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“母犊素”是一种生殖生理调控的激素类药品。喀什地区2004～2005年在6个县的68个冷配站实施“母犊素”的推广使用,目的在于改善冷配母牛母犊出生率偏低的现象,提高农牧民参与黄牛改良的积极性。项目实施参试牛只达3 500头,随机调查产犊头数1 618头,母犊率平均达到58．90％,比未使用“母犊素”处理的母牛产母犊率42．66％净提高16．24％,相对提高38．07％。试验证明,用“母犊素”处理配种母牛,不仅能大幅度提高母犊出生率,还能提高母牛的部分繁殖性能,值得在黄牛改良中推广应用。 相似文献
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在果洛地区挑选成年带犊哺乳母牛7头和不带犊母牛5头，跟踪测定体重，结果：带犊母牛体重由春季到秋季增加18．97kg，由秋季至翌年春末体重减少了15．57kg，观测期内体重增加了3.40kg；不带犊母牛由春季到秋季体重增加65.08kg，由秋季至翌年春末体重减少51.43kg，观测其内增重13.65kg。 相似文献
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<正>牛的增产赖于母牛繁殖率的提高。目前无法缩短怀孕期的情况下,要尽量缩短产犊间隔,如乳牛要求产犊间隔12个月,1年中除产犊后2个月空怀外,要尽量提高母牛受胎率,使空怀母牛及时受胎,缩短产犊间隔。影响母牛受胎的因素很多,如母牛的营养、健康状况、输精时间等。为了提高母牛的受胎率,应做好以下工作。 相似文献
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本文对３７６头在１９７８～１９９５年间产犊的么拉、尼里、杂种奶水牛的原始资料按产犊性别、产后首次发情天数、情期受胎率、下胎受孕情期数等四项指标进行了统计、分析。结果表明：产犊性别对尼里母牛的产后首次发情有显著影响（Ｐ＜０．０５），对么拉、杂种母牛的下胎受孕情期数有显著影响（Ｐ＜０．０５）；产公犊么拉、尼里母牛的第一情期受胎率比产母犊母牛分别低１２．４％和２０．０％，而产公犊杂种母牛的第一情期受胎率比产母犊母牛高１０．０％。产后３０天内发情母牛的第一情期受胎率最低，为３３．３％。产后６０～９０天内发情母牛的最高，为５０．８％ 相似文献
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①促进母牛白天产犊。母牛产犊集中在4～5月份,且多数在夜间,照料不周牛产犊时间过长、产道感染、生殖道损伤等病。同时也造成新生犊时间过长、产道感染、生殖道损伤等病。同时也造成新生犊牛假死、孱弱或感冒等症的发生。实践证明,让母牛夜间采食,可促使白天产犊。目前,普遍做法是让妊娠最后一个月的母牛在夜间采食可促使70%以上的母牛在白天产犊。白天产犊便于观察,有利于助产,可避免冬天不良因素的影响,减少产科病,提高产犊成活率。②实行药物保胎。对正常母牛配种后肌肉注射VE500mg或在输精后再将0.5%新斯的明溶液2mL注入子宫颈内,可… 相似文献
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Yuko Emoto Katsuhiko Yoshizawa Nobuaki Shikata Airo Tsubura Yasushi Nagasaki 《Journal of toxicologic pathology》2016,29(1):45-47
Sodium hydroxide is a strongly corrosive alkali. We describe herein a case of suicide by ingestion of sodium hydroxide. A man in his 80s was found dead with a mug and a bottle of caustic soda. Macroscopically, liquefaction and/or disappearance of esophagus, trachea and lung tissue and a grayish discoloration of the mucosa of the stomach were seen along with blackish brown coloration of the skin, mouth, and oral cavity. The contents of the gastrointestinal tract showed a pH level of 7–8 on pH indicator strips. Histopathologically, liquefactive necrosis of remnant lung tissue and the stomach were seen. As biological reactions such as vasodilatation and inflammation were not detected in these organs, only a short number of hours must have passed between ingestion and death. This human case provides valuable information concerning the direct irritation induced by systemic exposure to corrosive substances. 相似文献
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N. Moulin M. Schramme I. François G. Castelijns S. Belluco 《Equine Veterinary Education》2020,32(3):137-143
This report describes a rare case of squamous cell carcinoma (SCC) in a 10-year-old Shetland pony. The pony was presented for evaluation of a chronic, ulcerating mass of the foot associated with a nonweightbearing lameness of the right forelimb. Foot radiographs revealed an aggressive bone lesion with severe osteolysis of the distal phalanx. Amputation of the digit was performed under general anaesthesia at the level of the metacarpophalangeal joint using a palmar flap technique and a transfixation cast for protection of the stump. Avascular necrosis, infection and dehiscence of the stump occurred 3 weeks later and a second amputation was performed at the level of the proximal third of the third metacarpal bone. Histopathology revealed a squamous cell carcinoma. After healing of the stump, a prosthesis was fitted to the limb for improved ambulation of the pony. Two years after the amputation, telephone follow-up with the referring veterinarian and the owner, revealed that the pony was healthy and able to go out daily in a paddock with its prosthesis. SCC represents an unusual indication for limb amputation. Successful outcome is rarely reported in horses. 相似文献
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干旱胁迫对4种决明属植物光合作用和叶绿素荧光特性的影响 总被引：4，自引：0，他引：4
以4种决明属植物草决明(Cassia obtusifolia)、望江南(C.occidentalis)、伞房决明(C.corymbosa)、双荚决明(C.bicapsularis)为材料,采用盆栽控水试验,设置轻度干旱、重度干旱和正常灌水处理,研究了干旱胁迫对4种决明属植物的叶绿素含量、光合作用参数和叶绿素荧光特性的影响。结果显示,1)干旱胁迫导致4种决明属植物的叶绿素含量下降,望江南的下降幅度最小,说明望江南在水分减少的情况下仍具有较高的光合作用能力,伞房决明的叶绿素含量在3种处理下都趋于最高水平,表明伞房决明光能吸收、转换和传递能力较强;2)干旱胁迫导致4种决明属植物气孔导度(Gs)降低,气孔限制值(Ls)升高,伴随着胞间CO2浓度(Ci)降低,净光合速率(Pn)下降,表明是气孔因素造成的,此后,除草决明外其它3种植物的Ci均升高,Ls均下降,这是非气孔因素造成的;在干旱胁迫下望江南具有较高的光合速率,伞房决明具有相对较高的气孔开放度;3)干旱胁迫导致4种决明属植物的最大荧光(Fm)和光化学效率(Fv/Fm)下降,初始荧光(Fo)上升,表明PSⅡ结构受到破坏或者植物进行了热耗散。光化学淬灭系数(qP)和电子传递速率(ETR)下降,而非光化学淬灭系数(NPQ)上升,说明干旱胁迫对PSⅡ造成伤害,但其能够有效地避免或减轻因PSⅡ吸收过多光能而引起的光抑制和光氧化。望江南表现的最稳定,说明望江南具有较强的抗旱性。 相似文献
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The emergence of canine parvovirus (CPV) represents a well-documented example highlighting the emergence of a new virus through cross-species transmission. CPV emerged in the mid-1970s as a new pathogen of dogs and has since become endemic in the global dog population. Despite widespread vaccination, CPV has remained a widespread disease of dogs, and new genetic and antigenic variants have arisen and sometimes reached high frequency in certain geographic regions or throughout the world. Here we review our understanding of this emergence event and contrast it to what is known about the emergence of a disease in mink caused by mink enteritis virus (MEV). In addition, we summarize the evolution of CPV over the past 30 years in the global dog population, and describe the epidemiology of contemporary parvovirus infections of dogs and cats. CPV represents a valuable model for understanding disease emergence through cross-species transmission, while MEV provides an interesting comparison. 相似文献
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从一个免疫失败鸡场中分离到一株鸡传染性法氏囊病病毒野毒株,命名为SD株.经血清学试验、鸡胚接种、病毒形态观察等证实了分离物为鸡传染性法氏囊病病毒(IBDV).测定病毒效价ELD50达到10-6.5/0.2 mL;动物回归试验表明,该SD株接种4周龄鸡后引起鸡群发病率为100%,病死率达85%,剖检可见法氏囊呈"紫葡萄样... 相似文献
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为明确退化草地恢复过程中草地植被地上生物量时间稳定性变化及影响因素,以天山北坡中段蒿类荒漠草地为对象,采用野外取样和室内分析的方法,测算了封育年限间(2,4,6 a)群落地上生物量时间稳定性及物种异步性等,结果表明：封育2,4,6 a蒿类荒漠草地地上生物量较对照依次提高38.83%,136.26%,87.21%(P<0.05)。封育2 a蒿类荒漠草地群落地上生物量时间稳定性较对照增加38.36%(P<0.05),而封育4,6 a则变化不显著;封育4,6 a蒿类荒漠草地物种丰富度较对照分别降低46.15%,15.93%(P<0.05),物种异步性降低20.13%,17.52%(P<0.05)。物种丰富度与地上生物量时间稳定性无显著相关,但物种异步性及优势种时间稳定性对群落地上生物量时间稳定性有正向促进作用。因此,封育有利于退化蒿类荒漠草地植物地上生物量的恢复,物种异步性和优势物种时间稳定性是驱动群落地上生物量时间稳定性的重要因子。 相似文献
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牛的性状有一类是由单个或少数几个基因座所决定的,其表现不受或很少受环境因素的影响,且表型变异为间断分布,这就是牛的质量性状。本文介绍了牛质量性状特点及改良中的遗传规律、改良方法与途径,对毛色、角、遗传缺陷等质量性状重点进行了分析。 相似文献
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Braun JP Concordet D Lyazrhi M Lefebvre HP Toutain PL 《Veterinary research communications》2000,24(1):17-24
The specificity of a diagnostic test for a given disease, i.e. the percentage of true negatives, can be calculated from either the results from a group of healthy animals or possibly from a group which also contains diseased animals which are free of the particular disease for which the test has been performed. The specificity may be much lower in the latter case and the predictive value of positives thus greatly reduced. In the example of creatine kinase being used for the diagnosis of muscle diseases in dogs, the specificity at the thresholds of 105 and 150 U/L (upper limits of the 95% and 99.7% interquantiles) decreased from 0.98 and 1.0 to 0.66 and 0.78, respectively. 相似文献
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非编码RNA(non-coding RNA,ncRNA)是指从基因组上转录而来,不编码蛋白质,但在RNA水平上能行使一定生物学功能的RNA。非编码RNA的种类较多,种类的不同造成功能的差异。毛囊是绒山羊皮肤特殊的附属物,位于皮肤的真皮层,发生于绒山羊胚胎期。由于真皮细胞和上皮细胞间的信号分子传递,使其发育呈周期性变化,历经生长期、退行期和休止期。近年来,有关ncRNA在绒山羊毛囊发育中作用报道较多。文章就其中的微小RNA(miRNA)、长链非编码RNA(lncRNA)及环状RNA(circRNA)的生物发生及其在绒山羊毛囊发育中的作用机制进行了归纳、总结。miRNA是真核生物中存在的一种长18~25 nt的ncRNA分子,可通过与靶信使核糖核酸mRNA特异结合,抑制转录后基因表达。在绒山羊毛囊发育中,miRNA通过抑制相关基因及相关信号通路中关键分子的表达而调控毛囊的发育周期以及毛囊的再生能力。lncRNA是长度超过200 nt的ncRNA,经过剪接,具有polyA尾巴与启动子结构,在绒山羊毛囊发育中能促进毛囊细胞增殖与分化,通过调控基因的靶向表达与多种信号通路互作调节毛囊发育及绒毛生长的周期活动。circRNA是与传统的线性RNA不同的封闭环状RNA,含有许多miRNA结合位点,在绒山羊毛囊发育与绒毛生长中起miRNA分子海绵的作用,即通过miRNA的介导,调控靶基因的表达,促进毛囊干细胞向次级毛囊分化,进而解除与毛囊发育与绒毛生长相关的miRNA对其靶基因的抑制作用提高靶基因的表达水平。笔者通过对miRNA、lncRNA及circRNA的研究进行综述,以期为构建毛囊生长发育的分子调控网络及深入探讨绒山羊毛囊发育的调控机制提供借鉴,为今后更好地利用现代分子生物学技术改善绒毛品质提供理论依据。 相似文献
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Influences of different dietary contents of macrominerals on the availability of trace elements in horses 
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下载免费PDF全文 L.‐T. Neustädter J. Kamphues C. Ratert 《Journal of animal physiology and animal nutrition》2018,102(2):e633-e640
In this study, influences of a reduced macromineral intake on the trace element metabolism in horses at maintenance were investigated. Background of this study is the revised recommendation on the macromineral supply for horses (GfE 2014 ). Balance studies on three adult pony geldings with body weights of 405 / 348 / 384 kg were performed to obtain data on apparent digestibility (aD), retention and serum concentrations of different trace elements (Cu, Zn, Se) at different dietary macromineral levels. A mineral supplement or a complementary feed—with a reduced macromineral content—was added to a hay‐based diet (daily 5.5 kg hay per animal, split in three servings a day), beside distilled water was offered. The diets were offered one after the other in a way that all ponies had the same sequence of treatments. The native macromineral contents of the daily offered amount of hay already surpassed the new recommendations whereas dietary trace elements needed to be supplemented. There were no statistically significant differences (p ≤ .05) concerning the aD of copper, zinc and selenium comparing the diets with and without macromineral supplementation. Serum levels of these three trace elements were not affected by the different macromineral content of the diet. Results of this study, based on a 22‐day feeding period for each treatment, indicate that a macromineral supplementation of a hay‐based diet for adult horses at maintenance was not necessary. However, no negative effects of added macrominerals on the trace element metabolism occurred in this study. 相似文献