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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estudo qualitativo e quantitativo da helmintofauna dos peixes Scomberomorus cavalla (Cuvier) e Scomberomorus maculatus (Mit-Chill) no litoral do Ceará, Brasil / Qualitative and quantitative study of the helminth fauna of Scomberomorus cavalla (Cuv.) e Scomberomorus maculatus (Mitch.) in Ceará Coast

Klein, Vera Lucia Mota January 1975 (has links)
Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2017-07-24T23:02:58Z No. of bitstreams: 1 200781.pdf: 2703929 bytes, checksum: d2ee131d8ae3372359b424e0732625b4 (MD5) / Made available in DSpace on 2017-07-24T23:02:58Z (GMT). No. of bitstreams: 1 200781.pdf: 2703929 bytes, checksum: d2ee131d8ae3372359b424e0732625b4 (MD5) Previous issue date: 1975 / Análise qualitativa e quantitativa dos helmintos que se encontravam infestando, 65peixes das espécies Scomberomorus cavalla (Cuvier) e 65 de Scomberomorus maculatus (MitChill) na costa do Ceará. Foi observado que entre as duas espécies hospedeiras, a ca­vala foi a que apresentou maior Índice de parasitismo.Não foi comprovada qualquer influência do mês do ano, sexo ou idade do hospedeiro, na taxa de infestação helmíntiba. O grupo de helminto que mostrou o maior índice de infestação, foi o de nematódeo, representado 90,01% dos vermes da cavala e 86,34% da serra. Os helmintos encontravam-se em todos os Órgãos dos peixes, principalmente no estômago, onde eles se encontravam em maior número e mais frequentemente. Conclui-se que o termo “marca biológica”, seja aplica­do ao conjunto de parasitas que apresentaram maior lindice de infestação e não para cada espécie isoladamente. / ln this paper the author presents qualitative and quantitative analysis of the helminths parasites of Scomberomorus cavalla (Cuv.) e Scomberomorus maculatus (Mitch.) in Ceará Coast. Based on earlier on the host species in Ceará, the author adds biological data also refering to these species. It is shown through tables and graphics the helminths with the highest infestation frequency as well as the most infected parts. Of the hosts samples, Scomberomorus cavalla (Cuv.) presented the highest parasite índex. The infestation proved not to be due to the month of the yeat the samples were captured, age or sex of the hosts. The group which showed the highes·t infestation level in both host species, was composed by the nematodes, represented by 90,01% of helminths recovered from king mackerel and 86,34% from spanish mackerel. The helminths were recovered from all the parts of the body, mainly from the stomach, where they appered in great number and higher frequency. Prosohynchus atlanticus manther, 1940 and Rhadinorhynchus prsitis (Rudolphi, 1802), 1911 are fereded for the first time in Brazil. The conclusion suggests that the designation "biological tags" should be applied to the recovered helminths as a whole and not to a single species.
2

Biology and population dynamics of the King Mackerel (Scombereomorous commerson, Lacepede, 1800) off the coast of Natal .

Govender, Anesh. January 1992 (has links)
This thesis provides a study on aspects of the biology and population dynamics of Scomberomorus commerson off the south east coast of southern Africa. This is necessary for the evaluation of the current management policies and for the selection of the "best" management strategy for this species off the coast of Natal. The current status of S. commerson off the Natal coast was assessed in terms of yield-per-recruit and spawning biomass-per-recruit analyses. Input parameters to these per-recruit models include growth and mortality rates and basic biological data. Estimates of these parameters and the methods employed are detailed in the thesis . S. commerson has a protracted spawn ing period rang ing from November to March. The principal spawning area is Mozambique. Fifty percent sexual maturity is attained at 1096mm and 706mm(FL) for females and males, respectively. The, ratio of males to females in the sampled catches is approximately 1:2 with females attaining a significantly larger mean size: females (926mm,FL) and males (898mm , FL). The masslength relationsh ip for both sexes can be described by the following equation: Ma s s ( g ) = O.1353X10-5 • [FL(mm) J3.25 15 Growth parameter estimates for the combined sexes were estimated from a lengthbased as well as an age-based method. An objective technique was utilised to determine which growth function best describes the age-length data of S. commerson. Age data were obtained from otolith readings. The precision of otolith readings was described by an index. This index, the average percent error, which is equal to 20.25%, is higher than that recorded in other studies. Two opaque bands are laid down annually. This was validated by marginal increment analyses as well as from tagging data. The age-length relationship , assuming biannual periodicity of the opaque band, is best described by a Von Bertalanffy growth function: L age(mm, FL) = 134 4mm (l-e ...{).292 yr-'Cage-+2.999 yrs») The instantaneous natural mortality rate (M) was estimated using two different techniques: the Pauly equation and the Rihkter and Efanov equation. The former equation was very sensitive to changes in the mean environmental temperature and both techniques produced different estimates. The average of both methods was, therefore, taken as an estimate of M which is 0.5 yr'. The instantaneous fishing mortality rate (F) is currently estimated to be 0.25 vt", This estimate is, however, positively biased as the effects of emigration have not been taken into account. The per-recru it analyses were conducted for three different growth equations for the same values of F and M, age-at-maturity and age-at-first-capture. For all growth equations the yield-per-recruit increased with increased fishing with maximum yield-perrecruit attained either at infinite F or at very high values of F (> 5 yr'), FO.1 was attained between 0.6 and 0.8 v' for all growth equations. The Von Bertalanffy growth function, assuming annual periodicity of the opaque band, was the most unrealistic. It predicted a virtual collapse of the fishery When F=M and a reduction of the spawning biomass to 50% of its unfished level at F=0.1 yr'. The length based derived growth equation and the Von Bertalanffy growth function, assuming biannual periodicity of the opaque band, predicted that spawning biomass dropped to 50% of the pristine level at F=0.19 and 0.16 vr' . respectively. It is believed that the current restrictions on sport catches of 10 fish/person/day offers adequate protection for the Natal king mackerel stock. These restrictions should be maintained in Natal. However, if fishing effort on this species continues to increase (as is anticipated in an open access fishery) or if there is increased commercial interest or if there is renewed fishing in Mozambique, a minimum size is recommended to adequately protect the spawning stock. Such a minimum size should be implemented in Mozambique which is the principal spawning area for king mackerel. Setting a minimum size in Natal, above the size-at-50% maturity may substantially reduce catches in the short and medium term because at least 90% of the catch currently taken will be inaccessible to fishermen. Restrictions of king mackerel catches in Natal, alone, is not considered a viable management option as Natal's commercial and to a certain extent recreational fishermen may turn to Mozambican waters to harvest king mackerel. Management options should be implemented and enforced both in Natal and Mozambique. / Thesis (M.Sc.)-University of Natal, Durban.
3

Subsídios para a conservação de vertebrados marinhos: identificação molecular e monitoramento do comércio online

Falcão, Luara Hanna Oliveira January 2017 (has links)
FALCÃO, L. H. O. Subsídios para a conservação de vertebrados marinhos: identificação molecular e monitoramento do comércio online. 2017. 81 f. Dissertação (Mestrado em Ciências Marinhas Tropicais) - Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by Geovane Uchoa (geovane@ufc.br) on 2017-05-31T12:46:05Z No. of bitstreams: 1 2017_dis_lhofalcao.pdf: 2926405 bytes, checksum: 7eb88d25abc7f7eb60079322832cae55 (MD5) / Approved for entry into archive by Nadsa Cid (nadsa@ufc.br) on 2017-07-07T16:32:39Z (GMT) No. of bitstreams: 1 2017_dis_lhofalcao.pdf: 2926405 bytes, checksum: 7eb88d25abc7f7eb60079322832cae55 (MD5) / Made available in DSpace on 2017-07-07T16:32:39Z (GMT). No. of bitstreams: 1 2017_dis_lhofalcao.pdf: 2926405 bytes, checksum: 7eb88d25abc7f7eb60079322832cae55 (MD5) Previous issue date: 2017 / According to the International Union for the Conservation of Nature (IUCN) there is currently 12,221 endangered species and another 11,029 vulnerable species, globally. Some of these species are highly valuable. Whale meet, elephant ivory, rhino horn, sawfish rostrum, and shark fin are examples of illegally traded items. The fact that these trades are based on animal parts makes difficult the monitoring of species involved. This is because animal parts lack most of diagnostic characters that may permit species identification. In the case of highly valuable frozen fish fillet, as for example the one from the Caribbean Snapper, this lack of diagnostic characters permits a substitution fraud. In this kind of fraud, a low valuable species is trade under the name of a highly valuable species. Moreover, this trade does not only occur in marketplaces or so. It also occurs through virtual or online trade. Given this threatening situation, the development of research on identification of animal parts and trade monitoring are needed. In this context, the goal of the present study was to provide new tools against illegal trade of endangered marine vertebrates, with emphasis on cetaceans, snappers and the batoids known as sawfish. The present study presents mitochondrial DNA Cytochrome c Oxidase subunit I (COI) DNA sequences useful for identification of seven cetacean species from the West Atlantic (Canada and Brazil). In addition, prospective Polymerase Chain Reaction-Restriction Fragment Length Polimorphism (PCR-RFLP) molecular markers are also described for identification of the Caribbean Red Snapper (Lutjanus purpureus) from northern and northeastern Brazil. About the sawfish, here it is described the current status of an ongoing online trade of isolated rostra. Based on roughly one year of monitoring and 402 isolated rostra recorded, it was found that sawfish rostra involved in this kind of trade cost US$ 676.80 a piece, in average. The trade website eBay is responsible for most of the sawfish rostra that is illegally available for international delivery. Keywords: endangered species, illegal trade, conservation, cetacean, Red snapper, sawfish / Segundo a União Internacional para a Conservação da Natureza (UICN), existem atualmente um total de 12.221 espécies em situação de ameaça e outras 11.029 espécies consideradas vulneráveis, globalmente. Algumas dessas espécies possuem alto valor comercial. Produtos como carne de baleia, marfim do elefante, chifre do rinoceronte, rostro de peixe-serra e barbatanas de tubarão são exemplos de produtos comercializados de forma ilegal. O fato desse comércio ser voltado para partes de animais (barbatanas, carne, filés congelados, etc) dificulta a fiscalização dessa atividade. Isto porque espécimes nestas condições estão desprovidos de suas principais características morfológicas, o que frequentemente impede uma identificação. No caso dos filés congelados de peixes com elevado interesse comercial (Ex. pargo), a falta de caracteres morfológicos no produto final permite a ocorrência de fraude de substituição, onde uma espécie menos valorizada (mais barata) é comercializada com o nome de outra espécie de maior valor. E este comércio se dá não apenas de forma presencial ou física, mas também através de comércio virtual - em lojas e sites online. Dada as situações de ameaça, pesquisas que visem a produção de ferramentas que auxiliam a identificação de partes animais e monitoramento de comércio são necessárias. Dentro desse contexto, o objetivo do presente estudo foi fornecer subsídios para o combate contra o comércio ilegal de animais marinhos ameaçados, com ênfase nos cetáceos, no pargo e nas raias conhecidas como peixes-serra. Este estudo contribui com sequências do gene Citocromo c Oxidase subunidade I (COI) de sete espécies de cetáceos do Atlântico Oeste (Canadá e Brasil) que são úteis para identificação de espécies. Adicionalmente, marcadores moleculares do tipo PCR-RFLP (Reação da Cadeia em Polimerase - Polimorfismo no Comprimento de Fragmentos de Restrição) também são descritos para identificar o pargo (Lutjanus purpureus) da costa norte do Brasil. Quanto ao peixe-serra, aqui está descrito o estado atual de um comércio online de rostros isolados. Baseado em aproximadamente um ano de monitoramento e 402 rostros isolados registrados, foi observado que rostros de peixe-serra envolvidos nesse tipo de comércio custam em média US$ 676,80 a unidade. O site de comércio online eBay é responsável pela maior parte dos rostros de peixe-serra que estão ilegalmente disponíveis para entrega internacional. Palavras-chave: espécies ameaçadas, comércio ilegal, conservação, cetáceos, pargo e peixeserra.
4

Filmes e revestimentos do Caranguejo-Uçá (Ucides cordatus) com aplicação em postas de serra (Scomberomorus brasiliensis) congeladas. / Films and coating of the Crab-Uçá (Ucides cordatus) with application in files (Scomberomorus brasiliensis) frozen.

Vale, Diego Alves do January 2017 (has links)
VALE, Diego Alves do. Filmes e revestimentos do Caranguejo-Uçá (Ucides cordatus) com aplicação em postas de serra (Scomberomorus brasiliensis) congeladas. 2017. 95 f. Dissertação (Mestrado em Engenharia de Pesca)-Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by ROGÉRIA MARIA OLIVEIRA (rsetubaloliveira@yahoo.com.br) on 2017-09-15T18:06:06Z No. of bitstreams: 1 DISSERTAÇÃO_DIEGO ALVES DO VALE.pdf: 1123185 bytes, checksum: 54612d838ec28b9e6b930c76d7018bb1 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2017-09-21T16:51:40Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO_DIEGO ALVES DO VALE.pdf: 1123185 bytes, checksum: 54612d838ec28b9e6b930c76d7018bb1 (MD5) / Made available in DSpace on 2017-09-21T16:51:40Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO_DIEGO ALVES DO VALE.pdf: 1123185 bytes, checksum: 54612d838ec28b9e6b930c76d7018bb1 (MD5) Previous issue date: 2017 / The fish industry generates wastes that negatively impact the environment. Providing solutions that minimize these impacts has become an interesting alternative in the last decades. Crab residues contain chitin in their chemical composition, which through the deacetylation process chitosan is obtained. One of the ways of using chitosan in the food industry is the formulation of films and edible coatings in order to prolong the shelf life of food products. The objective of this study was to produce films and edible coatings based on chitosan extracted from Uçá-crab (Ucides cordatus) for subsequent application on frozen Serra Spanish mackerel fillets (Scomberomorus brasiliensis). The films produced were characterized by water vapor permeability, solubility, color and opacity and mechanical properties. The antimicrobial activity of coating solutions was evaluated against four strains of psychotropic bacteria. The scattering coefficient served as a criterion in the choice of the best coating solution to be applied on frozen Serra Spanish mackerel fillets. Evaluations of fish quality parameters such as physico-chemical and microbiological analyzes as well as evaluation of fish, coating and glaze weight losses were carried out. The results showed that films containing 2.0% of chitosan (w/v) 0.6% of glycerol (v/v) presented good mechanical properties and protection against ultraviolet rays (darker films) without significantly altering the properties of opacity, water vapor permeability and solubility when compared to other chitosan and glycerol concentrations studied. Although all concentrations of chitosan coatings showed antimicrobial activity against the four strains of bacteria tested, the results showed that the lower the chitosan concentration the greater the antibacterial activity. The coating solution of 2.0% chitosan (w/v) and 0.6% of glycerol (v / v) was selected for application on frozen Serra Spanish mackerel fillets due to its good spreading coefficient. The chitosan coating presented lower weight loss than glaciation. Moreover, the chitosan coating presented better results in relation to the pH, nitrogen of the total volatile bases, reactive substances to thiobarbituric acid and antimicrobial activity. Therefore, the chitosan-based coatings presented potential as edible coatings, prolonging the shelf life of frozen Serra Spanish mackerel fillets (Scomberomorus brasiliensis). / A indústria de pescado gera resíduos que impactam de forma negativa o meio ambiente. Proporcionar soluções que miniminizem esses impactos vem se tornando uma alternativa interessante nas ultimas décadas. Os resíduos de caranguejos contém na sua composição química a quitina que através do processo de desacetilação obtem-se a quitosana. Uma das formas de utilizar a quitosana na indústria de alimentos é a formulação de filmes e revestimentos comestíveis com o intuito de prolongar a vida de prateleira dos produtos alimentícios. O estudo em questão teve como objetivo a produção de filmes e revestimentos comestíveis de quitosana extraída do caranguejo-uçá (Ucides cordatus) em diferentes concentrações de quitosana e glicerol para posterior aplicação em postas de serra (Scomberomorus brasiliensis) congeladas. Os filmes produzidos foram caracterizados quanto à permeabilidade ao vapor de água, solubilidade, cor e opacidade, tensão na ruptura e deformação na ruptura. Foram realizados testes das soluções filmogências para avaliar a atividadade antimicrobiana frente a cepas padrão de bactérias. O coefiente de espalhamento serviu como critério na escolha da solução de revestimento das postas do referido pescado. Foram feitas avaliações dos parâmetros de qualidade do pescado tais como análises físico-químicas e microbiológicas, bem como a avaliação da perda de peso do pescado, do revestimento e do glaze. Foi possível identificar que os filmes de quitosana de 2,0% (p/v) com 0,6% (v/v) glicerol apresentaram boas proriedades de alongamento, proteção contra raios ultravioleta (filmes mais escuro) sem alterar significativamente as propriedades de opacidade, de permeabilidade ao vapor de água e de solubilidade em relação às outras concentrações de filmes estudadas. Todas as concentrações dos revestimentos de quitosana apresentaram atividade antimicrobiana para quatros cepas-padrão de bactérias. Foi verificado que quanto menor a concentração de quitosana maior era a atividade antibacteriana. A solução de revestimento de quitosana a 2,0% (p/v) com 0,6% (v/v) de glicerol foi à escolhida para aplicação nas postas de serra devido ao seu bom coeficiente de espalhamento. O revestimento de quitosana sofreu uma menor perda em relação ao glaciamento. Também apresentou melhores resultados em relação aos valores de pH, nitrogênio das bases voláteis totais, reação as substâncias reativas ao ácido tiobarbitúrico e análise microbiológica. Diante do exposto pode-se verificar que os revestimentos a base de quitosana apresentaram potencial como revestimentos comestíveis, prolongando o tempo de prateleira de postas de serra (Scombemorus brasilienses) congelada.
5

The biology of and fishery for king mackerel, Scomberomorus commerson (Scombridae), along the southern Mozambique and KwaZulu-Natal coast.

Lee, Brendon. January 2013 (has links)
The king mackerel, Scomberomorus commerson, is an epipelagic, schooling predator supporting significant commercial, artisanal and recreational fisheries throughout the coastal waters of its Indo-Pacific distribution. Despite the importance of the species within the South West Indian Ocean, little research has been undertaken on its biology and fisheries on a regional basis over the past 20 years. The aim of this study was to evaluate the fishery and biology of S. commerson in the South West Indian Ocean and identify gaps in information required to ensure its effective management. Catch and effort data for the KwaZulu-Natal recreational S. commerson linefishery were extracted from the National Marine Linefish System in order to assess spatial and temporal trends in abundance. Generalized linear models utilizing the delta method were used to quantify the effect of year, month, region, rainfall and sea surface temperature on CPUE. Biological samples of S. commerson were collected monthly from within KwaZulu-Natal and southern Mozambique. Samples were analysed using standard biological techniques. A per-recruit analysis was conducted using the biological parameters from KwaZulu-Natal and southern Mozambique in order to assess the status of the S. commerson stock and provide management recommendations based on the findings. Long-term trends in CPUE were cyclic in nature with peaks and troughs appearing to be independent of fishing pressure. Seasonal abundance reflects the south-north migration into KwaZulu-Natal waters with short term environmental factors such as sea surface temperature significantly affecting spatial and temporal extent of the migration among regions. S. commerson spawn in southern Mozambique waters from September to January (spring-summer) with males maturing at a smaller size (65.2cm FL) compared to females (82.3cm FL). The overall sex ratio (M: F) was 1:1.36 possibly as a result of linefishing selecting for faster growing, larger females. S. commerson in KwaZulu- Natal and southern Mozambique display rapid growth over the first two years before slowing down considerably after maturity is reached. Females grow faster and live longer compared to males dominating the older and larger size classes, and attaining a maximum observed age of 14 years, although fish probably live up to 20 years. Natural mortality rate was estimated at 0.27 yearˉ¹. Fishing mortality for the combined region was 0.21 yearˉ¹. The per-recruit analyses for the KwaZulu-Natal and southern Mozambique indicated that the fishery is being optimally exploited with a current spawner biomass per recruit at 49% of its theoretical pristine level. Uncertainty with regards to the fishing pressure in southern Mozambique as a result of illegal fishing and fishing sectors targeting smaller S. commerson is a cause for concern. The current recreational daily bag limit of 10 fish.person.dayˉ¹ is considered excessive by many stakeholders. Given the similarity of the recreational ski-boat fishery in southern Mozambique, a reduction in the DBL of S. commerson to five fish pppd in both KwaZulu-Natal and southern Mozambique waters would benefit recreational fishers by more equitable sharing of the catch and potentially by reducing fishing mortality at times when the fish are aggregated and vulnerable to high catch rates. A reduced DBL limit would also reduce the incentive of individual anglers to make large catches and to sell their fish illegally. / M.Sc. University of KwaZulu-Natal, Durban 2013.
6

Linkages between environmental conditions and recreational king mackerel catch off west-central FLorida

Wall, Carrie C 01 June 2006 (has links)
The objective of this study was to determine if fronts sustained up to three days will result in an aggregation of kingfish due to the anticipated accumulation of forage, increasing fishing success at these locations. Automated algorithms to detect frontal features in satellite-derived sea surface temperature, chlorophyll concentration, water clarity, and fluorescence images were successfully adapted for the coastal waters off west-central Florida. The surface ocean fronts were used to study the linkages between environmental conditions and recreational catch statistics of king mackerel (Scomberomorus cavalla) during 19 seasonal tournaments held in April to May and October to November of 2004 and 2005. The local winds estimated from a USF Coastal Ocean Monitoring and Prediction System observing station were analyzed with the frontal data to examine factors that influence oceanic frontal formation and stability. The front detection algorithms were also applied to high-r esolution bathymetry data which serves as a new technique for analyzing bottom topography. The spatial relationships between catch data collected through 415 angler interviews, frontal boundaries and stability, bathymetric gradients, bottom structure, and baitfish presence were identified using ESRI ArcGIS.Fishing success and fishing effort were highly variable regarding the distance of fishing activity to the nearest front. This was attributed to non-persistent winds. Intermediate water clarity (0.7 to 1.0 mW cm-2 microm-1 sr-1), the presence of baitfish, and the side of the front with relatively less chlorophyll showed the greatest influence on the king mackerel catch rates. Fishing success was found to be significantly higher at fishing locations where baitfish were reported present compared to where they were not reported. Concurrent with the 2005 harmful algal bloom event, a significant decrease in king mackerel catch occurred in the fall of 2005 (208 fish) compared to fall 20 04 (818) and spring 2005 (538). Additionally, fishing locations with baitfish present were observed about 15% less often during the fall of 2005 than the preceding seasons. From this, a model can be developed to diagnose the environmental conditions that can be used by resource managers to better understand variations in catch, which result from naturally occurring phenomena or man-induced overfishing.
7

Age and growth of the Queen Mackerel (Scomberomorus plurilineatus) and Seventy-four (Polysteganus undulosus) of KwaZulu Natal, South Africa.

Chale-Matsau, Jacobeth R. January 1996 (has links)
This study provides information on the age and growth of two important Iinefish species, Scomberomorus pluriline~tus and Polysteganus undulosus. Age determination for both species was carried out using otoliths and growth was modelled using age- and length-based methods. For the age-based method various growth models were evaluated to determine which growth function best described the age-length data, whilst Shepherd's Length Composition Analysis was used to estimate growth parameters from length-frequency data. Preliminary stock assessments, based on limited catch data, were also attempted for both species. Age estimates for the pelagic migrant S. plurilineatus, derived from reading whole otoliths, ranged from 0 + to 6 + years. As validation by marginal increment analysis was inconclusive because of the seasonal occurrence of this species in KwaZulu-Natal waters, it was assumed that a single opaque band was laid down in the otolith annually. Reproducibility of age estimates evaluated using the average percentage error (APE) technique was good (9.4%). Von Bertalanffy growth parameters were poorly estimated from length-frequency data because multiple maxima were encountered on the fitting surface. However, from the age-length data, growth was adequately modelled by the von Bertalanffy growth equation: L t =9 3 5mmFL (l-e -0. 583yr-1 (t+o. 991yr) ) S. p!urilineatus are fully recruited to the fishery at the age of 1 + year and the ageiv at-50% maturity is 2 + years. Preliminary per-recruit analyses indicated that the spawner biomass of S. plurilineatus is at 50% of its unfished level. Polysteganus undulosus is an endemic, reef-dwelling sparid and large catches weremade earlier in the century. Age determination was carried out using sectioned otoliths collected in 1962 and 1963 before the collapse of the fishery. Age estimates ranged from 3 + to 20 + years. Marginal increment analysis indicated that active deposition of opaque bands occurred during winter but, because of the seasonal occurrence of P. undulosus in KwaZulu-Natal, validation was inconclusive. Reproducibility of the age estimates was low (APE = 18.2%) because of difficulties with band interpretation as a result of stacking on otolith margins in old fish. Von Bertalanffy growth parameters could not be adequately estimated from length frequency data because of the slow growth and longevity of this species. However, from the age-length data, no difference in growth rate between the sexes was observed, and growth for the combined sexes is described by the following logistic equation: L = 942mmTL t 1+e-O.277yr-l(t-S.178yrs) The age at full recruitment was found to be 12 + years and the age-at-50% maturity was 8.8 years. A preliminary stock assessment revealed that the spawner biomass of P. undulosus was already at 25% of its unfished level in the early 1960s. / Thesis (M.Sc.)-University of Natal, 1996.
8

Idade, crescimento e avaliação de estoque da serra Scomberomorus brasiliensis (Teleostei: Scombridae), na plataforma continental do Nordeste do Brasil

Francisco de Nóbrega, Marcelo January 2002 (has links)
Made available in DSpace on 2014-06-12T15:06:50Z (GMT). No. of bitstreams: 2 arquivo2003_1.pdf: 2833737 bytes, checksum: 0ee869bb95ebc93f78bf776b1fd02091 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2002 / A serra, Scomberomorus brasiliensis, representa um importante recurso pesqueiro no Nordeste do Brasil. A fim de analisar a estrutura etária das capturas da frota artesanal e o estado do estoque na região, foram amostrados entre 1998 e 2001 na Plataforma Continental do Nordeste 6148 exemplares da espécie. Essa atividade foi realizada no âmbito do Programa REVIZEE SCORE-NE. As amostragens foram realizadas em pontos de desembarques da pesca artesanal do Piauí à Bahia. Os exemplares foram identificados segundo o sexo e medidos. Os comprimentos variaram de 102 a 960 mm de comprimento zoológico. O comprimento zoológico médio de captura diminuiu de 1998 a 2001. Para o estudo de idade e crescimento, foram coletados 831 otólitos sagittae, de setembro de 1999 a abril de 2001. Relações entre as variáveis biométricas foram determinadas e apresentaram resultados significativos (ANOVA-P<0.01). Encontrou-se diferença significativa na proporção sexual, sendo 654 machos (59%) e 461 fêmeas (41%). A análise do incremento marginal nos otólitos indicou que as menores distâncias do último anel a borda ocorrem nos meses de novembro a março, marcando apenas um anel anualmente. Foram encontrados de 1 a 8 anéis, com comprimentos variando de 115 a 758 mm. Os seguintes parâmetros de crescimento foram obtidos pelo método direto: região Nordeste L&#8734; = 963,14 mm K = 0,15 ano-1 e t0 = -0,211 ano; costa leste L&#8734; = 845,74 K = 0,176 e t0 = -0,122; costa setentrional L&#8734; = 945,58 K = 0,164 e t0 = -0,061. Os parâmetros de crescimento estimados para sexos separados foram: L&#8734; =781,87 K=0,188 e t0 = -0,383 para os machos e L&#8734; = 1142,07; K=0,113 e t0 = -0,414 para as fêmeas. As curvas de crescimento foram comparadas pelo método de Kappenman (1981), e não apresentaram diferenças significativas (P > 0.05) por sexo e região. Para a avaliação de estoques foram utilizados os parâmetros de crescimento da amostra total da região Nordeste. Baseado na curva de captura foram obtidas as seguintes taxas de exploração: mortalidade total Z = 0,54; mortalidade natural M = 0,36; mortalidade por pesca F = 0,18 e taxa de exploração E = 0,33. Os modelos de rendimento por recruta (fio de navalha e seleção de ogivas) estimaram uma taxa de exploração máxima sustentável de E = 0,61 e E = 0,50, respectivamente. A análise de coortes baseada em idades forneceu uma biomassa de 5591 ton, para um rendimento de 1412 ton, explorando 25% do estoque anualmente. Projeções para exploração futura foram estimadas através do modelo de Thompson e Bell, utilizando taxas de mortalidades atuais, um valor médio de biomassa de 5603 ton para um rendimento de 1406 ton e valor de R$ 7.032.148 foram obtidos, explorando 25% do estoque anualmente. Os modelos utilizados sugeriram taxas de exploração (E) de 0,33 a 0,47, com explorações de 25% a 29% do estoque anualmente. Estes valores mostram que a espécie já se encontra próxima a seu limite máximo de exploração sustentável, com indícios de declínio da população. Medidas de manejo que visem o aumento do tamanho de captura se mostram necessárias a fim de promover a conservação desse importante recurso na região
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Bifenilas policloradas (PCBs) e pesticidas organoclorados em Scomberomorus cavalla: pescado de importância econômica na região metropolitana do Recife - PE

MIRANDA, Daniele de Almeida 26 August 2015 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-06-08T19:08:39Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Daniele Miranda (Dissertação) (1).pdf: 2212174 bytes, checksum: 072adb47d6f470af0ef00119e299bcf8 (MD5) / Made available in DSpace on 2016-06-08T19:08:39Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Daniele Miranda (Dissertação) (1).pdf: 2212174 bytes, checksum: 072adb47d6f470af0ef00119e299bcf8 (MD5) Previous issue date: 2015-08-26 / CNPQ / Poluentes orgânicos persistentes (POPs) são ubíquos no ambiente global devido a grande estabilidade química e ampla dispersão. As características lipofílicas destes compostos favorecem a sua acumulação em peixes. Tais compostos estão associados ao desenvolvimento de câncer e desregulação do sistema endócrino. Apesar das proibições e restrições atribuídas a estes compostos, eles são frequentemente detectados no ambiente e a população humana está exposta a esta classe de contaminantes, principalmente, através do consumo de alimentos contaminados, como o pescado. O presente estudo teve como objetivos: (1) implementar metodologia para análise de PCBs e pesticidas organoclorados (DDTs, HCHs, clordanos, heptacloro e mirex) em peixe; (2) verificar a ocorrência de tais compostos em Scomberomorus cavalla; (3) investigar possíveis correlações entre os níveis de contaminantes e os parâmetros biológicos da espécie (idade, sexo, estágio de maturação e percentual de lipídios); e (4) estimar a exposição da população humana local a PCBs e DDTs através do consumo S. cavalla. Amostras de músculo e fígado foram separadas de 20 peixes adquiridos em colônias de pesca de Recife e região metropolitana. O método de extração foi Soxhlet (8 h), seguido por purificação com tratamento ácido. O extrato final foi analisado através de cromatografia em fase gasosa acoplada a espectrometria de massas (GC-MS). A metodologia para análise de organoclorados foi implementada e avaliada através de material de referência certificado. O limite de quantificação do método foi em média 0,50 ng g-1 peso seco (ps). PCBs e DDTs foram os grupos de compostos detectados em maiores concentrações nos espécimes estudados. As concentrações de PCBs, DDTs e clordanos no músculo variaram de 2,88 a 97,4 ng g-1 ps, 0,92 a 11,6 ng g-1 ps e nd (não detectado) a 2,11 ng g-1 ps, respectivamente. No fígado as concentrações desses contaminantes variaram de 47,5 a 267 ng g-1 ps, 7,95 a 34,8 ng g-1 ps e nd a 5,52 ng g-1 ps, respectivamente. HCHs, heptacloro e mirex não foram detectados nas amostras. Os parâmetros biológicos de S. cavalla não apresentaram correlação com as concentrações dos compostos estudados. A estimativa de ingestão diária de PCBs e DDTs pela população pernambucana mostrou que a cavala é uma espécie segura para consumo, segundo limites de referência propostos por agências da Organização das Nações Unidas (ONU). / Persistent organic pollutants (POPs) are ubiquitous worldwide due to high chemical stability and long-range atmospheric transport. Their lipophilic properties facilitate accumulation in fish tissues. POPs have been associated with development of cancer and endocrine disruption in vertebrates. Despite the ban in most countries, they are still detected in the environment. Human populations are exposed to POPs mainly through consumption of contaminated food including fish. The aim of this study is four-fold: (1) to optimize a laboratory method for analyzing polychlorinated biphenyls (PCBs) and chlorinated pesticides (DDTs, HCHs, chlordane, heptachlor and mirex) in fish tissues; (2) to investigate the occurrence of chlorinated compounds in king mackerel (Scomberomorus cavalla); (3) to assess potential correlations between contaminant levels and biological parameters of king mackerel; and (4) to estimate exposure of local human populations to PCBs and DDTs through consumption of king mackerel. A total of 20 fishes were purchased from artisanal fishermen at Recife and metropolitan area, northeastern Brazil. Muscle and liver tissues were selected for analysis. Samples were Soxhlet-extracted for 8 h and cleaned up with concentrated sulfuric acid. The extracts were injected into a gas chromatography-mass spectrometry system (GC-MS). The laboratory method was validated with certified reference material. The average limit of quantitation was 0.50 ng g-1 dry weight (dw). PCBs and DDTs were the major contaminants found in the samples while HCHs, heptachlor and mirex were not detected. Concentrations of PCBs, DDTs and chlordane-related compounds in muscle ranged from 2.88 to 97.4 ng g-1 dw, 0.92 to 11.6 ng g-1 dw, and nd (not detected) to 2.11 ng g-1 dw, respectively. Concentrations of the same contaminants in liver ranged from 47.5 to 267 ng g-1 dw, 7.95 to 34.8 ng g-1 dw, and nd to 5.52 ng g-1 dw, respectively. Biological parameters of S. cavalla were not significantly correlated with contaminant levels. The local population estimated daily intake of PCBs and DDTs through fish consumption revealed that S. cavalla is a safe food. Such a conclusion is based on reference limits established by the United Nations (UN) specialized agencies.
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Desenvolvimento de alimento a base de pescado com teor reduzido de sal e qualidade sensorial para a alimentação escolar / Development of fish-based food with low salt content and sensory quality for school meals

Quadros, Diomar Augusto de, 1976- 30 August 2018 (has links)
Orientador: Helena Maria André Bolini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-30T23:02:50Z (GMT). No. of bitstreams: 1 Quadros_DiomarAugustode_D.pdf: 3437883 bytes, checksum: a4c528de83a60c6452013997d6642ced (MD5) Previous issue date: 2015 / Resumo: O presente trabalho teve como objetivo desenvolver um produto (hambúrguer) a base de pescado proveniente da pesca artesanal, com teor reduzido de sódio, como uma alternativa de oferta do produto à alimentação escolar. O estudo foi dividido em duas etapas: de campo e laboratorial. Na pesquisa de campo foi aplicado formulário de marcadores do consumo alimentar para indivíduos maiores de cinco anos, adaptado do Sistema de Vigilância Alimentar e Nutricional - Ministério da Saúde, como forma de avaliar o padrão alimentar dos estudantes de escolas públicas municipais de Matinhos/PR. Além do padrão alimentar, foi analisado o consumo de pescado e o hábito de consumo da alimentação escolar por meio de um questionário semiestruturado. Na fase laboratorial, foram determinadas as características biométricas, composição centesimal e os rendimentos da filetagem da Sororoca (Scomberomorus brasiliensis) e a composição centesimal, microbiológica e sensorial do produto elaborado (hambúrguer de Sororoca). Os resultados na fase de campo indicam que há um grande percentual de crianças que consomem salada crua (37,43%), frutas (49,70%), feijão (64,97%) e leite (79,94%) todos os dias, que são alimentos marcadores de alimentação saudável. Em relação aos alimentos marcadores de uma alimentação não saudável o consumo é elevado. Além disso, as crianças têm o hábito de consumo de peixe, preferencialmente frito, e da merenda escolar. Em relação ao produto elaborado, a redução de sódio não influencia os parâmetros físico-químicos, microbiológicos e sensoriais. Para o teste de aceitação, identificou-se que as formulações mais aceitas pelos consumidores adultos são as produzidas com polpa integral com 1,5% e 0,75% de sal. Entre os escolares todas as amostras foram bem aceitas e não foi identificado diferença entre elas. A ADQ® revelou que as amostras preparadas com polpa integral obtiveram uma intensidade maior para todos os atributos de aparência, aroma e sabor. Os termos descritores que direcionaram a preferência dos consumidores e determinam a aceitação das amostras são o formato de peixe, os gostos salgado e umami e os sabores de peixe, ervas e residual de tempero industrializado, sendo que o atributo formato do peixe influenciou positivamente os resultados. A redução no teor de sal proporcionou produtos com perfil sensorial dinâmico semelhante aos preparados com maior teor de sal, sem diferença significativa em tempo total de duração e com intensidade significativamente inferior (p < 0,05). Os resultados obtidos indicaram que é possível elaborar um produto para a alimentação escolar a base de pescado proveniente da pesca artesanal com redução de sal e com alta aceitação, promovendo a Segurança Alimentar e Nutricional dos estudantes / Abstract: This study aimed to develop a low-sodium product (burger)based on fish from artisanal fisheries as an alternative food in school meals. The study was divided into two stages: laboratory and field study. In the field study, food consumption markers for individuals over five years were used, which were adapted from the Food and Nutrition Surveillance System - Ministry of Health, in order to assess the dietary patterns of students from public schools in Matinhos / PR. In addition, fish consumption and the students¿ consumption habits were analyzed using a semi-structured questionnaire. In the laboratory study, the raw material (Scomberomorus brasiliensis) was evaluated for its physicochemical characteristics, while the processed product was characterized for its physicochemical, microbiological and sensorial properties. The results in the field study showed that despite a large percentage of children consumed raw salad, fruit, beans, and milk every day, a high rate of consumption of unhealthy foods was observed. In addition, it was observed that children have the habit of consuming fish and school meals. Regarding the processed product, sodium reduction did not affect the physicochemical, microbiological, and sensory parameters. For the acceptance testing, the formulations produced with the whole fish pulp and 1.5% and 0.75% salt were more accepted by adult consumers; among students, all samples were very well accepted, with no significant differences between them. The ADQ® revealed that the samples prepared with the whole pulp had higher intensities for all appearance attributes, aroma, and flavor. The descriptors that guided the consumers¿ preference and determined the product acceptance were fish format, salty and umami taste, fish flavor, herbs, and residual industrialized seasoning, and the attribute fish format positively affected the results. The lower salt content provided products with dynamic sensory profile similar to those prepared with higher salt, with no significant difference in total duration time, and with significantly lower intensity (p < 0.05). It is possible to develop a product for school meals based on fish from artisanal fisheries with reduced salt and high acceptance, therefore promoting food and nutrition security for the students / Doutorado / Consumo e Qualidade de Alimentos / Doutor em Alimentos e Nutrição

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