牛血红蛋白多态性的研究及应用

本文系统地阐述了国内外有关牛血红蛋白多态性的研究现状。通过对瘤牛、普通牛及其杂种牛血红蛋白基因频率的综合分析,探讨了血红蛋白多态性与家牛品种起源和形成的相关关系;分析了血红蛋白多态性与家牛生产性能间的关系,为家牛的育种工作提供了有关血红蛋白研究的一系列参考材料。     

中国地方品种牛血液同工酶遗传多样性研究进展

本文综述了中国地方黄牛和水牛品种的血液同工酶遗传多样性的研究现状及其在牛遗传育种中的应用。     

猪血液同工酶遗传多态性的研究应用进展

血液同工酶遗传多态性属于生化遗传标记的范畴，通过标记辅助选择，实现早期选种。综述了LDH同工酶、AKP同工酶、ES同工酶、AMY同工酶四种血液同工酶遗传多态性的研究进展及其在猪遗传育种中的应用，旨在为猪遗传育种工作者提供一些理论资料，并探讨了该领域今后的研究方向。     

中国峨边花牛血红蛋白多态性的研究

家畜血液蛋白多态性的研究已在国内外广泛进行。特别是在品种间亲缘关系的研究中,血液蛋白多态性,可直接反映各品种种质的特征。可以了解品种的遗传结构、起源和分化。分布于我国四川省凉山彝族自治州的峨边花牛,目前仅有体型、外貌方面的描述,从遗传学上对血液蛋白多态性的研究,迄今未见报道。本文对峨边花牛Hb进行了测定,     

南阳牛分子标记研究进展

分子标记技术的开发利用在家畜育种中起着越来越重要的作用.南阳黄牛是中国地方良种黄牛之一.近些年来,已在DNA水平上对南阳牛进行了大量的研究,涉及到南阳牛的分子群体遗传特征及起源进化、经济性状分子遗传标记及相关功能基因多态性研究等.本文对南阳牛分子标记研究方面的成就作了综述,以便促进南阳牛的保护、利用和发展.使传统育种和分子标记辅助选择相结合,推动了南阳牛的育种进程.     

血液蛋白多态性在牛种质特征研究中的应用

血液蛋白多态性是遗传基因的表现型，其基因型特征，基因频率特征可以作为牛品种的特征性标志，可以用来追溯牛品种的起源，明确不同牛品种之间的亲缘关系。同时，血液蛋白多态性特征与牛的其它牛特征，如：生产性能，适应性等都有相关。     

柞蚕血淋巴酯酶同工酶的初步研究

用聚丙烯酰胺凝胶电泳的方法对柞蚕血淋巴酯酶同工酶进行了初步的研究 ,结果表明 :柞蚕血淋巴酯酶同工酶酶谱雌雄间无明显差异 ;柞蚕血淋巴酯酶同工酶活性较低 ;不同品种之间酯酶同工酶电泳酶谱差异较大 ,表现出良好的多态性。     

平凉红牛生长性状及胴体性状育种值预计趋势研究

为开展平凉红牛生长性状与胴体性状育种值预计趋势研究，本实验以296头平凉红牛（274头母牛、22头公牛）的育种值预计趋势数据为基础，与美国主要肉牛品种育种值预计趋势进行对比，并开展生长性状与胴体性状间相关性分析，绘制生长性状与胴体性状标准化评分雷达图。研究结果显示，平凉红牛RFI、ADG、WWT、YWT育种值的遗传趋势较安格斯牛、利木赞牛及西门塔尔牛逊色，即各项生长性状的发育较其他品种肉牛慢；平凉红牛Marb、Fat育种值的预计趋势评分高于利木赞牛，但较安格斯与西门塔尔牛低；REA育种值的预计趋势评分较安格斯、西门塔尔及利木赞牛高；HCW育种值的预计趋势评分较安格斯、西门塔尔及利木赞牛低；生长性状中除RFI与胴体性状育种值预计趋势呈一定程度的负相关外，其余指标与胴体性状均呈正相关。本实验研究结果表明，平凉红牛与其他品种肉牛相比，在胴体性状特别是眼肌面积方面表现优秀，因此今后平凉红牛选育工作重点可放在高档肉培育方面。     

柞蚕酯酶同工酶的研究

应用聚丙烯酰胺凝胶电泳方法,调查了柞蚕酯酶同工酶在幼虫不同发育时期、不同组织器官及不同品种间的特异性变化:柞蚕酯酶同工酶活性和酶带数在幼虫不同发育时期存在一定的差异性,各龄盛食期酶带数目多且活性强,其表达与幼虫的生长发育有关;幼虫不同组织器官中酯酶同工酶的活性及种类差异很大,在脂肪体及中肠组织中活性较强,并且种类较多,酶活性的高低与组织的功能关系密切;酯酶同工酶在柞蚕品种间表现出很强的特异性,但在迁移率0.65处各品种均有1条共有谱带。UPGMA法聚类分析显示:33个柞蚕品种可分为4个大的类群,各品种与其母系亲本更多地表现出较近的亲缘关系,说明母系亲本在柞蚕杂交分离育种中起着决定性作用,所以杂交育种应优先注重对母系亲本性状的选择;部分品种在系统分离育种过程中来自亲本的一些性状逐渐弱化,而某一特定性状得到加强,与其亲本间表现出较远的亲缘关系。     

线粒体DNA多态性与家畜遗传育种

在线粒体DNA的特点及其限制性片段长度多态性的基础上，阐明了线粒体DNA多态性在家畜育种上的应用。并指出线粒体DNA多态分析在家畜品种资源研究中的意义。     

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.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

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