Milk production in early lactation in a dairy herd following supplementation with iodine, selenium and cobalt     

Cook JG  Green MJ 《The Veterinary record》2010,167(20):788-789

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Effects of rapid global warming at the Paleocene-Eocene boundary on neotropical vegetation     

Jaramillo C  Ochoa D  Contreras L  Pagani M  Carvajal-Ortiz H  Pratt LM  Krishnan S  Cardona A  Romero M  Quiroz L  Rodriguez G  Rueda MJ  de la Parra F  Morón S  Green W  Bayona G  Montes C  Quintero O  Ramirez R  Mora G  Schouten S  Bermudez H  Navarrete R  Parra F  Alvarán M  Osorno J  Crowley JL  Valencia V  Vervoort J 《Science (New York, N.Y.)》2010,330(6006):957-961

Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.  相似文献   

Above- and belowground tree biomass models for three mangrove species in Tanzania: a nonlinear mixed effects modelling approach     

Marco Andrew Njana  Ole Martin Bollandsås  Tron Eid  Eliakimu Zahabu  Rogers Ernest Malimbwi 《Annals of Forest Science》2016,73(2):353-369

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Assessment of the welfare of dairy cattle using animal-based measurements: direct observations and investigation of farm records     

Whay HR  Main DC  Green LE  Webster AJ 《The Veterinary record》2003,153(7):197-202

A protocol was developed by consultation with experts on the welfare of cattle to use direct observations of cattle and an examination of farm records to assess welfare. Fifty-three dairy farms in England were visited and assessed during the winter of 2000/01. The findings were compiled and the results of the welfare measurements were examined by 50 experts who indicated at what level they considered that improvement was required. More than 75 per cent of them considered that 32 of the 53 farms needed to take action to reduce the incidence of mastitis, and that at least 42 of the farms needed to take action to reduce the prevalence of lameness, overgrown claws, swollen and ulcerated hocks, and injuries from the environment.  相似文献   

Dosing regimen and hematologic effects of pentoxifylline and its active metabolites in normal dogs     

Rees CA  Boothe DM  Boeckh A  Wilkie S  Esparza T  Green R 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(2):188-196

The disposition of pentoxifylline and two of its active metabolites (metabolite 1 [M1] and metabolite 5 [M5]) were studied following i.v. (8 mg/kg) and p.o. (30 mg/kg) administration to eight normal dogs using a randomized crossover design. Blood samples were collected at fixed time intervals after drug administration for determination of drug concentrations, platelet aggregation, and plasma fibrinogen. Complete blood counts, serum chemistry profiles, fibrinogen, and urinalysis were monitored at the beginning and end of each phase of the study (p.o. versus i.v. administration). Pentoxifylline was readily metabolized and bioavailable (50% +/- 26%). Both M1 and M5 were present throughout the study, with M5 predominating. Human drug therapeutic concentrations (1,000 ng/ml) were present for 170 +/- 24 minutes following i.v. administration and 510 +/- 85 minutes after p.o. dosing. These findings suggest that a 12-hour dosing regimen is appropriate. None of the dogs experienced any adverse effects after pentoxifylline administration. The lack of hematologic effects suggests that the immunologic effects of pentoxifylline may be of more importance in dogs.  相似文献   

Identification of Fungal rDNA Associated with Soil Suppressiveness Against Heterodera schachtii Using Oligonucleotide Fingerprinting     

Yin B  Valinsky L  Gao X  Becker JO  Borneman J 《Phytopathology》2003,93(8):1006-1013

ABSTRACT To understand the nature of a soil with suppressiveness against Heterodera schachtii, an rDNA analysis was used to identify fungi associated with H. schachtii cysts obtained from soils possessing various levels of suppressiveness. Because H. schachtii cysts isolated from these suppressive soils can transfer this beneficial property to nonsuppressive soils, analysis of the microorganisms associated with the cysts should lead to the identification of the causal organisms. Five soil treatments, generated by mixing different amounts of suppressive and fumigation-induced nonsuppressive soils, were infested with second-stage juveniles of H. schachtii and cropped with mustard-greens. Fungi were identified through an rDNA analysis termed oligonucleotide fingerprinting of ribosomal RNA genes (OFRG). Cysts obtained from soil mixtures consisting of 10 and 100% suppressive soil predominantly contained fungal rDNA with high sequence identity to Dactylella oviparasitica. The dominant fungal rDNA in the cysts isolated from the soil mixtures composed of 0.1 and 1% suppressive soil had high sequence identity to Fusarium oxysporum. Polymerase chain reaction (PCR) amplifications performed with sequence-selective primers corroborated the treatment-specific distribution of rDNA clones obtained by the OFRG analysis. When these sequence-selective PCR primers were used to examine H. schachtii cysts from biocidal soil treatments that produced various levels of suppressiveness, only the D. oviparasitica-like rDNA was consistently identified in the highly suppressive soils.  相似文献   

Environmental fate of metalaxyl and chlorothalonil applied to a bentgrass putting green under southern California climatic conditions     

Wu L  Liu G  Yates MV  Green RL  Pacheco P  Gan J  Yates SR 《Pest management science》2002,58(4):335-342

Putting greens usually receive high inputs of fertilizers and pesticides to meet the high demand for visual quality and to overcome the stress from close mowing and traffic. In this study, two commonly used fungicides, metalaxyl (methyl N-(methoxyacetyl)-N-(2,6-xylyl)-DL-alaninate) and chlorothalonil (2,4,5,6-tetrachloro-1,3-benzenedicarbonitrile), were evaluated for their partitioning and persistence in a bentgrass (Agrostis palustris Huds) putting green under southern California climatic conditions. The putting green site was constructed according to the US Golf Association (USGA) specifications. Lysimeter assemblies installed at the center of each plot were used to monitor the leachate, flux chambers were used to measure volatilization, clippings were collected to determine the residues on grass, and soil cores were sampled to determine residues in the soil profile. Results showed that cumulative volatilization loss accounted for 0.10 and 0.02%, clipping removal 0.11 and 0.13%, and cumulative leaching 0.71 and 0.002% of the applied metalaxyl and chlorothalonil, respectively. The two fungicides were mainly found in the top 10 cm of the soil profile due to the high organic carbon content in the thatch and mat layers. The dissipation half-life was 1.4 days for metalaxyl and 4.9 days for chlorothalonil on grass, shorter than those found in agricultural fields. This study showed that, under normal turf management practices, the offsite transport of the parent fungicides was minimal. Future research should focus on investigating the fate and mobility of the metabolites of the fungicides.  相似文献   

Reproductive performance of the New Zealand flatworm Arthurdendyus triangulatus in earthworm species-poor and -rich habitats at Benmore, Scotland     

Ole M. Christensen  Janice G. Mather 《Pedobiologia》2005,49(5):455-465

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Continental-scale interactions with temporary resources may explain the paradox of large populations of desert waterbirds in Australia   总被引：1，自引：1，他引：0  

D.A. Roshier  A.I. Robertson  R.T. Kingsford  D.G. Green 《Landscape Ecology》2001,16(6):547-556

Arid Australia supports extraordinary numbers of waterbirds. We show that the solution to this seeming paradox lies in considering the availability of temporary wetland habitat in the context of the birds dispersal capability and fluctuations in the abundance of wetlands in time and space. For species with large dispersal capabilities, the Lake Eyre Basin of central Australia, amongst the driest regions on the continent, has the highest habitat availability for waterbirds. Analyses of landscape structure show that the wetlands of the Lake Eyre Basin are highly inter-connected and linked by broad pathways to wetter parts of south-eastern Australia. These analyses illustrate that organism traits and patch dynamics affect realised habitat availability and indicate that the processes that structure populations may operate at much larger spatial scales than those at which humans usually seek to manage the landscape.  相似文献   

Infestation of natural populations of earthworm cocoons by rhabditid and cephalobid nematodes     

Hans Ole KraglundFlemming Ekelund 《Pedobiologia》2002,46(2):125-135

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