我国6个绵(山)羊群体遗传分化的微卫星分析

为进一步了解我国绵(山)羊群体的品种特性及其遗传分化,本文利用微卫星标记对我国6个绵(山)羊群体遗传分化进行了分析。采用中心产区典型群随机抽样方法用聚丙烯酰胺凝胶电泳检测乌珠穆沁羊7个微卫星位点,并引用同实验室小尾寒羊、滩羊、湖羊、同羊、长江三角洲白山羊(参照群体)的相关资料进行群体遗传分化水平分析。研究表明:7个微卫星位点在乌珠穆沁羊、小尾寒羊、滩羊、湖羊、同羊、山羊这6个品种中均存在遗传多态性,各座位等位基因均较丰富。根据标准遗传距离、DA遗传距离以及模糊相容关系进行聚类分析,湖羊与同羊首先聚为一类,乌珠穆沁羊和小尾寒羊聚为一类,然后与滩羊聚为一类,5个绵羊品种最后与山羊相聚。     

长江三角洲白山羊群体遗传结构研究

应用结构基因座和微卫星DNA两种遗传标记探讨长江三角洲白山羊群体遗传结构。结果表明,检测的9个结构基因座位上7个存在多态性,座位的基因平均杂合度、多态信息含量及有效等位基因数分别为0.1767、0.1457和1.2837;7个微卫星位点上共检测到110个等位基因,位点的基因平均杂合度、多态信息含量及有效等位基因数分别为0.8867、0.8774和11.2907。群体内的遗传变异程度相对较高,反映出丰富的遗传多样性,而且微卫星DNA标记揭示的遗传变异高于结构基因座。     

长江中下游以及东南沿海的7个山羊群体的遗传多样性分析

利用23个微卫星标记对宜昌白山羊、马头山羊、湘东黑山羊、福清山羊、戴云山羊、黄淮山羊、长江三角洲白山羊等7个山羊群体进行了遗传多样性检测,结果显示:23个基因座中21个座位在所有群体中都具有多态性,基因座BM0203在各个群体中分别为纯合基因座,但存在群体间变异,基因座BM6444在湘东黑山羊、宜昌白山羊群体中为单态,但在其他群体都存在多个等位基因。总群体基因杂合度为0.819 0,7个群体PIC平均值在0.630 5~0.691 9之间。根据Nei氏遗传距离用UPGMA方法对7个群体进行亲缘关系聚类,马头山羊和湘东黑山羊首先聚为一类,福清山羊、戴云山羊、长江三角洲白山羊、黄淮山羊再和前者依次聚类,最后,宜昌白山羊和它们整个聚为一类。     

长江三角洲白山羊群体遗传结构研究

应用结构基因座和微卫星DNA两种遗传标记探讨长江三角洲白山羊群体遗传结构。结果表明，检测的9个结构基因座位上7个存在多态性，座位的基因平均杂合度、多态信息含量及有效等位基因数分别为0．1767、0．1457和1．2837；7个微卫星位点上共检测到110个等位基因，位点的基因平均杂合度、多态信息含量及有效等位基因数分别为0．8867、0．8774和11．2907。群体内的遗传变异程度相对较高，反映出丰富的遗传多样性，而且微卫星DNA标记揭示的遗传变异高于结构基因座。     

用5个微卫星标记分析四川7个地方山羊品种的遗传关系

选用5个微卫星标记对四川7个地方山羊品种(类群)进行了遗传关系分析。结果表明:5个微卫星标记检测到的等位基因数从1～7个不等,平均多态信息含量为0.537～0.716,其中ILSTS004、ILSTS030、McM038和OarFCB011这4个基因座位为高度多态性基因座,CSSM004为中度多态基因座,都能较好地用于山羊群体间的遗传多样性分析。7个山羊群体的平均多态信息含量为0.601～0.696,群体平均杂合度为0.530～0.655,群体间的遗传分化系数为0.1167,表明7个地方山羊群体的遗传多样性较为丰富。群体间的Nei氏遗传距离为0.0822～0.7240,以Nei氏遗传距离为基础构建的系统聚类树表明,藏山羊、建昌黑山羊、成都麻羊和北川白山羊聚为一大类,第2类为乐至黑山羊和金堂黑山羊,最后简阳大耳羊单独成一类。     

利用微卫星标记对六个羊群体性的研究

采用中心产区典型群随机抽样方法采集了67只洼地绵羊样品,并用PCR-PAGE电泳技术检测了其7个微卫星位点(oarFCB11,oarFCB128,oarFCB48,oarFCB304,MAF33,MAF70和oarAE101)的遗传多态性,同时引用了小尾寒羊、滩羊、湖羊、同羊及长江三角洲白山羊(参照群体)相同资料进行群体遗传关系分析。研究结果表明:7个微卫星标记在洼地绵羊、小尾寒羊、滩羊、湖羊、同羊及长江三角洲白山羊6个品种中均存在多态性,可以用于绵羊群体遗传多样性的评估;7个微卫星标记在6个群体中的多态信息含量、平均有效等位基因数和平均杂合度分别为0.9182、13.9839、0.9511、0.9250、14.5013、0.9579、0.9157、12.9416、0.9446、0.9249、15.1723、0.9639、0.8835、10.0377、0.9333、0.8880、12.5156、0.9550、0.9078、12.1543、0.9389,其中oarFCB304遗传变异最大,oarAE101最小;6个绵(山)羊群体中小尾寒羊和洼地羊的遗传变异较大,对照群体(山羊)最小。通过计算DA距离和DS标准遗传距离,采用非加权配对算术平均法(UPGMA)绘制聚类图,得出洼地羊先和小尾寒羊聚为一类,然后和滩羊合并为一类;同时湖羊和同羊聚为一类;绵羊五个品种为一类后与山羊合并为一类。     

利用微卫星标记对六个羊群体性的研究

采用中心产区典型群随机抽样方法采集了67只洼地绵羊样品，并用PCR—PAGE电泳技术检测了其7个微卫星位点（oarFCB11，oarFCB128，oarFCB48，oarFCB304，MAF33，MAF70和oarAEl01）的遗传多态性，同时引用了小尾寒羊、滩羊、湖羊、同羊及长江三角洲白山羊（参照群体）相同资料进行群体遗传关系分析。研究结果表明：7个微卫星标记在洼地绵羊、小尾寒羊、滩羊、湖羊、同羊及长江三角洲白山羊6个品种中均存在多态性，可以用于绵羊群体遗传多样性的评估；7个微卫星标记在6个群体中的多态信息含量、平均有效等位基因数和平均杂合度分别为0．9182、13．9839、0．9511、0．9250、14．5013、0．9579、0．9157、12．9416、0．9446，0．9249，15．1723，0．9639，0．8835，10.0377，0.9333，0.8880，12.5156，0.9550，0.9078、12．1543、0．9389，其中oarFCB304遗传变异最大，oarAEl01最小；6个绵（山）羊群体中小尾寒羊和洼地羊的遗传变异较大，对照群体（山羊）最小。通过计算DA距离和DS标准遗传距离，采用非加权配对算术平均法（UPGMA）绘制聚类图，得出洼地羊先和小尾寒羊聚为一类，然后和滩羊合并为一类；同时湖羊和同羊聚为一类；绵羊五个品种为一类后与山羊合并为一类。     

利用微卫星标记分析云南省10个山羊品种的遗传多样性

本研究应用微卫星标记技术,选取15个微卫星位点分析云南省10个地方山羊品种(弥勒红骨山羊、圭山山羊、马关无角山羊、师宗黑山羊、威信白山羊、龙陵黄山羊、罗平黄山羊、云岭山羊、宁蒗黑头山羊、昭通山羊)以及参照群波尔山羊的遗传多样性及遗传关系。结果表明:除MCM200外,其他14个微卫星位点均属于高度多态位点;11个群体观测杂合度值(0.573～0.692)、期望杂合度值(0.608～0.696)、平均多态信息含量(0.562～0.655)均大于0.5,表明群体遗传多样性丰富;群体间遗传变异系数为0.112,处于中等以下分化程度,群体近交系数均为正值(除马关无角山羊),表明云南省地方山羊品种内都存在不同程度的近交;群体间的基因流大于1,说明品种间存在着一定程度的基因交流;基于Nei氏遗传距离计算和UPGMA聚类分析,波尔山羊与10个云南地方山羊品种亲缘关系较远,单独为一支;10个云南地方山羊品种分为2个类群,弥勒红骨山羊、圭山山羊和马关无角山羊聚为一支,师宗黑山羊、威信白山羊、龙陵黄山羊、罗平黄山羊、云岭山羊、宁蒗黑头山羊、昭通山羊聚为一支。     

贵州地方山羊品种遗传背景的微卫星分析

用15个牛微卫星位点,以波尔山羊为对照,研究了4个贵州地方山羊品种(贵州白山羊、贵州黑山羊、黔北麻羊、榕江小香羊)的遗传背景。结果:可分析的多态位点6个(BM1258、D1S104、ILSTS030、INRA063、INRABERN192、RM088),占40%(6/15),反应了牛微卫星位点与山羊有较高同源性;贵州地方山羊品种比波尔山羊具有较高的遗传多样性,高低顺序是贵州白山羊>贵州黑山羊>黔北麻羊>榕江小香羊>波尔山羊;群体遗传分化大,群体变异主要存在于品种内,而品种间的变异较小;贵州白山羊与贵州黑山羊遗传距离最近,其次是榕江小香羊、黔北麻羊,与波尔山羊遗传距离最远,这与它们的地理分布及品种形成相符。     

微卫星DNA标记在三个山羊品种中的遗传多态性研究

利用四个微卫星标记对波尔山羊、太行山羊和河北奶山羊的等位基因频率、群体多态信息含量、有效等位基因数和杂合度进行了遗传检测。结果表明：四个微卫星位点在波尔山羊、太行山羊和河北奶山羊三个品种中存在多态性。可以用于山羊遗传多样性的评估；位点OarFCB11变异最大，位点MCM38变异最小，从不同品种来看，太行山羊的遗传变异程度最大，而波尔山羊的遗传变异程度相对较小。     

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 Prevalence and Intensity of Helminth and Coccidial Infections in Dairy Cattle in Central Kenya

A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.     

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.     

Hypothalamic dopamine is required for salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the relationship between hypothalamic dopamine (DA) and salsolinol (SAL) for the secretion of prolactin (PRL) in goats. SAL or thyrotropin‐releasing hormone (TRH) was intravenously injected into female goats treated with or without the D₂ DA receptor antagonist haloperidol (Hal), which crosses the blood‐brain barrier, and the PRL‐releasing response to SAL was compared with that to TRH. PRL‐releasing responses to SAL, Hal, and Hal plus SAL were also examined after a pretreatment to augment central DA using carbidopa (Carbi) and L‐dopa. The PRL‐releasing response to Hal alone was greater than that to SAL or TRH alone. The PRL‐releasing response to Hal plus SAL was similar to that of Hal alone. In contrast, the PRL‐releasing response to Hal plus TRH was greater than that to TRH or Hal alone. The treatment with Carbi plus L‐dopa inhibited SAL‐ and Hal‐induced PRL secretion. The inhibition of the PRL‐releasing response to SAL disappeared when SAL was injected with Hal. These results indicate that the mechanisms underlying the SAL‐induced PRL response differ from those of TRH, and suggest that hypothalamic DA and its synthesis is associated in part with SAL‐induced PRL secretion in goats.     

Laboratory diagnosis of respiratory diseases of cattle

The authors describe the procedure of laboratory diagnosis for bovine respiratory diseases: direct diagnosis by isolation and for identification of bacteria or viruses and indirect diagnosis by serological methods. They specify the restraints and limits of this diagnosis and the significance results which are obtained and connected with knowledge of anamnestic information.     

The effect of peri-parturient anthelmintic treatment on the productivity of dairy cattle in subtropical western India

Trials with fenbendazole (Panacur, Hoechst India Ltd) were carried out on two commercial farms in subtropical western India to study the response and economics of nematode treatment in adult dairy cows. Milk yield, lactation length, time to first oestrus and worm egg output were monitored in treated and control groups. Treatment reduced the egg count considerably. Treated cows produced 142 litres more milk over 100 days (p<0.05), with extension of lactation length and advancement of time to first oestrus. The economic gain in terms of milk yield far outweighed the cost of anthelmintic used.     

An Evaluation of the Acceptability as Forage of Some Nutritive and Antinutritive Components and of the Dry Matter Degradation Profiles of Five Species of Ficus

The suitability of five species of Ficus, F. mucoso, F. thonningii, F. polita, F. religiosa and F. benjamina, for feeding ruminant livestock was studied. The nutritive and antinutritive components were determined and the acceptability of the forages to livestock was assessed using a cafeteria method in 8 adult small ruminants. Also, the degradation potential of the dry matter of the five Ficus species was investigated using 3 fistulated sheep. The crude protein (CP) content of the Ficus species varied significantly (p < 0.05), ranging from 130 to 180 g/kg DM. The content of neutral detergent fibre (NDF) also varied significantly (p < 0.05), ranging from 650 to 710 g/kg DM. The organic matter (OM) contents did not differ significantly (p > 0.05), having a mean value of 916 g/kg DM. The concentrations of tannin, saponin, phytic acid and oxalic acid were low. The acceptability of the forage was similar for four of the species but poor for F. polita. The extent of DM degradation varied significant among the Ficus species, the ranking order being F. benjamina > F. thonningii > F. mucoso > F. religiosa > F. polita.