The application of high pressure (HP) processing on trout and shrimps was investigated in order to study its effect on their quality attributes. Five levels of pressure, holding time and temperature were selected using a central composite rotatable design (CCRD), the central point being. 200 MPa, 30 min and 10°C. This design was used in order to permit the measurement and modeling of changes in various quality parameters as a result of changes in the process variables. The color parameters (L*, a*, and b* values), physical attributes (drip-loss, protein leaching and water holding capacity) and texture parameters (firmness and springiness) in each case were evaluated, and modeled as second order polynomial equations. / Artificial Neural Network modeling was employed to investigate its ability in predicting the quality changes in both pressure-treated trout fillets and shrimp samples, and its performance was with statistical models. / High pressure (HP) kinetics of the microbial destruction in both trout and shrimp was also studied. (Abstract shortened by UMI.)

The population of shrimps from five stations in the estuary and one station in Firth of Forth were sampled for two years from January 1992 to investigate their population dynamics, reproductive biology and feeding ecology. Sampling was carried out at high water and low water, six times a year, by towing an Agassiz trawl, with the Forth River Purification Boards' research vessel, the 'Forth Ranger'. Two residents, Crangon crangon and Pandalus montagui, and a migrant species, Crangon ailmanni, were identified as the main three species of shrimps in the estuary and Firth of Forth. C. crangon was found throughout the estuary while P. montagui was confined to the lower reaches of the estuary. C. alimanni appeared in the estuary in October and left by June. In the Firth of Forth, P. montagui and C. alimanni were the dominant species. The breeding cycle commenced in October, and berried females were found by December/January for all species. Berried females of P. montagui, and both male and female C. alimanni, migrated from the estuary to deeper areas, never to return. C. crangon females with eggs ready to hatch, spent females and larvae all occurred in the estuary. The larvae were present in the estuary from April to October. Larvae of the other two species were not found in the estuary. All species fed mainly on polychaetes, followed by bivalves and crustaceans, which indicated a benthophagous feeding habit. The choice of food depended on the local availability of prey items, and the range of the particular shrimp species within the area; shrimps fed on prey which was abundant in their area of residence rather than moving elsewhere. The Forth Estuary is well utilized by the three species with little competition between them. Although a slow growth rate was observed in C. crangon, the mean condition factor indicated that the conditions in the Forth estuary were close to those normally required for shrimps. The Forth estuary shelters three species of shrimps, with populations, varying between 1992 and 1993, of 1.6-7.7 x 107 for C. crangon, 1.6-2.5 x 107 for P. montagui and 0.7-1.0 x 107 for C. alimanni. These three species contributed to the total annual shrimp production, which ranged from 5.59-17.93 tons at low water in the ratio 40:14:1. Both resident and migratory fish species benefit from this production because shrimps play a key role in the food web, forming the major link between the lower benthic invertebrates and predatory fish.

Graduation date: 1961

Spoilage and the presence of pathogens, such as Listeria monocytogenes and Salmonella, are among the most common reasons for shrimp product detentions and recalls. In addition, both listeriosis and salmonellosis have been associated with the consumption of shrimp. For these reasons, there is interest in reducing Listeria and Salmonella contamination of shrimps. A review of literature indicated no detailed study that described the attachment of Listeria and Salmonella onto shrimps and their resulting persistence. In addition, information related to the control of these two pathogens on fresh shrimps is also limited. The work reported in this thesis aims to partially fill these gaps. These aims were met through four studies. In the first study, the initial attachment and colonization of Listeria and Salmonella onto fresh and cooked shrimp carapaces and tissue was examined. The chitinolytic activity and the physicochemical properties namely cellular surface charge (CSC), hydrophobicity and electron donor/acceptor potential were also determined for all the strains. CSC was determined using zeta potential measurements. Hydrophobicity was determined using three hydrophobicity determination methods, while microbial adhesion to solvents was used to determine the electron donor/acceptor potential. Attachment and colonization of Listeria and Salmonella were demonstrated. Abdominal carapaces showed higher levels of bacterial attachment (p<0.05) than head carapaces while Listeria consistently exhibited greater attachment (p<0.05) than Salmonella on all surfaces. Chitinase activity of all strains was tested and found not to occur at the three temperatures (10°, 25° and 37°C) tested. Salmonella had significantly (p<0.05) more positive CSC than Listeria. A significant difference (p<0.05) in surface roughness between abdominal and head carapaces was noted. From the results obtained, it is possible to conclude that certain bacterial physicochemical properties and carapace roughness were involved in the attachment to carapaces but not attachment to tissue or colonization to carapace and tissue. The influence of attachment and colonization of Listeria and Salmonella onto shrimp surfaces on the resistance against environmental stress was investigated in the second study. Planktonic, attached and colonized cells of Listeria and Salmonella were challenged with high (50°, 60° and 70°C) and low (4°C) temperature, 100 ppm sodium hypochlorite solution, and acetic, hydrochloric and lactic acids (pH 4.0). Attached and colonized Listeria and Salmonella showed significantly greater (p<0.05) resistance to heat (~1.3-2.6 fold increase in D-values), hypochlorite (~6.6->40.0 fold) and acids (~4.0-9.0 fold) than their planktonic counterparts. There were no significant differences (p>0.05) in the survival of planktonic, attached or colonized cells of Listeria and Salmonella stored under refrigerated conditions. The increase in resistance observed in attached and colonized cells could have an important implication for shrimp product’s safety in general. In the third study, bilimbi (Averrhoa bilimbi L.) and tamarind (Tamarindus indica L.) juices were used to reduce Listeria monocytogenes Scott A and Salmonella Typhimurium ATCC 14028 populations on raw shrimps after washing and during storage (4ºC). The uninoculated raw shrimps and those inoculated with L. monocytogenes Scott A and S. Typhimurium ATCC 14028 were washed (dipped or rubbed) in sterile distilled water (SDW) (control), bilimbi or tamarind juice. Naturally occurring aerobic bacteria (APC), L. monocytogenes Scott A and S. Typhimurium ATCC 14028 counts of washed shrimps were determined on days 0, 3 and 7 of storage. Compared to SDW, bilimbi and tamarind juice significantly (p<0.05) reduced APC, L. monocytogenes Scott A and S. Typhimurium ATCC 14028 numbers on day 0. There was a significant difference (p<0.05) in bacterial reduction between the dipping and rubbing methods. Regardless of washing treatments or methods, populations of S. Typhimurium ATCC 14028 decreased slightly while populations of L. monocytogenes Scott A and APC increased significantly during refrigerated storage. These results suggest that consumable household items could be adopted as a natural method of decontaminating shrimps just before preparation and consumption. In the final study, use of nisin alone and in combinations with EDTA and salts of organic acids (potassium sorbate, sodium benzoate, or sodium diacetate) to control L. monocytogenes, Salmonella and native microflora on fresh shrimps were evaluated. Uninoculated, and Listeria monocytogenes or Salmonella inoculated, shrimps were dipped in treatment solutions, vacuum packaged and stored at 4ºC for 7 days. Listeria monocytogenes, Salmonella and native microflora counts were determined on days 0, 3 and 7. Nisin-EDTA-potassium sorbate and nisin-EDTA-sodium diacetate significantly reduced (p<0.05) L. monocytogenes numbers by 0.94-1.20 and 1.07-1.29 log CFU/g respectively, as compared to the control. All treatments failed to reduce (p>0.05) Salmonella counts on shrimps. At the end of storage, the native microflora counts on all nisin-EDTA-organic acids salts treated shrimps were significantly lower (p<0.05) than the control. The results suggest that some of the treatments can be used to improve shrimp microbial safety and shelf-life. Through achieving the aforementioned aims the present thesis was able to enhance the knowledge and literature available concerning the initial attachment of Listeria and Salmonella on shrimps, their persistence as well as methods to control them

Theses (M.S.)--University of New Hampshire (Dept. of Zoology), 2008. / Includes bibliographical references. Also available online.

Orientador: Antonio Leão Castilho / Resumo: Inventários de fauna são essenciais para a descrição da biota de qualquer localidade. O presente estudo teve como objetivo investigar a composição faunística e a estrutura da comunidade de camarões carídeos associados ao substrato consolidado nas regiões de duas ilhas do estado de São Paulo. Os locais selecionados para coleta dos indivíduos foram esclhidos a fim de elucidar a pouca informação que é fornecida atualmente sobre essa comunidade bentônica em áreas de proteção ambiental, como os Parques Marinhos Laje de Santos e Ilha da Vitória, o que dificulta a criação de protocolos de manejo e conservação das áreas. Foram realizadas expedições para coleta dos indivíduos no período de junho/15 e junho/16, utilizando técnicas de busca ativa por meio de mergulho autônomo e instalação de Substratos de refúgio artificial no sublitoral rochoso. Em laboratório, todas as espécies foram idenficiadas e registradas quanto ao sexo. O total de 323 indivíduos foi amostrado nas duas regiões, com 13 espécies compondo a fauna de camarões carídeos na Ilha da Vitória, distribuídas em quatro famílias e seis gêneros. Para a Laje de Santos foram identificadas 12 espécies de três famílias e cinco gêneros. Do total de 17 espécies registradas, com estrutura da comunidade semelhante para Laje de Santos e Ilha da Vitória, a família Alpheidae foi a mais representativa, com 12 espécies registradas, seguida de Palaemonidae com três espécies. Alpheus formosus e Cuapetes americanus foram as espécies dominante... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Made available in DSpace on 2016-09-27T13:40:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-26. Added 1 bitstream(s) on 2016-09-27T13:45:21Z : No. of bitstreams: 1 000868505.pdf: 2803363 bytes, checksum: 5290989525d2aa94b7ae30873ee5dc96 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O camarão Exhippolysmata oplophoroides é uma espécie bastante comum no sudeste brasileiro, não possui interesse comercial sendo capturada como fauna acompanhante. O objetivo do estudo e caracterizar a distribuição ecológica e estimar a fecundidade e o investimento reprodutivo de E. oplophoroides no litoral sudeste brasileiro. Os indivíduos coletados nas regiões de Ubatuba e Caraguatatuba no período de julho de 2001 a junho de 2003, foram utilizados para estudar a distribuição ecológica, enquanto os indivíduos coletados em Ubatuba em julho de 2011 foram utilizados para estimar a fecundidade e investimento reprodutivo. As coletas utilizando um barco camaroneiro, equipado com redes de arrasto do tipo double-rig. O comprimento do cefalotórax (CC) dos camarões foi mensurado sob estereomicroscópio ópitico. Na análise de fecundidade e investimento os indivíduos tiveram o (CC) mensurado utilizando paquímetro de precisão 0.01 mm e agrupados clases de tamanho. A massa de ovos foi classificada de acordo com o seu estágio de desenvolvimento. Foram coletados 4059 indivíduos. A região de Ubatuba apresentou uma abundância maior do que a região de Caraguatatuba, embora não tenha diferido estatisticamente (p=0.1148). Os pontos mais abundantes foram os de 5 e 20 metros (p=0.0255). A maior abundância foi de camarões na fase FHO, seguido por FHNO e FM, respectivamente. Em relação ao (CC), não observou-se diferença entre os tamanhos para os três grupos demográfico (p= 0.1733). O grupo FM ficou restrito apenas às quatro primeiras classes de tamanho (3.5 a 7.0mm), indicando que a medida que o animal cresce ele passa a ser (HPS). No estudo de fecundidade e investimento reprodutivo foram analisadas um total de 116 individuos, que variaram 9.4 mm a 13.8 mm de CC. O tamanho médio dos indivíduos da população foi de 11.77 ± 0.99 mm de CC. Os resultados da regressão linear simples indicaram uma relação significativa entre o... / The shrimp Exhippolysmata oplophoroides is a common species in the Southeast of Brazil, with no business interest and it is part of by-catch. The objective of this study is to characterize the ecological distribution and estimate the fecundity and the reproductive investment of E. oplophoroides in the southeast Brazilian coast. Individuals collected in the regions of Ubatuba and Caraguatatuba from July 2001 to June 2003 were used to study the ecological distribution, while individuals collected in Ubatuba in July 2011 were used to estimate fecundity and the reproductive investment. The samplings were carried out with an appropriated boat, equipped with double-rig trawls net. The length of the cephalothorax (CC) of the shrimp was measured under optic stereomicroscope. For the analysis of fecundity and investment, the CC of the individuals was measured using a Vernier caliper accuracy of 0.01 mm and grouped in size classes. The mass of the eggs was classified according to their development stage. A total of 4,059 individuals were collected. The Ubatuba region presented greater abundance than the region of Caraguatatuba, although it differed statistically (p = 0.1148). The most abundant were those of 5 and 20 meters (p = 0.0255). The highest abundance was of shrimp on FHO phase, followed by FHNO and FM, respectively. In relation to CC, no difference was observed between the sizes for the three demographic groups (p = 0.1733). The FM group was restricted to only the first four size classes (3.5 to 7.0 mm), indicating that as the individual grows it becomes (HPS). In the study of fecundity and reproductive investment a total of 116 individuals was analyzed, which ranged from 9.4 mm to 13.8 mm of CC. The average size of the individuals of the population was 11.77 ± 0.99 mm of CC. The results of simple linear regression showed a significant relationship between the length of the carapace and the number of eggs, for individuals with end-stage...

Made available in DSpace on 2016-09-27T13:40:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-08-29. Added 1 bitstream(s) on 2016-09-27T13:45:22Z : No. of bitstreams: 1 000215426.pdf: 678537 bytes, checksum: dd3f6c1764398162abe96aecc6f4743b (MD5) / O camarão Macrobrachium amazonicum tem sido explorado comercialmente através da pesca artesanal na América do Sul. Devido ao seu grande potencial na aqüicultura, um programa multidisciplinar foi estabelecido recentemente, visando à obtenção de tecnologia para a produção. Enfatizando os processos reprodutivos, detalhes estruturais do sistema reprodutivo em camarões de água doce ainda não foram totalmente elucidados e com isso, dificultam quaisquer tentativas para controle do processo reprodutivo. Deste modo, este trabalho tem como objetivo caracterizar o sistema reprodutivo de machos de M. amazonicum, de acordo com os quatro morfotipos já descritos para esta espécie. Estes quatro morfotipos foram estabelecidos de acordo com a coloração, forma e espinação do segundo par de pereiópodos (quela), comprimento dos própodos e da carapaça, e são denominados: Transluscent Claw (TC), Cinnamon Claw (CC), Green Claw' (GC ') e Green Claw (GC). Os índices Gonadossomático (IGS) e Hepatossomático (IHS) foram determinados para 10 machos de cada morfotipo, que foram caracterizados pelas características externas. O sistema reprodutor foi retirado, fixado e processado em rotina histológica. A análise estatística (SAS) mostrou os seguintes resultados (p < 0.05): CC < (TC = GC ' = GC) para IGS; e TC < (GC ' = GC) para IHS. As análises histológicas entre os quatro morfotipos evidenciaram as mesmas características morfológicas para os morfotipos GC' e GC. Baseados nestes resultados sugere-se apenas só três morfotipos para o camarão de água doce M. amazonicum: TC, CC e GC / Macrobrachium amazonicum has been exploited by artisan fisheries in South America. Because of its great aquaculture potential, a recent multidisciplinary program was established to improve farming techniques. Despite this and the emphasis on reproductive processes, structural details on prawn reproductive system are still not well understood and make difficult any attempt to control its reproduction. Thus, this study attempted to characterize the reproductive system of M. amazonicum males according to the four developmental morphotypes described in other Macrobrachium species. These four morphotypes are established according to coloration, second pereiopod (claw) shape and spination, and propodus and carapace lengths, and are named: Translucent Claw (TC), Cinnamon Claw (CC), Green Claw' (GC') and Green Claw (GC). The gonadosomatic (GSI) and hepatosomatic (HSI) indices were determined for 10 prawns in each morphotype, which were unequivocally characterized by these traits. Their testes were then fixed for histological routine. Statistical analyses (SAS) showed the following results (p < 0.05): CC < (TC = GC' = GC) for GSI; and TC < (GC' = GC) for HSI. Histological analyses among the four morphotypes showed the same morphological characteristics for GC' and GC. Based on these results we suggest only three morphotypes for the freshwater prawn M. amazonicum: TC, CC and GC

Made available in DSpace on 2016-09-27T13:40:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-14. Added 1 bitstream(s) on 2016-09-27T13:45:35Z : No. of bitstreams: 1 000330173.pdf: 377788 bytes, checksum: 6b7569c1ae257dbcf813728f816468d7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os objetivos da presente tese foram determinar a salinidade mínima na qual larvas de Macrobrachium. amazonicum não alimentadas sobrevivem e se desenvolvem, determinar a intensidade luminosa adequada ao desenvolvimento larval, investigar a incidência alimentar no tubo digestivo de larvas em relação a náuplios de Artemia e dieta inerte, bem como o estágio no qual se inicia a ingestão de alimento exógeno e avaliar o efeito de regimes alimentares no desenvolvimento, na incidência alimentar no tubo digestivo, na sobrevivência, na produtividade e no crescimento na larvicultura dessa espécie. Os dados demonstraram que as larvas da população estudada dessa espécie não sobrevivem em água doce. No entanto, completam seu desenvolvimento larval em salinidades baixas de até 1‰. A luminosidade 7,8±2,5 μmol.s-1.m-2 (aproximadamente 390±125 lux) melhora o desempenho das larvas de M. amazonicum em termos de desenvolvimento larval, produtividade e ganho de peso. As larvas dessa espécie a partir de zoea II começam a se alimentar de náuplios de Artemia. As larvas para se desenvolverem precisam se alimentar de náuplios de Artemia do estágio II ao IV. As larvas dessa espécie no estágio III preferem náuplios de Artemia, mas ingerem dieta inerte muito bem se este for o único alimento disponível. A substituição total de náuplios de Artemia por dieta inerte a partir de zoea V não afeta negativamente o desenvolvimento larval dessa espécie / The present thesis studied Macrobrachium amazonicum larvae for determining: 1) the minimal salinity required for the survival and development of feed deprived larvae; 2) the best light intensity suitable for larval development; 3) the digestive tract content (Artemia nauplii and/or inert food) and the larval stage at the beginning of exogenous food ingestion; and 4) the effect of feeding regimes on the development, digestive tract content, survival, productivity and growth. The results showed that these larvae do not survive in freshwater, but the development can be completed in low salinity (1‰). Mean light intensity of 7.8±2.5 μmol.s-1.m-2 (about 390±125 lux) improves M. amazonicum larval development, productivity and weight gain. Moreover, larvae at Zoea II stage start feeding on Artemia nauplii and this live food is required until zoea IV. Zoea III larvae prefer Artemia nauplii, but accept inert food when it is the only available food. Total substitution of inert diet in place of Artemia nauplii from zoea V stage does not affect M. amazonicum larval development

Made available in DSpace on 2016-09-27T13:40:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2005. Added 1 bitstream(s) on 2016-09-27T13:45:45Z : No. of bitstreams: 1 000330405.pdf: 425483 bytes, checksum: 44676169fd379e6cbe11048b67c63fa7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os viveiros de cultivo semi-intensivo de camarões de água doce são ecossistemas límnicos em fase inicial de sucessão ecológica. Neste trabalho, foi realizado um estudo limnológico de viveiros de cultivo de Macrobrachium amazonicum submetidos a diferentes taxas de arraçoamento e tipos de despescas, visando fornecer subsídios para o entendimento desses ecossistemas e o estabelecimento de um manejo adequado. Doze viveiros com cerca de 0,01 ha foram povoados com 20 juvenis de M. amazonicum.m-2. Os animais foram alimentados com ração extrusada na proporção de 6 a 9% da biomassa até a 14. a semana. Então, os camarões contidos em cada três viveiros foram arraçoados com 3%, 5% e 7% da biomassa dos camarões. Outros três viveiros foram submetidos à despesca mista. Semanalmente, foram determinadas as seguintes variáveis da água: temperatura, oxigênio dissolvido, demanda bioquímica de oxigênio, pH, alcalinidade total, condutividade elétrica, nitrato, nitrito, nitrogênio amoniacal, nitrogênio total, ortofosfato solúvel, fósforo total, clorofila a, clorofila b, clorofila c, feofitina, turbidez e sólidos totais suspensos. Após 145 dias, realizou-se a despesca total em todos os viveiros. Não foi observado nenhum padrão de variação temporal das variáveis limnológicas ao longo do cultivo. Estas foram mais dependentes dos processos biológicos que ocorreram no interior dos viveiros do que da água de renovação. A ração diária teve pouco efeito sobre a qualidade da água dos viveiros do que da água de renovação. A ração diária teve pouco efeito sobre a qualidade da água dos viveiros, efluentes e nenhuma sobre os depósitos de carbono, nitrogênio e fósforo no fundo. De um modo geral, as variáveis limnológicas apresentaram baixa correlação entre si. Possivelmente, as características intrínsecas de cada viveiro tiveram maior efeito sobre a qualidade da água do que... / Grow-out ponds are ecosystems at the first stages of ecological succession. In this research, a limnological study on grow-out ponds of Macrobrachium amazonicum subjected to different feed levels and harvest management was performed. Twelve 0.01 ha earthen ponds were stocked with 20 juveniles.m-2. Prawns fed commercial diet at a rate of 7 to 9% of biomass until 14a. week. Then, each three ponds were fed with 3%, 5% and 7% of prawn biomass. Three other ponds were subjected to selective harvest. After 145 days of stocking, all ponds were drained and harvested. The following water parameters were weekly determined: temperature, dissolved oxygen, oxygen biochemical demand, pH, total alkalinity, electrical conductivity, nitrate-N, nitrite-N, ammonia-N, total nitrogen, soluble orthophosphate, total phosphate, chlorophyll a, chlorophyll b, chlorophyll c, pheophytin, suspended total solids and turbidity. Limnological parameters did not show any temporal pattern. Exchange water and daily feeding slightly affected water quality and effluents. Carbon and nitrogen did not accumulated in water column or soil while phosphate was immobilized or trapped by the mud. Feeding rate and kind of harvest showed low effect on water quality, effluents and none on accumulation of carbon, nitrogen and phosphorus, in the mud. Correlation among water quality parameters are weak or absent. Data suggest that intrinsic characteristics of each pond play a major role on pond ecology