7,472 research outputs found
Nodular gill disease: a unique form of proliferative gill disease in rainbow trout, Salmo gairdneri Richardson
No full textIn an outbreak of proliferative gill disease in laboratory rainbow trout fingerlings lesions were multifocal among filaments and uniquely severe in the distal region of affected filaments, forming nodules. This contrasted with the more common forms of proliferative gill disease in Ontario, such as bacterial gill disease, in which lesions are diffuse along and among filaments. The cause is unknown, although cells with a very distinctive morphology were closely associated with the lesions..RE: 22 ref.; SC: ZA; CA; VE; 0V; 0ISource type: Electronic(1) http://upei-resolver.asin-risa.ca?sid=SP:CABI&id=pmid:&id=&issn=0140-7775&isbn=&volume=8&issue=6&spage=511&pages=511-522&date=1985&title=Journal%20of%20Fish%20Diseases&atitle=Nodular%20gill%20disease%3a%20a%20unique%20form%20of%20proliferative%20gill%20disease%20in%20rainbow%20trout%2c%20Salmo%20gairdneri%20Richardson.&aulast=Daoust&pid=%3Cauthor%3EDaoust%2c%20P%20Y%3bFerguson%2c%20H%20W%3C%2Fauthor%3E%3CAN%3E19862272504%3C%2FAN%3E%3CDT%3EJournal%20article%3C%2FDT%3
Pathology of bacterial gill disease: sequential development of lesions during natural outbreaks of disease
No full textThe sequential pattern of bacterial colonization and the sequential development of branchial lesions during typical outbreaks of bacterial gill disease (BGD) was studied among 4 groups of commercially reared rainbow trout fingerlings, Oncorhynchus mykiss. During a 5-month monitoring regime, before the onset of natural outbreaks of BGD, gill morphology of examined fish remained unaltered. Bacterial colonization of the gills was immediately preceeded by several gill changes which were widely present in fish from all groups under study. These changes, which were detectable at the ultrastructural level only, included cytoplasmic blistering and degeneration of the microridges of the superficial filament epithelium, in addition to slight topographical irregularity of the filament tips suggestive of mild hyperplasia. Bacterial colonization began at these altered filament tips before spreading to more proximal regions of the filament and adjacent lamellar surfaces. Explosive increases in proportional morbidity and mortality coincided with the development of the following gill lesions: extensive bacterial colonization of lamellar surfaces, lamellar epithelial hydropic degeneration and necrosis, and lamellar oedema. In contrast, gill lesions such as lamellar fusion, epithelial hyperplasia and various metaplastic responses were detected either as subacute (3-5 days) or chronic (7-14 days) changes. The role of epithelial necrosis as an important event during BGD is discussed as a possible mechanism leading to development of sub-acute and chronic gill lesions..RE: 37 ref.; SC: CA; VE; 0I; ZA; 0VSource type: Electronic(1) http://upei-resolver.asin-risa.ca?sid=SP:CABI&id=pmid:&id=&issn=0140-7775&isbn=&volume=14&issue=1&spage=21&pages=21-32&date=1991&title=Journal%20of%20Fish%20Diseases&atitle=Pathology%20of%20bacterial%20gill%20disease%3a%20sequential%20development%20of%20lesions%20during%20natural%20outbreaks%20of%20disease.&aulast=Speare&pid=%3Cauthor%3ESpeare%2c%20D%20J%3bFerguson%2c%20H%20W%3bBeamish%2c%20F%20W%20M%3bYager%2c%20J%20A%3bYamashiro%2c%20S%3C%2Fauthor%3E%3CAN%3E19912256145%3C%2FAN%3E%3CDT%3EJournal%20article%3C%2FDT%3
Potential for recovery in nodular gill disease of rainbow trout, Salmo gairdneri Richardson
No full textNodular gill disease characterized by severe multifocal epithelial hyperplasia was diagnosed in a group of rainbow trout fingerlings. Gills of a large proportion of fish transferred from the affected tank to smaller aquaria showed a marked decrease in severity of the lesions after 2 months. Repair of hyperplastic lesions may occur in various forms of proliferative gill disease, provided that the basement membrane lining the filaments and lamellae remains intact..RE: 11 ref.; SC: ZA; CA; VE; 0V; 0ISource type: Electronic(1) http://upei-resolver.asin-risa.ca?sid=SP:CABI&id=pmid:&id=&issn=0140-7775&isbn=&volume=9&issue=4&spage=313&pages=313-318&date=1986&title=Journal%20of%20Fish%20Diseases&atitle=Potential%20for%20recovery%20in%20nodular%20gill%20disease%20of%20rainbow%20trout%2c%20Salmo%20gairdneri%20Richardson.&aulast=Daoust&pid=%3Cauthor%3EDaoust%2c%20P%20Y%3bFerguson%2c%20H%20W%3C%2Fauthor%3E%3CAN%3E19862285526%3C%2FAN%3E%3CDT%3EJournal%20article%3C%2FDT%3
Measurements of the branchial sieve of sardine (Sardinops sagax ocellatus) from the west and south coasts of southern Africa
No full textIncludes abstract.Includes bibliographical references (p. 40-46).Branchial sieves of southern African sardine (Sardinops sagax ocellatus) were collected from three geographical regions along the southern African coast: Namibia, the south coast and the west coast of South Africa. Sardine from Namibia represented the northern Benguela upwelling ecosystem while sardine from the west and south coasts of South Africa represented the southern Benguela upwelling ecosystem. Morphometric measurements (gill arch length and gill raker spacing) and counts (number of gill rakers) of branchial sieves on the left side of the first gill arch were taken to determine whether the sardine from these regions have different branchial sieve structures
SC author and illustrator Kate Salley Palmer signing book
No full textPhotograph of SC author and illustrator Kate Salley Palmer signing boo
Book signing by SC author and illustrator Kate Salley Palmer
No full textPhotograph of Book signing by SC author and illustrator Kate Salley Palme
Pathology of bacterial gill disease: ultrastructure of branchial lesions
No full textThe range of branchial lesions associated with bacterial gill disease (BGD) in rainbow trout, Oncorhynchus mykiss, was investigated through the ultrastructural examination of 23 separate outbreaks of the disease condition within commercially reared stocks. Diseased branchial tissues had a large and diffusely distributed monomorphic population of filamentous bacteria which were strictly epicellular. Although bacterial colonization was restricted to the branchial cavity, it was neither site nor cell specific: epithelial and chloride cells of the lamellae, filaments and lining tissues of the branchial cavity were all uniformly affected. The bacteria possessed an extensive glycocalyx which appeared to facilitate adhesion to the apices of the microridged sub-unit modification of the cell surface. Sites of colonization were accompanied by a diffuse pattern of cellular degeneration and necrosis that was generally restricted to the outer layers of epithelium. The polarity and nature of these changes suggest that the mechanism of interaction between the bacteria and host cells includes progressive hydropic changes as a sequel to primary membrane damage and consequent increased cell permeability. These cellular changes were accompanied by the range of stereotypical responses of the gill to damage frequently reported for BGD including lamellar fusion, epithelial hyperplasia, and squamous and mucous cell metaplasia, in addition to lamellar spongiosis..RE: 42 ref.; SC: CA; VE; 0I; ZA; 0VSource type: Electronic(1) http://upei-resolver.asin-risa.ca?sid=SP:CABI&id=pmid:&id=&issn=0140-7775&isbn=&volume=14&issue=1&spage=1&pages=1-20&date=1991&title=Journal%20of%20Fish%20Diseases&atitle=Pathology%20of%20bacterial%20gill%20disease%3a%20ultrastructure%20of%20branchial%20lesions.&aulast=Speare&pid=%3Cauthor%3ESpeare%2c%20D%20J%3bFerguson%2c%20H%20W%3bBeamish%2c%20F%20W%20M%3bYager%2c%20J%20A%3bYamashiro%2c%20S%3C%2Fauthor%3E%3CAN%3E19912256144%3C%2FAN%3E%3CDT%3EJournal%20article%3C%2FDT%3
Patógenos em ostras na Ilha de Santa Catarina-SC e no Estuário do Rio Pacoti-CE, com ênfase no protozoário Perkinsus
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Aqüicultura, Florianópolis, 2010A perkinsiose, enfermidade causada pelo protozoário Perkinsus sp., é responsável por mortalidades de moluscos marinhos em todo o mundo. O presente estudo objetivou verificar a presença de patógenos com ênfase em Perkinsus em ostras de Santa Catarina/SC e do Ceará/CE, Brasil. Em SC, as ostras Crassostrea rhizophorae (costão) e Crassostrea gigas (cultivo) foram coletadas no Sambaqui e Ribeirão da Ilha, em março/2008 e abril/2009 (N= 1200). No CE, as ostras C. rhizophorae foram coletadas em 3 pontos do Estuário do Rio Pacoti, em agosto/2008 e dezembro/2009 (N= 900). As técnicas utilizadas foram análise macroscópica, histologia, cultivo em meio líquido de tioglicolato, reação em cadeia da polimerase (PCR), clonagem e sequenciamento de uma região identificada de Perkinsus. Os resultados nas ostras estudadas mostraram: hipertrofia gamética, a presença de bactérias do tipo rickettsia; protozoários: Perkinsus, Nematopsis, Trichodina, Sphenophrya, Ancistrocoma e Steinhausia. As hipertrofias e bactérias foram detectadas nas ostras de SC e Perkinsus somente nas ostras do CE. Os metazoários observados foram poliquetas Polydora, Urastoma, Tylocephalum, copépode possivelmente do gênero Pseudomyicola e, nas ostras do Ceará, larvas de digenéticos. Os patógenos não foram associados a danos significativos nos tecidos das ostras, em SC e CE. As ostras do CE foram diagnosticadas com Perkinsus sp. (5,8% em 2008 e 5,1% em 2009). A PCR com iniciadores específicos seguida do sequenciamento confirmou se tratar do gênero Perkinsus, porém ainda não foi possível confirmar a espécie
Morphological changes in rainbow trout (Oncorhynchus mykiss) gill epithelia following repeated intermittent exposure to chloramine-T
No full textChloramine-T is a widely used prophylactic and therapeutic agent in freshwater aquaculture (mainly against bacterial gill disease). The effects of repeated intermittent exposure of healthy rainbow trout (Oncorhynchus mykiss) fingerlings to sublethal concentrations of chloramine-T (0,5, 10, or 20 mg/litre) twice weekly in 1-h pulses at 11 degrees C for 4 weeks in a replicate-tank facility were examined. Gills were excised from subsamples of fish before exposure and at the end of the 4-week experimental period. Tissue was fixed and processed for light microscopy and transmission and scanning electron microscopy. The gill epithelium from fish treated with 10 and 20 mg/litre chloramine-T appeared swollen and vacuolated, with extensive intercellular oedema. There was a significant reduction in the number of lamellar mucous cells and an apparent increase in the numbers of chloride cells. Chloride cells from both the base of the lamella and the lamellar surface of gills exposed to chloramine-T had an increase in the area of the apical plasmalemma after treatment with 10 and 20 mg/litre, and a reduction in the thickness of the apical plasmalemma-associated glycocalyx. These morphological changes are consistent with a compensatory mechanism for the remedial uptake of ions, suggesting that chloramine-T increased epithelial ion permeability coincident with a possible influx of water leading to intercellular oedema. Chloride cell proliferation and intercellular oedema may also have affected gas exchange across the branchial epithelium..RE: 53 ref.; SC: BE; ZA; CA; VE; 0I; EC; 0VSource type: Electronic(1
Análise arima de dados meteo-oceanográficos
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Ambiental.Um estudo do mecanismo gerador das componentes meteorológicas que afetam o nível do mar é proposto através da utilização de modelos ARIMA (autorregressive integrated moving average). Séries temporais da temperatura do ar, pressão atmosférica, da componente meridional do vento e do nível do mar foram aquisitadas em São Francisco do Sul-SC, no período de 14 de julho a 15 de dezembro de 1996, e reamostradas a cada seis horas para melhor avaliar as componentes de baixa freqüência. As séries se mostraram não estacionárias na média, impondo a necessidade de integração. Não foi possível identificar uma não estacionaridade da variância devido ao comprimento insuficiente dos registros utilizados. Nos modelos de ordem 2 a estrutura de recorrência entre dois sistemas frontais é reconhecida através do modo associado aos dois pólos do polinômio. Os modelos AR(4) de todas as variáveis consideradas conseguem reconstruir também a evolução do sistema in situ, de período aproximado de 2,5 dias, por meio da segunda dupla de pólos. Modelos autorregressivos de ordem superior poderiam melhorar a identificação e a reconstrução desses ciclos, mas não conseguem convergir devido a não estacionaridade. Apesar disso, modelos de baixa ordem, com dois parâmetros apenas, conseguem fazer previsões aceitáveis até 24 horas, o que demonstra as possibilidades da metodologia
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