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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.
11

Diferenciação morfotípica de machos de camarão de água doce Macrobrachium amazonicum (Heller, 1862) (Crustacea, Decapoda, Palaemonidae) /

Moraes-Riodades, Patrícia Maria Contente. January 2002 (has links)
Orientador: Wagner Cotroni Valenti / Banca: Gilson Luiz Volpato / Banca: Julio Vicente Lombardi / Resumo: Esse trabalho teve como objetivo verificar a possível existência de morfotipos em machos de M. amazonicum e definir as características para a sua identificação. Animais provenientres de viveiros de cultivo de todas as classes de tamanho foram analisados quanto a cor e espinação do segundo quelípodo direito. A seguir, foram medidos para determinação dos comprimentos total, pós-orbital, da carapaça, do quelípodo direito e dos cinco artículos que o compõem. As relações entre essas dimensões foram determinadas, utilizando-se técnicas para estudos de crescimento relativo. O trabalho mostrou que a população de M. amazonicum é composta por quatro grupos distintos, que diferem na morfologia dos quelípodos e em várias relações morfométricas. Isto confirma a hipótese da existência de morfotipos nessa espécie. Pode-se, portanto definir quatro morfotipos, que foram chamados "Translucent Claw" (TC), "Cinnamon Claw" (CC), "Green Claw" (GC) e "Green Claw linha" (GC'). Os machos TC são pequenos, apresentam o quelípodo translúcido, geralmente sem espinhos, providos ou não de botões (espinhos em formação), ou com espinhos pequenos formando um ângulo £ 60º. O morfotipo CC é constituído por animais com tamanho similar a TC, com a coloração tendendo a cor de canela e espinhos do quelípodo formando ângulo £ 60º. Os machos GC constituem um grupo de animais de grande porte em relação a TC e CC, com quelípodos desenvolvidos e maiores que o comprimento pós-orbital. Estes apresentam coloração verdemusgo, com espinhos em inclinação variando entre 60º e 90º. Os camarões que constituem o morfotipo GC' apresentam características semelhantes ao grupo GC em cor e espinação, mas o comprimento do quelípodo é proporcionalmente menor, sendo inferior ao comprimento pósorbital. A identificação de cada casta de machos de M. amazonicum possibilitará o prosseguimento de... / Abstract: The aim of this paper was to investigate the morphotypic differentiation of Macrobrachium amazonicum male. A key for identification of these morphotypes was provided using observations on color and spination of chelipeds supplemented by relative growth techniques. Prawns were taken from nine earthen ponds at Jaboticabal, São Paulo, Brazil. Total length, post-orbital length and the length of carapace, chelipeds and all limb joints were measured on the right second pereiopod with a vernier caliper. Four distinct morphotypes were identified, "Translucent Claw" (TC), "Cinnamon Claw" (CC), "Green Claw" (GC) and "Green Claw apostrophe" (GC' ). They differ by chelipeds morphology and several morphometric relationships. TC prawns are small in size and present chelipeds translucent with tubercles or spines, which point distally at an angle £ 60º. CC males are similar to TC in size and spination, but present cinnamon chelipeds. GC and GC' are large prawns with long dark green chelipeds provided with long and robust spines, which point distally at an angle ranging between 60º and 90º. They differ only by chelipeds proportion. GC cheliped length overtake post-orbital length while the opposite occurs in GC' males. Recognition of morphotypes will be useful for future biology and culture works aiming increase pond production of M. amazonicum / Mestre
12

Behavioral factors influencing movement, dispersion and mortality in Macrobrachium rosenbergii

Peebles, John Bradbury January 1977 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1977. / Bibliography: leaves [210]-217. / Microfiche. / xvii, 217 leaves ill
13

Transport of lysine across the intestine of the freshwater prawn, Macrobrachium rosenbergii

Brick, Robert W January 1975 (has links)
Typescript. / Bibliography: leaves 117-126. / viii, 126 leaves ill
14

Environmental factors influencing adult sex ratio in guppies

McKellar, Ann E. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Biology. Title from title page of PDF (viewed 2008/12/07). Includes bibliographical references.
15

Análise da variabilidade genética e do padrão de atividade esterásica no hepatopâncreas de camarões palemonídeos expostos a diferentes pesticidas

Lima, Alexandre Vidotto Barboza [UNESP] 28 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-28Bitstream added on 2014-06-13T18:29:23Z : No. of bitstreams: 1 lima_avb_me_sjrp.pdf: 541849 bytes, checksum: dd314c2a6fc0feafdbd70701b0499531 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O gênero Macrobrachium Bate, 1868, pertence à família Palaemonidae, a qual é amplamente distribuída pelas regiões tropicais e subtropicais, apresentando grande importância nos ecossistemas que habitam. As esterases pertencem a um grupo de enzimas que hidrolisam, preferencialmente, os ésteres de ácidos carboxílicos. Diferentes tipos de esterases têm sido caracterizadas em inúmeros organismos, fato este que comprova sua importância fisiológica. Os organofosforados (OP) e carbamatos (CM) compõem um grupo importante de praguicidas que agem inibindo um vasto grupo de enzimas, dentre elas, as esterases. A avaliação da atividade de acetilcolinesterase (AChE) e carboxilesterase (CbE) tem sido empregada com sucesso para monitorar a presença destes praguicidas no ambiente. O presente trabalho teve como objetivo geral estudar a variabilidade genética de duas espécies pertencentes ao gênero Macrobrachium (M. jelskii e M. amazonicum), a partir da caracterização bioquímica das esterases do hepatopâncreas de machos e fêmeas adultos, e avaliar o comportamento das mesmas perante a exposição ao Diazinon e Clorpifos (OPs) e Carbaril (CM). No presente trabalho, esse sistema enzimático foi analisado nas duas espécies de camarões citadas acima. Foram visualizadas 12 bandas esterásicas em ambas as espécies, compreendendo quatro classes diferentes das mesmas (acetilesterase, arilesterase, carboxilesterase e colinesterase). Nenhuma diferença qualitativa na presença de bandas interespecíficas, e nem quanto ao sexo, essas diferenças existem apenas nas frequências das mesmas. Em M. amazonicum o diazinon inibiu parcialmente a AChEs, in vitro, e apresentou pequena inibição em CbE. Por outro lado este composto não atuou efetivamente em nenhuma das enzimas testadas em... / The genus Macrobrachium Bate, 1868, belongs to the Palaemonidae family, which is widely distributed throughout tropical and subtropical regions, with great importance in their habitat. Esterases belong to a group of enzymes which hydrolyze rather carboxylic acids esters. Different kind of esterases have been characterized in numerous organisms, this fact proves their physiologic importance. Organophosphate and carbamate compose an important group of pesticide which acts inhibiting a large group of enzymes, including esterases. The activity evaluation of acetylcholinesterase (AChE) and carboxilesterase (CbE) have been successfully employed to monitor this pesticides presence in environment. The present study has as general aim studying the genetic variability of two species from Macrobrachium genus (M. jelskii e M. amazonicum) from the esterases biochemistry characterization in hepatopancreas of adult male and female, and evaluates the behavior of these enzymes before the exposure to Diazinon and Clorpifos (OPs) and Carbaril (CM), important pesticides widely used in our region. In this work, this enzymatic system was analyzed in two prawns species mentioned above. Twelve esterasic bands were observed in both species, comprising four different classes of them (acetilesterase, arilesterase, carboxilesterase e colinesterase). No qualitative difference in the presence of interespecific bands, neither about the sexes was observed. These differences are only in their frequencies. In M. amazonicum, diazinon inhibited partially AChE and showed small inhibition of CbE. On the other hand this chemical did not operate in none of the enzymes tested for M. jelskii. Chlorpirifos induced a great inhibition as in AChE as in CbE to the tested species, but this inhibitory effect was... (Complete abstract click electronic access below)
16

Development of hatchery facilties for the breeding and larval rearing of selected Macrobrachium species

Cort, Myron Paul 23 April 2014 (has links)
M.Sc. / Please refer to full text to view abstract
17

Aspectos estruturais do hepatopâncreas, desenvolvimento ovocitário e caracterização hormonal de fêmeas de Macrobrachium amazonicum durante as fases de maturação gonadal /

Ribeiro, Karina January 2006 (has links)
Orientador: Irene Bastos Franceschini Vicentini / Banca: Antonio Marcos Orsi / Banca: Maíra Aparecida Stefanini / Banca: Margarida Maria Barros Ferreira Lima / Banca: Maria Terezinha Siqueira Bombonato / Resumo: O presente trabalho realizou o estudo dos aspectos estruturais do hepatopâncreas, ovários e da caracterização hormonal de fêmeas de Macrobrachium amazonicum, nos diferentes estágios de maturação gonadal. Para tanto utilizaram-se 150 fêmeas adultas subdivididas entre os cinco diferentes estágios de maturação ovariana. Após serem capturados os animais foram pesados e mortos por choque térmico. Ovários e hepatopâncreas foram coletados e pesados individualmente para obtenção dos índices gonadossomático (IGS) e hepatossomático (IHS). Para as análises de microscopia de luz e eletrônica de transmissão, ovários e hepatopâncreas foram fixados em solução de Karnovsky e seguiram os procedimentos de rotina de inclusão. Os ovários, hepatopâncreas e hemolinfa destinados à quantificação hormonal foram armazenados em ependorfes e preservados em nitrogênio líquido a -70ºC, para posterior processamento de radioimunoensaio visando avaliação das concentrações de estradiol, progesterona e testosterona. Os resultados relacionados ao IGS e IHS demonstram uma correlação inversa entre os ovários e o hepatopâncreas nos diferentes estágios de maturação gonadal. Em relação ao desenvolvimento ovariano, observa-se a distribuição de cinco tipos celulares ao longo dos cinco estágios de maturação gonadal. Desta forma encontram-se as ovogônias ou células germinativas mais jovens no estágio I de maturação ovariana. As células pré-vitelogênicas, observadas a partir do estágio II, apresentam vesículas de retículo endoplasmático rugoso. Essas vesículas são importantes nas fases de vitelogênese endógena e exógena. Os ovócitos em vitelogênese inicial, característicos do estágio III, apresentam a deposição de vitelo endógeno. As células em vitelogênese avançada, próprias do estágio IV de maturação gonadal, são o alvo principal da vitelogênese ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study described the structural aspects of the hepatopancreas and ovaries, and the hormonal features of females of the freshwater prawn Macrobrachium amazonicum, during the reproductive cycle. The specimens were captured and killed by thermic chock. The gonadosomatic (GSI) and hepatosomatic (HSI) indices were calculated as the percentage of the weight of the gonad and hepatopancreas to total body weight, respectively. Ovaries and hepatopancreas were fixed in Karnovsky solution and destined to light and ultrastructural microscopy studies. Small portions of the ovary, hepatopancreas and hemolymph were frozen in liquid nitrogen, for later steroid quantification (estradiol, progesterone and testosterone). The relationships between GSI and HSI demonstrate an inverse correlation between ovary and hepatopancreas during the maturation cycle. The oocytes distribution is variable depending on the ovarian maturation degree. The ovary in stage I consists of oogonia. The ovary in stage II consists mainly by previtellogenic oocytes that possess vesicles of the endoplasmic reticulum. These vesicles are important to endogenous and exogenous vitelogenesis. Initial vitellogenic oocytes are mainly observed in the ovary in stage III and possess vitelline reserve, called as endogenous vitelogenesis. Ovary in stage IV is composed of late vitellogenic oocytes that uptake exogenous vitellogenin. Mature oocytes present a corion formation. The hepatopancreas is composed by tubules that are lined by a pseudostratified epithelium, which consists of five cell types, identified as E (embryonic), F (fibrillar), B (blisterlike), R (resorptive) and M (basal). These cells present relationships with digestion and nutrient storage, which are very important for the reproductive processes ...(Complete abstract, click electronic access below) / Doutor
18

Análise da variabilidade genética e do padrão de atividade esterásica no hepatopâncreas de camarões palemonídeos expostos a diferentes pesticidas /

Lima, Alexandre Vidotto Barboza. January 2012 (has links)
Orientador: Lilian Castiglioni / Coorientador: Eduardo Alves de Almeida / Banca: Hermione Elly Melara de Campos Bicudo / Banca: Uderlei Doniseti Silveira Covizzi / Resumo: O gênero Macrobrachium Bate, 1868, pertence à família Palaemonidae, a qual é amplamente distribuída pelas regiões tropicais e subtropicais, apresentando grande importância nos ecossistemas que habitam. As esterases pertencem a um grupo de enzimas que hidrolisam, preferencialmente, os ésteres de ácidos carboxílicos. Diferentes tipos de esterases têm sido caracterizadas em inúmeros organismos, fato este que comprova sua importância fisiológica. Os organofosforados (OP) e carbamatos (CM) compõem um grupo importante de praguicidas que agem inibindo um vasto grupo de enzimas, dentre elas, as esterases. A avaliação da atividade de acetilcolinesterase (AChE) e carboxilesterase (CbE) tem sido empregada com sucesso para monitorar a presença destes praguicidas no ambiente. O presente trabalho teve como objetivo geral estudar a variabilidade genética de duas espécies pertencentes ao gênero Macrobrachium (M. jelskii e M. amazonicum), a partir da caracterização bioquímica das esterases do hepatopâncreas de machos e fêmeas adultos, e avaliar o comportamento das mesmas perante a exposição ao Diazinon e Clorpifos (OPs) e Carbaril (CM). No presente trabalho, esse sistema enzimático foi analisado nas duas espécies de camarões citadas acima. Foram visualizadas 12 bandas esterásicas em ambas as espécies, compreendendo quatro classes diferentes das mesmas (acetilesterase, arilesterase, carboxilesterase e colinesterase). Nenhuma diferença qualitativa na presença de bandas interespecíficas, e nem quanto ao sexo, essas diferenças existem apenas nas frequências das mesmas. Em M. amazonicum o diazinon inibiu parcialmente a AChEs, in vitro, e apresentou pequena inibição em CbE. Por outro lado este composto não atuou efetivamente em nenhuma das enzimas testadas em... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The genus Macrobrachium Bate, 1868, belongs to the Palaemonidae family, which is widely distributed throughout tropical and subtropical regions, with great importance in their habitat. Esterases belong to a group of enzymes which hydrolyze rather carboxylic acids esters. Different kind of esterases have been characterized in numerous organisms, this fact proves their physiologic importance. Organophosphate and carbamate compose an important group of pesticide which acts inhibiting a large group of enzymes, including esterases. The activity evaluation of acetylcholinesterase (AChE) and carboxilesterase (CbE) have been successfully employed to monitor this pesticides presence in environment. The present study has as general aim studying the genetic variability of two species from Macrobrachium genus (M. jelskii e M. amazonicum) from the esterases biochemistry characterization in hepatopancreas of adult male and female, and evaluates the behavior of these enzymes before the exposure to Diazinon and Clorpifos (OPs) and Carbaril (CM), important pesticides widely used in our region. In this work, this enzymatic system was analyzed in two prawns species mentioned above. Twelve esterasic bands were observed in both species, comprising four different classes of them (acetilesterase, arilesterase, carboxilesterase e colinesterase). No qualitative difference in the presence of interespecific bands, neither about the sexes was observed. These differences are only in their frequencies. In M. amazonicum, diazinon inhibited partially AChE and showed small inhibition of CbE. On the other hand this chemical did not operate in none of the enzymes tested for M. jelskii. Chlorpirifos induced a great inhibition as in AChE as in CbE to the tested species, but this inhibitory effect was... (Complete abstract click electronic access below) / Mestre
19

Estratégias de povoamento e despesca no cultivo do camarão-da-amazônia Macrobrachium amazonicum: efeitos na estrutura populacional e na produção

Preto, Bruno de Lima [UNESP] 03 August 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-03Bitstream added on 2014-06-13T20:48:49Z : No. of bitstreams: 1 preto_bl_me_jabo.pdf: 265627 bytes, checksum: 8fa1737e43e168a6e9afaf6b0685c04e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste trabalho foi verificar a influência do gradeamento e das despescas seletivas na estrutura populacional do Macrobrachium amazonicum. Doze viveiros de aproximadamente 0,01 ha foram estocados com 40 juvenis/m². O delineamento experimental foi em blocos casualizados com quatro tratamentos e três repetições. Os tratamentos foram: fração “upper” de juvenis gradeados, fração “lower” de juvenis gradeados, juvenis não gradeados mais uso de despescas seletivas e juvenis não gradeados (tradicional). As principais variáveis físicas e químicas da água foram monitoradas. Os camarões foram alimentados com dieta comercial peletizada (35% de proteína bruta). A biomassa dos camarões foi estimada por meio de biometrias realizadas a cada três semanas. Nestas, os camarões eram pesados e diagnosticados quanto ao sexo. Os machos foram classificados em “Translucent Claw”, “Cinnamon Claw”, “Green Claw 1” e “Green Claw 2”. As fêmeas foram classificadas em ovígeras, adultas não ovígeras e virgens. Estes parâmetros também foram estudados nas amostras dos camarões retirados nas despescas seletivas. Após 3,5 meses de cultivo foi realizada a despesca total. Os animais foram contados e uma amostra de 10 % de cada viveiro foi analisada quanto aos mesmos parâmetros das biometrias. O gradeamento dos juvenis e o uso das despescas seletivas alteram a estrutura populacional do M. amazonicum. A estrutura populacional no tratamento “lower” foi menos desenvolvida que no tratamento “upper”. Já a estrutura populacional no tratamento despesca seletiva foi alterada com a retirada dos animais dominantes ao longo do cultivo. / This work aimed to evaluate size-grading and selective harvesting effects on population structure of Macrobrachium amazonicum. Twelve 0.01 ha ponds were stocked with 40 juveniles/m². A randomized-complete-blocks design with 4 treatments and 3 replicates was used. The treatments were: upper size-graded juveniles, lower size14 graded juveniles, non-graded juveniles with selective harvesting and non-graded juveniles (traditional). The important water parameters for aquaculture were monitored. The animals were feed with a commercial pellet diet (35% crude protein). The prawn biomass was estimated throughout sample weighting every three week. After sex separation, the males were classified as “Translucent Claw”, “Cinnamon Claw”, “Green Claw 1” and “Green Claw 2”; and the females as barried, opened and virgins. That was also applied with the selective harvesting. After 3.5 months the ponds were completely harvested. The animals were counted and a 10% sample of each pond was weighted, sexed and classified. The size-grading juveniles and culled harvest changed the population structure of this specie. It was less developed in the lower size-graded compared to the upper size-graded treatment. The population structure in selective harvesting treatment was changed by the harvest of the dominant animals over the experimental period.
20

Efecto de la densidad de siembra y adición de substrato en el crecimiento y la supervivencia del "camarón gigante de Malasia " Macrobrachium rosenbergii en policultivo con "tilapia roja" Oreochromis niloticus

Maguiña Mendoza, Aryul Arturo January 2007 (has links)
En los últimos años se han desarrollados numerosas investigaciones con el fin de mejorar el cultivo del camarón gigante de Malasia, investigaciones en policultivo, siembra de juveniles graduados y la adición de substrato han dado muy buenos resultados. La mayoría de estas investigaciones han tenido como objetivos la maximización de los niveles de producción, obtener mejoras en los pesos finales e incrementar la resistencia a enfermedades. El objetivo del presente estudio fue evaluar el crecimiento y la supervivencia del camarón gigante de Malasia Macrobrachium rosenbergii con 2 densidades de siembra (D1 y D2) y 2 porcentajes de incremento de substratos (S1 y S2) en policultivo con Oreochromis niloticus tilapia roja. Para alcanzar este objetivo se utilizó un diseño factorial 2 x 2, es decir, se evaluaron 4 tratamientos, 2 niveles por cada uno de los 2 factores (D1S1, D1S2, D2S1 y D2S2), cada tratamiento con tres repeticiones. Los datos de talla, peso, supervivencia y biomasa, obtenidos de las biometrías fueron analizados utilizando el software estadístico Statgrapfhic v.7,0 analizado al 95% de confianza (α es menor que 0,05). Después de 80 días de cultivo se observó que el tratamiento T3 (D2S1) obtuvo los mejores crecimientos (7,05 ± 2,13 g) y los mejores porcentajes de supervivencia (97,5%) para el camarón gigante de malasia. Los dos niveles de adición de substrato fueron igualmente efectivos para el crecimiento del camarón, se encontró una relación inversa entre el incremento de los substratos y los porcentajes de supervivencia. El crecimiento en talla de la tilapia solo fue afectado por la interacción de los factores densidad y substrato donde los tratamientos T2 (D1S2) y T3 (D2S1) presentaron crecimientos significativamente mayores; el crecimiento en peso de la tilapia solo fue afectado por el factor substrato, encontrándose una relación directa; no se encontró diferencia significativa (p es menor que 0,05) para los porcentajes de supervivencia. Se encontró una relación directa entre el incremento de la densidad y la biomasa final del camarón gigante de Malasia, siendo el nivel D2 significativamente mayor que D1. El tratamiento T3 (690,1 Kg ha-1) presentó una biomasa significativamente mayor que T2 (420,9 Kg ha-1) y T1 (387,1 Kg ha-1), T3 y T4 no fueron significativamente diferentes (p es mayor que 0.05). Para la tilapia se encontró una relación directa entre en incremento del substrato y la biomasa final, siendo el nivel S2 significativamente mayor que S1. La biomasa del tratamiento T2 (629,7 Kg ha-1) fue significativamente mayor respecto a T1 (453,4 Kg ha-1). En el análisis de producción los tratamientos T2 y T3 alcanzaron los mejores valores, el análisis de proyección mostró que el policultivo camarón tilapia, con adición de substrato, es una buena alternativa para obtener mejores rendimientos y ganancias. / In recent years, several researches have been developed with the objective of improve the culture of the fresh water prawn Macrobrachium rosenbergii, for instance polyculture, size grading juveniles and adding artificial substrate to the ponds have achieve results, in addition the majority of those investigations in the fresh water prawn have had different objectives, such as increasing the productions levels, increasing the harvest weight and increasing the resistance of different illnesses. This study was designed to evaluate the growth and supervivence of the freshwater prawn Macrobrachium rosenbergii with 2 different densities (D1 y D2) and 2 percentages of added substrates (S1 y S2) in polyculture with Oreochromis niloticus “red tilapia”. In order to achieve this objective, the experiment was designed such as 2 x 2 factorial arrangement consisting in 4 treatment combinations with 2 levels for each of 2 factors (D1S1, D1S2, D2S1 y D2S2) and which 3 replicate for each treatment. The size, supervivence and total production obtained from biometries were analyzed using the software Statgrapfhic v.7,0 at 95 % confidence (α =0,05). After 80 days of culture, T3 (D2S1) treatment had the best weight (7,05 ± 2,13g) and percentage of supervivence (97,5%) to freshwater prawn, in addition the different levels of substrates had similar effect on the harvest weight of freshwater prawn, moreover an inverse relation was found between added substrate and percentage of supervivence. The body length of tilapia was only affected by density and substrate interaction, where T2 and T3 treatment had the best growth. The harvest weight of tilapia was only affected by the substrate and a direct relation was found between them. A significantly effect (p is less than0,05) was not found between the different percentages of supervivence. A direct relation was found between density and total production of the freshwater prawn, where D2 obtained better results than D1. T3 treatment (690,1 kg ha-1) had better yield than T2 (420,9 kg ha-1) and T1 (387,1 kg ha-1), T3 and T4 were not different. Tilapia had a direct relation between added substrate and total production, where S2 was significantly higher than S1. The production from T2 treatment (629,7 kg ha-1) was significantly higher than T1 (453,4 kg ha-1). The production analysis showed that polyculture of prawn-tilapia with added substrate, is a good alternative in order to obtain best productions and weights. / In recent years, several researches have been developed with the objective of improve the culture of the fresh water prawn Macrobrachium rosenbergii, for instance polyculture, size grading juveniles and adding artificial substrate to the ponds have achieve results, in addition the majority of those investigations in the fresh water prawn have had different objectives, such as increasing the productions levels, increasing the harvest weight and increasing the resistance of different illnesses. This study was designed to evaluate the growth and supervivence of the freshwater prawn Macrobrachium rosenbergii with 2 different densities (D1 y D2) and 2 percentages of added substrates (S1 y S2) in polyculture with Oreochromis niloticus “red tilapia”. In order to achieve this objective, the experiment was designed such as 2 x 2 factorial arrangement consisting in 4 treatment combinations with 2 levels for each of 2 factors (D1S1, D1S2, D2S1 y D2S2) and which 3 replicate for each treatment. The size, supervivence and total production obtained from biometries were analyzed using the software Statgrapfhic v.7,0 at 95 % confidence ( =0,05). After 80 days of culture, T3 (D2S1) treatment had the best weight (7,05 ± 2,13g) and percentage of supervivence (97,5%) to freshwater prawn, in addition the different levels of substrates had similar effect on the harvest weight of freshwater prawn, moreover an inverse relation was found between added substrate and percentage of supervivence. The body length of tilapia was only affected by density and substrate interaction, where T2 and T3 treatment had the best growth. The harvest weight of tilapia was only affected by the substrate and a direct relation was found between them. A significantly effect (p<0,05) was not found between the different percentages of supervivence. A direct relation was found between density and total production of the freshwater prawn, where D2 obtained better results than D1. T3 treatment (690,1 kg ha-1) had better yield than T2 (420,9 kg ha-1) and T1 (387,1 kg ha-1), T3 and T4 were not different. Tilapia had a direct relation between added substrate and total production, where S2 was significantly higher than S1. The production from T2 treatment (629,7 kg ha-1) was significantly higher than T1 (453,4 kg ha-1). The production analysis showed that polyculture of prawn-tilapia with added substrate, is a good alternative in order to obtain best productions and weights. / Tesis

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