Pteridium


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Related to Pteridium: Bracken fern

Pteridium

a fern in the family Dennstadiaceae.
The fern is classified by some authorities as more than one species including: P. aquilinum, P. esculentum, P. revolutum, P. yarrabense. Called also bracken. It causes poisoning in several unique ways: (1) Ingestion by cattle over a short period causes depression of bone marrow activity, leading to pancytopenia evidenced principally as ecchymotic hemorrhages in mucosae and terminal septicemia. Severe diarrhea and dysentery may be terminal events. Ingestion over a long period causes proliferative lesions in and bleeding from the urinary bladder mucosa. See enzootic hematuria. Bright blindness of sheep also occurs when intake of bracken is prolonged. There is also a relationship between access to bracken and a higher than normal occurrence of intestinal carcinoma in ruminants. (2) A thiaminase in bracken causes a clinical syndrome of thiamin deficiency in horses. Signs are muscle tremor, incoordination, frequent falling and bradycardia and cardiac irregularity.
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Pteridium aquilinum.By permission from Knottenbelt DC, Pascoe RR, Diseases and Disorders of the Horse, Saunders, 2003
References in periodicals archive ?
Perfil proteico en hembras bovinas expuestas al consumo de Pteridium aquilinum en el municipio Nirgua, estado Yaracuy.
Alteracoes hematologicas, bioquimicas, urinarias e histopatologicas na intoxicacao natural em bovinos pela samambaia Pteridium aquilnum (L.
10 m, subespontaneo en comunidad arbustiva adscribible a la clase Cytisetea scopario-striati, sobre suelo fresco y en compania de Cytisus scoparius, Pteridium aquilinum subsp.
Especie Porcentaje (%) Cevendischia bracteata 3,5 Lycopodium jussiaei 3,9 Dichromena ciliata 4,4 Befaria resinosa 4,9 Calea peruviana 5,1 Rhynchospora macrochaeta 6,0 Calamagrostis intermedia 8,5 Pteridium aquilinum 9,3 Andropogon bicornis 9,9 Hypoxis decumbens 14,7 b.
The seedling intolerance to shading was also evidenced by Silva Matos and Belinato (2010) who observed high seedling mortality in sub-plots with Pteridium arachnoideum after a year of sampling.
Pteridium is a well-known weed worldwide, but most knowledge has been derived from studies in the northern hemisphere (Marrs and Watt, 2006).
The occurrence of these acidophilous beech forests can be recognized in the pollen diagrams (Figures 3 and 4) by relatively high percentages of Betula (35% in sample 5), Abies (~1%), Castanea (1-3%), Carpinus betulus (1-2%), Fabaceae (6-9%) and Pteridium aquilinum (5-14%), although Fagus (6-20%) is the dominant pollen type in the dataset characterizing cluster 2 of the HCA (Figure 6).
Cirsium oleraceum Cirsium palustre Deschampsia caespitosa + Drosera rotundifolia Epilobium adenocaulon Epilobium angustifolium + Epilobium hirsutum Epilobium montanum Eriophomm vaginatum + + + + Galinsoga ciliata Lycopodium annolinum Melampyrum pratense + Mycelis muralis Orthilia secunda Oxycoccus palustris + Poa trivialis Pteridium aquilinum + Pyrola rotundifolia Rubus chamaemorus Senecio vulgaris Taraxacum spp.
This increase in species number was mainly determined by spread out of pioneer early succesional herb species (Calamagrostis epigejos, Equisetum hyemale, Pteridium aquilinum, Rubus idaeus, R saxatilis, Scorzonera humilis, Solidago virgaurea, Ceratodon purpureus, Polytrichum juniperinum).
En este sentido el unico co-factor identificado hasta ahora en los procesos carcinogenicos asociados a la infeccion por BPV es la ingestion de helechos del genero Pteridium.