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奶牛的管理、营养、产量和基因选择都与其生育能力有直接关系.从体况评分、营养信号、内分泌和生殖器官等方面综述了高产奶牛繁殖障碍的起因和调控因素. 相似文献
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B Serrano F López-Gatius P Santolaria S Almería I García-Ispierto G Bech-Sabat J Sulon NM de Sousa JF Beckers JL Yániz 《Reproduction in domestic animals》2009,44(4):600-605
This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March–November vs cool period, December–February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period. 相似文献
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Recent Developments in Oestrous Synchronization of Postpartum Dairy Cows with and without Ovarian Disorders 总被引:1,自引:0,他引:1
This report reviews the most recent developments in prostaglandin‐based oestrous synchronization programmes for postpartum dairy cows and addresses the efficiency of controlled breeding protocols based on such developments for cows with abnormal ovarian conditions. A double prostaglandin protocol applied 11–14 days apart seems to be capable of bringing most cows to oestrus. Because of varying oestrus onset times, improved conception rates are obtained following artificial insemination (AI) at detected oestrus rather than fixed‐time AI in prostaglandin‐treated cows. The administration of oestradiol or human chorionic gonadotrophin, or both these hormones, after prostaglandin treatment, improves the synchrony of oestrus yet does not enhance the conception rate. Progesterone‐based treatments for oestrous synchronization are considered the most appropriate for non‐cyclic or anoestrous postpartum dairy cows; prostaglandin alone being ineffective because of the absence of a mature corpus luteum in these cows. Improved oestrus synchrony and fertility rate have been reported using short‐term progesterone treatment regimes (7–9 days) with or without oestradiol benzoate combined with the use of a luteolytic agent given 1 day before, or at the time of, progesterone withdrawal. The ovulation synchronization (Ovsynch) protocol, based on the use of gonadotrophin releasing hormone and prostaglandin, was developed to coordinate follicular recruitment, CL regression and the time of ovulation. This protocol allows fixed time insemination and has proved effective in improving reproductive management in postpartum dairy cows. However, timed AI following Ovsynch seems to have no beneficial effects in heifers, because of an inconsistent follicle wave pattern, and in anoestrous cows, given their lack of prostaglandin responsive CL. To date, there are several prostaglandin based, fixed‐time insemination oestrous synchronization protocols for use in early postpartum dairy cows with ovarian disorders such as ovarian cysts and acyclicity. 相似文献
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大豆小肽的生理功能特性及在奶牛生产中的应用 总被引:1,自引:1,他引:0
大豆蛋白质经过适当的处理.可分解释放出分子量不等的肽。包括生物活性肽。这些小肽为2-5个AA残基以肽键相连的短链.液相色谱显示其分子量在1000D以下,主要出峰位置在分子量300-700D的范围内(葛文光,1996)。生物活性肽(BAP)一般分子量较小,构象比较松散,其AA组成与大豆蛋白质基本相同.但具有多种重要的生物学活性,能调节生物机体的生理活动.具有促进脂肪代谢、抗氧化、降血压、提高免疫力、消除疲劳、促进微生物发酵等作用(程丽娟,2004)回,且在体内降解,不会造成体内存积,能作为肠可吸收蛋白质源,也能作为功能添加剂,可有效地提高畜禽的生产力和饲养效率。 相似文献
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The High-producing Dairy Cow and its Reproductive Performance 总被引:2,自引:0,他引:2
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乳房炎奶牛部分血液生化指标的变化 总被引:4,自引:2,他引:4
随机选取21头临床健康荷斯坦奶牛(CMT检测呈阴性)、19头隐性乳房炎奶牛(CMT检测呈阳性)、33头临床型乳房炎奶牛,分别于颈静脉采血,分离血清,测定总蛋白(TP)、白蛋白(ALB)、球蛋白(GLOB)、碱性磷酸酶(ALP)、N-乙酰-β-D-氨基葡萄糖苷酶(NAG)以及免疫球蛋白IgA、IgM、IgG等生化指标.结果表明,临床型乳房炎奶牛血清中碱性磷酸酶、N-乙酰-β-D-氨基葡萄糖苷酶的活性显著高于健康奶牛和隐性乳房炎奶牛(P<0.01或P<0.05),临床型奶牛血清中免疫球蛋白Isa、IgM、IgG的含量显著高于健康奶牛(P<0.01或P<0.05).隐性乳房炎奶牛血清中碱性磷酸酶、N-乙酰-β-D-氨基葡萄糖苷酶的活性和免疫球蛋白IgA、IgM、IgG的含量高于健康奶牛,但差异不显著(P>0.05);3组奶牛血清总蛋白、白蛋白和球蛋白含量均无显著性差异(P>0.05). 相似文献
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奶牛常用粗饲料的瘤胃降解规律 总被引:2,自引:0,他引:2
本试验旨在研究 2种苜蓿[黑龙江公农 1号苜蓿、美国安德森(Anderson)一级苜蓿]、黑龙江 2种含杂量不同羊草(杂草率分别为 10%、34%)、全株玉米青贮、玉米秸秆青贮和玉米秸秆共 7种粗饲料的瘤胃降解特性。试验选用 8头装有永久性瘤胃瘘管的荷斯坦奶牛,采用尼龙袋法评定其干物质(DM)、粗蛋白质(CP)和中性洗涤纤维(NDF)的瘤胃降解率和有效降解率。结果表明,美国安德森一级苜蓿、全株玉米青贮和黑龙江公农 1号苜蓿三者 72hDM 降解率差异不显著(P>0.05),并显著高于其他 4种粗饲料(P<0.05),而 DM有效降解率以美国安德森一级苜蓿最高,并与依次降低的黑龙江公农 1号苜蓿、全株玉米青贮和玉米秸秆青贮差异显著(P<0.05),羊草与玉米秸秆的 DM有效降解率显著低于其他粗饲料(P<0.05)。72hCP降解率及有效降解率以美国安德森一级苜蓿最高,且降解率与依次降低的黑龙江公农 1号苜蓿、全株玉米青贮、玉米秸秆青贮、杂草率为 10%的羊草、玉米秸秆和杂草率为 34%的羊草间差异显著(P<0.05)。全株玉米青贮、玉米秸秆青贮 72hNDF降解率显著高于其他粗饲料(P<0.05);而有效降解率以 2种苜蓿较高,其次为玉米秸秆青贮与全株玉米青贮;降解率和有效降解率最低的均为杂草率为 34%的羊草。因此,从 7种粗饲料在奶牛瘤胃的消化特性来看:1)美国安德森一级苜蓿营养价值最高,杂草率为 34%的羊草与玉米秸秆营养价值较低;2)羊草的品质受杂草率的影响;3)青贮能改善玉米秸秆的品质。 相似文献
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本试验旨在研究2种苜蓿[黑龙江公农1号苜蓿、美国安德森( Anderson)一级苜蓿]、黑龙江2种含杂量不同羊草(杂草率分别为10%、34%)、全株玉米青贮、玉米秸秆青贮和玉米秸秆共7种粗饲料的瘤胃降解特性.试验选用8头装有永久性瘤胃瘘管的荷斯坦奶牛,采用尼龙袋法评定其干物质(DM)、粗蛋白质(CP)和中性洗涤纤维(NDF)的瘤胃降解率和有效降解率.结果表明,美国安德森一级苜蓿、全株玉米青贮和黑龙江公农1号苜蓿三者72 h DM降解率差异不显著(P>0.05),并显著高于其他4种粗饲料(P<0.05),而DM有效降解率以美国安德森一级苜蓿最高,并与依次降低的黑龙江公农1号苜蓿、全株玉米青贮和玉米秸秆青贮差异显著(P<0.05),羊草与玉米秸秆的DM有效降解率显著低于其他粗饲料(P<0.05).72 h CP降解率及有效降解率以美国安德森一级苜蓿最高,且降解率与依次降低的黑龙江公农1号苜蓿、全株玉米青贮、玉米秸秆青贮、杂草率为10%的羊草、玉米秸秆和杂草率为34%的羊草间差异显著(P<0.05).全株玉米青贮、玉米秸秆青贮72 h NDF降解率显著高于其他粗饲料(P<0.05);而有效降解率以2种苜蓿较高,其次为玉米秸秆青贮与全株玉米青贮;降解率和有效降解率最低的均为杂草率为34%的羊草.因此,从7种粗饲料在奶牛瘤胃的消化特性来看:1)美国安德森一级苜蓿营养价值最高,杂草率为34%的羊草与玉米秸秆营养价值较低;2)羊草的品质受杂草率的影响;3)青贮能改善玉米秸秆的品质. 相似文献
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S Pyörälä 《Reproduction in domestic animals》2008,43(S2):252-259
Transition from the dry period to lactation is a high risk period for the modern dairy cow. The biggest challenge at that time is mastitis. Environmental bacteria are the most problematic pathogens around parturition. Coliforms are able to cause severe infections in multiparous cows, and heifers are likely to be infected with coagulase-negative staphylococci. During the periparturient period, hormonal and other factors make the dairy cows more or less immunocompromised. A successful mastitis control programme is focused on the management of dry and calving cows and heifers. Clean and comfortable environment, proper feeding and adequate supplementation of the diet with vitamins and trace elements are essential for maintaining good udder health. Strategies which would enhance closure of the teat canal in the beginning of the dry period and would protect teat end from bacteria until the keratin plug has formed decrease the risk for mastitis after calving. Dry cow therapy has been used with considerable success. Yet, a selective approach could be recommended rather than blanket therapy. Non-antibiotic approaches can be useful tools to prevent new infections during the dry period, in herds where the risk for environmental mastitis is high. Vaccination has been suggested as a means to support the immune defence of the dairy cow around parturition. In some countries, implementation of Escherichia coli core antigen vaccine has reduced the incidence of severe coliform mastitis after calving. 相似文献