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安格斯牛杂交改良务川黑牛效果初报 总被引：1，自引：0，他引：1
[目的]为了探索安格斯牛改良务川黑牛的杂交效果.[方法]采用直肠输精法,用安格斯牛的细管冻精杂交改良务川黑牛.[结果]表明:安务杂一代F1初生重比务川黑牛高,公母分别比务川黑牛增加4.3 kg、4.7 kg,差异极显著(P＜0.01).在农村饲养管理条件下,安务杂一代F1牛6月龄、12月龄、18月龄的体重都高于同龄务川黑牛.从初生到6月龄、6～12月龄、12～18月龄各年龄段F1公母牛日增重都高于同年龄的务川黑牛的日增重,经T检验,差异均极显著(P＜0.01).从体尺变化看安务杂一代F1牛各阶段主要体尺相对增长较快,如体高,初生后随月龄的增大而增高.到12月龄后,其体高与同龄务川黑牛相差不大,但与产肉性能有关的体长、胸围、髂宽等项体尺均比务川黑牛增长幅度大.对18月龄安务杂一代F1牛和务川黑牛公牛进行90 d的肥育实验,随机抽5头行进屠宰测定,其屠宰率,净肉率分别为55.75％、45.19％,比务川黑牛的56.11％、46.51％分别提高了2.68和2.21个百分点.[结论]用安格斯牛杂交改良务川黑牛,其后代的体尺、体重和产肉性能、适应能力、役用等方面都得到了改善和提高,并使杂交牛体型逐步向肉役兼用型转化,改良效果明显. 相似文献
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《中国草食动物科学》2016,(4)
该研究对农户饲养的务川黑牛及其与西门塔尔牛、利木赞牛、安格斯牛的杂交F1牛的初生、6月龄、12月龄、18月龄及24月龄的体尺、体重进行了测定。结果表明:1务川黑牛经杂交改良后,其后代西×务F1、安×务F1、利×务F1牛各年龄段主要体尺都有极显著提高(P0.01),杂交F1牛的初生重和各月龄体重也均有极显著提高(P0.01);2杂交F1牛初生至24月龄平均日增重,西×务F1、安×务F1、利×务F1公(母)牛分别为369.0 g(359 g)、405 g(377 g)、382 g(362 g),比务川黑牛公(母)牛的216 g(202 g)分别提高了70.83%(77.25%)、87.50%(86.63%)、76.85%(79.21%);杂交F1公(母)牛的初生至24月龄平均生长系数分别比务川黑牛公(母)提高了12.10%和7.15%;33种杂交组合F1公(母)牛体尺间差异均不明显(P0.05),增长速度以安×务F1牛提高幅度最大(P0.01)。表明用西门塔尔牛、利木赞牛、安格斯牛杂交改良务川黑牛可以取得良好的改良效果,其中以用安格斯牛杂交改良效果最好。 相似文献
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实验旨在了解安格斯牛、利木赞牛和西门塔尔牛与务川黑牛杂交一代的产肉性能和肉品质。随机选取24月龄安务F1、利务F1、西务F1和务川黑牛公牛各3头,测定其屠宰性能和肉品质指标。结果表明:3种牛对务川黑牛杂交改良效果显著(P<0.05),屠宰率、肉骨比以利务F1牛最高,胴体重、净肉重、净肉率以安务F1牛最高,眼肌面积以西务F1牛最高;利务F1牛的熟肉率最高,安务F1牛的剪切力最低,肉色L45min、a45min、b45min值以西务F1牛色泽最亮,安务F1牛肉粗脂肪含量显著低于务川黑牛,利务F1牛肉与务川黑牛肉大理石纹都为3级,安务F1和西务F1牛肉大理石纹则为2级;系水力、滴水损失、水分、蛋白质、pH在不同杂交组合之间差异不显著。综合产肉性能和肉品质考虑,建议选择利木赞牛和安格斯牛作为务川黑牛杂交改良的父本进行推广。 相似文献
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[目的]研究安格斯牛对大别山牛的杂交效果。[方法]对安格斯牛×大别山牛杂交F1代(安—大F1)和大别山牛各24头进行了初生、6月龄、12月龄和24月龄体重和体尺性状测定,对照组和试验组各随机选择3头持续育肥至24月龄后进行了屠宰测定。[结果]安—大杂交F1代牛具有较高的杂种优势,安—大杂交F1代牛初生、6月龄、12月龄、18月龄和24月龄体重和体尺指标均明显优于大别山牛;24月龄时安—大杂交F1代的宰前体重极显著高于大别山牛(P<0.01),胴体重和净肉重均显著高于大别山牛(P<0.05)。[结论]用安格斯牛与大别山牛杂交,杂交效果明显,具有较高的推广及应用价值。 相似文献
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不同杂交组合改良北塔山土种牛生长性能与肉用性能的比较 总被引：1，自引：0，他引：1
通过对安格斯牛、利木赞牛、西门塔尔牛和新疆褐牛与北塔山牧场土种牛杂交一代的生长性能指标和肉用指标的测量,比较了4种牛杂交改良北塔山牧场土种牛的效果。结果显示:4种牛对北塔山土种牛的杂交改良效果均极显著,其中以利木赞牛为父本和以西门塔尔牛为父本的杂种牛在3月龄体重、6月龄体重、12月龄体重、18月龄体重、日增重、体尺、胴体重、净肉重、屠宰率、净肉率、胴体产肉率等指标上均表现出了优于土种牛和其他2个杂交组合。建议北塔山牧场选择利木赞牛或西门塔尔牛作为本地土种牛杂交改良的父本进行推广。 相似文献
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[目的]为了提高云南黄牛的生产性能,优选主要的杂交改良父本,开展云南黄牛杂交改良。[方法]用西门塔尔牛、短角牛、安格斯牛、海福特牛等分别与云南黄牛母本杂交,测定不同杂交组合后代初生、6月龄、12月龄、24月龄的体重体尺。[结果]云南黄牛经过杂交改良后,改良效果良好,杂交后代对云南高原的气候条件适应性良好。在农村饲养条件下,西×云杂一代牛初生重平均为24.57kg,6月龄体重平均为135.83kg,12月龄体重平均为196.21kg,24月龄体重平均为344.24kg,分别比本地黄牛提高74.13%,59.20%,56.53%和78.10%。短×云杂交一代牛初生重平均为22.28kg,6月龄体重平均为117.20kg,12月龄体重平均为193.56kg,24月龄体重平均为314.86kg,分别比本地黄牛提高57.90%,38.10%,54.21%和62.90%;安×云杂交一代牛犊牛初生重平均为21.21kg,6月龄体重平均为134.34kg,12月龄体重平均为196.18kg,24月龄体重平均为268.45kg,分别比本地黄牛提高50.32%,57.45%,56.51%和38.89%;海×云杂交一代牛初生重平均为22.78kg,6月龄体重平均为124.97kg,12月龄体重平均为190.52kg,24月龄体重平均为289.50kg,分别比本地黄牛提高61.45%,46.47%,51.99%和49.78%。[结论]西×云杂一代牛、短×云杂交一代牛、安×云杂交一代牛和海×云杂交一代牛生产性能显著提高,效益明显。 相似文献
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《中国牛业科学》2016,(5)
[目的]研究安格斯牛、西门塔尔牛对北沙牛的杂交效果。[方法]对北沙牛、北沙牛与安格斯杂交一代(北安F1)、北沙牛与西门塔尔牛杂交一代(北西F1)共45头母牛进行了体重及体尺指标测定。[结果]北安F1牛、北西F1牛初生重比北沙牛高,其中北西F1牛与北沙牛差异显著(P0.05)。在本地传统饲养管理条件下,北安F1牛、北西F1牛的6月龄、12月龄、18月龄、24月龄体重都高于同龄北沙牛。从初生到6月龄、6~12月龄、12~18月龄、18~24月龄各年龄段杂交母牛日增重都高于同年龄的北沙牛。从体尺变化看,北安F1牛和北西F1牛各阶段主要体尺相对增长较快,出生后随月龄的增大而增高。到12月龄后,北安F1牛体高与同龄北沙牛相差不大,北西F1牛体高高于北沙牛,但北安F1和北西F1与产肉性能有关的体长、胸围等项体尺均比北沙牛增长幅度大。[结论]用安格斯牛、西门塔尔牛与北沙牛杂交,其后代在体尺、体重、日增重等方面都得到了改善和提高,杂交效果明显。 相似文献
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为了确定适宜的湘南黄牛杂交组合,分别以安格斯、西门塔尔、短角、利木赞等4个肉用牛品种为父本,湘南黄牛为母本开展杂交试验,并对改良牛的体重和体尺进行测定,且进行了数据分析。结果表明:安本杂、西门塔尔、短角、利木赞牛对改良湘南黄牛的杂交优势十分明显,其中西门塔尔牛的改良效果最好。F1代公母牛初生、6月龄、12月龄、18月龄、24月龄体重较同龄湘南黄牛公母牛分别提高了72.62%和72.43%、50.25%和47.80%5、4.34%和59.46%、83.24%和74.68%、72.65%和76.23%,差异显著(P<0.05)。西门塔尔F1代公母牛24月龄体高、胸围、体斜长较同龄湘南黄牛公母牛提高了11.46%和12.02%、22.60%和23.51%、14.87%和15.54%,差异显著(P<0.05)。 相似文献
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贵州黎平黄牛杂交改良初步研究 总被引：2，自引：1，他引：1
对农户饲养的黎平黄牛及其与西门塔尔牛、安格斯牛、利木赞牛的杂交F_1代的初生、6月龄、12月龄、18月龄、24月龄的体重、体尺进行了测定,结果表明;(1)黎平黄牛经杂交改良后,各年龄阶段各主要体尺都有极显著提高(P＜0．01),初生重和各月龄体重均有显著提高(P＜0．05);(2)初生至24月龄平均日增重,西×黎F_1、安×黎F_1、利×黎F_1公(母)牛分别为395g(366g)、364g(332g)、391g(360g),比黎平黄牛公(母)牛的192g(175g)分别提高了105。7%(109．1%)、89．6%(89．7%)、103．6%和105．7%)。 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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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
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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