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41.
Roundworms and flatworms that affect donkeys can cause disease. All common helminth parasites that affect horses also infect donkeys, so animals that co‐graze can act as a source of infection for either species. Of the gastrointestinal nematodes, those belonging to the cyathostomin (small strongyle) group are the most problematic in UK donkeys. Most grazing animals are exposed to these parasites and some animals will be infected all of their lives. Control is threatened by anthelmintic resistance: resistance to all 3 available anthelmintic classes has now been recorded in UK donkeys. The lungworm, Dictyocaulus arnfieldi, is also problematical, particularly when donkeys co‐graze with horses. Mature horses are not permissive hosts to the full life cycle of this parasite, but develop clinical signs on infection. In contrast, donkeys are permissive hosts without displaying overt clinical signs and act as a source of infection to co‐grazing horses. Donkeys are also susceptible to the fluke, Fasciola hepatica. This flatworm can be transmitted, via snails and the environment, from ruminants. As with cyathostomins, anthelmintic resistance is increasing in fluke populations in the UK. A number of the anthelmintic products available for horses do not have a licence for use in donkeys, and this complicates the design of parasite control programmes. As no new equine anthelmintic classes appear to be near market, it is important that the efficacy of currently effective drugs is maintained. It is important that strategies are used that attempt to preserve anthelmintic efficacy. These strategies should be based on the concept that the proportion of worms in a population not exposed to anthelmintic at each treatment act as a source of ‘refugia’. The latter is an important factor in the rate at which resistance develops. Thus, it is imperative that parasite control programmes take into account the need to balance therapy to control helminth‐associated disease with the requirement to preserve anthelmintic effectiveness.  相似文献   
42.
本试验旨在研究补饲高蛋白质、高脂肪精饲料对驴产乳量和乳成分的影响。选择 3~7岁的健康泌乳母驴 34头,设 A(12头)、B(10头)和 C(12头)3个区,共 5个处理。所有驴饲喂基础饲粮。每个区均设对照组,各试验组驴分别补饲粗蛋白质水平为 31.44%(试验 1组,A区,4头)、粗脂肪水平为 25.77%[20%棉籽油(试验 2组,A区,4头)、20%葵花籽油(试验 3组,B区,5头)、20%菜籽油(试验 4组,C区,6头)]的试验精饲料 1.5kg/d。预试期 14d,正试期14d。结果表明:1)除含 20%葵花籽油的试验精饲料外,其余试验精饲料采食量(>1300g/d)均达到预期的采食量,且未出现消化异常,表明所用精饲料适口性较好,驴对它们有较好的适应性;2)补饲含 20%棉籽油和含 20%菜籽油的试验精饲料均显著提高了驴日均产乳量(P<0.05),驴日均产乳量可达 1.5kg/d,而日均总泌乳量可达 4kg/d;3)补饲不同试验精饲料对乳成分无显著影响(P>0.05),驴乳中乳蛋白、乳糖、粗灰分含量较稳定,而乳脂含量变化非常大。总之,补饲高蛋白质、高脂肪的精饲料可提高驴产乳量,但对乳成分的影响不明显。  相似文献   
43.
Reasons for performing study: Wounds are one of the primary welfare concerns of working equids and are often related to harness or load‐bearing packs. Objectives: To identify and quantify factors associated with the presence of pack wounds in donkeys and mules working in the wood trade in the Midelt (Northern High Atlas) region of Morocco, and to compare wounds of these donkeys and mules to those working in other trades. Methods: The study population comprised equids working in the Midelt region involved in the wood trade. Comparison populations were comprised of equids working in other trades, in the same region and in Khemmiset region (lowlands of Central Morocco). Wounds were numbered and scored according to their severity. Questionnaires were used to gather data from owners, and objective data regarding the animal, berdaa (back‐pack) and load were collected. Data were analysed using multilevel uniand multivariable regression models to allow for clustering of wound sites within an equid. Results: Analysis showed an overall pack wound prevalence of 54% (n = 80/147). The most common site was the withers. Equids working in the wood trade were at increased risk of suffering pack wounds. Equids in the lowland study population were at increased risk of developing pack wounds, and donkeys were at increased risk of suffering pack wounds compared to mules both overall and within the wood trade. Other factors affecting the prevalence of wounds included the cleanliness of the berdaa and the frequency and distances of work imposed on the equid. Conclusion: Pack wounds in donkeys and mules are common in the 2 study regions of Morocco and appear to be associated with work factors including the trade the equids work in, the frequency and distances of work imposed and cleanliness of the pack. Donkeys are more susceptible than mules to developing pack wounds. Potential relevance: These results allow recommendations to be made to owners of equids that may decrease the prevalence of wounds and, therefore, improve welfare and working capability of these equids. Research is required to identify reasons for regional difference in prevalence of pack wounds in equids not working in the wood trade.  相似文献   
44.
本研究旨在对钙蛋白酶1(CAPN1)基因CDS区进行克隆及生物信息学分析,并鉴定其在广灵驴各组织中的表达量。应用生物信息学方法对广灵驴CAPN1基因CDS区进行序列分析,并对其编码蛋白的理化性质、亚细胞定位、翻译后修饰结构和蛋白结构进行预测;利用实时荧光定量PCR技术对CAPN1基因在心脏、肝脏、脾脏、肺脏、肾脏和背最长肌6种组织中的表达水平进行分析。结果显示,广灵驴CAPN1基因CDS区全长2 148 bp,可编码715个氨基酸,已提交至NCBI,登录号为:MN158194,其核酸序列与马、绵羊、牛、人、山羊、小鼠、猪的同源性分别为99.7%、92.3%、92.5%、92.0%、92.5%、85.9%和92.9%;CAPN1蛋白的分子质量为82.01 ku,理论等电点为5.59,平均疏水性为-0.374,不稳定系数为36.42,不存在跨膜区及信号肽;其编码蛋白的二级结构由无规则卷曲、α-螺旋、β-转角和延伸链组成;CAPN1基因在广灵驴的6种组织中均表达,其中在背最长肌中的表达量最丰富,其次是肝脏,在心脏中的表达最低。本研究成功克隆了广灵驴CAPN1基因CDS,并对其在不同组织中的表达量进行了分析,为进一步研究CAPN1基因在肌肉嫩度方面的表达调控功能及发展地方品种广灵驴肉制品产业提供了理论依据。  相似文献   
45.
驴肉品质及其影响因素的研究进展   总被引:2,自引:1,他引:1  
随着社会的发展和生产方式的转变,驴的役用功能逐渐消失,而驴肉功效的明确与开发利用则使驴产业在近几年有了迅猛发展。作者针对驴肉的营养特点及驴肉品质和营养价值的影响因素,如驴的品种、年龄、饲料营养、屠宰加工、驴肉质量鉴别等方面进行了综述。已有研究表明,驴肉是优质的蛋白质来源,具有高蛋白质、高必需氨基酸、高不饱和脂肪酸和低脂肪、低胆固醇、低热量的三高三低特点;对不同品种及不同屠宰年龄驴肉的营养及化学组成分析发现,不同品种驴肉的蛋白质和脂肪含量不同,不同年龄的驴肉化学组成不同,即品种和年龄对驴肉品质有很大的影响;在驴饲料中添加植物提取物可以改变饲料消化率进而使肉品质得到改善;不同部位驴肉的营养成分含量有所差别,通过对比蛋白质、脂肪、剪切力和熟肉率发现,背最长肌的食用品质高于臀肉;通过施加电刺激可加快驴肉排酸进度,改变肌纤维结构和钙蛋白酶降解,进而改善肉嫩度;使用傅里叶红外光谱分析可提高真假驴肉的辨别率。作者对驴肉肉品质及营养价值影响因素进行总结,旨在为制定规范的驴肉生产标准,保障驴肉品质提供参考依据。  相似文献   
46.
[目的]开发一种适合阿胶产业化生产的高效驴皮脱毛方法。[方法]低温条件下(4 ℃),选用1%碱性蛋白酶和1%中性蛋白酶对醒发的干驴皮开展酶解脱毛试验,比较2种酶解方法处理下驴皮的脱毛时间、脱毛率,并对脱毛过程中驴皮的气味进行评价。以1%碱性蛋白酶和1%中性蛋白酶酶解处理驴皮以及机械脱毛鲜驴皮为材料熬制阿胶,比较不同原料熬制阿胶的出胶量、出胶率、外观、气味等;测定以2种蛋白酶酶解处理的驴皮为原料熬制的阿胶质量指标,包括水分、灰分、水不溶物以及4种氨基酸含量,并与《中国药典》2015版一部中提供的相应质量标准进行对比。[结果]低温条件下(4 ℃),利用1%碱性蛋白酶(pH值=10.5)或1%中性蛋白酶(pH值=7.5)酶解处理驴皮第2天表现出脱毛效果,处理第5天醒发的干驴皮脱毛率可达90%,有臭味产生但非驴皮腐败臭味,而是脱毛过程中产生的正常气味。以1%碱性蛋白酶、1%中性蛋白酶酶解脱毛后的驴皮以及机械脱毛鲜驴皮为原料熬制阿胶,出胶量分别为113.0、109.4、129.3 g,出胶率分别为13.8%、13.1%、13.2%;2种酶解处理驴皮熬制的阿胶色红、气味芳香,与鲜驴皮熬制的阿胶相比色泽更鲜亮。2种酶解处理驴皮熬制阿胶的水分、灰分、水不溶物均符合并优于《中国药典》2015版一部中的质量标准,L-羟脯氨酸、甘氨酸、丙氨酸、L-脯氨酸含量也远高于《中国药典》2015版一部中的质量标准。[结论]低温条件下(4 ℃),1%碱性蛋白酶和1%中性蛋白酶可对醒发干驴皮进行有效酶解脱毛,且脱毛后驴皮熬制的阿胶质量符合《中国药典》2015版一部标准。  相似文献   
47.
分析不同脂肪含量驴乳产能营养素占总能量的比例及其营养价值。结果表明,平均脂肪含量0.89%~1.24%的驴乳,脂肪、蛋白质、碳水化合物(乳糖)产能占总能量的比例分别为20.25%~25.41%、12.99%~18.24%、57.46%~65.03%,符合中国营养学会推荐的我国成年人膳食中各种产能营养素能量比例的要求;脂肪含量较高的驴乳,总能量、人体必需脂肪酸和脂溶性维生素含量较高,各种产能营养素占总能量的比例更适合人体代谢和健康需要,具有较高的营养价值。  相似文献   
48.
旨在建立驴骨胶原肽的制备方法,并对其分子量进行检测。以牛血清白蛋白为对照品,建立多肽含量和OD650 nm值的标准曲线方程;模拟人工胃液、肠液环境,以驴骨胶原肽一级、二级酶解产物多肽含量为评价指标,在筛选胃蛋白酶和胰蛋白酶最佳酶解时间和加酶量的基础上,采用二级生物酶解技术制备驴骨胶原肽;应用SDS-PAGE法对制备的驴骨胶原肽的分子量进行检测。结果表明,建立的多肽含量和OD650 nm值标准曲线方程为:y=0.163 9x-0.149 6,R2=0.998 9;应用胃蛋白酶进行一级酶解驴骨胶原肽的最适反应条件为:pH值在2.5~3.0,加酶量2.0%、酶解时间2.0 h;应用胰蛋白酶进行二级酶解驴骨胶原肽的最适反应条件为:pH值在7.5~8.0,加酶量2.0%、酶解时间2.5 h;经SDS-PAGE法检测,根据上述最适反应条件制备的驴骨胶原肽的分子量在10 kDa左右。研究结果为开发适合人体吸收分子量的驴骨胶原肽原料以及后续产品的研发提供了技术参考。  相似文献   
49.
ObjectivesTo evaluate the cardiorespiratory and biochemical effects of ketamine-propofol (KP) or guaifenesin-ketamine-xylazine (GKX) anesthesia in donkeys.Study designProspective crossover trial.AnimalsEight healthy, standard donkeys, aged 10 ± 5 years and weighing 153 ± 23 kg.MethodsDonkeys were premedicated with 1.0 mg kg?1 of xylazine (IV) in both treatments. Eight donkeys were administered ketamine (1.5 mg kg?1) and propofol (0.5 mg kg?1) for induction, and anesthesia was maintained by constant rate infusion (CRI) of ketamine (0.05 mg kg?1 minute?1) and propofol (0.15 mg kg?1 minute?1) in the KP treatment. After 10 days, diazepam (0.05 mg kg?1) and ketamine (2.2 mg kg?1) were administered for induction, and anesthesia was maintained by a CRI (2.0 mL kg?1 hour?1) of ketamine (2.0 mg mL?1), xylazine (0.5 mg mL?1) and guaifenesin (50 mg mL?1) solution. Quality of anesthesia was assessed along with cardiorespiratory and biochemical measurements.ResultsAnesthetic induction took longer in GKX than in KP. The induction was considered good in 7/8 with KP and in 6/8 in GKX. Anesthetic recovery was classified as good in 7/8 animals in both treatments. Xylazine administration decreased heart rate (HR) in both treatments, but in KP the HR increased and was higher than GKX throughout the anesthetic period. Respiratory rate was higher in GKX than in KP. PaO2 decreased significantly in both groups during the anesthetic period. Glucose concentrations [GLU] increased and rectal temperature and PCV decreased in both treatments. Arterial lactate [LAC] increased at recovery compared with all time points in KP. [GLU] and calcium were higher in GKX than in KP at recovery.Conclusion and clinical relevanceThese protocols induced significant hypoxemia but no other cardiorespiratory or metabolic changes. These protocols could be used to maintain anesthesia in donkeys, however, they were not tested in animals undergoing surgery.  相似文献   
50.
疆岳驴体重和体尺性状的相关和回归分析   总被引:1,自引:0,他引:1  
疆岳驴是我国优良的乳肉兼用地方品种,为了加快对疆岳驴的选育、提纯复壮和保种速度,本研究选择101头疆岳驴进行体重和体尺测定,并应用R语言(2.15.0)进行相关和回归分析。结果表明,年龄对疆岳驴的体高、胸围和体重影响极显著(P<0.001),对体长和管围影响显著(P<0.05),其中1~3岁年龄组的体高、体长、胸围、管围和体重值最大,并且1~3岁公驴的体高、管围和体重显著优于母驴(P<0.05)。疆岳驴的体重与体尺性状有极显著的相关关系(P<0.001),通过建立最优回归方程表明,影响体重的重要性状依次为胸围、体高和体长。建议疆岳驴在选育、提纯复壮和保种时应加大对胸围、体高和体长的选择力度,同时参照最优回归模型可以获得较好的效果。  相似文献   
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