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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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British and British x Continental steers (n = 560; initial BW = 339.4 +/- 1.76 kg) were used in a serial slaughter study with a completely random design to evaluate effects of zilpaterol hydrochloride (ZH; 8.33 mg/kg of dietary DM basis) on performance and carcass characteristics. Treatments were arranged in a 4 x 4 factorial (112 pens; 7 pens/treatment; 5 steers/pen) and included duration of ZH feeding (0, 20, 30, or 40 d before slaughter plus a 3-d ZH withdrawal period) and days on feed (DOF) before slaughter (136, 157, 177, and 198 d). No duration of ZH feeding x slaughter group interactions were detected for the performance measurements (P > 0.10). Final BW did not differ (P = 0.15) between the 0-d group and the average of the 3 ZH groups, but ADG was greater for the average of the 3 ZH groups during the period in which ZH diets were fed (P < 0.01) and for the overall feeding period (P = 0.05). As duration of ZH feeding increased, DMI decreased (P = 0.01) and G:F increased linearly (P < 0.01). With the exception of KPH (P = 0.022), no duration of ZH feeding x slaughter group interactions (P > 0.10) were detected for carcass characteristics. Regardless of the duration of ZH feeding, cattle fed ZH had greater HCW (P < 0.01), greater dressing percent (P < 0.01), less 12th-rib fat (P < 0.01), larger LM area (P < 0.01), less KPH (P = 0.03), and lower yield grade (P < 0.01) than the 0-d cattle. The 0-d group had greater marbling scores (P < 0.01) than cattle fed ZH diets, with a tendency for a linear decrease in marbling score (P = 0.10) as duration of ZH feeding was extended. A greater percentage of carcasses in the 0-d group graded USDA Choice or greater (P < 0.01) than in the 3 ZH groups, whereas the percentage of Select carcasses was greater (P = 0.01) for the 3 ZH groups. From d 0 to end (P = 0.04) and during the last 43 d on feed (P < 0.01), ADG responded quadratically to DOF before slaughter. No differences were detected among slaughter groups for DMI for the entire trial period; however, a quadratic response (P = 0.02) was observed for the final 43 d before slaughter. A quadratic response was also detected for the final 43 d before slaughter (P < 0.01) and from d 0 to end (P = 0.02) for G:F. Final BW, HCW, dressing percent, and 12th-rib fat increased linearly (P < 0.01) as DOF before slaughter increased. Our results indicate that no substantial effects on performance and carcass measurements were observed when ZH was fed for 30 or 40 d as opposed to 20 d, and that effects of ZH generally did not interact with DOF before slaughter.  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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The field experiments were conducted for two crop years of 1997?–?98 and 1998?–?99 at the Indian Agricultural Research Institute, New Delhi to study the effect of wheat, legume and legume enriched wheat residue (WR) on soil fertility under the rice-wheat cropping system. A rice-wheat cropping system without incorporation of residue depleted organic C over initial level by 0.061%, kjeldahl-N by 0.012%, available P by 0.7?kg ha???1 and available K by 36?kg ha???1, whereas incorporation of Sesbania green manure (SGM), mungbean residue (MBR), SGM?+?WR and MBR?+?WR increased organic C over the initial level by 0.071, 0.100, 0.163 and 0.133%, respectively, kjeldahl-N by 0.001, 0.004, 0.001 and 0.005% respectively, available P by 2.7, 5.0, 8.5 and 3.2?kg ha???1, respectively and available K by 35, 5, 92 and 12?kg ha???1, respectively in 2 years. As compared with no residue control, incorporation of WR increased organic C by 0.036?–?0.102%, kjeldahl-N by 0.002?–?0.007% and available K by 23?–?45?kg ha?1, whereas incorporation of SGM and MBR increased organic C by 0.082?–?0.132 and 0.103?–?0.161%, respectively, kjeldahl-N by 0.009?–?0.023 and 0.005?–?0.013%, respectively and available K by 5?–?71 and 4?–?45?kg ha???1, respectively. Incorporation of WR with SGM and MBR was more effective and increased organic C by 0.121?–?0.224 and 0.125?–?0.194%, respectively, kjeldahl-N by 0.005?–?0.029 and 0.010?–?0.021%, respectively and available K content by 23?–?128 and 11?–?116?kg ha???1. Nitrogen application to rice also increased organic C, kjeldahl-N, available P and available K content in soil and also increased effects of crop residues. Crop residues had no significant effect on available P content in soil. Incorporation of WR with SGM and MBR with adequate fertilizer-N is, thus, recommended for building up organic C, kjeldahl-N and available K content in soil.  相似文献   
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This study evaluates the effects of ascorbic acid and its interaction with follicle-stimulating hormone (FSH) on the morphology, activation, and in vitro growth of caprine preantral follicles. Ovarian fragments were cultured for 1, 7, or 14 d in minimum essential medium (MEM) containing ascorbic acid (50 or 100 μg/mL), FSH (50 ng/mL), or both of these substances. Ovarian tissue that was either fresh (control) or cultured for 1, 7, or 14 d was processed for histological and ultrastructural evaluation. The results showed that after 14 d of culture, medium supplemented with 50 μg/mL of ascorbic acid alone or combined with FSH showed higher rates of follicular survival compared with MEM. After 7 d of culture, FSH, ascorbic acid at 50 μg/mL with or without FSH, and ascorbic acid at 100 μg/mL increased the percentage of follicular activation compared to fresh control. In addition, FSH alone significantly increased the percentage of growing follicles after 14 d. The combination of 50 μg/mL of ascorbic acid and FSH promoted a significant increase in oocyte and follicular diameter after 7 d of culture. Ultrastructural and fluorescent analysis confirmed the integrity of follicles cultured with 50 μg/mL of ascorbic acid and FSH after 14 d. In conclusion, the combination of 50 μg/mL of ascorbic acid and FSH maintained follicular integrity and promoted follicular activation and growth after long-term in vitro culture of caprine preantral follicles.  相似文献   
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The 1994 eruption of Rabaul, in Papua New Guinea, involved a small plinian eruption at Vulcan and a vulcanian eruption on the opposite side of the caldera at Tavurvur. Vulcan's ash leachates indicate seawater interaction that is consistent with earlier observations of low sulfur dioxide emissions and the presence of ice crystals in the initial plinian eruption cloud. In contrast, Tavurvur ash leachates indicate no seawater interaction, and later sulfur dioxide emissions remained high despite low-level eruptive activity. Silicic melt inclusions indicate that the andesitic melt contained about 2 weight percent water and negligible carbon dioxide. Mafic melt inclusions in Tavurvur ash have water and carbon dioxide contents that vary systematically over the course of the eruption. The mafic melt inclusions suggest that a mafic dike intruded from below the silicic chamber and provide further evidence that mafic intrusions drive caldera unrest.  相似文献   
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