A review of potential biodiversity indicators for application in British forests   总被引：6，自引：0，他引：6  

Ferris  R; Humphrey  JW 《Forestry》1999,72(4):313-328

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Stepwise function of natural growth for Scylla serrata in East Africa: a valuable tool for assessing growth of mud crabs in aquaculture          下载免费PDF全文

Per‐Olav Moksnes  David Oersted Mirera  Emma Björkvik  Muumin Iddi Hamad  Humphrey Matalu Mahudi  Daniel Nyqvist  Narriman Jiddawi  Max Troell 《Aquaculture Research》2015,46(12):2938-2953

Predicting growth is critical in aquaculture, but models of growth are largely missing for mud crab species. Here, we present the first model of natural growth in juvenile and adult mud crabs Scylla serrata from East Africa using a stepwise growth function based on data on intermoult periods and growth at moult from field mark‐recapture, pond and laboratory studies. The results showed a sigmoid growth pattern in carapace width and suggest that S. serrata in East Africa will reach 300 g and sexual maturity ~9.9 months after settlement, and a commercial size of 500 g after 12.4 months. Analyses of the literature identified several issues with the common praxis to compare standard growth measures between aquaculture studies with different initial size or growing periods. Using the new growth function to estimate the proportional difference between modelled and obtained growth as an alternative method, we show that growth rates of S. serrata cultured in cage systems, which are dominant in East Africa, was <40% of the estimated natural growth and growth obtained in pond systems. The analysis also indicated that growth rates of S. serrata in Southeast Asia was over 50% higher compared with similar culture systems in East Africa, and that different species of mud crabs had large differences in growth rates. This study shows that growth in the present mud crab aquaculture systems in East Africa is below their expected potential. Further work is needed to identify the factors behind this observation.  相似文献   

Erratum to: Tree-grass coexistence in a flood-disturbed, semi-arid savanna system     

Matthew F. Child  Sue J. Milton  W. Richard J. Dean  Marisa K. Lipsey  James Puttick  Tessa N. Hempson  Gareth K. Mann  Hassan Babiker  Jamshed Chaudrey  Glynis Humphrey  Grant Joseph  Nicola C. Okes  Reda Potts  Thuli Wistebaar 《Landscape Ecology》2010,25(2):327-327

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蓟马取食对苜蓿氨基酸组成及含量的影响     

武杰瑞  刘秉毅  特木尔布和  爽爽  代蕊  张志强 《草地学报》2022,30(1):62-68

为了探究蓟马取食对苜蓿(Medicago sativa L.)氨基酸组成及含量的影响,本研究以'草原2号'(Medicago varia Martin.'Caoyuan No.2')感蓟马品种和'草原4号'(Medicago sativa L.'Caoyuan No.4')抗蓟马品种为材料,分别进行牛角花齿蓟马(Odo...  相似文献   

Porcine intestinal epithelial responses to Campylobacter infection     

Murphy H  Cogan T  Hughes R  Humphrey T 《Comparative immunology, microbiology and infectious diseases》2011,34(6):489-495

Campylobacter infection is estimated to cause diarrhoea in 1% of the population of developed countries every year, but our understanding of this disease has been hampered by a lack of a suitable animal model. Colostrum-deprived piglets have been suggested as models since they produce similar clinical signs to humans when infected but little information currently exists regarding the response of this species to Campylobacter at cellular and molecular level. This study shows that intestinal epithelial cells from both species respond in a similar manner to Campylobacter infection regarding invasion, induction of innate immune response and effect on barrier function.  相似文献   

Getting lost in the matrix? On how the characteristics and arrangement of linear landscape elements influence ecological connectivity     

Anderson  Calum  Travis  Justin M. J.  Palmer  Stephen C. F.  Crick  Humphrey Q. P.  Lancaster  Lesley T. 《Landscape Ecology》2022,37(10):2503-2517

Landscape Ecology - Linear landscape elements (LLEs) such as ditches and hedgerows can increase the ecological connectivity of habitat embedded within agricultural areas by acting as corridors for...  相似文献   

A Placebo‐Controlled,Prospective, Randomized Clinical Trial of Polyethylene Glycol and Methylprednisolone Sodium Succinate in Dogs with Intervertebral Disk Herniation          下载免费PDF全文

N.J. Olby  A.C. Muguet‐Chanoit  J.‐H. Lim  M. Davidian  C.L. Mariani  A.C. Freeman  S.R. Platt  J. Humphrey  M. Kent  C. Giovanella  R. Longshore  P.J. Early  K.R. Muñana 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(1):206-214

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Detection of Paranannizziopsis australasiensis in tuatara (Sphenodon punctatus) using fungal culture and a generic fungal PCR     

S Humphrey  S Alexander  HJ Ha 《New Zealand veterinary journal》2016,64(5):298-300

AIMS: To describe the methods used at the Animal Health Laboratory (AHL, Ministry for Primary Industries) to identify Paranannizziopsis australasiensis.

METHODS: Skin biopsy samples from two adult male tuatara were submitted to the AHL in March 2014. Approximately half of each sample was processed for fungal culture and incubated on mycobiotic agar containing cycloheximide at 30°C. Following morphological examination of the culture products, DNA was extracted from suspect colonies. PCR was used to amplify the internal transcribed spacer (ITS) region of fungal rRNA using primers ITS1 and ITS4. Positive amplicons were subjected to DNA sequencing and the results were compared to published sequences. In addition, DNA was extracted from the remaining skin samples and the same PCR was carried out to compare the results.

RESULTS: After 7 days of incubation, colonies morphologically resembling P. australasiensis were observed. DNA extracted from these isolates tested positive for P. australasiensis by PCR and DNA sequencing. Samples of DNA extracted directly from the infected skin samples tested negative for P. australasiensis using the generic fungal PCR.

CONCLUSIONS AND CLINICAL RELEVANCE: Isolation and identification of P. australasiensis was carried out using a combination of fungal culture and molecular testing available at AHL. Results were available in significantly less time than in the past, when isolates had to be sent overseas. PCR and sequencing of fungal isolates is a valuable tool for identification of species that have few, if any, unique macroscopic or microscopic features to aid identification. Further sampling from captive and wild New Zealand reptiles will provide important information on the epidemiology of P. australasiensis, and the conservation and management implications for tuatara and other native reptile species.  相似文献   

Diversifying native pinewoods using artificial regeneration     

Ogilvy  Tanya K.; Legg  Colin J.; Humphrey  Jonathan W. 《Forestry》2006,79(3):309-317

Little is known about broadleaf establishment within the nativepinewoods of Scotland, yet such information is critical to currentrestoration initiatives. A 2-year field trial was set up toassess the growth and performance of seedlings of four broadleavedspecies within different developmental stages of Pinus sylvestris(Scots pine) woodland in the Scottish Highlands. The developmentalstages included stem initiation (establishment stage), stemexclusion (thicket/pole stage) and canopy break up (old-growthcanopy), providing sites of varying shade and resource availability.It was predicted that differences in establishment between siteswould occur due to species-specific differences in ‘tolerance’of shade, low-nutrient availability and poor soil drainage.Analysis of trial results showed high survival but growth rates(relative stem height and basal diameter growth) declined rapidlyin year two. In year two, Ilex aquifolium achieved the highestmean growth rates in the stem exclusion stands (average 15 percent light) where there was a lower percentage of Phytomyzailicis (holly leaf miner) infection and frost damage. Sorbusaucuparia exhibited generalist behaviour with similar growthand performance across all stand treatments. Betula pubescensmaintained similar growth rates across stand types but was moresusceptible to insect damage in deeper shade. Overall, Alnusglutinosa grew more successfully than the other species andachieved highest mean growth rates in canopy break up (average44 per cent light) and stand initiation (average 71 per centlight) stages. Broadleaf establishment within pinewood standsis challenging on account of acidic nutrient-poor soil regimes,and in places, poor drainage, aggressive understorey competitionand canopies that restrict light availability and insect herbivory.Forest restoration techniques, including matching species tosite, accelerating establishment and using framework species(individuals of high field performance that are able to restoresite productivity and nutrient cycles), are discussed.  相似文献   

Antigenic cross-reactivity among avian pneumoviruses of subgroups A,B, and C at the matrix but not nucleocapsid proteins     

Lwamba HC  Halvorson DA  Nagaraja KV  Turpin EA  Swayne D  Seal BS  Njenga MK 《Avian diseases》2002,46(3):725-729

Earlier findings from our laboratory based on analysis of nucleotide and predicted amino acid sequence identities of 15 avian pneumoviruses (APVs) isolated from the United States (subgroup C) demonstrated that the viruses were phylogenetically separated from the European subgroup A and subgroup B viruses. Here, we investigated whether viruses from the three subgroups were cross-reactive by testing field sera positive for each of the APV subgroups in an enzyme-linked immunosorbent assay (ELISA) test with recombinant matrix (M) and nucleoprotein (N) proteins generated from a Minnesota APV isolate (APV/MN2A). Sera from turkeys infected with APV subgroup A, B, or C reacted with recombinant M protein derived from APV/MN2A. In contrast, recombinant N protein from APV/MN2A virus was reactive with sera from subtypes A and C viruses but not from subtype B virus. The results illustrate that viruses from the three APV subtypes share antigenic homology, and the M protein-based ELISA is adequate for monitoring APV outbreaks but not for distinguishing between different subtypes.  相似文献