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在半舍饲半放牧的饲养条件下,用波尔山羊(B)、萨能山羊(S)、南江黄羊(N)、皖北白山羊(W)等山羊品种进行了杂交组合试验。1材料与方法1.1试验动物杂交父本是从安徽省畜牧局、四川、山西等地引进的波尔山羊、南江黄羊、萨能山羊,杂交母本为经产的本地皖北白北羊。1.2试验地点试验在蒙城县柳林镇畜牧兽医站养羊场进行,时间为2000年9月13日～2002年5月27日。1.3试验设计与测定指标共设置4个杂交组合,分别为B×S×W,B×N×W,N×S×W,N×B×W,从 各组所产的三元杂交羊中随机挑选出生日期相近的羔羊进行生产性能测定,同时记录各组合中三元杂… 相似文献
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不同山羊品种杂交后代生长育肥效果观察 总被引：4，自引：0，他引：4
在以农户放牧为主的饲养条件下,用波尔羊、奴比羊、南江黄羊和川东白山羊(简称本地羊,下同)等山羊品种进行了多个杂交组合试验.结果表明波×本F1、波×南F18月龄体重分别为33.05 kg、34.67 kg,分别极显著高于其它组合(P＜0.01),南×本F1与奴×本F18月龄体重差异不显著(P＞0.05),波×南F1出生～8月龄(240天)全程平均日增重达134.17 g,波×本F1同期日增重为127.42 g;波×本F1阉羊、波×南F1阉羊7月龄屠宰率分别为47.25%、49.80%.分别比奴×南F1、奴×本F1同龄羊提高0.77、1.68个百分点和3.32、4.23个百分点.表明以波尔羊为父本与南江黄羊和本地羊杂交,其后代具有较优的生长育肥效果,此两个组合是肉羊生产中的优秀杂交组合. 相似文献
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肉用山羊品种杂交组合试验 总被引：1，自引：0，他引：1
在以农户放牧为主的饲养条件下 ,用波尔羊 (Bo)、奴比羊 (Nu)、南江黄羊 (Na)和川东白山羊 (简称本地羊Bd ,下同 )等山羊品种进行了Bo×Bd、Nu×Bd、Na×Bd、Bo×Na、Nu×Na等杂交组合试验。结果表明 :Bo×BdF1 、Bo×NaF1 8月龄体重分别为 33.0 5、34.6 7kg ,分别极显著高于其它组合 (P <0 .0 1) ,Na×BdF1 与Nu×BdF1 8月龄体重差异不显著 (P >0 .0 5 ) ,Bo×BdF1 、Bo×NaF1 阉羊 7月龄屠宰率分别为 4 7.2 5 %、4 9.80 % ,分别比Nu×NaF1 、Nu×BdF1 同龄羊提高 0 .77、1.6 8个百分点和 3.32、4 .2 3个百分点。试验表明Bo×Na、Bo×Bd羊是肉羊生产中的优质杂交组合 相似文献
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山羊不同杂交组合的生产性能测定 总被引：1，自引：0，他引：1
浦江县地处浙江中部 ,属丘陵山区县。境内牧草资源丰富 ,养羊历史悠久。为了改良本地山羊 ,提高养羊的经济效益 ,采用不同杂交组合进行对比试验 ,先后选用萨能山羊、马头山羊、波尔山羊作父本 ,用本地山羊、萨本山羊作母本的杂交组合试验。结果表明杂种优势 :波萨本 >马萨本 >波本 >萨本 相似文献
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三峡库区山羊经济杂交组合筛选试验 总被引：4，自引：0，他引：4
在三峡地区粗放的饲养条件下,以波尔山羊,南江黄羊,莎能山羊为父本,当地的宜昌白山羊为母本,分三个杂交组合开展筛选试验,结果表明,波本杂交组合的产羔率为１５６％,接近地方山羊,波本杂交羊的初生重,４月龄重,８月龄重分别为３．０ｋｇｒ,２０．５ｋｇ,２５．１ｋｇ分别比地方山羊提高１００．０％,１４７．０％,１３２．４％,体型趋向父本,肌肉丰满,适应性强,是最优的杂交组合。南本杂交羊的初生重,４月龄重, 相似文献
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波尔山羊与徐淮山羊的杂交试验 总被引：4，自引：1，他引：3
为进一步探明波尔山羊与本地徐淮山羊的杂交效果,加快波尔羊的杂交利用,给波尔羊的推广和建立本地肉羊生产带,提高本地羊产肉性能提供科学依据,于1998年至1999年选点进行定点观察,开展了波尔山羊的杂交试验。1 材料和方法11 试验羊的选择和分组 杂交父本系从徐州家畜改良站引进的波尔山羊冻精;选择体型外貌、生产性能基本一致的本地徐淮母山羊作为母本,年龄2～3岁,健康无病,分成试验组(波×本)和对照组(本×本),平均每组22只能繁母羊。12 观测内容 观测各组后代的繁殖成绩和初生、2、6、12月龄体重和体高、体长、胸围等主要体尺;测定其… 相似文献
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以本地母羊为第一母本、萨能山羊为第一父本、波尔山羊为终端父本 ,进行三元杂交试验 ,来观察波×萨本三元杂交一代、二代和波×本二元杂交一代、二代的生长性能 ,另外采取不同的饲养管理 ,观察各组的杂交后代从出生到十月龄时成活率的差异。1 材料与方法1.1 试验母羊 :随机抽测分布于如东县兵房、大豫、长沙、掘港、袁庄、河口等镇的于 2 0 0 1年底前产羔、健康无病的母羊。母羊品种有本地、波×本和波×萨本 ,其杂交后代分别为波×本二元杂交一代、二代和波×萨本三元杂交一代、二代。1.2 试验分组 :共分成A、B、C、D四组 ,波×本… 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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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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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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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 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