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1.
Tuberculosis in wild seals and characterisation of the seal bacillus   总被引:3,自引:0,他引:3  
SUMMARY Tuberculosis was diagnosed in 3 otariid seals found dead on beaches at 3 locations on the south coast of Western Australian between May 1990 and March 1991. This confirms that tuberculosis is present in the 2 native seals (Neophoca cinerea and Arctocephalus forsteri) in Western Australian waters. Mycobacterium sp isolated from the lungs of 2 of the seals were studied to determine the similarity of the strains to each other, to the strains isolated during 1986 from Australian sea lions and New Zealand fur seals kept in captivity at a marine park near Perth, Western Australia, and to a strain isolated in 1988 from a seal trainer who worked with the infected captive seals for 3 years. After restriction endonuclease analysis (REA) with the endonucleases Bst Ell, Bcl I and Pvu II, one of the wild seal strains appeared to have identical DNA fragment patterns to the strains from the captive seals and the seal trainer. The other wild seal isolate had identical REA profiles using Bst EII and Bcl I, but a minor difference was detected using Pvu II. Differences in these isolates were more clearly seen in restriction fragment length polymorphisms after hybridisation with two DNA probes. The secretory protein MPB70, present in M bovis, was not detected in wild seal isolates using sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting techniques. Analysis of protein and DNA fragment profiles indicated that seal tuberculosis isolates form a unique cluster within the M tuberculosis complex.  相似文献   
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Mean selenium and vitamin E (alpha-tocopherol) concentrations in the liver, myocardium and skeletal muscle of nine goat kids with nutritional myodegeneration (NMD) were significantly lower than those in a group of nine kids dying from other causes. Each of the 18 kids was from a different property in the southern half of the North Island. The polyunsaturated fatty acid composition of the liver, myocardium and skeletal muscle was not significantly different between the two groups, but the overall level of peroxidisable polyunsaturated fatty acids appeared high in both groups. A further 21 kids with confirmed NMD and live 'controls', submitted as routine cases to Palmerston North Animal Health Laboratory, were included with the above 18 kids in a comparison of liver selenium and alpha-tocopherol concentrations. Kids with NMD had liver selenium concentrations ranging from 170-1100 (mean = 380) nmol/kg and alpha-tocopherol from 0.7-11.0 (mean =2.2) micromol/kg. In control kids, the liver selenium concentration ranged from 530-4300 (mean = 1220) nmol/kg and a-tocopherol from 1.7-14.0 (mean = 5.6) pmollkg. Although these ranges overlapped, the results suggest that liver selenium concentrations <500 nmol/kg and alpha-tocopherol concentrations <2.5 micromol/kg should be regarded as deficient. Liver selenium concentrations from 500-1100 nmol/kg and alpha-tocopherol concentrations from 2.5-10 micromol/kg should be considered marginal. Goat kids appear to require more selenium than lambs or calves which may explain the higher prevalence of NMD in kids. In some cases, however, the disease is associated with low alpha-tocopherol suggesting that supplementation with selenium alone may not always be sufficient.  相似文献   
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BACKGROUND: An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg?1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry  相似文献   
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Advisory committee urges changes at OSI   总被引:1,自引:0,他引:1  
A Gibbons 《Science (New York, N.Y.)》1991,254(5036):1287-1288
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Diagnosis of pneumonia caused by Rhodococcus equi can be made more rapidly by use of a polymerase chain reaction (PCR) assay than by use of conventional bacteriologic culture techniques. Use of a PCR assay aids in the differentiation between virulent and avirulent strains of R equi, and the assay may be used to identify R equi in feces and soil of breeding farms.  相似文献   
9.
Summary A study of the several interspecific and inter-subspecific crosses indicated that albinism in groundnut is recessive and in these crosses is controlled by triplicate recessive loci.ICRISAT Paper No. JA-336  相似文献   
10.
Biotech pipeline: bottleneck ahead   总被引:2,自引:0,他引:2  
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