广西某地区猪源大肠杆菌耐药性及部分菌株耐药基因调查

试验旨在探究广西某地区猪源大肠杆菌的耐药性及部分菌株所含耐药基因情况,为预防及治疗动物性大肠杆菌类疾病提供参考。采用麦康凯琼脂培养基及伊红美蓝琼脂培养基初步鉴定、显微镜镜检、分子生物学16S rRNA鉴定、药物敏感性二倍肉汤微量稀释法等方法进行大肠杆菌的分离鉴定,并结合PCR相关技术对部分菌株的三十余种耐药基因进行检测。结果显示,从广西某地区采集的猪源病料中共分离得到65株猪源大肠杆菌,其均为多重耐药大肠杆菌且多集中于六重耐药与七重耐药。按所耐抗菌药物的种类分析发现其对β-内酰胺类、磺胺类、大环内酯类药物具有较高耐药性,耐药率分别98.46%、90.77%及84.62%,进一步分析发现其主要是对头孢噻呋钠、阿莫西林、磺胺间甲氧嘧啶、阿奇霉素等抗菌药物具有较高耐药性,对美罗培南、阿米卡星、黏杆菌素较为敏感。对部分菌株所含耐药基因进行整理发现,其多含有四环素类（tetA、tetM）、β-内酰胺类（CTX-m-u）及磺胺类（Sul2）耐药基因。综上所述发现广西地区猪源大肠杆菌耐药性情况较为严重,所含耐药基因也相对较多,因此在实际生产中需采用联合用药等相关措施进行疾病治疗以达到快速高效治疗疾病的目的。     

不同动物源大肠杆菌的耐药性调查

为了解畜禽源大肠杆菌的耐药状况,2011—2012年从患病和健康食品动物中分离鉴定大肠杆菌935株,包括健康猪源606株、患病猪源114株、患病鸡源51株、患病水禽源(鸭和鹅)164株。试验采用琼脂稀释法测定了不同动物来源的大肠杆菌对15种抗菌药物的敏感性。结果发现,大肠杆菌耐药严重,对大部分药物的耐药率超过70.0%,其中氨苄西林、复方新诺明和四环素的耐药率均达到了80.0%以上;仅对头孢西丁、黏菌素和阿米卡星较敏感,但患病水禽源大肠杆菌对阿米卡星的耐药率达到了52.4%,明显高于其他动物。健康畜禽源大肠杆菌对多数抗菌药的耐药率低于患病畜禽源大肠杆菌,表明抗菌药物的使用增加了病原菌对第3代头孢类药物和氟喹诺酮类药物的耐药率,势必增加临床治疗难度。     

肉鸡养殖场沙门菌与大肠杆菌耐药性的周期监测与研究

对定点肉鸡饲养场的沙门菌和大肠杆菌进行监测试验,连续跟踪3个养殖周期,对不同养殖阶段的肉鸡及环境中细菌的耐药性进行测定。结果表明,该养殖场分离到的大肠杆菌对青霉素类的耐药率尤其突出,氨苄西林为88.7%,美洛西林为83.0%。而耐药率低于10%的均为第3代头孢菌素类(头孢唑啉、头孢他啶和头孢曲松)。结果提示该养殖场的大肠杆菌中产超广谱β-内酰胺酶(ESBLs)的菌株不多,142株大肠杆菌筛查的结果,仅有4株产ESBLs。分离到的沙门菌的耐药率总体低于大肠杆菌,尤其对青霉素类和四环素的耐药率明显低于大肠杆菌。但耐药率在10%以下的同样仅有头孢菌素类。     

内蒙古中东部地区不同来源大肠杆菌耐药性调查

本研究旨在调查内蒙古赤峰、通辽地区不同来源的大肠杆菌对抗生素类药物的耐药情况。采用K-B法分析来源于鹅、牛和猪等患病动物分离出的46株大肠杆菌对13种常用的抗生素类药物的耐药性;鹅源和猪源大肠杆菌对盐酸多西环素的耐药率最高,分别达95.2%和93.3%;牛源大肠杆菌对盐酸沙拉沙星、恩诺沙星和盐酸多西环素的耐药率最高,达80.0%。多重耐药性结果表明,患病动物的大肠杆菌以6耐（23.9%）为主;牛源大肠杆菌则以7耐（40%）最多。总体耐药谱型以恩诺沙星/氟苯尼考/盐酸多西环素/阿莫西林/硫酸新霉素为主（24.4%）。不同来源的大肠杆菌对抗生素类药物均产生了严重的耐药性,因此不但要求养殖人员学会合理使用抗生素类药物,同时研究开发逆转耐药性的新药物或对抗生素类药物有增敏效用的新药物十分必要。     

鸭大肠杆菌ESBLs的检测及耐药性分析

本文对临床分离的12株鸭大肠杆菌进行了ESBLs检测,并用K-B纸片法测定了其对常见几种抗菌药物的敏感性,以期为抗菌药的临床合理应用提供依据.结果表明:临床分离的12株大肠杆菌中有4株产ESBLs,检出率为33%.产酶菌对β-内酰胺类抗生素阿莫西林、头孢噻呋的耐药率都高达100%,而不产酶菌对β-内酰胺类抗生素阿莫西林、头孢噻呋的耐药率均为87.5%;4株产酶菌中对氨苄西林、氨曲南耐药率分别为75%、50%,而8株不产酶菌对其耐药率分别为62.5%、0.0%,可见产酶菌的耐药率明显大于不产酶菌.同样,对于氨基糖苷类、喹诺酮类等其他抗菌药物也出现此种情况,说明产酶菌对这些药物存在多重耐药性.所以,临床中应注意通过药敏试验合理选用药物.才能取得好的治疗效果.     

大肠杆菌转座子及整合子携带类型与其多重耐药谱型相关性的研究

为探究猪源大肠杆菌转座子及整合子携带类型与其多重耐药相关性，试验采集贵州省12个规模化养猪场猪肛门拭子，分离鉴定到259株大肠杆菌。采用微量肉汤稀释法测定分离菌株对7类（16种）抗菌药物的最小抑菌浓度（MIC）值，并用PCR方法检测转座子及整合子的携带情况。结果发现，受试菌株对7类（16种）抗菌药物呈现出不同程度的耐药，对大观霉素、庆大霉素、四环素为高度耐药，MIC₉₀的耐药倍数为32倍；对亚胺培南、多黏菌素B表现敏感，MIC₉₀的耐药倍数为2倍，其他药物的耐药倍数介于二者之间。受试菌株多重耐药最高达7重，2重以上耐药率达到100%，多重耐药谱型共计14种，以β-内酰胺类+氨基糖苷类+四环素类+酰胺醇类+磺胺类+氟喹诺酮类、β-内酰胺类+氨基糖苷类+四环素类+酰胺醇类+磺胺类+氟喹诺酮类+多肽类为主，占56.97%。受试菌株转座子和整合子检出率较高，转座子及整合子表型共计20种，其中IScp1+IS26+tnpA+tnp513+intI1和IS26+tnpA+tnp513+intI1的组合类型占比最多，分别为48.48%和26.06%。本试验结果表明，插入元件IScp1与β-内酰胺类药物耐药呈显著或极显著相关（P<0.05，P<0.01），插入元件IS26与氨苄西林耐药相关性极显著（P<0.01），与磺胺异唑耐药相关性显著（P<0.05）；整合子intI1与氨苄西林耐药相关性极显著（P<0.01）；intI2与头孢他啶耐药相关性极显著（P<0.01），与头孢噻呋、恩诺沙星、亚胺培南耐药相关性显著（P<0.05）；IScp1+IS26+tnpA+tnp513+intI1组合类型与复方新诺明耐药相关性极显著（P<0.01）；IS26+tnpA+tnp513+intI1组合类型与复方新诺明耐药相关性显著（P<0.05），与头孢噻呋耐药相关性极显著（P<0.01），但与庆大霉素耐药呈负相关关系（P<0.05）。综上，受试菌株对β-内酰胺类、氟喹诺酮类、磺胺类、氨基糖苷类的多重耐药与转座子及整合子携带类型呈显著或极显著相关。     

鸭大肠杆菌超广谱β-内酰胺酶的检测及药物敏感性分析

分析鸭大肠杆菌的耐药性与超广谱β-内酰胺酶的关系,为临床相关感染的治疗提供理论依据。采用CLSI推荐的初步筛选试验和表型确证试验方法,检测了临床分离的12株鸭大肠杆菌产超广谱β-内酰胺酶的情况,用微量稀释法测定了环丙沙星等9种抗菌药对其的抗菌活性。临床分离的12株鸭大肠杆菌中,有4株产超广谱β-内酰胺酶,检出率为33%。产超广谱β-内酰胺酶的菌株对多种药物耐药,对氟喹诺酮类药物之间产生交叉耐药,对氟喹诺酮类、氨基糖苷类、头孢菌素类产生多重耐药性,产酶菌的耐药性明显大于非产酶菌。产超广谱β-内酰胺酶是鸭大肠杆菌对抗菌药物产生耐药性的主要机制之一。     

山东省某鸭场大肠杆菌病病原的分离鉴定与耐药性分析

致病性大肠杆菌耐药程度日益严重,已对畜牧业生产安全和公共卫生安全构成了较大威胁。2020年山东省某鸭场发生疑似禽大肠杆菌病,大批雏鸭死亡。为精准诊断和了解病原耐药情况,对病死鸭心脏组织病料进行细菌分离,并对分离菌进行16S rDNA鉴定、抗菌药物敏感性测定和β-内酰胺类耐药基因bla_CTX-M检测。结果显示:从2只病死鸭心脏组织中分离出CD4-10、CD4-12等2株大肠杆菌;2株分离菌均对头孢噻肟、头孢噻呋、氨苄西林、环丙沙星、左氧氟沙星、恩诺沙星、链霉素、卡那霉素、强力霉素、萘啶酸和氟苯尼考高度耐药,对多黏菌素、美罗培南和磷霉素敏感,其中CD4-12菌株还对阿米卡星和庆大霉素表现敏感。2株菌均携带bla_CTX-M-1G耐药基因,未携带bla_CTX-M-9G耐药基因。结果表明,该鸭场大批雏鸭死亡是由多重耐药的大肠杆菌感染引起的,且分离菌耐药十分严重,因其携带bla_CTX-M-1G基因而对β-内酰胺类药物耐药。本研究为当地禽大肠杆菌病临床用药、疫苗制备及肉鸭科学养殖提供了信息支持。     

猪源大肠杆菌对氨基糖苷类药物的耐药性以及耐药基因的检测

为指导临床合理用药,根据耐药表型和基因型研究耐氨基糖苷类药物猪源大肠杆菌的流行情况,采用K—B法检测大肠杆菌对氨基糖苷类药物的耐药性,同时用PCR技术扩增氨基糖苷类药物的耐药基因以明确其基因型。结果显示,60株临床分离菌中,耐氨基糖苷类抗生素菌株54株,耐药率为90％;aac（3）-Ⅰ基因PCR扩增均为阴性;aac（3）-Ⅱ基因检出阳性28例,阳性率为46．7％;aac（6’）-Ⅰ基因检出阳性54例,阳性率为90％。结果表明,耐氨基糖苷类药物的大肠杆菌比较普遍,氨基糖苷类耐药基因以aac（3）-Ⅱ和aac（6’）-Ⅰ为主。     

长春地区猪源大肠杆菌的分离鉴定和耐药性分析

为了解吉林省长春地区猪源大肠杆菌的耐药情况,于2013年采集318份猪源样品,分离鉴定大肠杆菌275株。以氨苄西林、头孢噻肟等15种药物进行了药物敏感性实验,多重 PCR 方法进行系统进化分群。结果表明,大肠杆菌分离株对四环素、氨苄西林和磺胺甲基异恶唑耐药最严重（83.63%、52.72%、51.27%）,全部菌株对美洛培南、多粘菌素敏感,其中176 株菌表现为对3类以上抗生素的多重耐药（64.00%）。从仔猪腹泻样品分离大肠杆菌对β-内酰胺类抗生素、喹诺酮类抗生素、四环素、氯霉素及磺胺甲基异恶唑的耐药率显著高于健康猪和猪肉样品分离株的耐药率。大肠杆菌分离株主要为 A 群和 B1群。研究获得了吉林长春地区猪源大肠杆菌耐药性的基本流行病学数据,为指导养殖业的临床用药及耐药性监测提供了依据。     

Prevalence of intestinal parasites in shelter and hunting dogs in Catalonia,Northeastern Spain

To compare the prevalence of intestinal parasites in shelter and hunting dogs in Catalonia, Northeastern Spain, fresh faecal samples from 81 shelter dogs and 88 hunting dogs were collected and analysed by faecal flotation. The overall prevalence of intestinal parasites was 71.6% in each population. In the shelter dog group, 67.9% of dogs were positive for intestinal protozoa and 9.8% were positive for helminths. In the hunting dog group, 20.4% of dogs were positive for intestinal protozoa and 63.6% were positive for helminths. A subset of Giardia-positive samples was evaluated by PCR; Giardia assemblages C or D were detected. These results suggest that comprehensive parasite control measures should be implemented in both shelter and hunting dogs in Catalonia.     

以去盲肠鸡测定发酵血粉和蒸煮血粉的氨基酸利用率

本研究以去盲肠鸡和改良的“ＴＭＥ”法测定了发酵血粉和蒸煮血粉的氨基酸利用率。结果表明，除蛋氨酸外，鸡对发酵血粉的氨基酸利用率显著高于蒸煮血粉（Ｐ＜０．０５）。发酵血粉是一种值得开发利用和推广的蛋白质饲料。     

Comparison of four diagnostic tests for the identification of serum antibodies in small ruminants infected with Mycoplasma agalactiae

AIM: To determine the diagnostic capability of a newly developed Western blot (WB) assay for the detection of serum antibodies against Mycoplasma agalactiae compared with conventional serological tests, and to identify the best test for routine diagnostic use. METHODS: The serological test methods used were: two commercial indirect enzyme-linked immunosorbent assays (ELISA), viz ELISA-1, using a bacterial antigen preparation, and ELISA-2, using a recombinant protein (lipoprotein p48) antigen; the complement fixation test (CFT); and a newly developed WB assay, the latter both using a bacterial antigen preparation. Thirty sera from goats infected with M. agalactiae and 97 sera from non-infected sheep were tested using all four methods. RESULTS: Staining patterns in the WB were quite variable. An immuno-dominant band of 41 kDa was detected in 63% of sera from infected animals. The same band also appeared, although mostly very weakly, in 10% of sera from non-infected animals. When suspicious or very weak reactors were omitted, the diagnostic sensitivity (DSE) and diagnostic specificity (DSP), respectively, for the four assays were: WB=56.7%, 97.9%; ELISA-1=76.7%, 99.0%; ELISA-2=56.7%, 100%; and CFT=40.0%, 94.8%. CONCLUSIONS: ELISA-1 performed best in this comparison. While the WB can be used, it did not have a technical advantage over the ELISA. The CFT should be discouraged as the primary screening method for contagious agalactia and should be replaced by ELISA-1. Results from this study confirm that serological test methods for contagious agalactia are useful for the detection of infected flocks but will not detect every individual infected animal.     

猫尾草属牧草苗期耐盐性评价

对16份引自俄罗斯的野生猫尾草属(Phleum pratense)材料,在0.3%,0.4%和0.5%NaCl胁迫下,通过株高、存活率、叶片伤害率的测定,采用隶属函数法和标准差系数赋予权重法进行耐盐性综合评价。结果表明:供试16份猫尾草属牧草在0.3%,0.4%和0.5%NaCl胁迫下存活率分别为30%~83%,13%~67%和7%~57%。根据耐盐性综合评价值(D)得出猫尾草耐盐性顺序,ZXY03P-465>ZXY03P-168>ZXY03P-149>ZXY03P-389>ZXY03P-117>ZXY03P-81>ZXY03P-240>ZXY03P-370>ZXY03P-290>ZXY03P-64>ZXY03P-17>ZXY03P-340>ZXY03P-135>ZXY03P-186>ZXY03P-419>ZXY03P-33。     

Cross-bred Cattle Protected against Hyalomma anatolicum anatolicum by Larval Antigens Purified by Immunoaffinity Chromatography

Antigens from larvae of Hyalomma anatolicum anatolicum were extracted and purified by immunoaffinity chromatography using immunoglobulin ligands from cross-bred animals immunized with soluble larval antigen. Affinity-purified antigen (Aff-TLE) and a total larval extract (TLE) were used to immunize cross-bred (Bos indicus×Bos taurus) cattle. The group immunized with Aff-TLE rejected 71.6% of larvae and 77.3% of nymphs. However, the rejection percentages were lower in the TLE-immunized group. No significant changes in the feeding period, moulting percentages or moulting period of engorged larvae and nymphs were recorded. There was, however, a significant decrease in the number of resultant nymphs p<0.01) and adults (p<0.01) in the ticks fed on the Aff-TLE-immunized group. The Aff-TLE antigen was 93.3% purified. SDS-PAGE analysis identified a 39 kDa protein, reported for the first time, as the antigen responsible for the induction of resistance in the host.     

民和县草地鼠害防治项目调查及效益分析

通过连续5年实施草地鼠害防治项目,共防治高原鼢鼠5.67×104hm2,防效达92.82%,牧草产量增加525kg/hm2;防治高原鼠兔2.66×104hm2,防效达98.43%,牧草产量增加450～525kg/hm2。生态、经济、社会效益显著。     

Persistent efficacy of moxidectin canine sustained-release injectable against experimental infections of Ancylostoma caninum and Uncinaria stenocephala in dogs

The efficacy of moxidectin canine sustained-release injectable administered at fixed intervals before administration of an oral hookworm challenge was evaluated in 40 laboratory dogs. Groups of eight dogs were treated with the moxidectin sustained-release formulation by SC injection approximately 3, 4, 5, or 6 months before being given oral inoculations with 300 Ancylostoma caninum larvae on Day 0 and 400 Uncinaria stenocephala larvae one day later. Dogs were euthanized 21 days after parasite inoculations. Fecal samples and the intestinal contents collected at necropsy from each dog were examined for hookworms. Fecal egg count reductions based on geometric means relative to controls were 99.2% (3 months) to 81.2% (6 months). The reduction in A. caninum worm recoveries at 3, 4, 5, and 6 months based on geometric means were 94.7%, 90.3%, 82.0%, and 60.2%, respectively. The mean reductions in U. stenocephala worm counts at these intervals were 94.6%, 85.3%, 71.6%, and 48.2%,respectively.     

多花木蓝种子硬实与萌发特性研究

通过不同方法对多花木蓝种子进行处理,测定了吸水率、发芽率、发芽指数和活力指数。结果表明,不同处理对提高多花木蓝发芽率的效果差异达极显著水平(P<0.01)。采用98%浓硫酸浸种时间分别为1、2、3、4、5、6、7、8、9、10 min处理中,以6 min处理效果最好,发芽率达95%;采用60℃热水浸种时间分别为5、10、15、20、25、30、35 min处理中,以25 min处理的效果最好,发芽率为71.6%。     

Fertility after artificial insemination using a soybean-based semen extender in sheep

The present study aimed to compare the fertility of ewes intrauterinally inseminated with frozen-thawed semen using a soybean-based semen extender (AndroMed) with those of ewes intrauterinally inseminated with frozen-thawed semen using a Tris-based extender containing either egg yolk or BSA. Suffolk ewes (n=104) were treated with an intravaginal sponge containing 40 mg fluoroprogesterone acetate (FGA) for 12 days and an intramuscular injection of 500 IU equine chorionic gonadotropin to induce estrus and ovulation during the non-breeding season (July, 2007). Intrauterine insemination was carried out 40-46 h after removal of the FGA sponge (n=90), regardless of the incidence of estrus. The pregnancy rates were not significantly different among the semen extenders containing egg yolk (64.5%) or BSA (58.6%) and AndroMed extender (56.7%). The lambing rates (64.5, 55.2 and 56.7% for the semen extenders containing egg yolk, BSA and AndroMed, respectively) and prolificacy (1.59 to 1.75) were also not significantly different. The present results indicate that an egg yolk-containing semen extender can be replaced with the non-animal derived extender AndroMed, which could be used for intrauterine insemination using frozen-thawed ram semen without reducing fertility.     

Cysteine proteinases Fas1 and Fas2 are diagnostic markers for Fasciola hepatica infection in alpacas (Lama pacos)

Circulating antibody against Fasciola hepatica antigens was determined by enzyme-linked immunosorbent assay (ELISA) and immunoelectrophoresis in alpacas naturally exposed to F. hepatica. Serological assay parameters were established by using sera from eight infected animals and seven controls with no record of this parasitic infection. Excretory--secretory (ES-) products, Fas1- and Fas2-ELISA were used to survey 307 alpacas from a F. hepatica endemic area in the Peruvian Andes. Seroprevalence of F. hepatica infection varied from 56.7, 64.8 and 66.8% measured by Fas1-, Fas2- and ES-ELISA, respectively. The sensitivity for ES-ELISA was 95%, corresponding Fas1- and Fas2-ELISA sensitivity values were 90 and 95%. In this population, 7% of animals were positive for F. hepatica eggs in faeces, other parasites detected were Trichuris sp. (40%), Nematodirus sp. (34.6%), Lamanema sp. (12.8%) and Eimeria sp. (11.8%). The results show that F. hepatica infected animals elicit circulating antibodies against ES, Fas1 and Fas2. Fas2-ELISA may be proposed as a sensitive assay for the immunodiagnosis of fasciolosis in alpacas.