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Coated (V-13) and uncoated (V-22) formulations of dichlorvos were used to treat experimentally established Hyostrongylus rubidus infections of pigs at intervals after exposure to infective larvae. Both dichlorvos formulations were efficacious against the adult stomach worm H rubidus, but showed little or no activity against 5- or 15-day-old worms. Neither formulation was as effective against H rubidus in sows as in barrows and gilts. 相似文献
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The re-emergence of indigenous forest in an urban environment, Christchurch, New Zealand 总被引:4,自引:0,他引:4
Glenn H. Stewart Maria E. Ignatieva Colin D. Meurk Richard D. Earl 《Urban Forestry & Urban Greening》2004,2(3):149-158
Christchurch, the second largest city in New Zealand is a planned city on a coastal plain on the east coast of the South Island. The birth of the city and the subsequent century of development was characterised by colonial values and tree and garden planting with familiar European species along with those from Australia, North America, and eventually all other continents. The image of an “English garden city” with classical parks of oaks and willow-lined rivers became the accepted norm and the way in which the city has been promoted to potential tourists. Gardening is one of the top two recreational activities and exotic species greatly outnumber native species in the flora and in gardens. This has had serious consequences for the highly fragmented and degraded indigenous vegetation and its co-adapted wildlife. A few hardy indigenous species continued to regenerate through this period, but since the 1970s, there has been a progressive change of attitude and interest in reclaiming the natural heritage of the city, manifest in widespread private and public planting of indigenous species and active habitat restoration. In this article we examine the indigenous and exotic shrub and tree components of the Christchurch flora as planted street trees, in domestic gardens, and in parks. We also present data on shrub and tree regeneration in parks and domestic gardens in the city. Indications are that the more sensitive, less intrusive management of urban environments, combined with the greater density of indigenous seed sources, has allowed regeneration of a wide range of indigenous species across a broad spectrum of habitats – from neglected gardens to pavement cracks to exotic plantations. This is despite the competition from the prodigious seed banks and density of exotic trees, shrubs, and ground covers and albeit minimal impacts of introduced browsing and seed eating mammals. If the present trends continue through appropriate management and facilitation, these tentative signs of native forest regeneration should eventually proliferate into a sustainable mixed origin urban forest that resurrects and preserves the natural character of the region. 相似文献
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Deborah M. Thompson Frank W. Edens Gerald A. LeBlanc R. Michael Roe 《Pesticide biochemistry and physiology》2004,80(3):131-142
Trypsin modulating oostatic factor (TMOF), a peptide hormone originally isolated from the ovaries of adult Aedes aegypti, is currently under commercial development as a new pesticide chemistry with a novel mode of action for the control of larval mosquitoes. The objective of the current research is to evaluate potential risks of the use of TMOF as an insecticide on non-target organisms. TMOF (YDPAP6) was degraded in vitro (as determined by HPLC and LC/MS) to DPAP6, PAP6, and then AP6 by leucine aminopeptidase, a pancreatic enzyme found in the digestive system of vertebrates. The rate of degradation of TMOF and PAP6 was significantly greater than that of DPAP6, while no metabolism of AP6 was found. TMOF technical insecticide was produced on a commercial scale by recombinant yeast (heat-killed before application). The technical TMOF when administered in a single dose by gavage to male and female mice at 2000 mg dry weight/kg body weight produced no negative effects as compared to controls up to 12 days after treatment. When male and female mallard ducks were treated by gavage with 1250 mg dry weight of technical TMOF/kg body weight each day for 5 days, again no toxic effects were noted through 35 days after the last treatment. TMOF technical insecticide was also applied to the shaved skin of male and female rabbits at the rate of 2000 mg/kg for 1-2 days, with no effect. The end point observations in these in vivo experiments were mortality; changes in growth rate, behavior, body structure, and color; and possible lesions observed during necropsy. Finally, Daphnia incubated with technical TMOF in rearing water at the level of 1.0 × 106 yeast cells/ml (10 mg/ml) also demonstrated no negative effects on mortality, growth, molting, time to first brood, and production of viable neonates. It appears from these studies that TMOF can be degraded by vertebrate digestive proteases and technical TMOF is not toxic to the non-target organisms examined. 相似文献
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Equine pituitary pars intermedia dysfunction: current understanding and recommendations from the Australian and New Zealand Equine Endocrine Group 下载免费PDF全文
CJ Secombe SR Bailey MA de Laat KJ Hughes AJ Stewart JM Sonis RHH Tan 《Australian veterinary journal》2018,96(7):233-242
The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder. 相似文献
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Re: Recommendations from the Australian and New Zealand Equine Endocrine Group and the interpretation of plasma endogenous ACTH concentrations for the diagnosis of pituitary pars intermedia dysfunction (PPID) 下载免费PDF全文
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Effect on Rendement Napole genotype on metabolic markers in Ossabaw pigs fed different levels of fat 下载免费PDF全文
H. Lu H. Yan M. G. Ward T. Stewart O. Adeola K. M. Ajuwon 《Journal of animal physiology and animal nutrition》2018,102(1):e132-e138
We investigated effects of Rendement Napole (RN ) genotype on metabolic markers in Ossabaw pigs fed diets with different levels of dietary fat. Thirty‐two pigs, belonging to either the wild‐type (WT , rn+/rn+) or carrier (CAR , RN ?/rn+) genotypes (n = 16/genotype), were divided into two dietary groups, (high fat [HF ] or low fat [LF ]) diets, for 12 weeks (n = 8 pigs/genotype/diet) after which pigs were killed for gene expression analysis by RT ‐PCR . Feeding HF diet caused increased daily gain (ADG , p < .05) and final body weight (BW ) (p < .05) in comparison with the LF diet (p < .05). Feed efficiency (gain:feed) was higher (p < .05) in pigs on the HF and was higher (p < .05) in CAR pigs compared to WT . There was genotype × diet interaction (p = .05) on final BW such that CAR animals on LF diet had the same final BW as animals of both genotypes on HF diet. Carrier pigs on LF diet had higher (p < .05) average daily gain and gain:feed than WT pigs. There was a trend (p < .08) for a higher feed consumption in pigs on the LF diet. Backfat thickness was higher (p < .01) in pigs on the HF diet. Serum triglyceride was higher (0.62 vs. 0.33 mg/dl, p < .01) in pigs on HF diet. Serum insulin was higher (p < .05) in CAR versus WT pigs (0.40 vs. 0.015 μg/ml). Pigs on the HF diet had a higher (p < .05) serum insulin compared to those on the LF diet (0.032 vs. 0.023 μg/ml). Carnitine palmitoyl transferase 1‐alpha was higher (p < .05) in the longissimus dorsi and semitendinosus muscles of pigs on HF diet. Acyl‐CoA oxidase I was elevated (p < .05) in the liver of pigs on HF diet. Fatty acid synthase was lower in the longissimus dorsi muscle, liver and mesenteric fat (p < .05) of carrier pigs. The RN gene regulates specific metabolic markers in the Ossabaw pigs. 相似文献