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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.
71

Desempenho reprodutivo do camar?o-rosa Farfantepenaeus brasiliensis (Latreille, 1817) (Crustacea, Decapoda, Penaeidae) em cativeiro: Efeito da alimenta??o e propor??o sexual. / Reproductive performance of the pink shrimp Farfantepenaeus brasiliensis (Latreille, 1817) (Crustacea, Decapoda, Penaeidae) raised in captivity: Effect of diets and sex ratio.

Flor, Helaine dos Reis 01 September 2009 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-07-24T16:03:54Z No. of bitstreams: 1 2009 - Helaine dos Reis Flor.pdf: 3447034 bytes, checksum: 3861cf7664eb46a21add49a26a4479c2 (MD5) / Made available in DSpace on 2017-07-24T16:03:54Z (GMT). No. of bitstreams: 1 2009 - Helaine dos Reis Flor.pdf: 3447034 bytes, checksum: 3861cf7664eb46a21add49a26a4479c2 (MD5) Previous issue date: 2009-09-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / Farfantepenaeus brasiliensis is a native species also known as the pink shrimp, and is one of the most explored fishing resources of the Brazilian coastline. This study aims to evaluate the reproductive performance of the F. brasiliensis raised in captivity submitted to different diets and sex ratios. Wild broodstock were captured in the Ba?a de Sepetiba, near to the Restinga da Marambaia and were kept for 107 days in maturation tanks at the Esta??o de Biologia Marinha da Universidade Federal Rural do Rio de Janeiro (EBM-UFRRJ). After ten days of acclimatization, the animals were randomly assigned to 18 polyethylene tanks, 450L volume, with constant aeration, continuous filtered seawater exchange, feeding trays and pieces of PVC pipes to serve as shelter. Each tank stored six animals. The experimental design was completely randomized with six treatments and three repetitions for each. Three diet feeding protocols were evaluated: A- 25% commercial diet /75% fresh food; B- 50% commercial diet 50% fresh food e C- 75% commercial diet /25% fresh food and two sex rations (male:female) 1:1 and 1:2 were evaluated. Females shrimp were unilaterally eyestalk ablated and marked with alternate cuts on the uropods for individual identification. The number of spawns, fecundity and hatching rate were used as the criteria for evaluation of reproductive performance. The 1M:2F sex ratio and the B feeding protocol had the best results regarding reproductive performance related to number of eggs/female and total egg production. Treatments that used the C diet presented the best hatching rates, despite of the low number of spawns. Throughout the experiment moulting occurred, however the spawning stopped between the 81st and the 90th day, probably due to physiological stress. At the end of the experiment, the females presented low survival rate in every treatment, possibly due to handling stress occurred during the gonadal maturation checks. Overall results of the present study indicated that it is possible to reproduce the F. brasiliensis in captivity, in small tanks, showing satisfactory reproductive performance. Nevertheless, it is necessary to re-evaluate the animal handling, in order to decrease the mortality and optimize the performance in captivity. / Farfantepenaeus brasiliensis ? uma esp?cie nativa conhecida como camar?o-rosa, e um dos recursos pesqueiros mais freq?entes e explorados na costa brasileira. Este trabalho teve como objetivo avaliar o desempenho reprodutivo de F. brasiliensis em cativeiro submetidos a diferentes dietas e propor??es sexuais. Os reprodutores selvagens foram capturados na Ba?a de Sepetiba, pr?ximo ? Restinga da Marambaia e mantidos durante 107 dias em tanques de matura??o na Esta??o de Biologia Marinha da Universidade Federal Rural do Rio de Janeiro (EBM-UFRRJ). Ap?s dez dias de aclimata??o, os animais foram distribu?dos aleatoriamente em 18 tanques de polietileno com volume ?til de 450L, com aera??o constante, fluxo cont?nuo de ?gua do mar filtrado, bandejas de alimenta??o e peda?os de canos de PVC para servir de abrigo para os animais. Em cada tanque foram colocados 6 animais. O delineamento experimental foi inteiramente casualizado com seis tratamentos e tr?s repeti??es cada. Foram avaliadas tr?s dietas alimentares: A-25% ra??o/75% alimento fresco; B-50% ra??o/50% alimento fresco e C-75% ra??o/25% alimento fresco e duas propor??es sexuais (macho:f?mea) de 1:1 e 1:2.Todas as f?meas foram abladas e marcadas com cortes alternados nos ur?podos para identifica??o individual. A avalia??o do desempenho reprodutivo foi realizada atrav?s do n?mero de desovas, fecundidade e taxa de eclos?o de cada tratamento. A propor??o sexual 1M:2F e a dieta B apresentaram os melhores resultados de desempenho reprodutivo em rela??o ao no de desovas e fecundidade. Os tratamentos que receberam a dieta C foram os que apresentaram melhor taxa de eclos?o, apesar do baixo n?mero de desovas. Ocorreram mudas durante todo per?odo experimental, por?m a ocorr?ncia das desovas cessou entre 81o e 90o dia de experimento, provavelmente por desgaste fisiol?gico. Ao final do experimento, as f?meas apresentaram alta mortalidade em todos os tratamentos, possivelmente devido ao estresse causado pelo manuseio di?rio para vistoria da matura??o das g?nadas. Os resultados obtidos no presente estudo constataram a possibilidade de F. brasiliensis reproduzir em cativeiro em tanques pequenos, apresentando desempenho reprodutivo satisfat?rio. Por?m ? necess?rio reavaliar o manejo, para diminuir a mortalidade e melhorar a efici?ncia de c?pula, para otimizar o desempenho em cativeiro.
72

Reprodução, desenvolvimento e hábitos de Chelopistes meleagridis (Linnaeus, 1758) (Phthiraptera: Ischnocera) em laboratório

Pinheiro, Ralph Maturano 03 February 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-06-01T11:44:36Z No. of bitstreams: 1 ralphmaturanopinheiro.pdf: 530518 bytes, checksum: c7705e2c22719ac685677b3a3ed3fe26 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-02T12:54:45Z (GMT) No. of bitstreams: 1 ralphmaturanopinheiro.pdf: 530518 bytes, checksum: c7705e2c22719ac685677b3a3ed3fe26 (MD5) / Made available in DSpace on 2016-07-02T12:54:45Z (GMT). No. of bitstreams: 1 ralphmaturanopinheiro.pdf: 530518 bytes, checksum: c7705e2c22719ac685677b3a3ed3fe26 (MD5) Previous issue date: 2012-02-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A bionomia de Chelopistes meleagridis fora do hospedeiro foi observada com o objetivo de compreender aspectos relacionados ao ciclo de vida desta espécie. Para isto, adultos de C. meleagridis foram coletados e colocados em condições controladas para se reproduzir, oferecendo-se pena como alimento. Da prole destes adultos, foi observado o desenvolvimento de 150 indivíduos desde o ovo até a fase adulta. Para 75 destes, foi oferecida a dieta composta de pena, enquanto para os outros 75 a dieta foi composta de pena e pele do hospedeiro (peru, Meleagris gallopavo). Ao verificar que a dieta “pena + pele” foi a que resultou no maior número de adultos, foram observadas a fertilidade, fecundidade e a longevidade de piolhos criados in vitro desde o primeiro ínstar alimentados com esta dieta. Valores altos relacionados à reprodução desta espécie foram encontrados em relação a outros piolhos da subordem Ischnocera, destacando-se: número de ovos produzidos por dia e número de ovos produzidos por fêmeas durante a vida (médias de 2,54 e 26,61 ovos, respectivamente, para fêmeas selvagens e 2,11 e 29,33 ovos, respectivamente, para fêmeas criadas in vitro.). A inclusão de pele na dieta foi determinante para o desenvolvimento até o estágio adulto, uma vez que 48% dos piolhos alimentados com essa dieta atingiram a fase adulta. Quando foi oferecido apenas pena, 1,3% dos piolhos atingiram a maturidade. O tempo de desenvolvimento de machos e fêmeas foi semelhante (média de 29,38 dias) sem haver diferença na proporção sexual dos adultos. / Bionomics of the large louse turkey Chelopistes meleagridis off host was evaluated to comprehend aspects related to life cycle. To this, adults was collected and put in controlled conditions for reproduce, offered feathers as food. From offspring of these adults were observed the development of 150 lice from eggs to adults. To 75 of them was given only feathers as resource of food while to others 75 lice the diet was composed by feathers and skin debris from the natural host, Meleagris gallopavo. When verified that diet composed by feather + skin resulted in more adults, was evaluated fertility, fecundity and longevity of this specie reared in vitro from first nymphs to adults feed with this diet. High values related to reproduction of this specie were found in comparison with others avian Ischnocera, like: number of eggs produced by day and number of egg produced during the lifespan of females (means of 2.54 and 26.61, respectively to wild females and 2.11 and 29.33 respectively to females reared in vitro). The addition of skin in diet was determinant to development to adult stage, once time 48% fed with this diet reared to adults while the lice feed with feathers only 1.3 % of then became adult stage. The time of development of males and females was the same (29 days). The sex rate of adults reared in vitro was 1:1.
73

The role of copulatory wound infliction on fitness in Drosophila melanogaster / Betydelsen av kopulationsskador och dess inverkan på fitness hos Drosophila melanogaster

Leandersson, Dennis January 2021 (has links)
One of the more fascinating Darwinian puzzles in sexual selection is that of copulatory wounding. For those taxa displaying this behavior, and that does not engage in traumatic insemination, the function of wound infliction during copulation remains unknown. In this study, the intention was to evaluate the purpose of copulatory wounding in Drosophila melanogaster and the consequences it might have for male and female fecundity. The present study measured the size and number of wounds that males from different stocks of Darwinian fitness imposed on females, as well as the copulation duration and the resulting fecundity. The number of wounds and the total wound size showed no apparent correlation to fecundity, but a significant difference in variation of the number of wounds inflicted on females was observed between males from two different lines of fitness. Wounded females were also considerably more common than non-wounded females, as were wounds that were paired compared to non-paired copulatory wounds. The results suggests that wounding might be an adaptive male trait and a copulatory courtship interpretable to females, implying a possible case of cryptic female choice. Since most wounds were paired, this implies that a bilaterally symmetrical organ is causing these wounds. Also, wounding was not as important for fecundity as previously thought. / Ett av de mer fascinerande Darwinistiska pusslen inom sexuell selektion är skadande under kopulationen. För de taxa som uppvisar detta beteende, och inte engagerar sig i traumatisk insemination, så är funktionen av kopulationsskador okänd. I denna studie så var avsikten att utvärdera syftet av kopulationsskador hos Drosophila melanogaster och de konsekvenser beteendet kan ha för det resulterande antalet avkomma. Denna studie uppmätte storleken och antalet skador som hanar av olika Darwinistisk fitness vållade honor, samt kopulationstiden och antalet avkomma. Antalet skador och den totala storleken av skador visade ingen signifikant korrelation till antalet avkommor, däremot uppvisades signifikanta variationsskillnader mellan hanar av två olika fitnessnivåer. Skadade honor visade sig också vara betydligt vanligare än icke skadade honor och parade skador var även vanligare än icke parade skador. Resultaten indikerade att kopulationsskador kan vara en adaptiv egenskap hos hanar och en form av uppvaktning som honorna kan tyda, vilket kan antyda ett möjligt fall av ”kryptiskt honligt val”. Eftersom de flesta skador var parade, så antyder detta att ett bilateralt symmetriskt organ orsakar skadorna. Kopulationsskador visade sig heller inte vara så viktiga som man tidigare antagit.
74

Pollution atmosphérique et reproduction humaine. / Atmospheric pollution and Human reproduction.

Giorgis-Allemand, Lise 03 February 2017 (has links)
Une fraction importante de la population est exposée à la pollution atmosphérique ; ses effets sur la mortalité et la morbidité cardiovasculaire et respiratoire sont connus, et un effet de l'exposition au cours de la grossesse sur le poids de naissance et la croissance fœtale est probable ; un effet sur le risque de naissance prématurée a aussi été suggéré par de nombreuses études, essentiellement en Amérique. En revanche, la capacité des couples à concevoir -fertilité- et les paramètres de la fertilité féminine ont été très peu étudiés en lien avec cette exposition.L’objectif de ce doctorat était de documenter un effet éventuel de la pollution atmosphérique sur la fonction de reproduction humaine et tout particulièrement sur les caractéristiques du cycle menstruel, la probabilité de survenue d’une grossesse (fertilité) et le risque de naissance prématurée.Nous nous sommes appuyés sur une cohorte de couples n’utilisant pas de méthode contraceptive (l’Observatoire de la fertilité en France) et sur treize cohortes de naissances européennes participant au projet ESCAPE (European Study of Cohorts for Air Pollution Effects).Nous avons observé un allongement de la durée de la phase folliculaire du cycle menstruel (période du cycle entre le début des règles et l’ovulation) avec l’exposition de la femme aux particules en suspension dans l’atmosphère (n=158, β=1,6 jour pour une augmentation de la concentration des particules de diamètre aérodynamique inférieur à 10 µm -PM10- de 10 µg/m3 dans le mois précédant le cycle, intervalle de confiance, IC à 95%, 0,3; 2,9). En utilisant deux designs d’étude en parallèle sur la même population, l’approche des durées en cours et l’approche de cohorte prévalente, nous avons mis en évidence une tendance à une diminution de la probabilité de grossesse en association avec l’exposition à la pollution atmosphérique pour la première approche (cohorte prévalente : n=468, risque relatif de grossesse, HR : 0,69 pour une augmentation des PM10 de 10 µg/m3 dans les 70 jours précédant l’inclusion, IC à 95%, 0,43;1,12) ; la tendance était similaire avec l’approche des durées en cours (n=516, durée médiane sans contraception multipliée par 1,29 pour une augmentation des PM10 de 10 µg/m3 dans les 70 jours précédant l’arrêt de la contraception, IC à 95%, 0,97;1,70).Le risque de naissance prématurée, analysé avec un modèle de survie en prenant en compte l’exposition comme une variable dépendant du temps, n’était pas associé à divers polluants atmosphériques dans les cohortes du projet ESCAPE (n=46 791, OR=0,97 pour une augmentation du niveau moyen de PM10 de 10 µg/m3 pendant la grossesse, IC à 95%, 0,87 ;1,07). Nous avons par ailleurs mis en évidence une augmentation du risque de naissance prématurée avec la pression atmosphérique pendant le premier trimestre de grossesse et avec la température moyenne pendant le premier trimestre, au moins dans l’intervalle entre -5°C et 10°C. Nous avons montré qu’une partie de la littérature en faveur d’une association entre particules fines et risque de naissance prématurée pourrait être sujette à un biais causé par des durées de fenêtres d’exposition différentes entre les enfants nés avant terme et ceux nés à terme.Dans l’ensemble, ce travail confirme la nécessité d’utiliser un modèle de survie avec variables dépendant du temps pour étudier le risque de naissance prématurité et appelle à poursuivre les recherches concernant des effets possibles des polluants atmosphériques sur le cycle menstruel et la fertilité, pour lesquels nos travaux font partie des premiers réalisés en population générale. / A large fraction of the population is exposed to atmospheric pollution, which has known effects on cardiovascular and respiratory mortality and morbidity and probable effect on birthweight and fetal growth. So far, the biological aptitude to conceive for couples -fecundity- and the female markers of fecundity have been seldom studied in relation with this environmental exposure.The aim of this PhD was to quantify the possible association between atmospheric pollution and specific health outcomes related to human reproduction: menstrual cycle characteristics, probability of pregnancy and preterm birth risk. We relied on a population of couples not using any contraceptive method (Observatory of Fecundity in France) and on 13 birth cohorts participating in the European Study of Cohorts for Air Pollution Effects.We observed that higher levels of atmospheric pollutants during the 30 days before the start of a menstrual cycle were associated with longer follicular phase (n=158, β=1.6 days per each increase by 10 µg/m3 in particulate matters with an aerodynamical diameter of less than 10 µm -PM10; 95% confidence interval: 0.3;2.9). In the population recruited in OBSEFF study, we observed a trend for an increased time to pregnancy with short-term NO2 and PM10 levels in an original approach relying on two seldom used study designs focusing on a marker of fecundity in parallel: the prevalent cohort approach (n=468, hazard ratio of pregnancy, HR: 0.69 per each increase by 10 µg/m3 in PM10 during the 70 days before the inclusion, with a 95% CI of 0.43;1.12) and the current duration approach (n=516, median current duration of unprotected intercourse multiplied by 1.29 per each increase by 10 µg/m3 in PM10 during the 70 days before the contraception stop, 95% CI: 0.97;1.70). In the cohorts included in ESCAPE, preterm delivery risk studied by a survival model with time-dependent exposures was not associated with atmospheric pollutants levels during pregnancy (n=46,791, OR=0.97 per each increase by 10 µg/m3 in PM10 during the whole pregnancy, 95% CI 0.87;1.7). We observed an increased risk of preterm birth with higher atmospheric pressure during the first trimester of pregnancy and to some extent with temperature between -5°C and 10°C during the first trimester of pregnancy. We additionally showed that using exposure windows with different durations between cases and non-cases is a source of a bias in preterm birth studies that may impact several studies in the literature.This work demonstrated that using a survival model with time-dependent exposures is crucial to study preterm delivery risk. It appeals for additional research on the possible adverse effects of atmospheric pollution on menstrual cycle and fecundity, as our studies are among the first ones conducted in a general population on those topics.
75

Sperm quality, sperm storage and fertility in male and female Drosophila melanogaster

Eckel, Barbara Angela 23 February 2023 (has links)
Sperm function is pivotal to successful sexual reproduction. The phenotype of sperm is defined by the male’s genotype and by the environment sperm encounter during their travel to the oocyte. During their functional lifespan, sperm encounter a variety of environments: After manufacture in the testis, they are stored in males before they are ejaculated along with seminal fluids and transferred to and stored in females for hours up to years before getting a chance to fertilise an egg. The sperm environment in male and female reproductive tract will be determined by male and female genotype, but also by environmental factors that affect sperm directly or indirectly by altering male and female condition. Like somatic cells, sperm age and decline in function over time due to the accumulation of cellular damage. Reactive oxygen species (ROS) that emerge as a by-product of aerobic metabolism and environmental stress are believed to be the main cause of cell senescence. Spermatozoa are in particular susceptible to ROSinduced damage because they have only limited defence and repair mechanism. As it contains many polyunsaturated fatty acids, the sperm membrane is especially prone to peroxidation by ROS and can consequently become leaky. The condition of the sperm membrane can hence be used to assess sperm age. Sperm quality has frequently been measured as sperm viability even though this approach has several biological and technical pitfalls. I developed an osmotic sperm stress test to assess sperm quality and predict future sperm performance that circumvents several of these pitfalls. Further, using osmotic stress to challenge the sperm membrane and observing sperm viability in a longitudinal approach is probably more meaningful in predicting future sperm performance than sperm viability per se. An essential abiotic factor that affects sperm directly and indirectly during storage in males and females is temperature. Ectotherms that inhabit different climates like D. melanogaster can be expected to be locally adapted to temperatures, particularly in fitness-relevant reproductive traits. I assessed the joint and isolated effects of thermal adaptation, of rearing and of ambient temperature on sperm quality by measuring sperm osmotic stress resistance, ejaculate effects on the induction of egg-laying in females, male fertility as well as female fertility and sperm storage in two D. melanogaster strains from Zambia (warm-adapted) and two from Sweden (cold-adapted). I found complex G x E interactions on male and female reproductive traits. Sperm quality was generally higher in the cold-adapted strains and showed negative carry-over effects of hot-rearing, demonstrating the important role of male genotype and developmental temperature on sperm quality. In contrast, there were positive carry-over effects of hot-rearing on male fecundity and male and female fertilisation rate in the hot-adapted strains, supporting local adaptation to heat stress. To investigate direct effects of the female reproductive tract environment on stored sperm, I genetically manipulated female D. melanogaster with a spermathecalspecific GAL4 driver line and hoped to test proposed candidate genes associated with female sperm storage. My results suggested sperm storage defects in the driver line that may either be an unexpected side-effect of the insertion of the GAL4 driver into a spermathecal serine endopeptidase or of the genetic background of the driver line.:Chapter 1 General introduction 1 Sperm phenotype 1 Basic sperm morphology 2 Sperm ageing 3 Environmental effects on sperm 5 Male sperm storage 6 Female sperm storage (FSS) 8 Phase 1: Recruitment of sperm into storage 10 Phase 2: Sperm maintenance 11 Phase 3: Release of sperm from storage 16 References 18 Chapter 2 More pitfalls with sperm viability staining and a viability-based stress test to characterize sperm quality 29 Abstract 29 Author contributions 30 Introduction 31 Methods 33 Methods of sperm viability staining in ecology and evolution 33 Empirical study 33 Statistical analysis 38 Results 38 Methods of sperm viability staining in ecology and evolution 38 Sperm survival examined with cross-sectional vs. longitudinal sampling 43 Sperm viability in the bedbug 43 Sperm viability in the fruitfly 45 Discussion 47 SV heterogeneity 48 Protocol standardization and recommendations 49 Sperm viability vs. sperm quality 50 Sperm stratification 51 Conclusion 52 References 52 Chapter 3 Effects of temperature and thermal adaptation on sperm stored in male and female Drosophila melanogaster 56 Abstract 56 Introduction 57 Material and Methods 61 Fly populations and culture 61 Temperature treatments 62 Wing length 63 Quality of sperm stored in males 63 Male effects on female fertility 64 Female effects on sperm 64 Statistical analysis 66 Results 67 Wing length at 19° and 29°C 67 Sperm viability under osmotic stress 68 Male effects on female fertility 70 Female effects on stored sperm 73 Fertilisation rate 75 Sperm storage 77 Does the decrease in sperm predict female fecundity? 80 Discussion 82 Phenotypic plasticity vs. local adaptation 82 Sperm effects, seminal fluid effects and female effects on fertility 83 Supernumerary spermathecae 87 Conclusion 87 References 89 Chapter 4 Effect of spermathecal proteins on female fertility and sperm storage in Drosophila melanogaster 94 Abstract 94 Introduction 95 Material and Methods 99 Fly Stocks 99 UAS/GAL4 crosses and controls 101 General experimental procedure 103 Experimental fly strains 103 Parameters used to assess sperm storage capability 103 Mating procedure 104 Oviposition and progeny development 104 Part I. RNAi screen (Experiments 1 and 2) 109 Material and methods 109 Experiment 1: Preliminary RNAi screen 109 Experiment 2: RNAi screen 109 Results 110 Experiment 1: Preliminary RNAi screen 110 Experiment 2: RNAi screen 114 Part II: Spermathecal secretory function (Experiments 3 to 5) 121 Material and Methods 121 Experiment 3: Survey of fertility effects of the spermathecal secretory function 121 Experiment 4: Verifying experiment 1 122 Experiment 5: Verifying experiment 2 122 Results 122 Experiment 3: Survey of fertility effects of the spermathecal secretory function 122 Experiment 4: Verifying experiment 1 127 Experiment 5: Verifying experiment 2 128 Part III. Trpa1 and temperature effects 130 Material and Methods 130 Results 131 Sperm number and fertilisation rate 140 Discussion 151 Effect of knock-down of genes with putative role in sperm storage in SSC on fertility 151 Effect of impaired spermathecal secretory function on fertility 153 Effects of enhanced secretory function of the SSC on fertility and sperm storage 154 Wildtype variation in fertility (and sperm storage) with temperature 155 Conclusion 157 References 157 Chapter 5 General discussion 164 Measuring sperm quality in male and female storage organs 164 Environmental effects on sperm stored in males and females 166 Effect of the direct environment on sperm stored in females 168 Conclusion 169 References 170 Acknowledgements 175 Supplementary Material 176 Composition of corn/yeast food 176 Composition of yeast food 176 Chapter 2 176 Chapter 3 177 Full models 177 Survival and mating rate 179 Interaction plots males 181 Fertility of focal males 184 Sex ratio of the progeny of focal males 185 Female fertility 185 Chill coma recovery assay 187 Results 187 Chapter 4 189 Experiment 3 189 Experiment 6 189
76

Effect of dietary lipid sources on the reproductive performance of Nile tilapia Oreochromis niloticus

Hajizadeh Kapateh, Ali January 2009 (has links)
Traditionally, fish oil (FO) has been used extensively in aquafeeds. The stagnation in global fish oil production coupled with an increased demand for its use in aquaculture feeds, especially salmonid feeds, has greatly inflated fish oil prices. Therefore, in order to sustain the rapid growth of the tilapia industry, the dependence on these commodities in feeds should be reduced through use of cheaper and more sustainable sources of dietary lipids, such as palm oil. This study therefore investigated several, previously poorly understood, effects of palm oil on reproductive performance of the commercial tilapia species, Oreochromis niloticus; which currently ranks as second most popular species in world aquaculture. In the present study broodstock were fed on experimental diets at full and half ration regimes throughout their entire life cycle from exogenous feeding. Studies were conducted in standardised and controlled hatchery conditions, thereby reducing the potential influence of environmental variations. First feeding O. niloticus fry were fed on four diets, cod liver oil (D 1), palm oil (D 2), mixed palm and cod liver oil (D 3) (9:1 ration) and a commercial trout diet as control (D 4) (Skretting, U.K.) on a reducing ration based on fish size. The present study investigated the effect of dietary lipid sources on (1) growth performance, (2) biochemical composition of eggs (total lipid and fatty acid composition), (3) morphological parameters of eggs (total and relative fecundity, egg size, egg weight and EW:BW), (4) larval quality (larval length and weight) and (5) oocyte recruitment and its associated sex steroid hormones. Experimental diets and feeding ration significantly influenced (p<0.05) the growth performance over a period of 120 days. Total lipid and fatty acid composition of eggs originating from broodstock fed on palm oil, mixed palm and cod liver oil (9:1) or a control diet were not significantly different (P>0.05) when fed at either full (3% BWday-1) or half ration (1.5% BWday-1). The present study, however, confirmed that fatty acid composition of fish eggs reflected the fatty acid composition of the diet, although specific fatty acids were selectively utilized or retained in the eggs. The mean inter-spawning interval (ISI) increased with increasing fish size and averaged 14, 19 and 24 days for fish fed on palm oil, mixed palm and cod liver oil or control diets, respectively. The shortest ISI observed was 7 days for fish fed a palm oil diet. Total fecundity ranged from 660 - 820 eggs/clutch. Mean total fecundity was 750, 820 and 660 eggs/clutch for fish fed a palm, mixed palm and cod liver oil or a control diet, respectively, but these differences were not significant (P>0.05). However, relative fecundity and egg weight to body weight rates as a percentage (EW: BW) were found significantly differ (p<0.05) between fish fed the control diet and experimental diets. Mean egg diameter (2.2 mm) was not significantly influenced (p>0.05) by experimental diets. The egg volume, egg dry and wet weight, fertilisation and hatching rate were also not significantly different between fish fed the experimental diets. Oocyte development was classified into distinct stages based upon oocyte size, biochemical properties and structure. The recrudescence to these stages was not significantly influenced by broodstock fed experimental diets either at full or half ration. Steroid hormones and histological analyses provided valuable data concerning the oocyte development and recruitment in this species. Levels of 17ß-oestradiol (E2) and testosterone (T) peaked within 6 days of spawning, suggesting that vitellogenesis began as early as day 2 or 3 post-spawning. By day 6, ovaries were dominated by large late-vitellogenic/maturing oocytes (stages 6 & 7) occupying about 70% of the ovary. Gonadosomatic index (GSI) reached maximal levels by day 6. It is suggested that pre-vitellogenic oocytes are recruited into vitellogenic growth immediately after spawning and complete vitellogenesis on day 6 post-spawning. Finally, the present study investigated the effect of food restriction at two rations (full and half) on broodstock reproductive performance. Oreochromis niloticus were rationed from first feeding and throughout their life-cycle. The dietary regime, full ration (3%) and half ration (1.5%), influenced fish size but despite this variation no significant differences (p>0.05) were detected in total lipid and fatty acid composition in the eggs, total fecundity, egg diameter, total egg volume and larval size. These results suggested that despite large differences in food availability throughout their life cycle, investment in reproduction had remained remarkably consistent. It appeared that during food restriction, O. niloticus sacrificed body weight and growth so as to maintain reproductive investment. In summary, this study provides valuable information using a novel experimental design on the effects of dietary lipid sources on reproductive performance of female O. niloticus. Substituting palm oil for fish oil as the dietary lipid source and reducing ration by half (1.5% BWday-1) had no significant effect on reproductive performance. Therefore it is suggested that under controlled conditions, lipids of non-marine origin, such as palm oil, can be successfully substituted for broodstock diets. Halving feed requirement should also increase profitability of seed production. KEYWORDS: Tilapia; O. niloticus; palm oil; diet; fecundity; spawning periodicity; oocyte recruitment; reproductive performance.
77

Mikroparaziti a plodnost perlooček rodu Daphnia na gradientech v korytovitých přehradních nádržích / Microparasites and fecundity of Daphnia at environmental gradients of canyon-shaped reservoirs

Hubová, Jana January 2015 (has links)
The original aim of my diploma thesis was examination of fixed samples of cladocerans from the Daphnia longispina species complex from reservoirs Vír and Vranov for the presence of 4 groups of microparasites: microsporidia, oomycetes, the protozoan Caullerya mesnili, and the yeast Metschnikowia bicuspidata. The next aim was to determine the effect of parasites on Daphnia fecundity, and determination of their spatial and temporal distribution within reservoirs. From the total number 4452 of examined Daphnia females, however, only 56 individuals were infected. This number was not sufficient for the planned analyses. As I recorded for all examined individuals the clutch size, I thus dealt to a large extent with an alternative issue: the temporal and spatial variation of, and the influence of environmental factors on Daphnia fecundity. Both studied reservoirs are characteristic by canyon-shaped profile that allows formation of environmental gradients on the horizontal as well as vertical axis. The results confirm that reservoir identity, season, and location within the reservoir (or gradient of food supply) have all significant effects on fecundity. During my work I have encountered difficulties associated with determining microparazites from fixed zooplankton samples. The appendix section of my thesis...
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Not what you expect: assortative male choice without assortative pairing pattern in a Nephila spider / Não é o que você espera: escolha assortativa do macho sem padrão de pareamento assortativo em uma aranha Nephila

Pollo, Pietro 20 July 2018 (has links)
Male mate choice occurs in species in which males face high mating costs, leading to few opportunities to copulate. Additionally, if male-male competition is strong, male mate choice should be influenced by male fighting ability. Good competitors should choose high quality females because they may be able to fight off contenders, while poor competitors should choose lower quality females. In Nephila clavipes spiders, males have limited sperm supply and fight for access to females. Here, using field experiments and observational data, we tested whether female quality and male size (a proxy of fighting ability) affect the pairing likelihood of males. In our experiments, we found that males did not express mate choice initially, but, after a few hours, chose their mates based on female size and female recent pairing status. Importantly, male mate choice direction and intensity varied with male size, as large males guarded larger females that were not recently paired and small males guarded smaller females that were recently paired. The observational data provided little evidence of assortative pairing regarding body size. With our field experiments, we show that crucial information can be collected by assessing mate choice in multiple moments. Taken together, our findings reveal the importance of considering male traits and the social context in understanding variation in male mate choice, which is often neglected in empirical studies / A escolha de parceiras por machos ocorre em espécies em que machos sofrem altos custos associados ao acasalamento, o que gera poucas oportunidades para copular. Adicionalmente, se a competição entre machos é intensa, a escolha de parceiras por machos deveria ser afetada pela habilidade de luta dos machos. Bons competidores deveriam escolher fêmeas de alta qualidade porque eles seriam capazes de afastar rivais, enquanto maus competidores deveriam escolher fêmeas de má qualidade. Em aranhas da espécie Nephila clavipes, machos possuem um estoque limitado de esperma e lutam pelo acesso a fêmeas. Usando experimentos de campo e dados observacionais, testamos se a qualidade das fêmeas e o tamanho dos machos (variável operacional de habilidade de luta) afetam a probabilidade de pareamento dos machos. Nos nossos experimentos, vimos que machos não expressam escolha de parceiras inicialmente, mas, depois de algumas horas, escolhem parceiras baseado no tamanho e no estado recente de pareamento delas. A direção e intensidade da escolha de parceiras por machos variou com o tamanho dos machos, pois machos grandes guardaram fêmeas maiores que não estavam pareadas recentemente, enquanto machos pequenos guardaram fêmeas menores que estavam pareadas recentemente. Nossos dados observacionais forneceram pouca evidência para pareamento assortativo referente a tamanho corporal. Com nossos experimentos de campo, mostramos que informação crucial pode ser coletada avaliando a escolha de parceiras em diferentes momentos. Em conjunto, nossos resultados revelam a importância de considerar características dos machos e contexto social no entendimento da variação na escolha de parceiras por machos, que é comumente negligenciada em estudos empíricos
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Estudo da fauna de Anacroneuria (Plecoptera: Perlidae) na Bacia Hidrográfica do Rio dos Sinos, Estado do Rio Grande do Sul, com dados sobre a fecundidade de Anacroneuria trimacula / Study of the fauna of Anacroneuria (Plecoptera: Perlidae) from the Rio dos Sinos basin, and data on the fecundity of Anacroneuria trimacula

Ribeiro, Valdelânia Ribeiro de 08 December 2006 (has links)
Plecoptera é uma ordem relativamente pequena e primitiva de insetos. São conhecidas cerca de 2000 espécies pertencentes a 16 famílias. No Brasil são conhecidas duas famílias, Gripopterygidae e Perlidae. Dois gêneros são registrados no Estado do Rio Grande do Sul, Anacroneuria e Kempnyia. O objetivo deste estudo foi inventariar a fauna de Anacroneuria na bacia hidrográfica do Rio dos Sinos, Rio Grande do Sul. Além disso, devido à ausência de estudos sobre fecundidade de Perlidae para a região Neotropical, especialmente Anacroneuria, também objetivou determinar as taxas de fecundidade potencial e realizada de A. trimacula do referido Estado. Foram utilizados adultos coletados junto a rios da região de nascente do Rio dos Sinos, com a técnica de atração luminosa. Os adultos foram acondicionados em álcool etílico 80% e identificados com o auxílio de estereomicroscópio. Onze fêmeas de A. trimacula foram selecionadas, dissecadas e seu ovários analisados. Duas espécies novas foram descritas, Anacroneuria fiorentini e A. caraa, e outras oito espécies foram registradas: A. cathia Froehlich 2002, A. debilis (Pictet 1841), A. flintorum Froehlich 2002, A. fuscicosta (Enderlein 1909), A. plaumanni Jewett 1959, A. stanjewetti Froehlich 2002, A. trimacula Jewett 1959, e A. uyara Froehlich 2002. Além disso, em A. trimacula foram encontrados 398 ovos maduros, em média, variando de 302 a 491, valores referentes à fecundidade realizada da espécie. Também foi encontrada uma média de 120 ovaríolos, cada um com cerca de nove ovócitos, sendo 1500 o número total médio de ovos produzidos por fêmea, correspondendo à fecundidade potencial da espécie. / Stoneflies are ancient and relatively primitive insects. Plecopterans number about 2000 species belonging to 16 families. In Brazil two families are known, Gripopterygidae and Perlidae. Two genera of Perlidae have been reported from Rio Grande do Sul State, Anacroneuria and Kempnyia. The intention of this work was to inventory the Anacroneuria fauna in the Sinos River catchment, Rio Grande do Sul. Moreover, given the absence of studies on Perlidae fecundity for the Neotropical region, especially Anacroneuria, another aim of this study was to determine the realized and potential fecundity of A. trimacula from the metioned State. Adults were collected next to rivers of the region of spring of the Sinos River, with light trap. The adults had been preserved in 80% ethanol and they were observed under a stereomicroscope. Eleven females of Anacroneuria trimacula were dissected to determine the number of eggs and ovarioles. Two new species were described, Anacroneuria fiorentini and A. caraa, and eight more were reported: A. cathia Froehlich 2002, A. debilis (Pictet 1841), A. flintorum Froehlich 2002, A. fuscicosta (Enderlein 1909), A. plaumanni Jewett 1959, A. stanjewetti Froehlich 2002, A. trimacula Jewett 1959, and A. uyara Froehlich 2002. Moreover, in A. trimacula were found 398 mature eggs, on average, ranging from 302 to 491. These values may be considered as the realized fecundity of the species. A great number of ovarioles was found, each with about 9 oocytes. The total number of eggs may be greater than 1500 per female and it corresponds to the potential fecundity of the species.
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Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)

Begum, Mahmuda January 2004 (has links)
Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.

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