的诊断是防制口蹄疫的重要环节.诊断口蹄疫的方法可分为临床诊断、生物学实验、血清学诊断、分子生物学检测技术及环介导等五类技术,每类技术中又包括数个具体技术.论文对其优缺点进行比较,并对口蹄疫诊断技术研究进行了展望.     

马梨形虫病诊断技术研究现状

近年来马梨形虫病流行呈上升趋势,对马属动物产业的发展造成了极大的危害.因此,建立一种实时有效的检测方法就显得尤为重要.病原学诊断法、免疫学诊断法、分子生物学诊断方法的相继建立,为马梨形虫病的早期诊断提供了必要的手段.近年来单克隆抗体技术,DNA重组技术的应用,为该病的诊断提供了新的方法.     

动物源性食品中抗球虫药物残留的色谱和质谱检测技术研究进展

综述了常用抗球虫药在动物源性食品中的残留检测方法,主要对液相色谱法、液相色谱质谱联用法、气相色谱质谱联用法等进行了简单的介绍,分析了各种色谱和质谱检测方法的优缺点,并对各种抗球虫药物残留的色谱和质谱检测方法的发展趋势进行了展望,为我国动物源性食品中抗球虫药物的色谱质谱检测技术提供理论依据。     

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 -