黄牛的胆汁分泌量及与成黄关系的研究

黄牛的胆汁分泌量及与成黄关系的研究马玉忠＊王春王敖李建基尹逊河朱连德（山东农业大学,泰安２７１０１８）７０年代林如忠等在活牛胆囊内培植牛黄获得成功。但所培植的牛黄产量低,质量不稳定。有关牛黄形成的理论还不太明了。为提高培植牛黄的产量和质量及完善牛黄形...     

天然牛黄形成机理探讨

天然牛黄形成机理探讨任成林（河北省张家口农业高等专科学校，０７５１３１）天然牛黄是牛体内胆囊、胆管和肝胆管中的结石，是名贵的中药材。天然牛黄形成率很低，仅在０．１％左右；产量少而医用需求量大，历来供不应求。因此，国内许多单位推广应用在活牛体内培育牛黄...     

牛体外牛黄发生器内成黄机制的研究

利用5头健康黄牛同时施行了牛体外牛黄发生器内培植牛黄手术和肝脏内胆管插管手术，以探讨牛黄的形成机理。研究结果表明：在牛黄菌种的作用下，胆汁的理化特性首先在肝内胆管发生改变，转变为成黄胆汁；胆汁进入胆囊后，黏蛋白含量和细菌的数量迅速增加，结果导致胆汁的黏度升高，胆酸含量和pH值下降，这加速了牛黄小颗粒的形成；在牛黄发生器内，胆汁的黏度和pH值下降，这促进牛黄小颗粒的沉降、聚集和附着，从而减少了牛黄的丢失，提高了牛黄产量。牛的体重大，分泌的胆汁多，牛黄产量高。     

提高人工培植牛黄产量和质量的措施

人工培植牛黄,近年来在国内取得了一定的成果。但普遍存在着两大问题,一是产量不稳定,二是质量上与天然牛黄相比,胆酸含量相似,而胆红素含量不稳定,偏低者居多。其影响因素是多方面的,最日月显的因素是黄床形态和活性、致黄菌的优劣、手术技巧和熟练程度、地区类型、牛的品种及年龄、饲料和饲喂方式等。为提高人工培植牛黄的产量和质量,应根据天然牛黄形成的机理,相应地采取如下措施。     

天然牛黄及活体牛胆汁的生物形态学研究

对不同地区的5枚天然牛黄及37份活体牛胆汁分别做石蜡切片及涂片,经不同染色观察,发现所有被检天然牛黄中均存在密集而纯一的大肠杆菌及大量呈鱼鳞状分层次排列的肝片吸虫虫卵;活体牛胆汁的细菌检出率为56.8%,其中大肠杆茵占89.9%;肝片吸虫虫卵检出率为 66.7%。由此对天然牛黄形成机理进行了分析探讨,摸索出了牛黄切片染色的新方法。     

对形成牛黄的有关内外因素的分析

为探讨影响人工培植牛黄形成的内外在因素,以便为牛体内人工培黄技术的改进、完善提供科学依据,作者通过对天然牛胆石症高发区生态环境调查及牛体内牛黄形成的模拟试验,对影响牛体内牛黄形成的有关内外在因素进行了初步分析。调研结果表明,牛体内牛黄的形成,在很大程度上取决于气候、土壤、水质等生态性因素,菌株宜选用毒力弱的大肠杆菌(EPEC),并加入适当的添加剂。     

活体牛黄的诊断与采集处理技术

牛体牛黄根据其来源可以分为天然牛黄和人工培植牛黄,前者是牛肝胆系统自然形成的病理产物;后者是以外科手术为手段,在牛的胆囊内植入致黄因子,诱发机体形成的。通常情况下,为了减少手术取黄过程中牛黄的损耗,一般提倡屠宰取黄,特别是对老龄牛、残、菜牛或其它利用价值不大的牛,更应如此。但是对生产利用价值比较高的牛,若因胆结石影响使用性能或人培     

牛体外培养牛黄获得成功

河北农业大学郝满良等运用现代胆结石病理学理论,用牛胆汁在培养罐内模拟牛胆囊结石的机理,培养出与天然牛黄具有相似药理作用的牛黄。这种方法打破了牛黄只能在活牛体生长和培养的传统概念,它与其它培养牛黄方法相比,时间短、产量高、效益大,为牛黄的生     

牛黄产量与育黄牛血液学指标相关性的研究

育黄牛(指经植黄处理的牛)牛黄产量与其血清胆红素、血清磷脂、血清总蛋白呈极显著正相关,与其血红蛋白呈显著正相关;而与其血清钙呈极显著负相关,与其血清钠、血清谷丙转氨酶呈显著负相关。胆囊炎和向胆囊中注入致病性大肠杆菌是形成牛黄的主要原因。     

体外植黄牛胆道压力的测定

人工培植天然牛黄技术至今已有 2 0多年的历史 [1～ 3]。“牛体外牛黄发生器培植牛黄技术”[4] ,是继“牛腹腔内模拟胆囊胆汁引流和快速培植牛黄的研究”[5] ,“模拟动物胆囊研制与利用技术”[6] ,“牛双胆囊培植牛黄配套技术的研究”[7] 和“培植牛黄成因研究”[8] 最新发展的一项在国内外居领先水平的培植牛黄技术 ,该研究与国内外以前的研究相比 ,首次截断胆总管 ,改建体外胆汁流通径路 ,将牛黄发生器 (AG)由腹内移到体外 ,简化了腹腔内植入模拟胆囊的复杂操作 ,并可随时调节成黄内环境 ,有利于牛黄的形成 ,使牛黄产量在 5～ 7个月的培…     

Reproductive and leptospiral studies on beef cattle in central Queensland

The effect of rainfall on reproductive performance in beef cattle and the effects of rainfall and soil type on the prevalence of leptospirosis in beef cattle in inland central Queensland are described. Low annual rainfall produced a significant (P less than 0.05) decrease in calf branding rates. Leptospirosis (due to serovar hardjo) was serologically more prevalent after rain and on farms with high water holding capacity soils but there was no significant difference in branding rates between cattle on high or low water holding capacity soils. As a secondary mid-year rainfall peak is a feature of the area, leptospirosis due to serovar hardjo will tend to spread when most of the breeding herd is in the last trimester of pregnancy. The prevalence of leptospirosis due to serovar pomona is significantly lower in the region.     

生物饲料对不同品种肉牛肉质的影响分析

牛肉具有高蛋白质,低脂肪,含磷脂多、胆固醇少,肌肉纤维细嫩、柔软,风味独特等优点。随着人们生活水平的提高和膳食结构的改变,牛肉消费量也持续增加,为牛肉生产带来了难得的发展机遇。试验研究相同饲养管理条件下,生物饲料对不同品种肉牛肉中屠宰性能和常规营养成分的影响,证明安格斯公牛在胴体重、屠宰率、净肉重、净肉率和胴体产肉率相比西杂牛更高(P<0.05);而水分、粗脂肪、粗蛋白含量也存在较大差异(P<0.05)。这能够为提高肉牛的肉质提供科学的依据,在肉牛生产中具有重要的实践指导意义。     

秦川肉牛新品系公牛肉用性能研究

 选取发育正常、健康无病、经标准化育肥、年龄为24月龄的秦川肉牛新品系公牛5头进行屠宰及胴体分割,测定屠宰率、净肉率、胴体产肉率、肉骨比等产肉性能指标,并对里脊、西冷、眼肉、上脑、臀肉、胸肉、黄瓜条、牛腩、肋条肉、牛前10个部位取样进行水分、粗灰分、粗蛋白、粗脂肪、剪切力、失水率、系水力和熟肉率8项指标的测定。结果表明,秦川肉牛新品系公牛日增重、屠宰率、产肉率、胴体产肉率、肉骨比等生产性能较传统秦川牛均有较大幅度提高,经过标准化育肥,24月龄时已具备良好的肉用生产性能,达到国际优质肉牛品种标准;秦川肉牛新品系公牛胴体不同部位间肉品质差别较大,通过对其10个部位牛肉品质评定,西冷、上脑、里脊、眼肉为高档肉,肋条肉、臀肉、黄瓜条为中档肉,牛腩、胸肉、牛前为低档肉。     

小灰水浸提液处理青稞秸秆后在瘤胃中消失率的变化特点

西藏饲草资源有限,牛羊生产性能低,特别是冬春季节,牛羊多处于半饥饿状态。提高西藏牛羊对饲草的利用率,是西藏牛羊养殖业的重要目标之一。本试验选用西藏农牧民最常用的燃料-牛粪灰,按一定的比例水浸提牛粪灰中的碱性物质和矿物质,再按一定的比例浸泡装入青稞秸秆的无纺布滤袋内,置入羊瘤胃内测定对主要物质的消失率。结果表明:牛粪灰中K+含量较高,达到(28.4594±1.6483)mg/g,Cu2+含量为(0.5492±0.0025)mg/g,同时含有大量的其他微量元素及CO32-盐和PO43-盐。经试验,当灰水比为0.88∶10时,pH值最高,达到10.18。用这一比例灰水浸提液浸泡填入青稞秸秆的滤袋48 h后,消化后再测定总养分、纯纤维素、NDF、ADF在瘤胃中的消失率,分别显著提高了4.45%、4.89%、6.95%和5.80%。由此可见,利用廉价的牛粪灰水浸提液浸泡秸秆能显著地提高纤维素在牛羊瘤胃中的利用率。     

Economic evaluation of the production impact of bovine schistosomiasis and vaccination in the Sudan

This study was done to evaluate the estimated economic consequences of the recent discovery that an irradiated Schistosoma bovis vaccine was effective in reducing mortality and intensity of infection in cattle after field exposure to S. bovis in the White Nile province. The benefits and costs were hypothesized to occur over a 5-year period starting after the vaccine had been further developed to optimal commercial usefulness.

The potential benefits of vaccination are from the avoidance of mortality and growth delay losses caused by S. bovis infection and were based on an owner survey conducted in 1981. These benefits were discounted from the time of their potential marketing opportunity to the first year of a vaccination program at 15% per annum and were valued on a basis of 1982 prices for live cattle exported to Egypt and Saudi Arabia. Variations in benefits stem from degree of infection probability, mortality and morbidity estimates and percent of animals vaccinated. Since clinical schistosomiasis (“gorag” — sunken-eyed appearance) and associated production losses occur almost exclusively in 6- to 30-month-old cattle, and there is evidence for long-term immunity, vaccinations would be given to cattle in this age-specific group or younger once in their lifetime. The principal variation in vaccination program costs, also valued at 1982 prices, is from vaccine production costs; $0.50 or $4.00 per dose. A vaccine efficacy of 70%, observed in a previously reported field trial, was used in these calculations.

Present value benefit—cost (b–c) ratios were estimated for the central, western and southern areas for high- and low-level effects of S. bovis impact on production and the vaccination program, cost and effectiveness. In an area (central provinces) of high infection probability (90%), high percentage of animals vaccinated (90%), high mortality (7.1%), and low vaccine production costs, the b–c ratio was 12.7. In contrast, a b–c ratio of 0.7 was estimated for an area (southern provinces) assuming low infection probability (50%), low percent of animals vaccinated (50%), lower mortality (3.55%) and high vaccine production costs. Potential returns from increased future milk and calf production and from faster herd build-up with younger females were not included in these benefit calculations. These results indicate that under most conditions further development of the vaccine and cost-effective vaccine production techniques would yield very favorable returns from improved livestock production efficiency in the Sudan. Export prices were assumed to not vary significantly with increased supply of export-quality cattle resulting from the estimated production losses avoided by vaccination against schistosomiasis.     

西北地区养牛业进展

我国西北地区包括陕、甘、青、宁、新五省区,总土地面积296.6万km2,占全国的30.9%,人口占7.23%.2003年末存栏黄牛1 333.9万头,奶牛253.0万头,分别占全国相应牛数的13.4%和28.3%;总产牛肉60.8万t,牛奶270.1万t,分别占全国产量的9.6%和15.5%;奶牛平均每头年产奶1 068 kg,为同期全国平均每头产奶量(1 955 kg)的54.6%,出栏牛产肉量平均每头120.3 kg,为全国平均每头出栏牛产肉量(134.0 kg)的89.9%.新疆是西北地区的牛肉、牛奶生产大区,产量分别占西北区总产量的47.3%和41.8%.甘肃、青海、新疆是我国传统牧区,可发展与其草原改良相适应的低成本养牛业.西北区养牛科技进步对养牛业发展起到推动作用,遗传改良、胚胎移植、黄牛选育、高产奶牛培育、饲草基地建设等都取得了显著进展.     

皮南牛产业发展现状及存在问题的对策与建议

皮南牛是河南省南阳市新野县的一个培育的专门化肉用品种,该品种是利用皮埃蒙特牛和南阳牛进行杂交改良育成。皮南牛是一种皮薄、毛细,皮质紧密而富有弹性的牛,由于皮质好,可以作为一种生产高档皮革的优质原料。在肉质方面,其肉质细嫩,富含维生素A和多种蛋白质,脂肪和胆固醇含量很低,受到消费者的广泛好评。本论文综述了皮南牛的培育历程、发展现状、存在问题、发展对策和发展前景,提出了对于皮南牛的开发利用措施,并对未来皮南牛产业的发展做出了展望。     

南方肉牛产业发展的优势和途径

本文论述了南方水热条件充足、草山草坡资源丰富、市场对外依存度高、投资资金充足、饲草成本低等肉牛产业发展的有利条件,结合南方肉牛养殖的成功案例,从品种改良、饲草体系建设、放牧与舍饲二元养殖方式、南方高档牛肉生产开发等几个方面,分析了南方肉牛产业发展的途径,提出将南方建设成为继北方牧区畜牧业、农区畜牧业之后的第三个草食畜牧业基地,形成"南方农区牧场"。     

Ruminant heat stress: effect on production and means of alleviation

A review of the literature indicates heat stress generally causes lower milk production, decreased growth rate for cattle and lambs, but little effect on wool production. Breed and diet affects the degree of adverse response. Heat stress is caused primarily by high air temperature, but can be intensified by high humidity, thermal radiation and low air movement. Improving performance of animals under warm conditions involves breeding and management and modifying the environment. The former includes selection for heat tolerance, use of crossbred animals, diets with low heat increment in relation to energy for production and control of diseases and parasites. Environmental modifications may include provision of shades, use of water for evaporative cooling and increased air movement.