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The Impact of Culture on the Decision Making Process in RestaurantsBoonme, Kittipong 08 1900 (has links)
Understanding the process of consumers during key purchasing decision points is the margin between success and failure for any business. The cultural differences between the factors that affect consumers in their decision-making process is the motivation of this research. The purpose of this research is to extend the current body of knowledge about decision-making factors by developing and testing a new theoretical model to measure how culture may affect the attitudes and behaviors of consumers in restaurants. This study has its theoretical foundation in the theory of service quality, theory of planned behavior, and rational choice theory. To understand how culture affects the decision-making process and perceived satisfaction, it is necessary to analyze the relationships among the decision factors and attitudes. The findings of this study contribute by building theory and having practical implications for restaurant owners and managers. This study employs a mixed methodology of qualitative and quantitative research. More specifically, the methodologies employed include the development of a framework and testing of that framework via collection of data using semi-structured interviews and a survey instrument. Considering this framework, we test culture as a moderating relationship by using respondents’ birth country, parents’ birth country and ethnic identity. The results of this study conclude, in the restaurant context, culture significantly moderates consumers’ perception of service quality, overall satisfaction, and behavior intention.of OA.
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Avaliação da qualidade microbiológica de alimentos com a utilização de metodologias convencionais e do sistema simplate. / Utilization of conventional methodologies and simplate system for microbiological quality evaluation of foods.Silva, Maria Cecília da 04 July 2002 (has links)
Com a finalidade de se avaliar a correlação entre o sistema SimPlate e metodologias convencionais na análise microbiológica de alimentos, dezoito alimentos (nove de origem vegetal e nove de origem animal) foram analisados para contagem total de mesófilos aeróbios, bolores e leveduras e coliformes totais e fecais. Os resultados das análises microbiológicas foram comparados através do teste F, tendo havido diferença significativa (p<0,05) entre os métodos. As médias foram submetidas ao teste t-Student (p<0,05); para a contagem total de mesófilos aeróbios apenas em dois dos quinze alimentos considerados, maçã e beterraba, as metodologias convencional e SimPlate não diferiram entre si; para bolores e leveduras as metodologias não diferiram em quatro dos treze alimentos considerados, lingüiça, peixe, cheiro-verde e beterraba, e para coliformes totais, em seis dos doze alimentos considerados, carne suína, frango, lingüiça, leite cru, pêra e tomate. Uma análise de regressão dos dados mostrou boa correlação entre os dados obtidos para coliformes totais, pela metodologia dos tubos múltiplos e o SimPlate (0,88) e os dados de mesófilos aeróbios, obtidos pelo PCA e o SimPlate (0,80) e baixa correlação entre os dados obtidos na determinação de bolores e leveduras pelo BDA e o SimPlate (0,69). / In order to evaluate correlation among SimPlate system and conventional methods for food microbiological analysis, eighteen foods (nine from vegetable origin and nine from animal origin) were analyzed for mesophilic aerobic, yeasts and molds, total coliforms and fecal coliforms. Results of the three analysis were compared and significant differences (p<0,05) occurred among the majority of foods. For mesophilic aerobic counts, between the methodologies, PCA and SimPlate, difference were not significant in two of fifteen considered foods, apple and beetroot; for yeasts and molds, using acidify PDA and SimPlate, difference were not significant in four of thirteen considered foods, mixed sausage, fish, parsley and Welsh onion and beetroot; for total coliforms, using three-tube method and SimPlate, difference were not significant in six of twelve considered foods, raw pork, chicken, mixed sausage, raw milk, pear and tomato. Regression analysis of data showed correlation coefficients like, 0,88 for three-tube method and SimPlate; 0,80 between PCA and SimPlate and 0,69, between acidify PDA and SimPlate.
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Rastreabilidade de soja Roundup Ready® em produtos agrícolas e derivados: produção de materiais de referência e uso de marcadores AFLP / Roundup Ready® transgenic soybean traceability in agrifood products and derivatives: reference materials production and the use of AFLP markersAbrahão, Othon Silva 18 March 2008 (has links)
A introdução de variedades transgênicas de soja provocou grandes alterações no mercado mundial e na legislação de países produtores e compradores, principalmente no que se refere à certificação, rastreabilidade, biossegurança e rotulagem. A soja é responsável por quase metade das receitas com exportação do Brasil, estando presente na forma de matéria-prima ou ingrediente em parte significativa dos alimentos no mercado brasileiro. O limite estabelecido de 1,0 % para presença de transgênicos em alimentos, acima do qual a rotulagem passa a ser obrigatória, gerou a demanda por materiais de referência para controle e quantificação em matérias-primas e alimentos, para harmonização e uniformização dos resultados obtidos em diferentes equipamentos e laboratórios, atualmente produzidos com exclusividade pelo Instituto de Materiais de Referência e Medidas - IRMM, na Bélgica. Diante do alto custo e da dificuldade de obtenção destes produtos, foram elaborados, utilizando-se técnica de moagem e mistura criogênica, com verificação por PCR em tempo real, candidatos a materiais de referência para soja transgênica Roundup Ready® (soja RR) em pó nas concentrações de 0%, 0,1%, 0,5%, 1,0%, 2,0% e 5% de material transgênico. Para rastrear a origem da soja transgênica, aplicou-se o método de marcadores AFLP sobre 29 variedades de soja RR, sendo 21 argentinas e 8 brasileiras, encontrando-se 6 bandas polimórficas, produtos de 4 pares de primers, selecionados de um total de 67 reações usando diferentes combinações de primers seletivos. Por este método, foram caracterizadas 15 das variedades argentinas e todas as variedades brasileiras. Para alimentos processados em análise de PCR, adotou-se a estratégia de detecção de fragmentos curtos (cerca de 100 pb) de soja RR, com desenho de primers usando programas computacionais de livre acesso na Internet (Primer3, NetPrimer, Rebase) e validação por digestão com endonucleases e sequenciamento. Foram estabelecidos dois novos conjuntos de primers para detecção e quantificação de fragmentos dos genes da lectina e CP4 EPSPS de soja RR, testados nas 29 variedades de soja RR e três matrizes de alimentos à base de soja / The introduction of soybean transgenic cultivars brought several changes in both world trade and regulation rules for producers and consumers, mainly in relation to certification, traceability, biosafety and labeling. Soybean is one of the largest commodities in the world trade and responsible for half of the Brazilian export incomings, present as raw material or ingredient in significant part of foods in the local market. The adoption of the threshold of 1,0 % for nonintentional presence of GMO in food, requiring obligatory labeling for contents above this level, demands reference materials for the control and quantification of transgenics in raw material and processed food, allowing the harmonization of results from different methods and laboratories, currently being produced exclusively by the Institute for Reference Materials and Measurements - IRMM, in Belgium. Due to the high costs and difficulty to obtain these products, candidate reference materials of Roundup Ready® transgenic soybean (RR soybean) were produced at levels of 0 %, 0,1 %, 0,5 %, 1,0 %, 2,0 % and 5,0 % of transgenic material, using cryogenic milling and mixing techniques, with subsequent verification by real time PCR. Tracing of Roundup Ready cultivars by origin was done through AFLP molecular markers in a total of 29 RR soybean cultivars: 21 Argentinean and 8 Brazilian cultivars. Fingerprinting was possible in 15 Argentinean and all Brazilian cultivars through 6 bands obtained from 4 selective pairs of primers, singled out from 67 different combinations of selective primers. For PCR analysis of processed food, primers were designed using freeware sources over the Internet (Primer3, NetPrimer, Rebase) for short fragments amplification (around 100 bp). Primers sets for the amplification of lectin and CP4 EPSPS gene fragments from RR soybean were designed for the detection of these genes in the 29 RR soybean cultivars and three soybean based food matrices, with the results validated by endonucleases digestion and sequencing
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Detection and quantification of caffeine in the coffee industry using imprinted polymers and bare carbon electrodesRedivo, Luca January 2018 (has links)
Food quality control is a mandatory task in the food industry, and for coffee manufacturers, one of the key target compounds is caffeine, because of its well-known biological effects and currently expensive analytical methods are employed for caffeine quantification. This project was thought with the aim of developing a cost-effective caffeine sensor for application in industrial environments. Two main approaches were investigated: i) the use of imprinted polymers; ii) electrochemical using bare carbon electrodes. Chapter 1 is the main introduction, it focuses on the importance of food quality control, the limitation of the methodologies currently employed and it presents the advantages of using imprinted polymers recognition and electrochemistry signal transduction. Chapter 2 presents data related to studies of self-association of caffeine in water using a novel computational approach. The wider applicability of the method was assessed by studying self-association of paraxanthine and the results were validated via a collaboration with Miss R. Anastasiadi who employed isothermal titration calorimetry. Chapter 3 describes the synthesis of MIPs in water, starting with the selection of the functional monomers: HPTS (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt). The polymerisation conditions were optimised in terms of solvent to be used, initiator content, temperature and total monomer concentration. Afterwards, the polymers were synthesised, characterised, and preliminary data on the rebinding ability towards caffeine were presented. Chapter 4 focuses on electrochemical methods for the detection of caffeine using bare carbon electrodes. A voltammetric method for accurate determination of caffeine in beverages was developed. Based on the encouraging results obtained, further studies on the applicability of electrochemical methods for coffee quality analysis were done. A second method was developed for simultaneous detection of caffeine and polyphenols and an amperometric chemosensor for sucrose determination was acquired and its applicability for the analysis of green coffee beans was evaluated.
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Influência do genótipo, sexo e peso de abate na composição da carcaça e nas características de qualidade da carne suína. / Influence of genotype, sex and slaughter weight in the carcass composition and quality characteristics of pork meat.Angerami, Camila Nogueira 25 October 2004 (has links)
O experimento consistiu de dezesseis tratamentos distribuídos num esquema fatorial 4x2x2, sendo 4 genótipos (Excel (E) - Nn, Linha 21 (L21) - nn, Maximus (M) - NN e Optimus (O) - NN), 2 sexos (machos castrados e fêmeas) e 2 pesos (leves - 95 a 100Kg e pesados - 115 a 120Kg) e seis repetições. Foram realizadas medidas de composição da carcaça: Peso da Carcaça Resfriada (PCR), Área de Olho de Lombo (AOL), Comprimento de Olho de Lombo (COL), Profundidade de Toucinho (PT), Porcentagem de Carne Magra (%CM) e medidas de Espessuras de Músculo (EM) e Gordura (EG) e avaliações de qualidade de carne: pH, cor (L*a*b*), Perda por Exsudação (PE) e Capacidade de Retenção de Água (CRA). Os resultados estatísticos da composição da carcaça para o genótipo nn indicaram valor de AOL significativamente superior em relação aos genótipos Nn, NNM e NNO e valor de PT significativamente menor que NNM e NNO, porém, não diferindo de Nn. Quanto à EM, ocorreu uma tendência do NNM apresentar os maiores valores, seguido pelo Nn, nn e NNO. Em relação à EG, NNO mostrou os maiores valores, não diferindo significativamente de NNM e nn, enquanto o genótipo Nn apresentou o menor valor para esta característica. A %CM dos genótipos nn e Nn foi significativamente maior que NNM e NNO, confirmando a expressão do gene recessivo (n) em depositar mais carne na carcaça que o dominante (N). Os resultados estatísticos de qualidade de carne mostraram que o genótipo nn apresentou o menor valor de pH24 no músculo Semimembranosus, combinado com os maiores valores de luminosidade (L*) e PE em comparação com Nn, NNM e NNO. Não houve diferença significativa entre os genótipos NN and Nn na PE. Em relação à CRA, NNM obteve valor significativamente menor que Nn, nn e NNO. Os resultados obtidos permitem concluir que o gene halotano em homozigose (L21) contribuiu para a obtenção de uma carcaça mais musculosa, porém, com qualidade de carne inferior, apresentando maior incidência de carne PSE. Em relação ao sexo, os machos resultaram carcaças mais pesadas, mais gordas e carne com menor luminosidade. Finalmente, com exceção da %CM, os valores de composição da carcaça aumentaram com o peso de abate, não sendo constatadas mudanças nas características de qualidade avaliadas. / This experiment consisted of sixteen treatments in a 4x2x2 factorial arrangement, 4 genotypes (Excel - Nn, Line 21 - nn, Maximus - NN and Optimus - NN), 2 sexes (barrows and gilts) and 2 weights (light - 95-100Kg and heavy - 115-120Kg) and 6 repetition. The exams were submitted to the following carcass composition measurements: Cold Carcass Weight (CCW), Loin Eye Area (LEA), Loin Eye Length (LEL), Fat Depth (FD), Lean Meat Percentage (LM%) and Fat (FT) and Muscle (MT) Thickness. Meat quality measurements were also realized: pH, Color (L*a*b*), Drip Loss (DL) and Water Holding Capacity (WHC). The results of this study showed that genotype nn had shown significantly higher values of LEA than another genotypes and significantly lower values of FD than NNM and NNO, and it didnt differ from genotype Nn. There was a tendency by genotype NNM to show higher values of MT followed by Nn, nn and NNO. Genotype NNO showed higher values to FT and did not differed significantly from NNM and nn, while genotype Nn showed lower values to this characteristic. Genotypes nn and Nn showed significantly higher values of LM% than NNM and NNO. With reference to meat quality, genotype nn has shown lower value of pH24 measured in the muscle Semimenbranosus and higher values of L* and DL than genotypes Nn, NNM and NNO. Genotype NNM had significantly higher values of WHC than nn, Nn and NNO. There was no significant difference between NN and Nn when considered DL. The results above indicate that halothane gene in homozygous (nn) helped to obtain more muscular carcasses. On the other hand, this genotype showed worst meat quality. As a consequence of that, genotype nn has shown higher incidence of pale, soft and exudative meat. With reference to sex, barrows had significantly higher values to CCW, FD, FT, L* and b*, resulting paler meat and heavier and fatter carcass than gilts. Except for LM%, as carcass weight increased there were increases in all the characteristics. The data from this study suggest that there were no meat quality differences between the two slaughter weights.
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Avaliação da qualidade microbiológica de alimentos com a utilização de metodologias convencionais e do sistema simplate. / Utilization of conventional methodologies and simplate system for microbiological quality evaluation of foods.Maria Cecília da Silva 04 July 2002 (has links)
Com a finalidade de se avaliar a correlação entre o sistema SimPlate e metodologias convencionais na análise microbiológica de alimentos, dezoito alimentos (nove de origem vegetal e nove de origem animal) foram analisados para contagem total de mesófilos aeróbios, bolores e leveduras e coliformes totais e fecais. Os resultados das análises microbiológicas foram comparados através do teste F, tendo havido diferença significativa (p<0,05) entre os métodos. As médias foram submetidas ao teste t-Student (p<0,05); para a contagem total de mesófilos aeróbios apenas em dois dos quinze alimentos considerados, maçã e beterraba, as metodologias convencional e SimPlate não diferiram entre si; para bolores e leveduras as metodologias não diferiram em quatro dos treze alimentos considerados, lingüiça, peixe, cheiro-verde e beterraba, e para coliformes totais, em seis dos doze alimentos considerados, carne suína, frango, lingüiça, leite cru, pêra e tomate. Uma análise de regressão dos dados mostrou boa correlação entre os dados obtidos para coliformes totais, pela metodologia dos tubos múltiplos e o SimPlate (0,88) e os dados de mesófilos aeróbios, obtidos pelo PCA e o SimPlate (0,80) e baixa correlação entre os dados obtidos na determinação de bolores e leveduras pelo BDA e o SimPlate (0,69). / In order to evaluate correlation among SimPlate system and conventional methods for food microbiological analysis, eighteen foods (nine from vegetable origin and nine from animal origin) were analyzed for mesophilic aerobic, yeasts and molds, total coliforms and fecal coliforms. Results of the three analysis were compared and significant differences (p<0,05) occurred among the majority of foods. For mesophilic aerobic counts, between the methodologies, PCA and SimPlate, difference were not significant in two of fifteen considered foods, apple and beetroot; for yeasts and molds, using acidify PDA and SimPlate, difference were not significant in four of thirteen considered foods, mixed sausage, fish, parsley and Welsh onion and beetroot; for total coliforms, using three-tube method and SimPlate, difference were not significant in six of twelve considered foods, raw pork, chicken, mixed sausage, raw milk, pear and tomato. Regression analysis of data showed correlation coefficients like, 0,88 for three-tube method and SimPlate; 0,80 between PCA and SimPlate and 0,69, between acidify PDA and SimPlate.
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Étude de l'effet des radiations électromagnétiques pendant la congélation sur la structure de glace et la qualité des tissus des fruits et légumes / Study on the effect of electromagnetic radiations during freezing on ice structure and quality of fruit and vegetable tissuesJha, Piyush Kumar 09 November 2018 (has links)
L'objectif de cette étude était d'étudierl'effet d’un procédé innovant de congélation assistéepar micro-ondes (CAPMO) à faible énergie sur letemps de congélation, la qualité (microstructure,texture, perte de masse, et couleur) de la pomme etde la pomme de terre. La CAPMO des pommes etdes pommes de terre a été effectuée à unepuissance micro-onde constante (167 W/kg) et unepuissance micro-ondes appliquée par créneaux (500et 667 W/kg avec 10 s de micro-ondes sur unepériode de 30 s). Les températures ont été mesuréespendant le processus de congélation et lamicrostructure a été examinée en utilisant latomographie à rayons X et les techniques de cryo-SEM. D'autres paramètres de qualité tels que latexture, la perte de masse et la couleur ont étéévalués après décongélation de l'échantillon àtempérature ambiante.Les résultats ont montré que le processus deCAPMO n’affectait pas le temps de congélation.L'application de micro-ondes pendant le processusde congélation a produit une microstructure dequalité supérieure à celle de l'échantillon témoin ; LaCAPMO a réduit de manière significative la taillemoyenne des cristaux de glace dans les échantillonsde pommes et de pommes de terre. De plus, laCAPMO de la pomme et de la pomme de terre aentrainé une perte de masse moindre. La réductionde la fermeté / dureté et du module de Young aégalement été diminué par rapport à l'échantillontémoin. La couleur n'a pas été significativementinfluencée par la CAPMO. Parmi toutes lesconditions de congélation testées, la condition microondepulsée de 667 W/kg a donné le meilleur résultaten termes de réduction de la taille des cristaux deglace et de qualité. Ces résultats prometteursindiquent donc que l’application de micro-ondespendant la congélation permettrait d’obtenir desproduits congelés de meilleure qualité. / The objective of this study was toinvestigate the effect of innovative low energymicrowave assisted freezing (MAF) on freezing time,quality attributes (microstructure, texture, drip lossand colour) of apple and potato. MAF of apples andpotatoes was performed by applying constantmicrowave power (167 W/kg) and pulsed microwavepower (500 and 667 W/kg with 10 s pulse width and20 s pulse interval) during the freezing process. Thetemperature profile was monitored during thefreezing process, and the microstructure wasexamined using X-ray tomography and cryo-SEMtechniques. Other quality parameters such astexture, drip loss and colour were evaluated afterthawing frozen sample at room temperature.Results showed that the freezing time was notaffected by the MAF process. The application ofmicrowaves during freezing process producedsuperior microstructure than the control sample; MAFsignificantly reduced the mean ice crystal size inapple and potato sample. Moreover, MAF of appleand potato resulted in a lower drip loss, meanwhile,it also led to a lower reduction in firmness/hardnessand Young's modulus value if compared to controlsample. The colour was not significantly influencedby MAF. Among all the tested freezing conditions, the667 W/kg pulsed microwave condition yielded thebest result in terms of reduction in ice crystals sizeand retention of other quality parameters. Lastly,these results indicate that the application ofmicrowave during freezing would result in higherquality frozen products.
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Métodos de extração e qualidade da fração lipídica. / Extraction methods and quality of the lipid fraction.Brum, Aelson Aloir Santana 10 January 2005 (has links)
Um estudo crítico foi realizado utilizando quatro métodos clássicos de extração de lipídios em aveia em flocos e peito de frango. Foram comparados os rendimentos, o tempo de extração, a repetibilidade de cada método e a qualidade oxidativa da fração lipídica obtida. As metodologias utilizadas foram as de Soxhlet, com n-hexano como solvente, nos períodos de quatro e oito horas de extração; Folch et al., com clorofórmio e metanol na proporção de 2:1 (v/v); Bligh & Dyer, com clorofórmio, metanol e água na proporção de 1:2:0,8 (v/v) e Hara & Radin, com n-hexano e isopropanol, na proporção de 3:2 (v/v). Os resultados obtidos indicaram que para a aveia em flocos, os métodos de Soxhlet e Bligh & Dyer apresentaram um rendimento superior (7,71 % e 7,66 %, respectivamente) em relação ao método de Hara & Radin e Folch et al. (6,61 % e 6,93 %, respectivamente). No estudo do peito de frango, os métodos de Soxhlet, Folch et al. e Bligh & Dyer apresentaram um rendimento satisfatório de lipídios totais, sendo, respectivamente, de 1,56 %, 1,56 % e 1,65 %. Apesar do bom rendimento em lipídios totais, o método de Soxhlet afetou a qualidade da fração lipídica em ambas amostras, demonstrada pela presença de peróxidos (4,39 e 4,19 meq O2/kg no peito de frango; 3,71 e 3,70 meq O2/kg na aveia em flocos) e pela acidez oléica (2,58 % de ácidos graxos livres (AGL) no peito de frango; 2,25 e 2,24 % AGL na aveia em flocos), em ambos os períodos de tempo da extração. Com base nos resultados deste trabalho, indica-se a metodologia de Bligh & Dyer para os casos em que haja interesse em uso posterior das frações lipídicas, em detrimento da de Soxhlet, não recomendável para o fim mencionado. / A critical study was carried through with four clasical methods of extraction of lipids from chicken breast and oat flakes. The yield, the extraction time, the repeatability of each method and the oxidative quality of the lipid fraction were evaluated and compared. The methodologies evaluated were Soxhlet, with n-hexane as the solvent, in periods of four and eight hours of extraction; Folch et al., with chloroform and methanol in the ratio of 2:1 (v/v); Bligh & Dyer, with chloroform, water and methanol, in the ratio of 1:2:0.8 (v/v), and Hara & Radin, with n-hexane and isopropanol, in the ratio of 3:2 (v/v). The results indicated that for oat flakes, the methods Soxhlet and Bligh & Dyer presented higher yields in total lipids (7.71 % and 7.66 %, respectively) than the methods Hara & Radin and Folch et al. (6.61 % and 6.93 %, respectively). In the study with chicken breast, the methods Soxhlet, Folch et al. and Bligh & Dyer presented the highest yields, being respectively 1.56 %, 1.56 % and 1.65 %.Despite the good yields in total lipids, the Soxhlet method affected the quality of the lipid fraction in both samples, demonstrated by the presence of peroxides (4.39 and 4.19 meq O2/kg in chicken breast; 3.71 and 3.70 meq O2/kg in oat flakes) and by the acid values (2.58 % FFA [free fatty acids] in chicken breast for both extractions; 2.25 and 2.24 % FFA in oat flakes,) for both periods of time evaluated. Based on the results obtained in this research, the authors recommend Bligh & Dyer methodology whenever there is interest in further use of the lipid fraction and strongly disencourage Soxhlet method for the purpose mentioned.
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THE CONSUMPTION AND SALES PATTERN OF UGLY APPLES IN SOUTH KOREALee, Hyun Jong 01 January 2018 (has links)
Approximately half of all wasted food is fruits and vegetables. One major cause of food waste is abnormal aesthetics; even if it is just as delicious as its normal counterpart. Food with a non-standard appearance (hereafter called ugly food) can be expelled by the markets. To reduce such waste, ugly food campaigns, which were developed in Europe and spread throughout the world, advocate for the consumption of ugly food. To study the problem of ugly food waste, this thesis examines ugly apples, since apples are the most common, representative, and readily accessible fruit. The objective of this thesis is to suggest marketing strategies and actions to facilitate the consumption and sales of ugly apples that can be expanded to other ugly fruits and vegetables. The data used for analysis are obtained from the Rural Development Administration in Korea. The findings of the thesis indicate that younger people and lower-income households are more likely to purchase ugly apples from online markets, non-stores such as food trucks and traditional markets compared with mega-scale discount stores. When advertising ugly apples, food quality should be emphasized rather than price.
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Strong influences of larval diet history on subsequent post-settlement growth in the freshwater mollusc Dreissena polymorphaWacker, Alexander, Elert, Eric von January 2002 (has links)
Significant seasonal variation in size at settlement has been observed in newly settled larvae of Dreissena polymorpha in Lake Constance. Diet quality, which varies temporally and spatially in freshwater habitats, has been suggested as a significant factor influencing life history and development of freshwater
invertebrates. Accordingly, experiments were conducted with field-collected larvae to test the hypothesis that diet quality can determine planktonic larval growth rates, size at settlement and subsequent post-metamorphic growth
rates. Larvae were fed one of two diets or starved. One diet was composed of cyanobacterial cells which are deficient in polyunsaturated fatty acids (PUFAs), and the other was a mixed diet rich in PUFAs. Freshly metamorphosed animals from the starvation treatment had a carbon content per individual 70% lower than that of larvae fed the mixed diet. This apparent exhaustion of larval internal reserves resulted in a 50% reduction of the postmetamorphic growth rates. Growth was also reduced in animals previously fed the cyanobacterial diet.
Hence, low food quantity or low food quality during the larval stage of D. polymorpha lead to irreversible effects for postmetamorphic animals, and is related to inferior competitive abilities.
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