宁夏滩羊体大品系遗传标记的研究

研究首先采用RAPD技术,利用混合基因池(DNA pool)法,对滩羊体大品系、普通品系进行DNA多态性分析。从100种具有10个碱基的随机引物中,筛选出84种引物在滩羊群体基因组中共扩增出358条带,其中22种引物扩增产物表现为多态(占22%),且扩增出32条有差异的条带,占总带数的8．94%(32/358);62种引物的扩增产物表现为单态(占62%)。滩羊体大品系的特异性条带5个,而普通品系的特异性条带7个。这些特异标记可以用来鉴定滩羊的2个品系。滩羊体大品系和普通品系间的遗传距离为0．136±0．087,表明2个品系之间的亲缘关系很近。     

扁蓿豆不同品系ISSR标记遗传差异和遗传多样性

采用ISSR分子标记技术对扁蓿豆4个品系的遗传多样性、遗传差异和遗传结构进行了研究。用7个有效引物对4个品系进行PCR扩增,共获得73个等位基因位点,每条引物平均检测出10.4个位点,其中多态性位点69个,多态位点百分率为94.5%。各品系的Nei’s遗传多样性为0.2569,Shannon’s信息指数为0.4046。Nei’s指数估算和分子方差分析均表明,扁蓿豆4个品系的遗传多样性主要存在于品系内,4个品系间亦出现了较大的遗传分化(Gst=0.1324)。品系00-61、90-36、00-81和93-21的多态位点百分率分别为73.97%、79.45%、82.19%和83.56%;Nei’s遗传多样性(H)分别为0.2050、0.2153、0.2264和0.2474;Shannon’s信息指数(I)分别为0.3222、0.3396、0.3538和0.3821。各品系的遗传参数大小排序均为品系93-21品系00-81品系90-36品系00-61。采用系统聚类和主坐标分析(PCA)两种方法所获得的聚类结果一致,即品系00-61和00-81遗传差异相对较小,其次是品系90-36,品系93-21与各品系的遗传差异较大。     

四川几个山羊品种(群体)与岩羊RAPD分析

以两组40个随机引物，筛选出16个重复性好的多态引物。对四川5个山羊品种、藏山羊两个生态类型、3个杂交群体和岩羊共计113只个体，进行随机扩增多态DNA(RAPD)分析。结果表明：16个引物扩增出67条带，其中54条带呈现多态。多态率为80．60％。山羊各群体共有条带为23条，山羊和岩羊共有条带为13条。岩羊有4条特异带。不同引物所扩增出的片段在各群体中分布频率不同。山羊群体间相似系数为0．8216—0．9362，其中，安哥拉山羊与建昌黑山羊杂交后代F2和F3之间相似系数最大。为0．9362。山羊各群体与岩羊相似系数为0．4996—0．5064。山羊群体间的遗传距离为0．0638—0．1784。山羊各群体与岩羊的遗传距离为0．4936—0．5403。高原型藏山羊与山谷型藏山羊间的遗传距离小(0．1005)、相似系数大(0．8995)。序列为TTCCGAACCC引物扩增出的片段为750bp，仅在高原型藏山羊中出现，可作为区分这两个生态类型的遗传标记。     

利用形态性状以及SSR标记鉴定4个川西北老芒麦品种（系）

基于23个形态性状和SSR分子标记,对在川西北推广应用的老芒麦(Elymus sibiricus)3个国审品种(‘川草2号’、‘阿坝’和‘康巴’)及1个新品系(‘雅江’)进行了鉴定研究。各品种表型性状与遗传背景差异较明显。新品系‘雅江’表现出优良的农艺性状,株高、叶长、叶宽、茎粗等形态性状均值显著优于3个对照品种(P0.05)。13对多态性好、特异性强、条带清晰的SSR引物在4个品种(系)中共扩增出90条条带,其中具有多态性的条带共68条,引物多态性条带比例(PPB)、多态性信息含量(PIC)及Shannon多样性指数(H)的平均值分别为76.32%、0.309及0.451,在供试品种(系)中均表现出较高的多态性。基于形态数据的欧氏距离和基于SSR数据的遗传距离矩阵之间具有较强的相关性(r=0.696,P=0.08),表明联合形态学标记和遗传标记能很好地用于品种鉴定,并且基于形态数据以及SSR分子标记的UPGMA聚类结果基本一致。筛选出4对引物可用于供试品种鉴定,并绘制了DNA指纹图谱。新品系‘雅江’具有明显区别于其它3个主推品种的形态特征和遗传背景,这为川西北高原老芒麦主要品种的遗传关系分析及品种的知识产权保护提供了数据支撑。     

近交系大鼠DNA指纹图与微卫星DNA比较分析

为了建立一种对近交系大鼠遗传物质进行精确可靠、快速简便的监测方法，利用DNA指纹技术对国内6个品系8个近交系大鼠群体进行了DNA多态性的分析，并与PCR扩增微卫星DNA技术进行了比较。其结束显示：(1)不同品系之间DNA指纹图差异较大，同一群体不同个体间DNA指纹图带的相似系数和共有带率除SHR（哈)和WKY(哈)小于0．7外，其他均大于0．9。不同地区同一SHR间和WKY间DNA指纹图也存在差异，相同DNA不同次制作的DNA指纹图谱基本一致。(2)不同品系个体间微卫星DNA具有显著多态性；同一群体不同个体之间除SHR(哈)的SMST位点和WKY(哈)的AGT位点出现一定的差异外，其他均没有差异。DNA指纹图能更精确可靠地反映出动物个体间的遗传背景，而微卫星DNA遗传监测方法比较简便快捷。     

云南东方蜜蜂随机扩增多态DNA研究

本文利用随机扩增多态DNA技术研究了云南东方蜜蜂 (工蜂 ) 32个个体的遗传变异。从 2 5个引物中筛选出 11个引物 ,其中 9个引物扩增出多态谱带。共检测到63条扩增片段 ,其中 46条出现变异。用Nei的片断共享度公式计算了 32个个体的遗传距离 ,用UPGMA聚类法构建了系统发育树状图。系统聚类图中大多数采自同一地区的样本聚在一起 ,但也存在一定的交叉 ,提示地理群体间近期可能存在一定程度的基因流     

河南省4种地方品系鸡的RAPD分析

应用随机扩增多态性DNA(random amplified polymorphic DNA,RAPD) 技术分析河南省4个地方鸡的品系,固始鸡快羽G_K系、固始鸡慢羽G_M系、矮小型绿壳蛋鸡、黄麻羽丝毛乌骨鸡的遗传变异。用186个随机引物对4个鸡种基因组DNA池扩增筛选,40个引物产生多态性。此40个引物经重新优化反应体系后,对120个个体的基因组DNA 进行RAPD分析。40个引物共产生387种扩增片段,扩增产物片段的长度大小在100～2220 bp范围内。利用电泳分析数据分别计算4个品系群体之间的遗传相似系数和遗传距离指数,结果4个鸡种的亲缘关系与它们的引种情况基本一致。同时也证明了RAPD技术可以作为分子标记,很好地检测鸡种群内的遗传变异及区分不同鸡品系。     

四川9个山羊品种(群体)与岩羊RAPD分析

以两组40个随机引物,筛选出16个重复性好的多态引物,对四川9个山羊品种(群体)和岩羊共计113只个体,进行随机扩增多态DNA(RAPD)分析.结果表明16个引物扩增出67条带,其中54条带呈现多态,多态率为80.60%.山羊各群体共有条带为23条,山羊和岩羊共有条带为13条,岩羊有4条特异带.不同引物所扩增出的片段在各群体中分布频率不同.山羊群体间相似系数为0.821 6～0.936 2,其中安哥拉山羊与建昌黑山羊杂交后代F2和F3之间相似系数最大,为0.936 2.山羊各群体与岩羊相似系数为0.499 6～0.506 4.山羊群体间的遗传距离为0.063 8～0.178 4.山羊各群体与岩羊的遗传距离为0.493 6～0.540 3.高原型藏山羊与山谷型藏山羊间的遗传距离小(0.1005)、相似系数大(0.899 5),序列为TTCCGAACCC引物扩增出的片段为750bp,仅在高原型藏山羊中出现,可作为区分这两个生态类型的遗传标记.     

滩羊体大品系遗传标记的研究

本研究首先采用RAPD(Romdom Amplified Polymorphic DNA)技术,利用混合基因池(DNApool)法,对滩羊体大品系、普通品系进行DNA多态性分析.从100种具有10碱基的随机引物中筛选出84种引物可在滩羊群体基因组中得到扩增,共扩增出358条带,其中22种引物扩增产物表现为多态(占22%),且扩增出32条有差异的条带,占总带数的8,94%(32/358);62种引物的扩增产物表现为单态(占62%);另有16种引物扩增非常微弱,不便分析(占16%).根据Nei氏片段共享度公式计算出滩羊的体大品系和普通品系间的遗传距离为0.14±0.25,表明两品系之间的亲缘关系很近.同时在分析过程中发现滩羊体大品系,普通品系均出现了具有品系特征的特异性条带.滩羊普通品系有7条PS-107-550,PS-510-500,PS-512-450,PS-101-450,PS-512-400,PS-511-400,PS-12-370;体大品系有5条PS-509-875,PS-515-875,PS-106-750,PS-1008-700,PS-1010-370;以上引物可作为区分两品系的标记引物,特征性条带可以作为各自的分子标记来进行品系鉴定.     

蛋鸡不同品系随机扩增多态DNA指纹分析

利用随机扩增多态DNA指纹分析技术对星杂288鸡的四个品系和滨白鸡的遗传变异进行比较,从40个引物中筛选出的18个引物对40个个体的核DNA进行多态性分析。共得到184个扩增片段,其中96个片段具有多态性,占52.17％。通过对RAPD图带进行遗传相似度计算和聚类分析,结果表明星杂288的D系与滨白鸡的遗传距离最近,先聚在一起,再依次与B、C、A相聚,这与鸡的品系选育形成相吻合。用RAPD技术分析鸡品系间的遗传变异作为畜禽遗传结构分析的辅助手段是相对可靠的。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

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.     

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.     

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.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

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.