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我国优质鸡育种技术现状与创新方向探讨 总被引：1，自引：0，他引：1
我国人民素有“黄鸡”消费习惯。从20世纪90年代始,因经济水平的提高带动了消费的巨大增长,我国优质鸡生产进入了旺盛发展时期。1990年我国的肉鸡产量为258万吨,2000年增长为1159.2万吨;1990年共出栏优质肉鸡6亿只,2000年出栏达18亿只,每年优质鸡生产量以20%的速度递增。据FAO统计,2005年我国禽肉产量居世界第二,达1468.9万吨,占世界总产量8101.4万吨的18.13%;我国禽肉中鸡肉产量占69.09%,而优质肉鸡的生产数量已占白羽肉鸡生产数量60%左右。以江苏为例,1996年全省生产优质鸡0.5亿只,2005年全省优质鸡的生产已达4亿只左右。我国优质鸡产业迅猛发展的原因一方面是由于广阔的市场空间,另一方面则更得益于在育种方法、饲养技术等方面的长足进步,特别是近年来,优质鸡产业化生产格局已在一些地区初步形成。下面就我国优质鸡育种发展历史、水平、存在问题进行分析,并对未来的优质鸡育种技术创新方向进行探讨。 相似文献
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<正> 我国加入WTO后,从国外返回的禽肉产品告诉我们,出口禽肉产品打入同际市场的技术壁垒越来越高,要遵循OIE的食品卫生安全要求规则,就要改变我们传统的畜牧生产方式,不能使用禁用药物和抗生素超标。目前,药物残留的危害直接影响着食品卫生安全,若不加防范就 相似文献
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江苏省苏州市乃至全国猪肉产品的质量现状令人担忧 ,主要表现在 :①猪疫病导致其产品有害菌虫污染 ;②猪肉产品中的药物残留超标 ;③猪肉产品中有毒有害物质残留超标。食用猪肉而中毒的事件屡有发生 ,成为危害人体健康的隐形杀手。猪肉产品的卫生安全问题已成为我市“建设最适宜人居和创业的城市”的重要障碍。苏州市地产猪供小于求 ,外地猪源的质量安全令人担心。社会对优质安全猪肉产品的消费需求日益迫切。1 地方品种猪资源现状太湖猪以繁殖性能高和肉质鲜美等优良遗传特性而引起世界养猪界的高度关注。美、法、日等国先后从我国引进了… 相似文献
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Dr Ken Laughlin 《中国禽业导刊》2006,23(19):74-75
中国是肉鸡产品消费的主要国家，也是禽肉产品主要进出口国家。而安伟捷是肉鸡产品的主要育种公司。安伟捷和中国对未来拥有着共同的利益。 相似文献
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影响畜禽产品卫生质量有两个方面的原因：是动物疫病，二是有害物质如药物、黄曲霉菌毒素、重金属元素等残留。随着人们健康意识的增强，追求肉、蛋等食品安全、优质、无残留、无疫病的消费观念已被人们普遍接受。绿色畜禽产品的生产适应了当今人们的消费需求，可以预见，绿色产品必将成为人们的消费主流，而发展绿色养殖也必 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献