山东境内五个山羊种群生化遗传多态性研究

应用聚丙烯酰胺凝胶电泳法（PAGE）,对山东省境内山羊种群的血液生化遗传标记多态性进行分析。结果表明,所测5个山羊品种中,Tf、Akp及EsⅠ基因座均表现出多态性,Hb和EsⅡ基因座仅分别在崂山奶山羊和莱芜黑山羊品种中表现出多态性,Amy未表现出多态性;平均杂合度为0．2876,基因纯合系数在0．6以上,群体的遗传分化系数为0．02614,说明这些山羊群体的遗传变异较低,其97．386％来自群体内遗传多态现象。基于31个多态位点基因频率的系统发育分析证明,带有共同遗传基础的济宁青山羊、鲁北白山羊和崂山奶山羊遗传距离较近,引进的南非波尔山羊与4个地方山羊品种遗传距离最远。     

重庆本地山羊血清同工酶多态性的研究

采用聚丙烯酰胺凝胶电泳法对重庆地区的板角山羊、川东白山羊和重庆黑山羊的3种血清同工酶多态性进行了研究。结果表明：重庆本地3种山羊的Es基因座存在Es”、Es。两种表型,碱性磷酸酶中出现有带型(AkpB)和无带型(AkpO),其中AkpO占优势;淀粉酶中Amy2存在多态性,整个群体的基因平均杂合度为0．3610,基因分化系数为0．01。由3个品种构建的系统发育树表明重庆黑山羊与板角山羊的亲缘关系较近．与川东白山羊的关系较远。     

波尔山羊和山西省地方山羊品种微卫星DNA多态性分析及群体间杂种优势预测

（方法）利用5个微卫星标记对山西省5个山羊品种遗传多态性进行分析,（目的）以预测波尔山羊与地方山羊品种的杂种优势,为山西省肉用山羊新品种培育及波尔山羊在山西省合理杂交利用提供理论依据。（结果）5个山羊品种共检测到70．0个等位基因,各位点的等位基因数在9．0～21．0之间;经群体遗传统计分析,5个山羊品种平均有效等位基因数4．94～6．05个,平均多态信息含量0．7053～0．7982,平均基因杂合度0．7592～0．8316。5个山羊品种间遗传分化系数0．0607;波尔山羊与吕梁黑山羊的标准遗传距离最大（0．5083）,其余依次为阳城白山羊（0．4474）、洪洞奶山羊（0．4332）、黎城大青羊（0．3301）。（结论）5个微卫星位点均为高度多态位点,可用于5个山羊品种遗传多样性评估;5个山羊品种在5个微卫星位点多态性丰富,遗传变异大,品种间遗传分化小。据品种间遗传距离推测,波尔山羊与吕梁黑山羊的杂种优势最大,与阳城白山羊和洪洞奶山羊的杂种优势次之,与黎城大青羊的杂种优势最小。     

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。     

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。     

山羊品种遗传多样性的分析

利用6个微卫星标记对中西部7个山羊品种(陕南白山羊、陕北白绒山羊、西农萨能羊、关中奶山羊、太行山羊、黄淮山羊、伏牛山羊)共计322个个体进行了遗传多样性检测,并根据Nei氏遗传距离进行了聚类分析。结果表明:6个微卫星标记在这7个品种中存在高度多态性;陕北白绒山羊的遗传变异程度最大,平均杂合度和平均多态信息含量分别为:0.8401和0.8244;而关中奶山羊的遗传变异程度相对较小,平均杂合度和平均多态信息含量分别为:0.7990和0.7784。UPGMA聚类分析表明,黄淮山羊和伏牛山羊聚为一类,陕南白山羊,太行山羊,陕北白绒山羊依次加入,西农萨能羊和关中奶山羊作为一类最后加入。     

云南肉山羊黑色品系遗传结构的微卫星分析

应用微卫星技术对云南肉山羊黑色品系两个群体(石林群体和寻甸群体)、两个育种素材(云岭黑山羊和努比山羊)及对照群(萨能奶山羊)基因组DNA进行了11个微卫星位点多态性分析,以期为云南肉山羊黑色品系的选育提高及开发利用提供依据.结果表明:各群体平均期望杂合度(He)和平均多态信息含量(PIC)均在0.5以上,表明5个研究群体遗传多样性丰富,其中云南肉山羊黑色品系石林群体He和PIC值在5个群体中居最高,表明这个群体遗传多样性最为丰富;遗传分化的研究表明云南肉山羊黑色品系石林群体与寻甸群体之间存在着最大的基因流(Nm=18.981)、最高的遗传一致度(0.906)、最小的遗传分化系数(Fst=0.013)及最小的遗传距离(0.099),UPGMA聚类图也显示二者最后聚为一支,说明二者遗传结构基本一致,可归为同一类群体;UPGMA聚类图还显示云南肉山羊黑色品系两个群体(石林与寻甸)与育种素材努比山羊关系最近,与另一育种素材云岭黑山羊关系稍远,而与对照群萨能奶山羊的关系最远,分属于不同的两个分支.     

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。     

大足黑山羊与周边黑山羊品种(群体)mtDNA D-loop序列多态性研究

本实验旨在研究大足黑山羊与川、渝、滇三地的其他4个黑山羊品种(群体)遗传多样性及聚类关系,采用直接测序法分析了这些山羊品种(群体)的mtDNA D-loop序列多态性。结果表明:5个黑山羊群体的碱基组成没有明显差别;5个黑山羊品种mtDNA D-loop序列多态性较丰富;聚类分析显示,大足黑山羊与渝东黑山羊的遗传距离最近,大足黑山羊与川北黑山羊和乐至黑山羊遗传距离次之,与圭山黑山羊遗传距离最远,这与此5个黑山羊品种地理分布相符。     

云南肉山羊黑色品系遗传结构的微卫星分析

应用微卫星技术对云南肉山羊黑色品系2个群体(石林群体和寻甸群体)、2个育种素材(云岭黑山羊和努比山羊)及对照群(萨能奶山羊)基因组DNA进行11个微卫星位点多态性分析,以期为云南肉山羊黑色品系的选育提高及开发利用提供依据。结果表明:各群体平均期望杂合度(He)和平均多态信息含量(PIC)均在0.5以上,表明5个研究群体遗传多样性丰富,其中云南肉山羊黑色品系石林群体He和PIC值在5个群体中最高;遗传分化的研究表明云南肉山羊黑色品系石林群体与寻甸群体之间存在着最大的基因流(Nm=18.981)、最高的遗传一致度(0.906)、最小的遗传分化系数(Fst=0.013)及最小的遗传距离(0.099);UPGMA聚类图也显示二者最后聚为一支,说明二者遗传结构基本一致,可归为同一类群体;UPGMA聚类图还显示云南肉山羊黑色品系2个群体(石林与寻甸)与育种素材努比山羊关系最近,与另一育种素材云岭黑山羊关系稍远,而与对照群萨能奶山羊的关系最远,分属于不同的2个分支。     

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.     

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     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.