D型肉毒毒素灭高原鼠兔试验

0.1%、0.15%和0.2%浓度的D型肉毒毒素毒饵对高原鼠兔Ochotona curzoniae的灭洞率分别为:71.4%、76.5%和83%.在5%显著水平上,3个浓度之间灭杀效果差异不显著.试验结果表明,3个浓度的D型肉毒毒素对高原鼠兔的灭杀效果与0.1%的C型肉毒毒素相当.     

玉树市藏霸喇种畜场应用D 型肉毒灭鼠剂大面积鼠害防治效果调查

为提高玉树地区寒牧退化草地植被恢复的治理效果,降低高原鼠兔、高原田鼠对试验区草地补播的破坏。本研究以优质燕麦为基饵,拌制添加D型肉毒灭鼠剂浓度为1.5%的毒饵,投放至试验区内0.133万hm²亩寒牧退化草地,随机划定25×25 m²样方3个,采用堵洞开洞法计算灭鼠区内鼠害防治效果。样方调查结果显示:平均灭洞率均在90%以上,灭鼠效果良好,为后期草地植被恢复奠定了良好基础。     

D型肉毒梭菌毒素杀灭高原鼠兔试验

<正> 肉毒毒素是肉毒梭菌在生长繁殖过程中产生的一种细菌外毒素。根据毒素抗原的不同,将其分为A、B、C、D、E、F、G 7个型。D型肉毒梭菌在我国比较少见,对其应用方面的研究尚未见报告。 为测试D型肉毒梭菌毒素对高原鼠兔的杀灭效果,     

D型肉毒毒素防治高原鼠兔小区试验及示范推广

经小区试验和大面积示范推广结果表明,D型肉毒毒素水剂作为一种新型生物灭鼠制剂,不仅对高原鼠兔有较好的防治效果,而且不伤害鼠类天敌,对人、畜安全,同时减少了化学药品对草地的污染,因此,在草地鼠害治理中,推广应用这一新型生物灭鼠技术,对持续控制草地鼠害,保护草地生态环境,维护草地生物多样性有重要的现实意义.     

D型肉毒毒素防治高原鼠兔小区试验及示范推广

经小区试验和大面积示范推广结果表明,D型肉毒毒素水剂作为一种新型生物灭鼠制剂,不仅对高原鼠兔有较好的防治效果,而且不伤害鼠类天敌,对人、畜安全,同时减少了化学药品对草地的污染,因此,在草地鼠害治理中,推广应用这一新型生物灭鼠技术,对持续控制草地鼠害,保护草地生态环境,维护草地生物多样性有重要的现实意义。     

C型肉毒梭菌毒素杀灭高原鼠兔试验

<正> 有史以来,鼠类就与人类为敌。鼠类给人类带来的巨大灾难,绝不亚于其他自然灾旱,鼠患危害之烈,已受到全世界的普遍关注。夏河县草场高原鼠兔(Ochotona curzoniae Hodgson)危害面积达43.3万亩,占整个鼠害总面积的37.98％。由于高原鼠兔啃食牧草嫩茎、叶、花、种子及根茎,抑制了优良牧草的生长发育,减少了草场可利用面积。同时,高原鼠兔频繁活动,挖洞形成大片“黑土滩”,造成草     

C型肉毒梭菌毒素灭鼠剂试验与灭鼠效果的研究

对Ｃ型肉毒梭菌干燥毒素的ＬＤ５０,耐药性,蓄积中毒,致畸,毒饵残效期,保存期及灭效方面进行了实验研究,结果为高原鼠兔ＬＤ５０６．７０μｌ／ｋｇ,ＳＬＤ５０１．６７μｌ／ｋｇ,ＬＤ５０９５％置信限３．４７～１１．７０μｌ／ｋｇ小白鼠ＬＤ５０１７０．７０μｌ／ｋｇ,ＳＬＤ５０４．９１μｌ／ｋｇ,ＬＤ５０９５％置信限１０３．００～２４７．００μｌ／ｋｇ,高原鼠兔摄食系数为１．０７,校正灭洞率８６．２１％     

C型肉毒梭菌灭鼠剂对高原鼠兔的试验研究

对Ｃ型肉毒梭菌干燥毒素在高原鼠兔上的ＬＤ５０、耐药性,蓄积中毒,毒饵残效期和保存期等方面进行试验研究。     

青海省贵南县D型肉毒毒秦防治高原鼠兔小区试验报告

通过应用D型肉毒杀鼠素防治高原鼠兔的小区试验,结果表明：1000万毒价／mL的D型肉毒毒素水剂,按1／1000、1．25／1000、1．5／1000、2／1000的浓度配制毒饵,平均校正灭洞率可分别达到87．26％、86．74％、88．37％和90．03％,差异均不显著。本着经济、安全、高效的宗旨,以1．5／1000的浓度配制毒饵使用较为适宜。     

C、D型貂源铜绿假单胞菌的生物学特性鉴定及免疫效果评价

从辽宁和黑龙江2个水貂养殖场死亡水貂肺中分离出13株铜绿假单胞菌,血清型鉴定分别为C型和D型,命名为PK13-C和H2F-D。为了解其作为疫苗株的免疫效果,测定了其运动能力、绿脓菌素生成能力、生长曲线、毒力、免疫原性及耐药性。结果表明,PK13-C对小鼠和水貂的毒力分别为7.5×106CFU和7×105CFU,泳动能力及群集运动能力较强,抽动能力较弱,生物被膜形成能力中等;H2F-D对小鼠和水貂的毒力分别为2.05×107CFU和2.2×106CFU,泳动能力较弱,但群集运动及抽动能力较强,生物被膜形成能力较弱。二者对本血清型菌株的免疫保护率均为100%,对异种血清型菌株的保护率为80%~90%。2个株菌均可产生绿脓菌素。生长曲线显示2个菌株于4h进入对数生长期,于18h左右进入平稳期。药敏试验结果表明,2个株菌对氯霉素、复方新诺明、氨苄西林/舒巴坦耐药。     

D型魏氏梭菌毒素研究进展

魏氏梭菌病是由魏氏梭菌引起的一种重要的人兽共患传染病。可导致各种动物的肠毒血症或坏死性肠炎,D型魏氏梭菌病包括牛、羔羊、绵羊、山羊以及灰鼠的肠毒血症等。D型魏氏梭菌所产的毒素是引起动物死亡的重要因素之一,本文综述了D型魏氏梭菌毒素的结构、功能以及检测方法的研究进展。     

中国疯草防除与利用研究

中国疯草主要布在西南、西北和华北广大牧区，面积达400多万hm^2。多年来，疯草严重威胁着当地畜牧业的发展，造成重大的经济损失。本文从人工防除与利用，生物控制与灭除，化学控制与灭除和动物免疫预防及化学治疗四个方面就有关疯草防除和利用的技术和方法进行综述。     

Optimization of polymerase chain reaction for detection of Clostridium botulinum type C and D in bovine samples

Botulism is a rare but serious paralytic illness caused by a nerve toxin that is produced by the bacterium Clostridium botulinum. The economic, medical and alimentary consequences can be catastrophic in case of an epizooty. A polymerase chain reaction (PCR)-based assay was developed for the detection of C. botulinum toxigenic strains type C and D in bovine samples. This assay has proved to be less expensive, faster and simpler to use than the mouse bioassay, the current reference method for diagnosis of C. botulinum toxigenic strains. Three pairs of primers were designed, one for global detection of C. botulinum types C and D (primer pair Y), and two strain-specific pairs specifically designed for types C (primer pair VC) and D (primer pair VD). The PCR amplification conditions were optimized and evaluated on 13 bovine and two duck samples that had been previously tested by the mouse bioassay. In order to assess the impact of sample treatment, both DNA extracted from crude samples and three different enrichment broths (TYG, CMM, CMM followed by TYG) were tested. A 100% sensitivity was observed when samples were enriched for 5 days in CMM followed by 1 day in TYG broth. False-negative results were encountered when C. botulinum was screened for in crude samples. These findings indicate that the current PCR is a reliable method for the detection of C. botulinum toxigenic strains type C and D in bovine samples but only after proper enrichment in CMM and TYG broth.     

A型肉毒毒素基因的克隆及序列分析

目的:克隆肉毒梭菌(Clostridium botulinum)A型肉毒毒素(BoNTa)编码基因。方法:提取肉毒梭菌国际标准株(62A)基因组DNA,根据肉毒梭菌BoNTa基因(GenBank登录号M30196)序列设计引物,采用LA-PCR方法,扩增出目的基因片段,与pMD18-T载体连接,通过酶切鉴定、测序分析克隆到的A型肉毒毒素基因序列。结果:该基因片段与Genbank中的BoNTa基因序列(GenBank登录号M30196)一致性为100%,预测氨基酸序列一致性为100%。结论:成功克隆肉毒梭菌的A型肉毒毒素基因序列,为肉毒梭菌的快速检测,以及进一步用基因工程方法生产A型肉毒毒素奠定了基础。     

D型肉毒毒素冻干剂的试验

通过保护剂的选择及冻干试验研制了D型肉毒毒素新剂型-D型肉毒冻干剂。试验确定30%蔗糖+10%明胶作为冻干剂的保护剂;室温(13℃~18℃)的保存期为10个月,37℃的保存期为6个月;水分含量为≤5%。同时制定了D型肉毒毒素冻干剂冻干曲线。     

臭氧对畜禽舍空气消毒效果的观察

观察臭氧消毒机在不同作用时间对兔、鸡、鼠等带动物畜禽舍内空气中自然菌的杀菌效果。以平板沉降法采样空气观察臭氧消毒机开启前及开启后10、20、30、40min后兔舍、鸡舍、鼠舍空气自然菌总数。结果表明:随着臭氧消毒机开机时间(臭氧浓度)的增加对空气细菌的杀灭率明显上升。开机30min后,臭氧浓度达到21.4、18.4和25.6mg/m3,对兔舍、鸡舍、鼠舍空气中自然菌的杀菌率分别为100%、91%和90%。     

Effect of Vitamin D 3 on Cadmium Retention by Laying Hens

The effect of cadmium (Cd) and vitamin D 3 on Cd retention in the organism of laying hens was observed. Hens ( n =48) were divided into eight groups with six animals per group as follows: experimental groups 1, 3 and 5 were administered Cd (0.3, 0.6 and 6.0 mg CdCl 2 kg -1 body weight, respectively) daily in water and groups 2, 4 and 6 were administered the same CdCl 2 concentrations supplemented with vitamin D 3 (100 IU hen -1 ). C1 was a control group without any supplements and C2 a control group supplemented only with vitamin D 3 . Samples of inner organs were analysed by atomic absorption spectrophotometry after 6 months of Cd exposure. A significant elevation in Cd levels, mainly in the liver and kidneys, was found. A significant decrease ( P h 0.01) in Cd levels in the liver was recorded after the addition of 6.0 mg CdCl 2 kg -1 body weight and vitamin D 3 , in comparison with the group without vitamin D 3 (18.76 vs. 10.33 mg kg -1 ). A similar decrease in Cd levels in the kidney ( P h 0.001) at the same supplementation dose of Cd was obtained in comparison with the group without vitamin D 3 (145.32 vs. 60.37 mg kg -1 ). The results confirmed that vitamin D 3 is able to reduce the Cd content in the organism of laying hens. The main effect of vitamin D 3 was demonstrated by decreasing Cd retention in the liver and especially in the kidneys.     

Effect of feed type and essential oil product on equine chewing activity

The ingestive and post-digestion effect of a blend of special essential oil compounds (EO) on eating, chewing and faecal parameters were measured in horses. Ingestive effects appear after no adaptation. Post-digestion effects appear after adaptation. Six Icelandic horses were assigned to two groups in a Latin Square subplot design with EO treatments to four different roughage types and four different concentrates. The horses were fed four different roughage meals and two different concentrate meals on each of the four sampling days. Eating time and saliva were observed during meals. Jaw movements (JM) were recorded using a special chewing halter. Eating time was derived from JM and related to DM intake. The size characteristics of faecal particles were measured by using image analysis. All chewing characteristics measured were significantly affected by roughage (p < 0.001) and concentrate type (p < 0.01). EO had a significant ingestive effect on the frequency of observed saliva during concentrate meals. No significant (p < 0.05) post-digestive or ingestive effect of EO was found for any measured chewing characteristic, which was reflected in the absence of effect on faecal particle dimensions. In conclusion, effect of type of roughage and concentrate was more significant than potential effects of EO.     

C、D型二价产气荚膜梭菌抗毒素血清的制备及保护效果评价

为治疗产气荚膜梭菌感染引起的疾病,研究制备了产气荚膜梭菌多价高效抗毒素血清。试验采用C、D型产气荚膜梭菌标准菌株,制备了高浓度外毒素和灭活疫苗,作为免疫原多次免疫绵羊,通过间接ELISA法监测绵羊抗体水平变化,采用小鼠中和试验检验绵羊抗毒素血清保护效果。结果表明:制备的高效价抗C、D型产气荚膜梭菌毒素血清每0.1 m L血清能中和400个C型毒素对小鼠的MLD和600个D型毒素MLD,有良好的应用前景。