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目的:估计新疆乌鲁木齐种牛场荷斯坦牛产奶性状的遗传参数及育种值,为该场荷斯坦种公牛的选种选配计划提供理论依据。方法:以新疆乌鲁木齐种牛场2009~2015年间荷斯坦泌乳母牛的产奶性能记录资料为基础,运用DMUAI-REML算法及动物模型BLUP法,对荷斯坦牛产奶量及乳成分进行单性状方差组分及育种值估计。结果:牛场荷斯坦种公牛后代母牛的产奶量、乳脂率、乳蛋白率、乳糖率及非脂固形物的遗传力分别为0.14、0.13、0.14、0.09、0.11。6头种公牛里估计得到产奶量育种值最高的是65206012号种公牛,乳脂率、乳蛋白率、乳糖率、非脂固形物育种值最高的是11101917号种公牛。结论:使种公牛生产性能评定的更准确,需综合考虑产奶量和乳成分等性状,最终对种公牛进行选育选配。 相似文献
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奶牛泌乳曲线数学模型的遗传分析 总被引：7，自引：3，他引：7
本文采用Wood、改进多项式、回归模型各参数估值及拟合、预报奶量进行了方差分析,遗传力、遗传相关估计及BLUP法育种值估计。方差分析结果表明,产犊季节和胎次对各性状具有较为显著的影响。各遗传相关的估值均较高,这是由环境因素及取样情况所致。实际及估计305天产奶量的遗传力估值较高,Wood模型参数c、改进多项式模型参数d及回归模型参数d、e的遗传力估值也相对较高。各估计、预报奶量及各选定模型参数的BLUP育种值排队序号与实际305天产奶量BLUP育种值排队序号均呈极显著的秩相关(p<0.001).这表明可以用估计和预报奶量及模型参数来评定种公牛的优劣。这对奶牛生产和育种实践具有一定的实践意义。 相似文献
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目的:估计新疆乌鲁木齐种牛场新疆褐牛产奶性状的遗传参数及育种值,探究母体效应对该场新疆褐牛后代产奶性状的影响,提高该场母牛选育的准确性,进一步为该场奶牛的选种选配计划提供理论依据。方法:以新疆乌鲁木齐种牛场2009~2015年间新疆褐牛泌乳母牛的产奶性能记录资料为基础,利用两种模型,一种考虑母体效应,一种未考虑母体效应,运用DMU软件AI-REML算法及动物模型BLUP法,对新疆褐牛产奶量及乳成分进行单性状方差组分及育种值估计和排队。结果:母体效应对个体母牛的产奶量、乳脂率、乳蛋白率、乳糖率和总固体的遗传参数及育种值均有不同程度的影响,且各性状育种值的母牛排名具有不一致性。结论:当考虑母体效应后,该场新疆褐牛母牛产奶量的遗传力及育种值降低,并在一定程度上增加母牛乳成分的遗传力和育种值。 相似文献
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不同选择指数对中国荷斯坦种公牛综合育种值排名的影响 总被引：2，自引：0，他引：2
本研究旨在探讨包含不同性状的综合选择指数对荷斯坦种公牛排队的影响。收集了全国199个牛场的664 284头荷斯坦牛产奶量、乳脂率、乳蛋白率、乳脂量、乳蛋白量、体细胞数以及35 281头荷斯坦牛的体型性状。然后采用多性状动物模型BLUP法预测生产性状和体型性状的育种值,计算3种不同综合选择指数下47头种公牛的综合育种值,并对其排队进行了比较。结果显示,使用包含产奶量、乳脂率、乳蛋白率、体细胞评分4个性状的综合选择指数（TMI1）和包含乳脂量、乳蛋白量、体细胞评分3个性状的综合选择指数（TMI2）对公牛的排队一致性很高,秩相关为0.94;只包含生产性状的综合选择指数（TMI1、TMI2）和加入了体型性状的综合选择指数（TMI3）对公牛的排队差异很大,秩相关分别为0.76和0.67。这些结果提示,乳脂量、乳蛋白量可以替代产奶量、乳脂率、乳蛋白率纳入综合选择指数,体型性状进入综合选择指数对评价种公牛综合遗传素质具有重要作用。 相似文献
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选择新疆乌鲁木齐种牛场6头新疆褐牛种公牛及后代母牛为研究对象,运用DMU软件AIREML算法及动物模型BLUP法,估计该场后代母牛的遗传参数及种公牛的育种值,并进行排序,为该场褐牛种公牛及后代母牛的选种选配计划提供理论依据。结果表明:该场新疆褐牛后代母牛的产奶量、乳脂率、乳蛋白率、乳糖率及总固体的遗传力分别为0.35、0.06、0.19、0.06、0.04;00233号种公牛在所选公牛中的各项育种值最高,196318号种公牛各项育种值最低。通过研究结果,可对公牛各项育种值高的后代母牛进行选育选配,进一步扩大核心群体,为该场牛品种的改良提供决策。 相似文献
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《畜牧兽医学报》2021,(1)
旨在探究河北省中国荷斯坦牛产奶和体型性状的遗传参数,为育种提供参考。本研究收集了2012—2018年河北省133个牛场8 891头中国荷斯坦母牛第一胎次的3个产奶性状记录(产奶量、乳脂率和乳蛋白率)和26个体型性状记录,利用DMU软件,以场年季、产犊月龄、鉴定年季和鉴定员效应为固定效应,以个体的加性遗传效应为随机效应,采用AIREML结合EM算法并配合动物模型对产奶性状、体型性状进行了遗传参数估计。结果表明,产奶性状的遗传力估计值范围为0.15(产奶量)～0.32(乳脂率),体型性状遗传力估计值范围为0.01(体型总分)～0.28(后乳房附着宽度)。产奶性状与体型性状间的遗传相关估计值范围分别是-0.43(产奶量与骨质地)～0.31(产奶量与尻部)、-0.59(乳脂率与尻部)～0.20(乳脂率与前乳头位置)以及-0.34(乳蛋白率与前乳头长度)～0.23(乳蛋白率与后乳头位置)。大部分体型性状与产奶量之间为遗传正相关,而与乳脂率和乳蛋白率为遗传负相关。加强对产奶性状及体型性状中的中高遗传力性状的选择,尤其对后乳房性状以及体型总分的选择,有利于奶牛生产性能的提高。 相似文献
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应用多性状方差分量估计模型和典范转化的REML算法,估测了西安市草滩农场、西安市一奶场、二奶场和三奶场的7个牛群1980～1989年间2985头初产母牛的泌乳天数、泌乳期产奶量、305天产奶量、标准乳产量、乳脂量,乳蛋白量,乳脂率,乳蛋白率,乳糖含量以及非脂固形物等10个重要经济性状的遗传力、遗传相关、表型相关及环境相关系数,结果是、10个性状的遗传力分别为0.21、0.27、0.29、0.31、0.41、0.26、0.58、0.50、0.40和0.31;通过净遗传相关分析,揭示了305天产奶量、乳脂量、乳蛋白量、乳脂率和乳蛋白率之间的真实遗传相关关系,表明选择乳脂量可同时提高产奶量、乳蛋白量及乳脂率,因而是一举多得的选择方法,这要比单纯的产奶量选择法或约束乳脂率选择法效果更好。 相似文献
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以新疆呼图壁种牛场中国荷斯坦牛为研究对象,利用动物模型BLUP法对中国荷斯坦牛各生产性能性状进行育种值估计并制定总性能指数。结果表明:在群母牛305d产奶量、乳脂率、乳蛋白率育种值排名第一的分别是732210233号、724409179号和119870098号,体细胞评分育种值最低的是766963365号母牛;种公牛305d产奶量、乳脂率、乳蛋白率育种值分别是133412077号、60755967号和13号,体细胞评分育种值最低的是12000167号。根据305天产奶量、乳脂率、乳蛋白率和体细胞评分育种值,制定了总性能指数公式,选留390头母牛为核心群母牛。 相似文献
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《中国畜牧杂志》2021,(6)
我国自开展奶牛生产性能测定(DHI)以来,积累了大量DHI数据,这为奶牛群体遗传参数估计和遗传评定奠定了良好的基础。本研究收集了北京地区1998—2018年间131个牛场的99 823头中国荷斯坦奶牛的头胎测定日数据,共计817 208条,以及全部牛只的系谱记录信息,采用了单性状随机回归模型配合4阶Legendre多项式分析中国荷斯坦牛产奶性状的遗传参数以及育种值估计,计算过程采用DMU软件的AI模块。结果表明:北京地区荷斯坦牛产奶量、乳脂率、乳蛋白率、乳脂量、乳蛋白量5个性状的305 d泌乳期遗传力分别为0.28、0.53、0.63、0.25、0.24,1990—2016年间各产奶性状的平均年遗传进展分别为10.52 kg、-0.00046%、-0.00011%、0.30kg、0.32kg。该研究结果为进一步提高选种准确性和遗传进展提供了依据,为北京地区制定合理的育种目标和进行遗传评估提供了理论参考。 相似文献
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本研究通过采用陕西省宝鸡市陇县陇州奶牛繁育中心及7个陇州奶牛开放核心群20年来育种资料的数据,对陇州奶牛的主要性状(305d产奶量、乳脂率、乳蛋白率、18月龄体重、18月龄日增重以及体型评分)进行分析,并运用动物模型及MT-DFEML(多性状非求导REML)软件,计算了这些性状的遗传参数。结果主要性状遗传力分别为0.32、0.28、0.27、0.32、0.25和0.19。产奶量与乳脂率、乳蛋白率均呈负相关,与体重、日增重呈正相关,乳脂率与乳蛋白率呈正相关,乳成分与体重没有遗传相关。体重、日增重与体型评分呈正相关。 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