Observations on blood-borne parasites of domestic livestock in the Lower Juba Region of Somalia

The commonest parasite to be found in blood of cattle in the Lower Juba Region is Theileria mutans. Antibodies against Trypanosoma spp. and Anaplasma marginale could be detected serologically whereas no antibodies against T. parva and T. annulata were present. A list of ticks collected between 1980 and 1982 in the above mentioned area shows that vectors of T. mutans are common. As the cattle throughout the region are indigenous Somali Boran it seems that endemic stability is maintained and mortality from T. mutans infection is negligible. It is not yet clear whether pathogenic strains of T. mutans similar to those isolated in East Africa occur.     

宁夏地区牛场E种肠道病毒的分离与鉴定

牛肠道病毒感染是近年来国内新报道的一种传染病,其病原体为微RNA病毒科肠道病毒属中的肠道病毒。本研究应用双抗体夹心ELISA方法对宁夏地区的部分牛群肠道病毒感染进行了调查,其感染率为9.85%、27%、28.2%。应用Vero细胞从采自宁夏牛群的粪便样品中分离出2株病毒,采用病毒学技术、过氧化物酶单层细胞试验和分子生物学技术对分离毒鉴定发现,2株病毒均为肠道病毒。应用PCR技术扩增分离毒的部分核苷酸序列,并对其进行比对分析发现,分离的2株病毒均为E种肠道病毒。该结果将为宁夏地区肠道病毒感染的防控提供依据。     

Interference between drug-resistant and drug-sensitive stocks of Trypanosoma congolense in goats

A study was undertaken in goats to investigate the ability of two unrelated stocks of Trypanosoma congolense, one of which is highly sensitive to isometamidium chloride and one which is drug-resistant, to become established in the presence of an existing infection with the other stock. The goats, which were initially infected with the sensitive strain and were then challenged with the resistant strain, were cured by treatment at 0.1 mg kg-1 isometamidium, indicating that the resistant stock did not establish an infection. Goats initially infected with the resistant stock, which were then challenged with the sensitive stock, experienced temporary remission of infection followed by relapse after treatment at 0.1 mg kg-1 isometamidium. In contrast, the goat infected only with the resistant stock remained parasitaemic following treatment at 0.1 mg kg-1. This suggests that superinfection with the sensitive stock resulted in the establishment of infection, which suppressed the resistant stock to below the limit of detection of the method used. These observations suggest that isometamidium-resistant stocks may be less viable than sensitive strains, and could explain the relative scarcity of isometamidium resistant in the field.     

Isolation of Mycoplasma capricolum-like strains from chickens

Members of the genus Mycoplasma infect a wide range of hosts, but individual Mycoplasma species tend to exhibit a considerable degree of host specificity. We characterized Mycoplasma strain 700, isolated from a kidney of a layer hen in Spain and Mycoplasma strains ULB-A and ULB-B, isolated from the air sac and from the bile of stunted broiler chickens in Slovenia. The serologic examination showed that these three strains are antigenically unrelated to all of the recognized Mycoplasma species of avian origin, but closely related to the ruminant mycoplasma Mycoplasma capricolum subspecies capricolum (M. capricolum). The comparison of their 16S rRNA gene sequences with the sequence of M. capricolum (California kid) revealed 99.66% sequence identity for the strain 700 and 99.59% identity for strains ULB-A and ULB-B. Moreover, the predicted DnaK sequences of the M. capricolum-like strains, isolated from chickens, were identical to DnaK sequences of M. capricolum. Comparison of their dnaK gene sequences with M. capricolum showed 99.64% sequence identity for strain 700 and 99.27% identity for strains ULB-A and ULB-B. In the flock from which M. capricolum-like strains ULB-A and ULB-B were isolated, the majority of chickens (83% of the chickens examined) raised antibodies reacting with M. capricolum antigens. Notably, the infection of chickens with M. capricolum-like strains represents an unusual exception to the range of Mycoplasma species host specificity.     

Isolation of enterotoxigenic strains of staphylococci from dogs

The ability of 309 staphylococcal isolates from household dogs to produce enterotoxin, coagulase, thermonuclease and hemolysin was investigated. A total of 52 (16.8%) isolates from 45 out of 150 dogs examined were enterotoxigenic when tested for enterotoxin types A, B and C. Based on sites sampled, 33 (20.5%) out of 161 isolates from the anterior nares were enterotoxigenic while from dorsal skins 19 (12.8%) out of 148 isolates were enterotoxigenic. Staphylococcal enterotoxin C(SEC) was predominantly produced as 21 (6.8%) isolates elaborated it and also accounted for 40.4% of all enterotoxins produced by isolates. Staphylococcal enterotoxins A(SEA) and B(SEB) were produced by 10 (3.2%) and 16 (5.2%) strains, respectively. Mixed enterotoxin types AB, AC and BC were produced by 1,3 and 1 strains, respectively. With human plasma, 17.1% of coagulase-positive and 15.0% of coagulase-negative strains were enterotoxigenic. However, using canine plasma, 19.1% and 6.9% of the coagulase-positive and negative isolates, respectively, were enterotoxigenic. The incidence of enterotoxigenicity was 16.9% amongst thermonuclease-positive isolates and 16.3% for thermonuclease-negative strains.Alpha hemolysin was predominantly produced by 180 (60.2%) isolates and 19.9% of these were enterotoxigenic. Beta hemolysin was produced by 36 (11.7%) isolates with 13.9% enterotoxigenic, while 87 (28.2%) exhibited gamma hemolytic pattern amongst which 11.5% were enterotoxigenic.Based on data provided on coagulation of human and canine plasmas and hemolytic patterns, it is concluded that a large proportion of canine isolates from this environment are not of canine biotypes, but are most probably human biotypes.     

Therapeutic activity of isometamidium chloride in Boran cattle against a tsetse-transmitted clone ofTrypanosoma congolense with a low level of drug resistance

Summary Experiments were conducted with a clone ofTrypanosoma congolense, IL 3580, which exhibited a low level of resistance to isometanidium chloride. Five cattle were treated intramuscularly with isometamidium chloride at a dose rate of 0·5mgkg⁻¹ body weight (BW) and challenged 28 days later with 5Glossina morsitans centralis infected withT. congolense IL 3580. All 5 cattle and 15 untreated steers challenged on the same day became parasitaemic by day 15 post-infection. Thus, at a dose of 0·5 mg kg⁻¹ BW, the prophylactic action of isometamidium chloride did not extend to 28 days following treatment. Subsequently, the 20 steers were divided into 4 groups of 5 animals each and treated with isometamidium chloride at one of the following dose rates; 0·5 or 1·0 mg kg⁻¹ BW intramuscularly and 0·5 or 1·0 mg kg⁻¹ BW intravenously (Groups A, B, C and D, respectively). Group A consisted of the 5 animals that had previously been treated with isometamidium chloride. Animals relapsed in all groups except those in Group B, treated intramuscularly with isometamidium chloride at a dose of 1·0 mg kg⁻¹ BW. Four of the 5 animals in Group A, treated intramuscularly with isometamidium chloride at a dose of 0·5 mg kg⁻¹ BW relapsed following a mean interval of 16 days post-treatment. Similarly, infections in all animals in Groups C and D, given intravenous injections of isometamidium chloride at a dose of 0·5 and 1·0mg kg⁻¹ BW, respectively, were not eliminated as a result of treatment. The mean intervals to first detection of parasitaemia in these 2 groups following treatment were 14 and 20 days, respectively. The results therefore indicate that intravenous administration of isometamidium chloride does not enhance the drug’s therapeutic efficacy in the treatment of aT. congolense clone which expresses a low, but significant, level of resistance to isometamidium.

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Resumen Se condujeron experimentos con un clon deTrypanosoma congolense IL 3580, que exhibió un bajo nivel de resistencia al cloruro de isometamido. Clinco animales fueron tratados vía intramuscular con cloruro de isometamidio a una dosis de 0·5mg kg⁻¹ de peso vivo (PV). Posteriormente fueron enfrentados 28 días después con 5Glossina morsitans centralis infectadas conT. congolense IL 3580. Todos los infectados (n=5) y 15 novillos sin tratar infectados el mismo día, presentaron parasitèmia el día 15 pos-infección. Se desprende entonces, que la dosis de 0·5 mg kg⁻¹ de PV de cloruro de isometamidio, no protegió más allá de 28 días. Subsecuentemente, los 20 novillos fueron divididos en 4 grupos de 5 animales cada uno, siendo tratados con cloruro de isometamidio, con una de las siguientes dosis: 0·5 ó 1·0 mg kg⁻¹ de PV intramuscular y 0·5 ó 1·0 mg kg⁻¹ vía intravenosa (Grupos A, B, C y D, respectivamente). El Grupo A consistió de 5 animales que habían sido tratados previamente con cloruro de isometamidio. Todos los animales recayeron, excepto aquellos del Grupo B, que habían sido tratados vía intramuscular, a una dosis de 1·0 mg kg⁻¹ de PV. Cuatro de los 5 animales en Grupo A, tratados intramuscularmente con 0·5 mg kg⁻¹ deisometamidio, recayeron 16 días promedio después del tratamiento. Similarmente, las infecciones en todos los animales de los grupos C y D, tratados vía intravenosa con dosis de 0·5 y 1·0 mg kg⁻¹ de PV, respectivamente, no fueron eliminados como resultado del tratamiento. El promedio de intervalos para la detección de parasitémia en estos dos grupos después del tratamiento, fueron 14 y 20 días, respectivamente. Los resultados indican, que la administración de cloruro de isometamidio intravenoso, no aumenta la eficacia terapéutica de la droga en el tratamiento del clon deT. congolense, el cual expresa un bajo pero significativo nivel de resistencia al isometamidio.

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Résumé Des expériences ont été conduites avec un clone deTrypanosoma congolense IL 3580, qui a montré un faible niveau de résistance au chlorure d’isométamidium. Cinq bovins ont été traités par voie intramusculaire avec ce médicament à la dose de 0,5mg/kg⁻¹ de poids vif (PV) Ils ont été soumis 28 jours plus tard au contact de 5Glossina morsitans centralis infectées par Trypanosoma congolense IL 3580. Les cinq animaux en totalité, ainsi que 15 taurillons non traités soumis le même contact se sont révélés parasités au 15e jour de l’infection. Ainsi, à la dose de 0,5 mg Kg⁻¹ PV, l’action prophylactique de chlorure d’isométamidium n’a pas duré jusqu’au 28 e jour suivant le traitement. En conséquence, les 20 taurillons ont été divisés en 4 groupes de 5 animaux chacun et traités au chlorure d’isométamidium avec l’une des doses suivantes: 0,5 ou 1,0 mg/kg⁻¹/PV, par voie intramusculaire et 0,5 ou 1,0 mg/kg⁻¹/PV par voie intraveineuse, constituant ainsi les groupes A, B, C et D respectivement. Le groupe A comprenait les 5 animaux précocement traités. Tous les animaux ont fait une rechute, excepté ceux du groupe B traités par voie intramusculaire avec le chlorure d’isométamidium à la dose de 1,0 mg/kg⁻¹/PV. 4 des 5 animaux du groupe A, traités par la même voie mais à la dose de 0,5 mg kg⁻¹/PV ont rechuté après un intervalle moyen de 16 jours suivant le traitement. De même chez tous les animaux des groupes C et D ayant respectivement re?u une injection intraveineuse aux doses de 0,5 et 1,0 mg/kg⁻¹/PV, le traitement n’a pas éliminé l’infection. Les intervalles moyens pour la première détection de la parasitémie dans ces deux groupes ont été respectivement de 14 à 20 jours. De ces résultats, on peut déduire que l’injection intraveineuse du chlorure d’isométamidium n’accro?t pas l’efficacité thérapeutique du produit dans le traitement d’une trypanosomose due à un clone deTrypanosoma congolense qui exprime à un degré faible, mais significatif, sa résistance à ce médicament.

     

猫源弓形虫虫株的分离与鉴定

将猫的心、脑、舌用盐酸-胃蛋白酶溶液消化处理后接种小白鼠，经连续传代分离弓形虫虫株，用特异PCR方法对所分离的虫株进行了鉴定。分别从24只猫的样品中分离出8株弓形虫虫株，用弓形虫种特异的PCR方法对8个虫株进行鉴定。均得到弓形虫的特异条带；测序证明所扩增出的DNA片段确为弓形虫的核糖体DNA第一 内转录间隔区（ITS1）部分序列。研究结果表明，将动物组织用盐酸-胃蛋白酶溶液消化处理后接种小白鼠是一种分离弓形虫虫株较为理想的方法．特异PCR方法能准确、快速地鉴定弓形虫虫株。     

南疆地区小花棘豆中苦马豆素的分离与鉴定

摘要：小花棘豆(Oxytropis glabra)草粉经稀盐酸浸提、过滤、滤液上732强酸性阳离子交换树脂,用1 mol/L 氨水洗脱,得到总生物碱。将总生物碱用甲醇完全溶解、过滤,回收甲醇后的残留物,过180 μm硅胶柱,用氯仿∶甲醇∶氨水∶水（体积比为70∶26∶2∶2）混合溶剂洗脱,薄层层析检测,合并同类项,挥干后将残留物在90 ℃、-0.094 MPa条件下升华,得到白色针状结晶。经薄层色谱、熔点、紫外光谱、红外光谱、质谱、核磁共振分析,确定为苦马豆素,提取率为19.95 mg/kg。     

3株猪源绿色气球菌的分离鉴定

为确定云南省不同地区3个猪场仔猪发生非创伤性四肢运动障碍的病原因素,无菌采集病死仔猪深部组织样品,采用血琼脂分离培养病原菌,随后对分离菌株做形态观察、生化试验、药敏试验及16 S rRNA基因测序分析.结果:从3个猪场病料中均分离到菌落及个体形态一致的细菌,其16 S rRNA基因序列与NCBI中7株绿色气球菌参考菌株...     

Isolation of benzimidazole resistant strains of Ostertagia circumcincta from British sheep

Two strains of Ostertagia circumcincta were isolated from sheep in Great Britain; one (CVL strain) from a breeding flock maintained at the Central Veterinary Laboratory, the other (H2 strain) from a commercial flock in southern England. Their resistance to benzimidazole anthelmintics was assessed by means of in vitro egg hatch assays and slaughter trials. In vitro egg hatch assays gave calculated ED50 estimates of 0.799 micrograms thiabendazole/ml for the CVL strain and 0.794 micrograms thiabendazole/ml for the H2 strain, compared with ED50 estimates of 0.038 micrograms thiabendazole/m and 0.036 micrograms thiabendazole/ml for two known susceptible strains of O circumcincta. There was a 40.7, 28.4 and 66.9 per cent reduction in the group mean worm burdens of lambs infected with the CVL strain following treatment with thiabendazole, fenbendazole and oxfendazole, respectively, and 23.8, 0.0, 79.6, 52.7, 99.9 and 100 per cent reduction in the group mean worm burdens of lambs infected with the H2 strain following treatment with thiabendazole, fenbendazole, oxfendazole, albendazole, levamisole and ivermectin, respectively. Detailed field histories for both strains are given.     

Antimicrobial susceptibilities of Campylobacter strains isolated from broilers in the southern part of Japan from 1995 to 1999

Cecal contents (16 samples/each flock) of broilers derived from 212 flocks were investigated for colonization of Campylobacter from 1995 to 1999 in the southern part of Japan, and the isolates were tested for antimicrobial susceptibilities. C. jejuni-positive flocks numbered 42 (19.8%) and C. coli-positive ones 26 (12.3%); Campylobacter spp. were recovered from 68 flocks (32.1%) in total. MICs of ampicillin, erythromycin (EM), tetracycline, nalidixic acid (NA), norfloxacin (NFLX), and ofloxacin (OFLX) to these 68 Campylobacter isolates were determined. Quinolone-resistant Campylobacter isolates numbered 22 (32.4%). All the isolates except one were cross-resistant to NA, OFLX, and NFLX. A high frequency of quinolone-resistance was found in both C. jejuni and C. coli, whereas a high level of EM-resistance was found in only C. coli strains. All C. jejuni isolates were sensitive to EM.     

“禽出败”病原的分离鉴定及疫苗株的筛选

禽出败即禽霍乱(fowl cholera,FC),又称禽巴氏杆菌病、禽出血性败血症,是由多杀性巴氏杆菌(Pasteurella multocida)引起的家禽和野禽的急性败血性传染病。通常呈急性败血性经过和剧烈下痢,死亡率高。近年来在清新县的高田、清城区的东城、源潭、石角等地养鸡场陆续发生禽出败,用药治疗可以控制鸡的死亡,停药2～3 d后鸡     

Isolation of pathogenic strains of Haemophilus somnus from the female bovine reproductive tract.

The prevalence of Haemophilus somnus in the genital tract of slaughtered and live cows in southern Ontario was investigated. The vagina and uterus of slaughtered cows were swabbed separately. Live cows were examined and sampled in two field surveys: Centre A and Centre B. In the former, aspirated mucus secretions and in the latter, specimens obtained by guarded swabbing were examined bacteriologically. Haemophilus somnus was isolated from 28 genital tracts of 461 slaughtered (6.1%), and seven of 199 live (3.5%) cows during the centre B survey. The isolates were recovered from both normal and diseased reproductive tracts. Fourteen strains isolated from genital organs were examined for pathogenicity in vivo to test the occurrence of pathogenic isolates. In the initial stage of the in vivo study on pathogenicity, each of the fourteen isolates was examined on one calf using an intracisternal inoculation. Subsequently, one pathogenic and one nonpathogenic strain were inoculated into five calves each to statistically confirm their pathogenic potential. Of 14 genital isolates of H. somnus examined in an intracisternal calf assay, six (43%) caused a fatal peracute neurological disease, while eight were nonpathogenic. A comparative pathological study of pathogenic and nonpathogenic isolates showed that the former caused a severe fatal suppurative meningoencephalitis whereas the latter caused no lesions whatsoever or a mild leukocytic leptomeningitis. The salient data obtained in this study indicate that there are pathogenic strains of H. somnus in the genital tract of apparently normal cows as well as of those with inflammatory disease.     

Isolation of toxigenic strains of Pasteurella multocida from lungs of pneumonic swine

Lungs from 113 pneumonic pigs were examined for Pasteurella multocida. The lungs were smeared directly onto blood agar and homogenized in brain-heart infusion broth and then inoculated intraperitoneally in mice. Pasteurella multocida isolates were typed for serotypes A (by hyaluronidase inhibition of capsule) and D (by acriflavine autoagglutination). Strains were tested for toxin production by intradermal injection of 0.2 ml of filtered 24-hour culture supernatants into guinea pigs. Most lungs (70.8%) yielded isolations. Most isolants (87.5%) were type A and 12.5% were type D. Of the type D strains, 80% were toxigenic. Of the type A isolants, 18.2% were toxigenic.     

利用MLST技术探讨不同地区致病性耐药鸡源大肠杆菌的遗传进化关系

选取来自山东等10省698株鸡源大肠杆菌为研究对象,分别利用PCR、微量肉汤稀释法、MLST技术方法进行系统进化群分群、耐药表型检测、分子分型,并采用Bio Numerics v4.0软件和SPSS20.0软件进行数据处理分析。结果显示,低致病群B_1群为48.85%(341/698)和非致病群A群24.64%(172/698)分布较多,高致病群D群20.20%(141/698)和B_2群为6.31%(44/698)。鸡源大肠杆菌耐药严重,12种药物的耐药率约在50%以上。B_2和D群菌株对8种抗菌药的耐药率高于A和B_1群菌株,其中对庆大霉素、大观霉素、头孢噻呋、氨苄西林和奥格门丁5种药物极显著性差异(P<0.01),对氟苯尼考和复方新诺明显著性差异(P<0.05)。135株高致病菌株经MLST分型得到48个ST型,ST117(12株)和ST354(12株)最多,其次是ST115(8株),ST2309(8株),ST10型(7株),ST69(6株),ST1011(5株),ST1158(5株)。有29个ST型各1株,18株菌株未分出序列型。不同地区大肠杆菌ST型分布存在差异,ST69和ST354型分布最为广泛(4个省),其次是ST115、ST117和ST2309型(3个省),ST10、ST48、ST57、ST362、ST371、ST1011和ST1158(2个省),其余36个ST型菌株仅在1个省市有检出。135株菌株分为35个聚类簇,其中23个聚类簇的遗传相似性在40%以下,但有6个聚类簇菌株间的遗传相似性均在80%以上。48个ST型菌株共获得了76种耐药谱。我国各地健康鸡群隐性携带相对较高比例的高致病菌株,且耐药程度相对严重,耐药谱较广。鸡源大肠杆菌菌株分布具有多态性和地域性,ST型与耐药谱之间无相关性。