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安徽荷斯坦牛的体型线性评定分析 总被引:10,自引:0,他引:10
本文根据 1996年中国奶牛协会颁布的《中国荷斯坦牛体型线性鉴定实施方案 (试行 )》 ,采用线性评定 1~ 5 0分制 ,对安徽荷斯坦牛进行体型线性评定。结果表明 ,在一级线性性状中 ,体高、胸宽、尻宽、后房高度、乳头长度的评分随胎次增加而增加 ,而前房附着、乳房深度、后房高度的评分随胎次增加而减少。安徽荷斯坦牛平均体高段 137~139cm ,尻宽性状有显著的地区差异 (P <0 .0 5 ) ,在后房高度、乳头长度性状上不同地区表现一致且上乘 ,在乳房深度、前房附着性状上的表现存在着明显的地区差异 (P <0 .0 5 ) ,且均未达到奶牛体型的理想结构 相似文献
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淮南地区荷斯坦奶牛乳用特征的线性评定 总被引:1,自引:0,他引:1
随机选择安徽淮南乳品公司的荷斯坦奶牛493头(1~11胎)进行奶牛乳用特征性状即楞角性、尻宽、尻角度、后肢侧视、蹄角度的线性评定。结果表明:淮南地区荷斯坦奶牛乳用特征性状的表现中等偏好,楞角性、尻宽、尻角度、后肢侧视、蹄角度的评定等级分别是佳、优、中、中、良;优秀率是20%,中等率为40%。同时,楞角性、尻宽、蹄角度的线性评分随胎次变化而变化的幅度很小,且未表现出一定的规律;而后肢侧视、尻角度的线性评分在1~5胎内随胎次的升高而有明显的升高,并且前者的变异幅度大于后者。 相似文献
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《畜牧与兽医》2021,(10)
为了选出优秀体型奶牛群体,提高全群产奶量,试验选取不同血统含量、不同世代、不同胎次的286头奶牛开展体型线性评分研究。结果显示:纯种荷斯坦牛体型总评分、乳房评分、体躯结构评分(P0.05)以及乳用特征评分高于或显著高于低代杂种,而低代杂种肢蹄评分、尻部评分高于纯种;2世代奶牛在肢蹄评分、体躯结构评分、乳用特征评分方面显著高于0世代(P0.05),0世代尻部评分显著高于2世代(P0.05);2胎次奶牛总评分、乳房评分、肢蹄评分以及体躯结构评分显著高于1胎次(P0.05),2胎次以后总评分呈下降趋势。提示:应加强纯种荷斯坦牛的肢蹄和尻部结构选育工作,从而减少肢蹄病和产科疾病的发生,使得奶牛群体高产健康长寿。 相似文献
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《中国畜牧杂志》2020,(5)
本研究旨在对新疆褐牛乳肉兼用牛体型外貌线性评定方法进行探究。通过测定新疆伊犁河谷483头新疆褐牛一胎或二胎生产母牛的体重、体尺、乳房结构性状共18个指标,对这18个指标进行极值、方差、相关性、聚类和主成分计算分析。结果表明:新疆褐牛母牛18个性状指标中有11个性状变异系数在10%以上,说明新疆褐牛选育提高潜力较大;在12个体尺性状中,体高、体斜长、胸围、胸底宽、腹围、尻宽、尻长和坐骨端宽各性状间表现为极显著相关性;17个体尺、泌乳性状可通过聚类分析分成8类,通过主成分值贡献值选取前5个主成分,第一主成分反映综合信息量最大。综合上述结果并借鉴奶牛、中国西门塔尔牛、国外褐牛体型外貌线性评定方法,本研究提出了伊犁河谷新疆褐牛9分制线性外貌评定方法,4个特征性状为整体结构、尻部、腿蹄、乳房,为今后新疆褐牛鉴定、选种选配和选育提高方向提供指导。 相似文献
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淮南地区荷斯坦奶牛15个一级体型性状的线性评定 总被引:1,自引:1,他引:0
选择安徽淮南乳品公司为试验点,随机抽取荷斯坦奶牛493头(1~11胎)进行奶牛15个一级体型性状即体高、胸宽、体深、楞角性、尻角度、尻宽、后肢侧视、蹄角度、前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置、乳头长度的线性评定。结果表明:淮南地区荷斯坦奶牛15个一级性状评分分别是13.38分、35.69分、31.46分、31.16分、40.36分、40.49分、32.61分、41.14分、31.95分、46.98分、29.09分、37.47分、15.08分、39.74分和20.82分;功能分各为68分、92分、81分、81分、70分、90分、72分、89分、82分、92分、79分、88分、65分、88分、74分;评定等级分别是中、优、佳、佳、中、优、中、良、佳、优、好、良、中、良、中。同时,在1胎~≥6胎各胎次奶牛平均的整体评定等级各为佳(80.90分)、佳(81.47分)、佳(80.28分)、佳(79.50分)、好(78.57分)、佳(79.60分),而淮南地区荷斯坦奶牛总的平均整体评定等级为佳(80.27分),表现较为理想。 相似文献
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奶牛体型外貌鉴定对后备牛的选择及育种工作有极为重要的作用。它是提高奶牛场生产效率和经济效益的一项首要工作。9分制鉴定奶牛分为五大志,即结构/容量,尻部、肢蹄、泌乳系统和乳用特征,共24个性状,对每一性状给予1-9分的评分,最终根据此评分,选育高产、健康、优秀、长寿的优质牛群以获得最好的经济效益。 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