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81.
蒙古驴微卫星多态性分析   总被引:2,自引:1,他引:1  
利用10对微卫星引物对94头蒙古驴进行DNA多态性分析,主要研究了有效等位基因数、多态信息含量和杂合度等指标.结果表明:10个微卫星位点中,HTG7、HTG10、AHT4、HTG6、HMS6、HMS3共6个位点具有高度多态性(PIC>0.5),HMS7位点具有中度多态性,其等位基因数、有效等位基因数、多态信息含量、杂合度最低.其余3个微卫星座位(HMS1,HTG4和HMS5)为单态,没有多态性.总体上看,蒙古驴的遗传多态性很高,有利于遗传资源的开发与利用.  相似文献   
82.
不同精料水平对新疆驴利用稻草日粮的影响   总被引:1,自引:0,他引:1  
本实验选用3头雄性健康新疆驴为实验动物,体重132±10Kg,3~4周岁,采用全收粪消化实验方法,分三期进行,研究在3种精料水平(0g/d、400g/d、800g/d)下新疆驴对稻草日粮的利用率。实验结果表明:400g精料组的干物质采食量为3813±284g/d,较0g精料组的3015±265g/d有显著提高(P〈0.01),较800g精料组3490±238g/d有显著提高(P〈0.05),干物质消化率随着精料水平的增加有增加趋势(P〉0.05)。400g和800g精料组的粗蛋白采食量、消化率分别为281±50g/d、53.5±5.7%和357±55g/d、59.2±2.2%,都分别显著高于0g精料组的149±42g/d采食量和36.3士3.8%的消化率(P〈0.01)。400g精料组NDF和ADF的采食量都较其它两组有所提高(P〈O.05),而三组间的消化率无明显差异(P〉0.05)。800g料组磷的采食量、消化率和能量的消化率分别为8.1±2.8g/d、30.8±4.8%和53.5±3.5%,分别较0g精料组有显著提高(P〈O.05),与400g精料组间无明显差异(P〉0.05)。新疆驴在日喂400g精料下能够较好的利用稻草日粮。  相似文献   
83.
旨在研究驴乳中溶菌酶活性与母驴泌乳阶段和处理温度之间的关系.本研究首先取新鲜牛、羊和驴乳进行乳中溶菌酶活性的比较.为了探究泌乳阶段和泌乳水平对乳中溶菌酶活性的影响,将4~9岁母驴根据日均产奶量水平分为低(400 g以下)、中(400~1 000 g)、高(1 000 g以上)3组,每组随机挑选3头共9头试验动物,连续观...  相似文献   
84.
驴生长激素基因的克隆与分析   总被引:1,自引:0,他引:1  
 【目的】克隆驴生长激素基因DNA和cDNA的全序列,分析其序列和cDNA编码的蛋白序列特征及其在不同物种中的遗传差异。【方法】根据不同物种同一基因序列的同源性比对结果设计引物,应用RT-PCR和PCR 技术克隆基因,用生物信息学方法对获得的DNA和cDNA及推定的氨基酸序列进行分析。【结果】从驴肝组织和血液中分别得到驴GH基因全序列1 928 bp和包括完整的编码区的cDNA序列706 bp,两者序列比对后证明驴GH基因DNA序列由5个外显子和4个内含子组成,编码216个氨基酸的GH前体蛋白,其中包括26个氨基酸的信号肽和190个氨基酸的成熟肽。序列比较结果表明,驴GH基因的序列与马同源性最高,启动子不是哺乳动物的典型TATA盒,而是CATA盒,该基因在进化过程中是保守的。【结论】从驴肝组织和血液中克隆了GH基因DNA和cDNA,DNA序列在1 267位的C→G可能影响到驴和马生长发育的差异,为下一步驴GH基因的表达调控、进化和多态性分析奠定了基础。  相似文献   
85.
摘要:【研究目的】为了研究德州驴生长激素基因的多态性及其对生长发育的影响,【方法】根据不同物种同一基因序列的同源性比对结果,在线设计引物,应用PCR 技术克隆基因,用生物信息学方法对获得的德州驴GH基因DNA序列及其推定cDNA、氨基酸序列进行分析。【结果】结果表明德州驴GH基因DNA序列约为1928bp,包含完整的5个外显子和4个内含子,德州驴GH基因DNA序列与德宝矮马67、蒙古马、猪、牛、绵羊和人GH基因序列的同源性分别为98.8%、98.2%、79.4%、68.3%、70.9%和68.3%,cDNA编码的氨基酸序列同源性分别为99.5%、98.6%、97.2%、89.8%、88.9%和68.4%。【结论】表明GH基因在进化上非常保守。  相似文献   
86.
A mature donkey was presented for evaluation of a forelimb lameness and presence of a large mass on the left forelimb distal to the elbow joint. Clinical examination, radiographs and cytological examination of ultrasound‐guided fine needle aspirates of the mass led to a presumptive diagnosis of osteosarcoma. The donkey was subsequently subjected to euthanasia. Post mortem examination confirmed the diagnosis of osteosarcoma in the proximal radius with expansion of the mass through the ulnar cortex and metastases to liver and regional lymph nodes, areas of metastasis previously unreported in the equine literature.  相似文献   
87.

Objective

To assess and compare the sedative and antinociceptive effects of four dosages of dexmedetomidine in donkeys.

Study design

Randomized, controlled, crossover, Latin-square, blinded study.

Animals

Six healthy, castrated, adult, standard donkeys.

Methods

Dexmedetomidine (2, 3, 4 and 5 μg kg?1; D2, D3, D4 and D5), acepromazine (0.1 mg kg?1) and saline were administered intravenously to each donkey and a 1 week interval was allowed between successive trials on each animal. Sedation scores (SS) and head heights above ground (HHAG) were used to assess sedation and mechanical nociceptive threshold (MNT) testing to assess antinociception over 120 minutes post-treatment. Areas under the curve (AUC) for 0–30, 30–60 and 60–120 minutes were computed to compare the effect of treatments.

Results

SS-AUC0–30 values were larger for D4 and D5, and SS-AUC30–60 values were larger for D5 than for saline. All dexmedetomidine treatments produced lower HHAG-AUC0–30 and HHAG-AUC30–60 values, and acepromazine produced lower HHAG AUC60–120 values than did saline. For MNT, D3, D4 and D5 increased AUC0–30 and AUC30–60 values compared with saline and also AUC0–30 values compared with D2 and acepromazine. Smaller MNT-AUC30–60 values were obtained with D2 than with D4 and D5, with D3 than with D5, and with acepromazine than with D4 and D5.

Conclusions and clinical relevance

Dexmedetomidine induced sedation and dosage-dependent mechanical antinociception. Larger dexmedetomidine dose rates were required to induce antinociception than sedation. Furthermore, the antinociception induced by dexmedetomidine was of shorter duration than its sedation. For minor painful procedures on standing donkeys, D5 may be clinically useful to provide sedation and analgesia.  相似文献   
88.
89.
A 6‐month‐old donkey presented with recumbency after rearing and falling over. A presumptive diagnosis of traumatic brain injury secondary to a skull fracture was made following the clinical examination, although a fracture could not be identified on radiography. To provide a definitive diagnosis, for planning any surgical intervention and to obtain prognostic information, computed tomography and magnetic resonance imaging were performed. An occipital depression skull fracture with secondary haemorrhage and oedema of the cerebellum and brainstem were identified. The imaging findings were confirmed at pathological examination. This report describes the imaging features of a traumatic brain injury in a donkey.  相似文献   
90.
Oligopeptide transporter 2 (PepT2) is an important transporter of oligopeptides. In the present study, we describe the molecular cloning, tissue distribution and functional characterization of a donkey (Equus asinus) PepT2. The cloned cDNA sequence was 2202 bp at full length, encoding a 733 amino acid peptide with a molecular weight of 81.9 kDa and a theoretical pI of 8.92. Bioinformatics analysis showed that the deduced peptide sequence possessed all the characteristic features of PepT2. The expression of PepT2 in the kidney and lung was significantly higher than that observed in the ileum, duodenum, jejunum, spleen, liver, heart and stomach. Functional characterization by heterologous expression in Chinese hamster ovary cells showed that the uptake of β-Ala-Lys-N-7-amino-4-methylcoumarin-3-acetic acid (β-Ala-Lys-AMCA) by donkey PepT2-Chinese hamster ovary cells was dependent on time, pH and substrate concentration, with a low Km value of 91.51 ± 14.14 μM and a maximum velocity of 41.37 ± 2.193 pmol/min/mg protein. In the present study, for the first time, the expression and functional characteristics of donkey PepT2 were evaluated, the results of which provide new insights and a better understanding of its crucial role in oligopeptide transport in donkeys.  相似文献   
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