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1.
The coronavirus disease 2019 (COVID-19) pandemic has now affected over 72.5 million people worldwide, with nearly 1.6 million deaths reported globally as of December 17, 2020. SARS-CoV-2 has been implicated to have originated from bats and pangolins, and its intermediate animal hosts are being investigated. Crossing of the species barrier and exhibition of zoonosis have been reported in SARS-CoV-2 in farm (minks), domesticated (cats and dogs), and wild animals (tigers, puma, and lions). Recently, the rapid spread of SARS-CoV-2 infection was reported in mink farms, which led to the death of a myriad minks. The clinical and pathological findings of SARS-CoV-2 infection and the rapid animal-to-animal transmission in minks are almost similar to the findings observed in patients with COVID-19. Additionally, the rapid virus transmission among minks and the associated mutations resulted in a new mink-associated variant that was identified in both minks and humans, thereby providing evidence of mink-to-human transmission of SARS-CoV-2. The new mink-associated SARS-CoV-2 variant with a possible reduced sensitivity to neutralizing antibodies poses serious risks and is expected to have a direct effect on the diagnostic techniques, therapeutics, and vaccines that are currently under development. This article highlights the current evidence of SARS-CoV-2 infection in farmed minks, and provides an understanding of the pathogenesis of COVID-19 in minks and the associated zoonotic concerns of SARS-CoV-2 transmission from minks to humans with an emphasis on appropriate mitigation measures and on the necessity of adopting the One Health approach during the COVID-19 pandemic.  相似文献   

2.
This study was aimed at monitoring the effect of melatonin implants on selected hematological and biochemical indices as well as on morphology changes of lungs, liver, spleen, kidneys and brain in minks. Experiments were carried out on 300 minks aged 2 years, bred under conditions of a large-herd farm and fed identical feedstuff. Melatonin implants were inserted subcutaneously to the minks in the form of granules containing 6 mg of melatonin. The control group consisted of minks from the basic herd. A better appetite and higher body weights characterized the experimental minks. Skins obtained were larger, thinner and covered with springy hair with a good sheen, yet were stragglier than in the control group. The hematological indices analyzed did not differ between the groups and were within referential values. Biochemical indices of liver and kidneys profiles were better in the experimental group. In the experimental minks, histopathological examinations demonstrated lesser intensity of disorders in brain and liver circulation, lesser intensity of degenerative lesions in liver tissues and kidneys as well as smaller infiltration of lymphocytic and plasmatic cells in lungs and liver.  相似文献   

3.
为评价水貂阿留申病灭活疫苗的免疫效果 ,对接种疫苗水貂及阿留申病阴性、阳性水貂的死亡、空怀、流产、产仔、产仔成活数进行了比较 ,结果证实 ,水貂阿留申病灭活疫苗对水貂具有较好的免疫保护作用。  相似文献   

4.
水貂犬瘟热流行病学调查   总被引:1,自引:0,他引:1  
为了调查山东省水貂犬瘟热的流行病学情况,对2010年8月-2012年8月期间由诸城、文登等地养貂场送诊的996份水貂病例进行了临床诊断和病原学检查。结果显示,共检出犬瘟热病毒阳性病料223份,阳性率为22.39%。其中,犬瘟热病毒与其他病原混合感染136例,占阳性病例的60.99%;阳性样本中未免疫病例116个;诸城检出阳性病例数最多,为147例;3月龄水貂发病率最高,占阳性病例的43.0%;水貂感染犬瘟热病毒主要症状为眼、鼻黏液性分泌物增多、脚垫增厚、呼吸困难;主要病理变化为肠、脑部出血。结果表明,犬瘟热依然是危害水貂养殖的重要疫病,且犬瘟热病毒易与其他病原混合感染;免疫接种能有效预防水貂犬瘟热,且宜在3月龄以前进行。  相似文献   

5.
This study investigated digestibilities of nutrients and feed efficiency in female mink at the different dietary protein levels during the mink growth period. Effects of dietary protein on growth performance of minks were also measured. Sixty 45‐day‐old healthy female minks were randomly assigned to 6 treatment groups with 10 animals in each group. Animals were fed diets varying in protein levels: 28% (Group I), 30% (Group II), 32% (Group III), 34% (Group IV), 36% (Group V) and 38% (Group VI), respectively. The digestibilities of key nutrients were determined on Day 14 after initiating the experiment and the last 3 days. From the beginning of the study, body weight and feed intake were weighed and recorded every other week in order to calculate the average daily bodyweight gain and the feed efficiency. The trial had demonstrated that nitrogen intake was greatly significantly different, which was affected by dietary protein levels (p < 0.001). Growth performance of minks was impaired when dietary protein level was at 28%. When dietary protein level was at 34%, minks had the best daily gains, feed efficiency, and digestibilities of some key nutrients.  相似文献   

6.
Self-biting behavior (SBB) is a serious behavioral disorder in farmed minks, but little is known about the biological basis of this disorder. The present study examined for the first time the hepatic and cerebral oxidative stress biomarker levels in SBB minks and compared them with those in normal ones to study the association of oxidative stress and SBB in minks. Calcium-activated adenosine triphosphatase (Ca2+ATPase) activities were also determined to investigate whether the Ca2+ pump in brain is affected. Twenty male SBB minks and 20 male normal minks were chosen in December. The brain and liver of each mink were harvested immediately after slaughter to test oxidative stress biomarkers. All parameters were determined by using a spectrophotometer. Our findings were as follows: SBB minks produced more malondialdehyde with 51% increase in brain (P < 0.01) and 22% increase in liver (P < 0.01) compared with normal minks. Similarly, the hepatic and cerebral protein carbonyls in SBB minks were 18.5% (P < 0.01) and 30% higher (P < 0.001), respectively. Glutathione peroxidase activities in brain and catalase activities in both tissues of SBB minks were markedly lower than those of normal group (P < 0.01). However, SBB minks had higher total superoxide dismutase (SOD), Cu/Zn-SOD, and Mn-SOD activities in both tissues (P < 0.05 or P < 0.01). Significant depletion of glutathione and vitamin E levels were observed in SBB minks (P < 0.01 or P <0 .05). Calcium-activated adenosine triphosphatase activities in the brain of SBB minks were inhibited (P < 0.01). Our results supported the oxidative stress hypothesis in minks with SBB.  相似文献   

7.
本文旨在探讨饲粮蛋白质水平对育成期母貂生长性能、营养物质消化代谢及血清中与氮代谢相关的生化指标的影响。选择健康(50±3)日龄断奶的雌性水貂 60只,平均体重为(0.577±0.073)kg,随机分成 6组,每组 10个重复,每个重复 1只,单笼饲养。6组水貂分别饲喂蛋白质水平为 28%、30%、32%、34%、36%、38%的试验饲粮。在水貂 65、80、95、110日龄时各进行 1次消化代谢试验,分析各日龄水貂的蛋白质消化率、脂肪消化率、氮沉积、蛋白质生物学价值、饲料转化率及体增重等指标。结果表明:50~65日龄,38%蛋白质组体增重极显著高于28%和 32%蛋白质组(P<0.01),38%蛋白质组饲料转化率极显著优于 28%和 32%蛋白质组(P<0.01);50~110日龄,32%和 34%蛋白质组体增重显著高于 28%蛋白质组(P<0.05)。95日龄时,32%、34%和 38%蛋白质组的蛋白质消化率极显著高于 28%和 30%蛋白质组(P<0.01)。110日龄时,34%蛋白质组蛋白质生物学价值和净蛋白质利用率极显著低于其他试验组(P<0.01)。110日龄时,38%蛋白质组尿素氮含量极显著高于其他各组(P<0.01);34%和36%蛋白质组总氨基酸含量显著高于 28%蛋白质组(P<0.05)。综合试验中的测定指标,建议50~65日龄,水貂饲粮蛋白质水平为 36% ~38%;66~80日龄,水貂饲粮蛋白质水平为 34% ~36%;81~110日龄,水貂饲粮蛋白质水平为 32% ~34%。  相似文献   

8.
Blood samples from 100 minks from a research farm using bacteriologically high quality feed and from 55 minks from another farm supplying bacteriologically inferior feed, as well as from nine minks from Denmark from two farms providing still better quality feed than both Finnish farms – all minks apparently clinically healthy – were analyzed for some haematological and chemical data: total leucocyte count, haemoglobin, ornithine carba-moyltransferase (OCT), alkaline phosphatase (AP), alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), γ-glutamyl-transferase (Γ-GT), total bilirubin and creatinine. The Finnish minks supplied with high quality feed had more optimal values of total leucocytes, haemoglobin, OCT, AP and creatinine than minks receiving feed with higher bacterial contamination. The Danish minks had better blood values in the investigated parameters except for lower haemoglobin and total bilirubin, which showed no significant difference.  相似文献   

9.
The effect of different dietary protein levels and DL‐methionine (Met) supplementation on hair growth and the resulting pelt quality in mink was studied. Four groups of male mink were fed with four isocaloric diets containing 32% (P32), 24% (P24), 16% (P16) or P24+Met (0.8%) crude protein of dry matter (DM) from September to December. Skin biopsies were taken at the pelting. Histological techniques and computer‐assisted light microscopy were used to determine the ratio of activity (ROA) of under hairs and guard hairs respectively. The results showed that when the dietary protein level reduced from 32% to 16%, body length, number and diameter of under hairs and guard hairs of minks declined, and pelt length and pelt weight of minks decreased significantly (p < 0.05). These parameters were similar between P32 and P24 with Met supplementation (p > 0.05). The hair follicle density of the winter coat was not influenced by the dietary protein levels and Met supplementation (p > 0.05). Low‐protein diets content led to a reduction of hair follicle developing to next phase. It was documented that 24% crude protein of DM with Met supplementation during growing‐furring period was sufficient for minks to express their genetic capacity to develop hair follicles and achieve the prime fur characteristics. Overall this study demonstrated that hair growth and hair properties in pelts are very dependent on the dietary protein and Met supply in the growing‐furring period of minks.  相似文献   

10.
本试验旨在研究饲粮粗蛋白质(CP)和粗脂肪(EE)水平对冬毛期雄性水貂生长性能、营养物质消化率及氮代谢的影响,以明确冬毛期水貂饲粮CP和EE的适宜水平。试验采用2×3因子试验设计,即2个CP水平(32%和36%)和3个EE水平(10%、20%和30%),共配制6种试验饲粮。选取84只(120±5)日龄健康雄性水貂,随机分成6组,每组14个重复,每个重复1只。预试期7 d,正试期85 d。结果表明:32%CP组水貂平均日增重(ADG)、蛋白质消化率、脂肪消化率、碳水化合物消化率及氮代谢各指标均显著或极显著低于36%CP组(P0.05或P0.01)。30%EE组水貂末重、ADG和氮沉积含量显著或极显著高于10%EE组(P0.05或P0.01);30%EE组水貂平均日采食量、料重比、干物质消化率、蛋白质消化率、碳水化合物消化率、食入氮含量和粪氮排出量显著或极显著低于10%EE组(P0.05或P0.01)。饲粮CP和EE水平对水貂脂肪消化率有显著交互作用(P0.05)。综合以上指标,在本试验条件下,饲粮CP水平为36%、EE水平为20%或30%时,冬毛期水貂可获得较佳的生长性能,且能够提高水貂对蛋白质的利用率。  相似文献   

11.
水貂生理生化血液流变学常值的研究   总被引:1,自引:0,他引:1  
水貂系哺乳纲,鼠类科,为珍贵的毛皮兽。该场所养的水貂系60年代从挪威,丹麦,1982年英国,1991年美国加拿大引进水貂后代。1990 ̄1992年对礤血液流变学,生理生化常值进行了测试,并选择健康的水貂测试数据进行了处理。经国际联机检索,尚未发现有关水貂的血液流变学的任何报道材料。  相似文献   

12.
本试验旨在研究不同组合益生菌对育成期水貂生长性能和营养物质消化率及氮平衡的影响。选择96只60日龄、健康状况良好的水貂,随机分为4组,每组24只,公、母各半。对照组饲喂基础日粮,试验1、2、3组分别在基础日粮中添加0.06 g地衣芽孢杆菌+0.06 g枯草芽孢杆菌、6 g安琪酵母+12 mL乳酸菌、0.06 g地衣芽孢杆菌+0.06 g枯草芽孢杆菌+6 g安琪酵母+12 mL乳酸菌。在水貂育成期内进行饲养与消化代谢试验,分析不同组合益生菌对水貂平均日采食量、平均日增重、料重比、粗蛋白质和粗脂肪的消化率及沉积氮、蛋白质生物学价值和净蛋白质利用率的影响。结果表明,与对照组相比,试验1组公貂的干物质消化率和试验2组公貂的脂肪消化率显著下降(P<0.05),但不同组水貂的生长性能和氮平衡及母貂的营养物质消化率未受到益生菌的影响(P>0.05)。提示,日粮中添加益生菌不会显著改善育成期水貂的生长性能、营养物质消化率及氮平衡,故在水貂健康的前提下,无需在育成貂日粮中添加益生菌。  相似文献   

13.
The keeping of minks in farms is widely disputed. As the present article illustrates, improvement in the management of farm minks can be achieved with relatively little effort. By implementing connecting openings between regular cages the area for living can easily be enlarged, moreover the structure of the cages will be improved. This resides in minks living in groups intensifying their social contacts. Analyses by "Het Spelderholt", Praktijkonderzoek Pluimverhouderij, Beekbergen, Netherlands show that behavioural problems can be significantly reduced by raising minks in adequate groups. Also the interior design and structure of cages is of equivalent importance reducing the occurrence of behavioural problems. The importance of an access to a water basin however has still to be investigated. One striking aspect on the subject of hygiene that has to be pointed out is the regular removal of faeces.  相似文献   

14.
观察绿脓杆菌的G+B+C三个血清型制备的灭活疫苗大规模接种后的速发接种反应及保护性效果观察.用绿脓杆菌G+B+C三个血清型制备的疫苗以小鼠和水貂为实验室观察组,同时设定阴性对照,观察疫苗免疫后的速发接种反应;在养殖场,选择常年因绿脓杆菌引起的水貂出血性肺炎的养殖户,采用预防免疫和发病期紧急预防接种两种方式,并回访保护效果.在实验室对水貂和小鼠皮下接种疫苗,接种后7~21 d观察接种部位和解剖小鼠检查病理学变化,没有出现任何异常反应.从2012年和2013年共制备的5个批次14万头份的疫苗,在对临床推广应用的回访中,只有一个养殖户少量水貂出现接种部位化脓,经查是由于注射部位的肌肉吸收性降低而引起,对预防接种的10万头份中,接种后没有发生绿脓杆菌引起的出血性肺炎,在对4万头份的由于绿脓杆菌引起出血性肺炎的紧急接种中,在5~10 d达到控制本病的目的.结论:G+B+C三个血清型绿脓杆菌疫苗速发接种反应发生率低,预后良好,无论是预防接种还是发病后紧急接种,均具有较好的保护性.  相似文献   

15.
本试验旨在通过研究饲粮中半胱胺对育成期水貂生长性能、营养物质消化率及氮代谢的影响,确定饲粮中半胱胺的适宜添加水平和添加方式。试验采用双因子试验设计,选取56只(86±5)日龄、体重相近的健康雌性短毛黑水貂,随机分为7个组,每组8个重复,每个重复1只。Ⅰ组(对照组)饲喂基础饲粮;Ⅱ、Ⅲ、Ⅳ组分别在基础饲粮中添加60、90、120 mg/kg半胱胺,添加方式为连续添加;Ⅴ、Ⅵ、Ⅶ组分别在基础饲粮中添加60、90、120 mg/kg半胱胺,添加方式为间隔添加(连续添加1周,间隔1周)。预试期7 d,正试期53 d。结果表明:1)饲粮中添加半胱胺极显著影响水貂的平均日采食量和料重比(P0.01),对平均日增重无显著影响(P0.05)。Ⅴ组料重比极显著低于Ⅰ、Ⅱ、Ⅳ组(P0.01);平均日增重以Ⅴ组最高,间隔添加组高于连续添加组。2)饲粮中添加半胱胺显著影响水貂的粗蛋白质消化率和粗脂肪消化率(P0.05),极显著影响干物质消化率(P0.01),且均以Ⅴ组最高。半胱胺添加方式极显著影响水貂的干物质消化率(P0.01),间隔添加组极显著高于连续添加组(P0.01)。3)饲粮中添加半胱胺显著或极显著影响水貂的氮代谢指标(P0.05或P0.01)。Ⅴ、Ⅵ、Ⅶ组氮沉积显著高于Ⅰ组(P0.05),Ⅴ、Ⅵ、Ⅶ组净蛋白质利用率和蛋白质生物学价值均极显著高于Ⅰ组(P0.01),且以Ⅴ组最高。半胱胺添加方式极显著影响水貂的食入氮含量、尿氮排出量、净蛋白质利用率和蛋白质生物学价值(P0.01)。间隔添加组水貂的食入氮含量和尿氮排出量极显著低于连续添加组(P0.01);间隔添加组的氮沉积显著低于连续添加组(P0.05);间隔添加组的净蛋白质利用率和蛋白质生物学价值极显著高于连续添加组(P0.01)。半胱胺添加水平显著影响水貂的粪氮排出量(P0.05),90 mg/kg组水貂的粪氮排出量显著低于60 mg/kg组(P0.05)。综合各项指标,育成期水貂饲粮中半胱胺的适宜添加水平为60 mg/kg,适宜添加方式为间隔添加。  相似文献   

16.
腹泻水貂检出携带耶尔森菌HPI毒力岛的大肠杆菌   总被引:3,自引:0,他引:3  
为了解大肠杆菌引起水貂腹泻的机理,进行了小肠结肠炎耶尔森菌HPI毒力岛基因的检测,并对其菌株做毒力试验。用PCR扩增法检测毒力岛基因irp2和fyua,小鼠腹腔注射检测菌株毒力。结果:从3个貂场腹泻病死水貂脏器以及粪便中分离出血清型分别为078、029和038的大肠杆菌,对3个血清型大肠杆菌进行毒力岛检测,均检出携带小肠结肠炎耶尔森菌HPI毒力岛基因irp2和fyua。3个血清型078、029和038的大肠杆菌均使小鼠发病死亡。结果表明水貂腹泻是由携带小肠结肠炎耶尔森茵HPI毒力岛基因irp2和fyua的大肠杆菌引起,该茵对水貂的健康具有潜在的威胁。  相似文献   

17.
为研究水貂的繁殖率,避免母貂空怀,2010年3月3~20日对大连名威貂业有限公司配种期种貂精液进行了检查,结果表明:2 933只种公貂中有103只无精或死精,占种公貂总数的3.51%。说明做好精液检查是提高水貂妊娠率和产仔率的关键。如果采用同一只公貂复配,可降低母貂空怀率17.55%,能有效提高水貂的繁殖率。  相似文献   

18.
随着生物技术的发展,人们对有益微生物的应用越来越重视,应用范围也越来越广泛。为了减少肠道疾病的发生,提高水貂抗病能力、生产性能和综合效益,我们试验应用复合有益微生物茵饲喂水貂,获得了良好的技术成效和经济效益。  相似文献   

19.
本试验旨在研究不同蛋白质和脂肪水平颗粒料对冬毛期水貂生长性能、营养物质消化率、氮代谢和毛皮品质的影响。选择(135±5)日龄的健康雄性水貂72只,随机分成6组,每组12只。采用双因子试验设计,分别按34%粗蛋白质、18%粗脂肪(Ⅰ组),34%粗蛋白质、16%粗脂肪(Ⅱ组),32%粗蛋白质、18%粗脂肪(Ⅲ组),32%粗蛋白质、16%粗脂肪(Ⅳ组),30%粗蛋白质、18%粗脂肪(Ⅴ组),30%粗蛋白质、16%粗脂肪(Ⅵ组)配制6种试验饲粮,并制成颗粒料。预试期7 d,正试期60 d。结果表明:Ⅰ组和Ⅲ组水貂的平均日增重(ADG)极显著高于Ⅱ组、Ⅳ组和Ⅵ组(P0.01);18%脂肪组水貂的末重显著高于16%脂肪组(P0.05),18%脂肪组水貂的ADG极显著高于16%脂肪组(P0.01)。Ⅵ组水貂的蛋白质消化率极显著低于其他各组(P0.01);18%脂肪组水貂的蛋白质消化率极显著高于16%脂肪组(P0.01);34%和32%蛋白质组水貂的蛋白质消化率极显著高于30%蛋白质组(P0.01)。Ⅱ组水貂的氮沉积和蛋白质生物学价值显著高于Ⅳ组(P0.05);Ⅱ组、Ⅲ组和Ⅳ组水貂的净蛋白质利用率显著高于Ⅵ组(P0.05);饲粮脂肪水平对水貂的氮代谢相关指标未产生显著影响(P0.05),饲粮蛋白质水平显著影响了水貂的净蛋白质利用率(P0.05)。34%和32%蛋白质组水貂的活体长显著高于30%蛋白质组(P0.05);34%蛋白质水貂的皮长显著高于30%蛋白质组(P0.05),但饲粮脂肪、蛋白质水平及两者的交互作用对水貂的皮长没有产生显著影响(P0.05)。综合试验结果得出:饲粮脂肪水平影响冬毛期水貂的末重,而饲粮蛋白质水平对冬毛期水貂的活体长具有影响;本试验条件下,冬毛期水貂饲喂脂肪水平为18%和蛋白质水平为32%~34%的颗粒料可获得较好的生长性能和毛皮品质。  相似文献   

20.
为了解水貂皮肤毛囊发育的变化规律,本试验采集0~6周龄初生的美国短毛黑公水貂的背中部皮肤样品,用HE染色法制备组织切片,在显微镜下观察其皮肤毛囊结构及变化规律。结果发现,水貂的皮肤在出生前就已经基本发育完成,初级毛囊、次级毛囊的毛干具有髓质;水貂出生时可见初级毛囊而无次级毛囊,初级毛囊的密度随周龄的增加而增加,于4周龄后降低,初级毛囊在水貂4周龄后不再发育或很少发育, 4周龄时可见次级毛囊,次级毛囊随水貂体表的增长毛密度增加,且在水貂出生后大量发育。水貂6周龄时S/P值为2.95±0.23,次级毛囊仍将大量发育。水貂背中部表皮呈先增厚后变薄的变化,真皮随着周龄的增加而增厚;初级毛囊、次级毛囊随周龄的增加而加深。  相似文献   

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