Serum susceptibility of bovine pasteurellas.

In this study, the serum sensitivity of 23 P. haemolytica isolates and 18 P. multocida isolates was determined by incubating dilutions of bacteria with equal volumes of fresh or heat-inactivated bovine serum for one, two, or three hours. Clinical isolates of both Pasteurella species were resistant to serum, whereas isolates from asymptomatic cattle varied in serum susceptibility. The classical pathway of complement appeared to be the principal means of complement mediated killing as detected by incubation in the presence or absence of EGTA-MgCl2. Lyzozyme and iron saturation of serum did not greatly affect serum susceptibility with either of the Pasteurella species.     

Detection of urease-negative Bordetella bronchiseptica from the field

Four urease-negative Bordetella bronchiseptica isolates originating from pigs were examined by phenotypic and molecular methods. The phenotypic properties of the isolates were in harmony with the data of the literature, except for the lack of urease activity in conventional tube test, API 20 NE and Diatabs? assays. Using genotypic methods, the urease-negative isolates did not differ from the urease-positive reference strain. They were positive in species-specific and ureC PCR, and all strains showed uniform bands in PCR-RFLP studies of flaA genes. The reason for the lack of urease activity, a characteristic considered species specific for B. bronchiseptica, needs to be studied further. The finding underlines the significance of genotyping when the phenotypic identification of B. bronchiseptica seems questionable.     

RHDV在多种属动物体内分布及细胞免疫水平

应用纯化兔出血症病毒(Rabbit hemorrhagic disease virus,RHDV),接种小鼠、豚鼠、SPF鸡、仔猪4d后剖杀,分离组织,通过电镜观察、血凝试验(HA)、RT-PCR,进行体内分布检测;同时将上述动物进行3次免疫,三免后10d分离外周血淋巴细胞进行IFN-γ、IL-4、WST检测病毒刺激指数(SI)。结果显示,通过电镜观察未见到病毒粒子;HA检测结果为肝脏的HA价最高,而肺脏最低;RT-PCR未检测到目的基因;WST检测结果免疫组刺激指数高于对照组;免疫组的IFN-γ和IL-4检测数高对照组。结果表明,RHDV在多种属动物分布规律相同,均能产生细胞免疫反应,为下一步试验奠定基础。     

Distribution of erythromycin following intramuscular administration in laboratory animals]

Levels of erythromycin in the blood and organs of rabbits, rats and mice were determined after the i. m. implantation of the drug Erythromycin inj. ad usum vet. at doses of 10 mg kg-1 live weight (rabbits), and/or 25 mg kg-1 (rats) and 1 mg pro toto--approximately 40 mg kg-1 (mice). A diffusion plate method and the germ Sarcina lutea CCM 552 were used to find out the antibiotic in samples. Sensitivity of the method used was 0.025 microgram ml-1 (g). In rabbits the level of the antibiotic was maintained in the blood and examined organs and tissues (lungs, liver, kidney, muscles and the wall of the small intestine) by the above dose for more than 12 hours--except liver. The values obtained for the organs and tissues were mostly higher than those obtained for the blood. The highest levels were found in the kidneys and lungs. Neither did the dose of 20 mg kg-1 l. w. maintain the significant level of erythromycin in the blood serum in the course of 24 hours. The results obtained in rats and mice almost coincided with the distribution of erythromycin in the rabbit organisms, and the affinity of this antibiotic with the pulmonary tissue was proved.     

Transmissible encephalopathies in animals.

Scrapie in sheep and goats is the best known of the transmissible encephalopathies of animals. The combination of maternal transmission of infection and long incubation periods effectively maintains the infection in flocks. A single sheep gene (Sip) controls both experimental and natural scrapie and the discovery of allelic markers could enable the use of sire selection in the control of the natural disease. Studies of experimental rodent scrapie show that neuroinvasion occurs by spread of infection from visceral lymphoreticular tissues along nerve fibers to mid-thoracic cord. The slowness of scrapie is due to restrictions on replication and cell-to-cell spread of infection affecting neuroinvasion and subsequent neuropathogenesis. Probably both stages in mice are controlled by Sinc gene, the murine equivalent of Sip. The glycoprotein PrP may be the normal product of Sinc gene. Posttranslationally modified PrP forms the disease specific "scrapie associated fibrils" and may also be a constituent of the infectious agent. Scrapie-like diseases have been reported in mink and several species of ruminants including cattle. All of them may be caused by the recycling of scrapie infected sheep material in animal feed. The human health implications are discussed.     

Distribution of Rhodococcus equi in animals,birds and from the environment

Extract

Madam:— As well as causing sporadic infections in animals, Rhodococcus (Corynebacterium) equi has been isolated from the gastro-intestinal tract of healthy grazing animals and from the environment. ^{(1 )(5)(6)(8)(11)} R. equi has been isolated in this laboratory from cattle and pigs in association with tuberculosis- like lesions and from lungs and abscesses from horses and deer.     

质粒介导的喹诺酮耐药基因在动物源金黄色葡萄球菌的流行分布

为了解广东省动物源金黄色葡萄球菌耐药现状、分析耐喹诺酮类金黄色葡萄球菌耐药分子特征,本研究从2010—2011年广东33个养殖场的不同动物来源的样本中分离鉴定出46株金黄色葡萄球菌,采用二倍琼脂稀释法测定对14种抗菌药物的敏感性;采用聚合酶链式反应(PCR)检测耐喹诺酮金黄色葡萄球菌grlA、grlB、gyrA、gyrB基因在喹诺酮耐药决定区(QRDR)的突变特征、质粒介导喹诺酮类耐药(PMQR)基因(qnr、aac6′-Ib-cr、oqxA和qepA)的流行分布特征,同时还检测了β-内酰胺酶编码基因(blaCTX-M、blaCMY和blaSHV)、质粒介导金黄色葡萄球菌耐氟苯尼考的基因(cfr和fexA)和万古霉素耐药基因(vanA、vanB和vanC)。结果表明,46株金黄色葡萄球菌对克林霉素耐药率最高为67%,对环丙沙星和氟苯尼考耐药率为52%,对青霉素、氨苄西林、庆大霉素、红霉素、四环素和复方新诺明的耐药率在40%⁵0%之间,对苯唑西林和氯霉素耐药率为28%,对妥布霉素耐药率为13%,对头孢噻肟的耐药率在10%左右,有2株耐万古霉素。20株耐环丙沙星金黄色葡萄球菌的grlA和gyrA基因的QRDR发生了碱基突变并导致编码的氨基酸发生改变,GrlA氨基酸只有1种突变模式,Ser80→Phe,而GyrA氨基酸存在3种突变模式:Ser84→Leu,Ala或Phe。PMQR基因中,oqxA检出率最高(80%),其次是aac6′-Ib-cr占13%,qnrS1检出3株、qnrD检出2株。检测到2株菌株携带超广谱β-内酰胺酶编码基因blaSHV-12;23株氟苯尼考耐药菌株全部携带fexA基因,其中3株同时携带cfr基因;2株耐万古霉素菌株未检测到相关耐药基因。广东省动物源金黄色葡萄球菌多重耐药现象较为普遍,本研究首次在动物源金黄色葡萄球菌中检测到超广谱质粒编码的喹诺酮耐药基因流行分布广泛,大多数菌株同时携带2种以上质粒编码的耐药基因,提示养殖过程或治疗过程中使用任何一种药物(尤其是动物促生长剂)都可以筛选出耐药菌株。     

Hypervitaminosis D in fur-bearing animals.

Investigations concerning the effect on fur-bearing animals of large doses of vitamin D3 were carried out. The material comprised 62 animals in all--10 silver foxes, 17 blue foxes and 35 mink (Table II). Daily doses of 5 IU vitamin D3/g body weight for two months did not produce clinical symptoms in the foxes. However, a short while after the dose was increased to 10 IU, the animals showed loss of appetite, had difficulty in moving, were apathetic and developed dark coloured faeces. Analysis of blood serum showed markedly raised calcium values (Table III). Calcium deposits were demonstrated in the kidneys and in some cases also in the musculature, gastric mucosa, bronchi and the larger blood vessels. No abnormal signs were shown by 30 mink which received 0.6--0.7 IU vitamin D3/g body weight for five months. PM findings were normal.     

Comparative pathology of glomerulonephritis in animals.

Glomerulonephritis constitutes an important category of renal diseases in animals and has been recognized with increasing frequency in the last decade. We report here the comparative morphologic aspects of glomerulonephritis as a naturally occurring disease of animals. We briefly review the immunopathogenesis of glomerulonephritis. The morphology of renal lesions occurring in glomerulonephritis in dogs, cats, cattle, sheep, horses and swine has been reviewed with emphasis on the range and specificity of various glomerular lesions and on the comparison of lesions between various species. A distinction was made between glomerulonephritis as a primary disease entity and glomerulonephritis associated with other disease processes. Primary idiopathic glomerulonephritis occurred in all species but was most commonly recognized as a clinically important disease in dogs and cats. Glomerulonephritis also occurred in association with other diseases such as equine infectious anemia, chronic hog cholera, canine pyometra, dirofilariasis, feline leukemia virus infection and canine systemic lupus erythematosus.     

Management of fractures in small animals.

Fracture repair in small animals has arrived at a crossroads because of advances in fracture repair and client demands. Research into bone healing and repair techniques, collective professional experience,economics, and client demands are obligating veterinarians to greater expertise in the actual act of repairing fractures. The influx of surgery specialists into burgeoning private practices has improved access to specialty service beyond what the limited number of academic practices could previously provide and has raised the local standard of practice for orthopedic surgery at the same time. The necessity to deal with the preoperative and postoperative management of traumatized small animals by the general practitioner has not changed, however.Treatment of the small animal patient with a fractured bone does involve accurate definition of the fracture, selection of an appropriate method of fracture fixation from the variety of devices available, and correct application of the fixation. Far more than these, however, it involves assessment and treatment of the traumatized patient as a whole,including preanesthetic evaluation of critical body systems, preoperative preparation of the patient and client, and postoperative management of the repaired fracture and patient.