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本研究对西镇种公牛初夏精液品质八项指标进行了相关分析和重复力估测。结果表明:活力与密度(r=0.977)、密度与存活指敬(r=0.9946)、活力与冻后活力(r=0.894)、活力与存活指数(r=0.9522)、顶体完整率与顶体损害数(r=0.9493)相关显著。精子密度(0.6726)、精液存活指数(0.7761)、和精液损害数(0.8697)为高重复力,每次射精量(0.4246)、活力(0.4775)和冻后活力(0.5064)为中等重复力;精子畸形率(0.2749)和顶体完整数(0.31)为低等重复力。 相似文献
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对宁夏滩羊舍饲后(2005—2007年)的繁殖力状况进行了调查。结果表明,具有产双羔潜力的公羊,配种后产双羔的重复力要比具有产双羔潜力母羊产双羔的重复力高。 相似文献
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间接选择和重复力应用问题研究刘学洪（云南农大动物科技学院昆明６５０２０１）在动物育种中，利用性状间的相关的间接选择法和用重复力对动物一生生产性能的估计已被育种工作者广泛应用。然而，研究表明，间接选择和重复力的应用中存在一些尚未被注意到的、影响其应用效... 相似文献
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为了解台系杜洛克母猪重复力遗传参数在国内的适应性,充实完善台系杜洛克猪产仔数的重复力,继续选育提高杜洛克猪育种水平及经济效益。通过采用组内相关的方法,对某大型种猪企业的台系杜洛克猪1~8胎次产仔数的重复力进行估测。结果表明:台系杜洛克猪1~8胎次的平均产仔数分别为8.6头、9.65头、9.35头、9.00头、8.30头、8.80头、7.65头;台系杜洛克猪8个胎次平均产仔数为8.44头;台系杜洛克猪产仔数的重复力为0.42。 相似文献
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王金良 《青海畜牧兽医杂志》1989,(6):28-30
本文在推导家畜数量性状多次度量准确度增量(△)计算公式和分析△随性状重复力(t)和度量次数(K)变化规律的基础上,提出了两种确定数量性状适宜度量次数的标准;给出了各标准下适宜度量次数的计算公式,并列表例示了各标准若干具体要求下不同重复力性状的适宜度量次数;最后就本研究所探讨的方法及得出的结果在实际育种工作中的应用作了简要的讨论。 相似文献
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研究采用同父异母半同胞组内相关法和组内相关系数法,分别对祁连山野生动物保护中心5头塔里木马鹿种公鹿6锯三杈鲜茸重遗传力和育种值,以及9头塔里木马鹿3~9锯三杈鲜茸重的重复力进行了估测。结果表明,其遗传力为0.42,重复力为0.67(P<0.01),5头塔里木马鹿产茸量育种值等级为A128>A27>A152>A63>A77。由此说明,塔里木马鹿茸重为高遗传力和高重复力(P<0.01)性状,祁连山野生动物保护中心引入的27号和128号种公鹿种用价值较高,可以扩大使用。 相似文献
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自然光照下,阴囊大小和精液品质在一年中变异相当大,重复力不高,研究二者间的相关难以得到可靠结论。加拿大安大略州渥太华市家畜研究中心Langford 等人通过人工调整光照,使阴囊大小和精液品质变化趋于稳定,提高重复力,对阴囊大小与精液品质的相关进行了分析。11只3岁供试公绵羊,饲养在温度15℃的同一羊舍,舍内白炽灯照明,地面光照强度为160lx。起初3月每天光照16小时,促 相似文献
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东北马鹿茸重性状遗传力和重复力的估测 总被引：2，自引：0，他引：2
采用同父异母半同胞组内相关法，对乌兰坝林场７只东北马鹿种公鹿７１只后裔，１９９２～１９９７年９锯时四杈茸鲜重遗传力估测结果为０４０，属高遗传力；采用组内相关系数法，对该场７～１１锯１３只东北马鹿种公鹿锯四杈茸鲜重的重复力估测结果为０６９（Ｐ＜００１），属高重复力，为东北马鹿的纯种选育提供了主要性状的遗传参数。 相似文献
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Constable PD Ahmed AF Misk NA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):97-102
Abomasal ulceration occurs commonly in suckling calves, and the cause for the high prevalence of abomasal ulceration is unknown. We hypothesized that diet may play a role in the etiopathogenesis of abomasal ulceration. Six male dairy calves with an abomasal body cannula suckled fresh Holstein cow's milk, all milk-protein milk replacer, or combined milk- and soy-protein milk replacer twice daily at 12% of body weight/d. Abomasal luminal pH was measured every second for 24 hours by using a miniature glass pH electrode. Mean 24-hour abomasal luminal pH for all milk-protein milk replacer (3.22) and combined milk- and soy-protein milk replacer (3.27) were similar but significantly (P < .05) higher than that for cow's milk (2.77; standard error = 0.08). Both milk-replacer formulations failed to clot after the addition of chymosin, whereas cow's milk clotted within 2 minutes. The in vitro titration curve of cow's milk and all milk-protein milk replacer were similar, but different to that of combined milk- and soy-protein milk replacer. The osmolalities of all milk-protein milk replacer (375 mOsm/kg) and combined milk- and soy-protein milk replacer (410 mOsm/kg) were greater than that of cow's milk (278 mOsm/kg). The slightly lower mean abomasal luminal pH in calves suckling cow's milk, compared to milk replacer, was probably due to clotting of cow's milk, with extrusion of low pH whey, and a slower rate of abomasal emptying caused by the hyperosmolality of milk replacer. Examination of our results suggests that suckling cow's milk may increase the prevalence of abomasal ulceration by decreasing mean luminal pH, although this remains to be determined. 相似文献
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理血药治疗奶牛不孕症的试验报告 总被引：2，自引：0，他引：2
本文主要采用中兽医辩证法具体分析了奶牛发生不孕症的原因,总结了目前金华地区发生奶牛不孕症的类型,根据中兽医的辩证施治原理,分别对不同类型的奶牛不孕症进行治疗。根据对治疗结果的分析,我们认为,中药理血药在治疗奶牛不孕症的方面有着显著作用。 相似文献
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Lamb, beef and cow's milk are common causes of cutaneous adverse food reactions in dogs. The aim of this study was to identify the proteins responsible for cutaneous adverse reactions to these foods. Ten dogs with allergen-specific serum immunoglobulin (Ig)E to lamb, beef and cow's milk were included in the study. These dogs had been diagnosed with cutaneous adverse food reactions by convincing clinical history and food-elimination diet trials followed by challenge exposure. Sera were analysed by enzyme-linked immunosorbent assay with bovine proteins and SDS-PAGE immunoblots with lamb, beef and cow's milk extracts. All the dogs had specific IgE against bovine IgG, and it was the only protein in the cow's milk extract that bound IgE from the sera studied. In the lamb and beef extracts, the major allergens recognized by the specific IgE of most sera had molecular masses between 51 and 58 kDa, which were identified as phosphoglucomutase and the IgG heavy chain. Other IgE-binding proteins with molecular masses of 27, 31, 33, 37 and 42 kDa were also detected with some sera. Our results indicate that bovine IgG is a major allergen in cow's milk and hence it appears to be a source of cross-reactivity with beef and probably with lamb because of the high homology with ovine immunoglobulins. These results are similar to those found for meat allergy in humans. However, this is the first time that phosphoglucomutase has been identified as an important allergen involved in allergic reactions to lamb and beef. 相似文献
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In the past, it has been reported that neonatal diets made from unheated cow's milk were superior to those made from heated cow's milk. It was observed that piglets were equally protected from rotaviral diarrhea when they were fed diets made from either unheated milk that came from a cow immunized against porcine rotavirus or from a cow that was not immunized. Because of this observation, we examined four pools of "normal" cows' colostrum and 58 samples of "normal" cow's milk for the presence of antibody to rotavirus. All pools of colostrum, collected in four different years, had immunofluorescent antibody titers of 1:100 to rotavirus. Seventy-two percent of the samples of milk were also positive--titer no higher than 1:10. Antibodies to rotavirus were found in cow's milk at a creamery prior to but not after pasteurization. Rotaviral antibodies were detected in one out of eight brands of milk bought at the market--perhaps indicating inadequate pasteurization for this brand. These results support the proposition that, at least in part, unheated milk is superior to heated milk because unheated milk contains antibody to an ubiquitous enteropathogen like rotavirus. 相似文献
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本试验比较了木板地面和混凝土地面的牛床对奶牛产科疾病的不同影响。结果显示,新建的两种牛床奶牛产科疾病发病率,混凝土地面低于木地板,差异不显著。经过1年时间后,木板地面牛床的发病率明显高于混凝土地面牛床,差异显著(P<0.05),发病率分别为38.24%和25.00%。木板牛床患病淘汰头数明显增多,其中,胎衣不下、产后感染、乳房炎发病情况特别明显,两种地面差异极显著(P<0.01)。高温季节,发病率木地板高于混凝土地面,差异显著(P<0.05)。结果证实:减少奶牛产科疾病,混凝土地面要优于木板地面。 相似文献
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