Academic literature on the topic 'Broodstock nutrition'

Many of the hypotheses and proposals presented here on the role of nutrition in lobster recruitment have been derived from research on other aquatic animals. Little research has focused on the determination of nutritional requirements of lobsters and even that has been primarily with small juveniles (36–1000 mg). Despite the tacit acknowledgement that maternal fecundity and egg viability are a function of quantity and quality of available food, little is known about the nutrition of reproductively mature lobsters. The importance of broodstock nutrition and possible methods for evaluating nutritional status are discussed. Information on protein, essential amino acids, vitamins, minerals, carbohydrates, and lipids is summarized. Additionally, some proposals for field application of nutritional response criteria used in the laboratory are discussed. Though research on larvae adult broodstock nutrition, effects of environmental factors (e.g. temperature, salinity, photoperiod, etc.), as well as many other aspects of nutrition is yet to be done, there is "good opportunity" for nutrition to be a significant part of the current lobster recruitment research program.

The aim of this study was to increase our knowledge about the nutritional needs of walleye (Sander vitreus (Mitchill, 1818)) broodstock. Two dietary treatments were tested: the first consisted of frozen Atlantic mackerel (Scomber scombrus L., 1758) pieces with a supplement of experimental dry pellets and the second consisted of frozen Atlantic mackerel pieces with a supplement of commercial trout pellets. Hatching success was highest in eggs from the wild broodstock. Eggs and larvae from wild fish were characterized by the highest levels of linoleic (LOA; 18:2 n–6) and linolenic (LNA; 18:3 n–3) fatty acids in the neutral lipids. They had the lowest level of docosahexaenoic acid (DHA) in both neutral and polar lipids. The results suggest the importance of the amino acids leucine, lysine, methionine, and serine for better egg survival. Vitamin A1 content was similar in eggs from wild fish and the younger broodstock from both treatment groups, but was 10 times lower in eggs from older broodstock. Vitamin A2 was highest in eggs from wild fish. Our results showed that neither of the two diets really resulted in egg or larval quality that were comparable with that of wild fish.

AbstractThe present study investigated the effects of nutritional programming through parental feeding on offspring performance and expression of selected genes related to stress resistance in a marine teleost. Gilthead seabream broodstock were fed diets containing various fish oil (FO)/vegetable oil ratios to determine their effects on offspring performance along embryogenesis, larval development and juvenile on-growing periods. Increased substitution of dietary FO by linseed oil (LO) up to 80 % LO significantly reduced the total number of eggs produced by kg per female per spawn. Moreover, at 30 d after hatching, parental feeding with increasing LO up to 80 % led to up-regulation of the fatty acyl desaturase 2 gene (fads2) that was correlated with the increase in conversion rates of related PUFA. Besides, cyclo-oxygenase 2 (cox2) and TNF-α (tnf-α) gene expression was also up-regulated by the increase in LO in broodstock diets up to 60 or 80 %, respectively. When 4-month-old offspring were challenged with diets having different levels of FO, the lowest growth was found in juveniles from broodstock fed 100 % FO. An increase in LO levels in the broodstock diet up to 60LO raised LC-PUFA levels in the juveniles, regardless of the juvenile’s diet. The results showed that it is possible to nutritionally programme gilthead seabream offspring through the modification of the fatty acid profiles of parental diets to improve the growth performance of juveniles fed low FO diets, inducing long-term changes in PUFA metabolism with up-regulation offads2expression. The present study provided the first pieces of evidence of the up-regulation of immune system-related genes in the offspring of parents fed increased FO replacement by LO.

Four different wreckfish (Polyprion americanus) broodstock batches were maintained in research facilities under different photo and thermo-period conditions, one in Greece, the Helenic Center for Marine Research (HCMR, n = 3) and three in Spain: Instituto Español de Oceanografía (IEO, n = 13) in Vigo, Aquarium Finisterrae (MC2, n = 21) in A Coruña and Consellería do Mar (CMRM, n = 11). The CMRM includes two centers that work together: Instituto Galego de Formación en Acuicultura (IGAFA) and Centro de Investigacións Mariñas (CIMA), both in Pontevedra. During the five years of the project DIVERSIFY (Exploring the biological and socio-economic potential of new-emerging candidate fish species for the expansion of the European aquaculture industry, 2013–2018) works focused on the reproductive biology of the species, broodstock, and larvae nutrition and development of incubation and larval rearing protocols have been carried out. In terms of reproduction, catch methods of new wild animals, the reproductive cycle, sperm characteristics evaluation, and spontaneous and induced spawning methods have been described for wreckfish. Regarding nutrition, the positive effect of two types of enrichment on the fatty acid profiles of Artemia and rotifer has been verified. The relationship between the fatty acid profile of the diets supplied to the broodstock and the fatty acid profile obtained in the oocytes and eggs of the females fed with different diets, has also been demonstrated. Finally, early larval ontogeny has been described and incubation and larval rearing protocols have been proposed based on the results obtained in the different experiments of temperature, growth, survival, and larval feeding that were carried out.

Dietary supplementation with phytobiotics is a promising area in fish nutrition towards promoting the growth and health status of cultured fish. This experiment was conducted to determine the effects of Aspilia africana leaves-paste (AAL) on the growth, haematology and serum biochemistry of Clarias gariepinus broodstock. Experiment was carried out in a 24 net-happa (0.6m x 1.07m x 1.2m) suspended in an earthen pond (30 m x 5 m x 1.2m). Forty-eight (7 months old fish, 24 males (0.80±0.04kg) and 24 females (0.70±0.03kg)) were stocked at two fish per net-happa under four treatments in six replicates in a completely randomized design. Four diets (40% crude protein) were formulated to contained: control (0%); AAL1 (0.5%); AAL2 (1%) and AAL3 (1.5%). Fish were fed ad libitum twice daily for 16 weeks. Data on all parameters were analyzed using ANOVA. The highest mean weight gain, MWG: 3.13±0.15kg and lowest feed conversion ratio, FCR: 1.30± 0.04 were recorded in broodstock fed 1.5% AAL3. The lowest MWG (1.27±0.03kg) and highest FCR: 1.72±0.03) were obtained in broodstock fed control diet. The lowest packed cell volume: 15.83 ± 0.17 % and haemoglobin: 5.25 ± 0.1 (g/dL) were recorded in fish fed 1% and 1.5% AAL. No significant differences in the total protein and creatinine values obtained between fish fed 1% and 1.5% AAL. The study recommended the dietary inclusion of 1.5% A. africana leaves-paste to effectively promote growth and nutrient utilization of cultured C. gariepinus broodstock

The interaction between essential dietary components and changes in tissue nutrient reserves, egg quality and egg composition, were studied from 60 d before and during the spawning of Sparus aurata broodstock. Fish were given isonitrogenous (550 g/kg dry weight) and isolipidic (100 g/kg dry weight) diets, based on protein and lipid extracts of squid meal. Diets differed in the levels of n−6 (10–30 mg/g dry weight) and n−3 (0–10 mg/g dry weight) essential fatty acids. The effects of these diets on biochemical and fatty acid composition of body tissues, and the subsequent effects on egg composition and egg viability were measured. Dietary essential fatty acids were mostly incorporated into the liver, ovaries, digestive tract and associated adipose tissues. The lipid composition of these tissues reached an equilibrium with dietary lipid composition within 15 d of feeding on any given diet. Muscle and gill cartilage tissues did not show any significant changes in their biochemical and fatty acid composition, even after 60 d feeding. Egg viability decreased significantly within 10 d of feeding the broodstock with a diet deficient in n−3 highly unsaturated fatty acids (n−3 HUFA). The levels of n−3 HUFA in both polar and neutral fractions of egg lipid were directly correlated with their levels in the broodstock diet. When the total amount of egg n−3 HUFA dropped below 17 mg/g dry weight, egg viability and larvae hatching rate decreased by 53% and 47 % respectively. These results suggest that the biochemical composition of organs involved in S. aurata reproduction are highly sensitive to the nutritional value of the diet, which affects egg and larval quality rapidly.

Considerando la total ausencia del desove natural y fertilización de huevos en reproductores de lenguado Senegalés (Solea senegalensis) nacidos en cautividad (G1) comparados con peces salvajes mantenidos en cautivo que son capaces de producir huevos fertilizados viables para su cultivo. Esta tesis se realizó con el objetivo de determinar la importancia dietética de los ácidos grasos, específicamente del ácido graso araquidónico (20:4n-6, ARA) y su interacción en la disfunción reproductiva presentada en peces G1. Se compararon los contenidos de lípidos y ácidos grasos (FA), la expresión génica de ciclooxigenasa (COX-2) y la producción de prostaglandinas (PGE2, PGE3, PGF2α y PGF3α) en peces maduros capturados y en peces G1. El contenido total de lípidos en peces G1 fue más alto que en peces salvajes (principalmente en el hígado); además, los peces salvajes mostraron altos niveles de colesterol (CHOL). La composición de ácidos grasos también fue distinta, particularmente en el ácido graso ARA, que fue más bajo en peces G1 (hígado, testículos y músculo). Estas diferencias en lípidos y ácidos grasos entre peces salvajes y cultivados fueron causadas principalmente por los piensos comerciales utilizados para alimentar a los peces G1. Transcritos del gen COX-2 fueron significativamente más altos en espermiducto, oviducto y branquias en machos salvajes comparados con peces G1. Además, los peces salvajes mostraron valores más altos en PG de serie-2. En tanto, las PGs de serie-3 fueron más altas en G1. Para determinar el nivel óptimo de ARA en la dieta y su efecto en la fisiología reproductiva en peces G1 de lenguado Senegalés se condujeron dos experimentos: 1) Se estudio el efecto de seis dietas diferentes enriquecidas con ARA (A= 0.7, B= 1.6, C= 2.3, D= 3.2, E= 5.0 y F= 6.0% TFA) en la composición de lípidos y ácidos grasos, prostaglandinas circulantes, esteroides en sangre (11-ketotestosterone (11-KT), testosterone (T) y estradiol (E2)) y contenido de ácidos grasos en tejido (gónadas, hígado y músculo). Adicionalmente se evaluó la expresión de los transcritos de elongasa (elovl5) y desaturasa (d4fad) en el hígado de los peces G1 (grupos A, C y F) para examinar el efecto de ARA en la regulación de estos genes. 2) Se estudio la preferencia de ARA en la dieta de los peces G1 a través del uso de alimentadores de auto-demanda. En el experimento de dosis/respuesta el contenido relativo de ARA y CHOL incrementó en respuesta al enriquecimiento de ARA en la dietas, en tanto eicosapentanoico (20:5n-3, EPA) y los ratios de EPA/ARA se redujeron. Además, las PGs de serie-3 mostraron una reducción paralela al aumento de ARA en sangre y los niveles de esteroides (11-KT and T) en machos incrementaron con el enriquecimiento de ARA en las dietas. La expresión de los transcritos elovl5 y d4fad en machos también incrementó en respuesta al contenido de ARA en las dietas. Además, se observó consecuentemente un aumento de los ácidos grasos adrénico (22:4n-6) y docosapentaenoico (22:5n-6, DPA). También se observó que ARA fue rápidamente transferido y conservado en testículos y ovarios seguido por hígado y músculo. De esta forma los peces alimentados con un 2.3 y 3.2% de ARA no mostraron diferencias en hígado, gónada y músculo comparados con el contenido en peces salvajes. Por otra parte, los resultados obtenidos en el experimento de auto-demanda demostraron que lenguado Senegalés cambia su preferencia de ARA en la dieta durante el año y estos cambios fueron correlacionados con los cambios estacionales de la temperatura del agua (r2=0.65). El valor promedio de ARA demandado durante el experimento (16 meses) fue de 3.0% y se recomendó la incorporación de un 3.2% de ARA en la dieta de reproductores G1 y posiblemente se puedan utilizar niveles más bajos de un 2.3% en periodos prolongados de alimentación (> 9 meses). En conclusión, esta tesis demostró que los peces G1 tienen un desbalance en el contenido de lípidos y ácidos grasos comparados con los contenidos nutricionales de peces salvajes, lo cual contribuye a diferencias en la fisiología reproductiva de estos peces, diferencias que fueron discutidas en relación a la defunción reproductiva descrita en peces G1 de lenguado Senegalés.
Considering the complete reproductive failure to spawn viable eggs from G1 cultured Senegalese sole (Solea senegalensis) broodstock compared to successful spawning from wild caught captive broodstock, this thesis was conducted with the aim to determine the importance of dietary essential fatty acids, specifically arachidonic acid (20:4n-6, ARA) in the reproductive dysfunction exhibited by G1 Senegalese sole. Lipids and fatty acid (FA) composition, cyclooxygenase (COX-2) activity and prostaglandins production (PGE2, PGE3 PGF2α and PGF3α) of recently caught mature wild verses mature G1 fish were studied. The total lipid of G1 fish was higher compared to wild fish in liver, and wild fish showed higher levels of cholesterol (CHOL). Moreover, differences were found in fatty acids, particularly in ARA, which was lower in G1 fish (i.e., liver, testis and muscle). The observed differences in lipids and fatty acids between wild and G1 fish were a reflection of the extruded diet used to feed the fish. Transcripts of COX-2 were significantly up regulated in sperm-duct, oviduct and gills of males wild fish compared to G1 fish. Furthermore, wild fish showed higher levels of total 2-series PGs and lower levels of 3-series. To determine optimal dietary levels of ARA and the effect of ARA in the reproductive physiology of G1 Senegalese sole two studies were conducted: 1) The effects of six different ARA-enriched diet (A= 0.7, B= 1.6, C= 2.3, D= 3.2, E= 5.0 and F= 6.0% TFA) on blood lipid and fatty acid composition, prostaglandins, blood steroid levels (11-ketotestosterone, 11-KT, testosterone, T and estradiol, E2) and fatty acid tissue levels (gonads, liver and muscle) was studied. Additionally, the expression of elongase (elovl5) and desaturase (d4fad) transcripts was assessed in the liver of fish (groups A, C and F) to examine the effects of ARA on the regulation of these genes. 2) The preferred dietary ARA level of G1 Senegalese sole was studied using self-feeders. In the dose/response experiment ARA and CHOL relative content increased in an ARA dose related manner whereas EPA and EPA/ARA ratio were reduced. Furthermore, PGs 3-serie were reduced in parallel to increased blood ARA levels, and the steroids (11-KT and T) levels increased significantly with ARA-enriched diet in males. The expression of elongase (elovl5) and desaturase (d4fad) transcripts also increased in response to dietary ARA content in males, showing a pattern of up-regulation in both transcripts, with a subsequent increase in adrenic (22:4n-6) and docosapentaenoic (22:5n-6, DPA) acids. Arachidonic acid (ARA) was rapidly transferred and conserved in testis and ovary, followed by liver and muscle. Thus, fish fed 2.3 and 3.2% ARA showed no differences in the composition of testis, ovary and liver compared with the same tissues of wild fish. Moreover the results obtained by the self-fed study showed that Senegalese sole changed preference for ARA during the year and preferred ARA levels were correlated with the seasonal water temperature changes (r2=0.65). The average ARA level demanded was 3.0% TFA for all the experimental period (16 months) and dietary levels of 3.2% ARA can be suggested as optimal and possibly a lower level of 2.3% over extended feeding periods (> 9 months). In conclusion, this thesis demonstrated that G1 Senegalese sole had an imbalance in lipids and fatty acid nutritional status compared to wild sole that contributed to significant differences in reproductive physiology. These differences were discussed in relation to the reproductive dysfunction that has been described in G1 Senegalese sole.

Cod hatcheries rely greatly on wild-caught broodstock as egg quality from farm-reared broodstock tends to be poor. Broodstock diet and levels of essential fatty acids have been linked to fecundity and egg quality in cod. Arachidonic acid (ARA) and astaxanthin (Ax) are important nutrients linked to fish egg quality and differences in levels have ben found between eggs from wild and farmed cod. The aim of this thesis was to investigate the impact of dietary supplementation with ARA and Ax on fecundity and egg quality in cod. The first experiment investigated the effect of feeding a diet supplemented with ARA, for 1, 2 or 3 months prior to peak spawning. Results showed that supplementation increased ARA in eggs and that Groups fed the supplement had improved fecundity and egg quality (though with no correlation between the duration of supplementation and number/quality of eggs). The second experiment investigated the effect of supplementation of Ax in broodstock diets on egg quality in farmed cod and showed that Ax was taken up into eggs and that fish fed supplemented diet had improved fecundity and egg quality. The third experiment compared the effect of diet supplementation with ARA and Ax on egg quality in wild and farmed cod and showed that despite the dietary supplementation, wild origin fish performed better on a number of egg quality and fecundity indices. However, it was not possible to take the greater ages and spawning experience of the wild broodstock into account, which may have influenced the results. The fourth experiment measured lipid and fatty acid profiles of eggs from two UK cod hatcheries. Variation was found between farms and across seasons. Results showed that supplementation of cod broodstock diet with ARA and Ax had a positive impact on egg quality and fecundity, although effects were not consistent across all egg quality parameters.

Commercial aquaculture for marine species is gaining importance in todays industry. Over fishing of the natural recource has sadly meant that many of the higher predators halibut, turbot, seabass, sea bream and tuna are now financially suitable for the industry. This thesis covers a wide range of topics involving two of the most valuable marine species, namely the Atlantic halibut and European seabas, from broodstock to larval first-feeding. Broodstock husbandry and especially nutrition are often the last to receive attention. This study shows that careful management of the broodstock, firstly by the close timing of stripping, secondly enhancement of the broodstock diet with n-3 and n-6 HUFA can increase both fecundity and egg quality right up to the point where the larvae switch from endogenous to exogenous feeding. The implications for the industry for these two species are twofold. Firstly, The identification that halibut eggs can be fertilised within 6 hours of ovulation with no detrimental effects on fertilisation rates and subsequent egg performance means that eggs could be transported to specialist egg and larval rearing units. Thus the potential exists for the industry to be divided into separate units dealing with different stages of the life cycle much like the salmon industry. Secondly, the development of an artificial pelleted brood stock diet would mean that problems of consistency and quality and also the dangers of disease infection via the feed can be removed from broodstock management. The stage of first-feeding for halibut is still considered to be the main bottleneck in the production of this species. The current work has shown that small systems of 100-1 can be used to successfully rear halibut larvae. Although careful consideration must be made of the system design to ensure that predator (larvae) and prey (Artemia) remain homogeneously dispersed. Also, the need to use rotifers at first feed has been shown to be unecessary. However, nutrition of first-feeding larvae still requires the use of wild zooplankton to ensure successful pigmentation. Yet, Artemia supplied with commercial enrichments still perform adequately in terms of their overall growth.

Feeds that maximize reproductive potential are needed to ensure success of captive broodstock. Nutritional requirements for somatic growth of juvenile fishes differ from nutritional requirements of mature fishes and are largely species-specific. Broodstock nutritional research has focused primarily on lipid and fatty acid requirements and their effects on reproductive conditioning due to the importance of these nutrients in providing metabolic energy and structural elements, i.e. for phospholipids for embryonic development. Development of suitable broodstock feeds are limited by not knowing fatty acid requirements for many species. Once requirements are identified, plant, grain, marine, algal, and fungal lipid sources can be blended to develop least-cost diet formulations. The objectives of this dissertation are to (1) evaluate white bass Morone chrysops ovum fatty acid composition and reproductive performance after feeding maternal broodstock graded levels of squid to fish oil; (2) evaluate flax, canola, and corn oils as alternatives to marine oil(s) in white bass maternal broodstock diets; (3) determine extent to which grain oils can replace marine oils in female white bass broodstock diets in order to maintain reproductive performance and quantify fatty acid utilization of larvae with different initial fatty acid profiles; and (4) assess dietary supplementation of 20:4n-6, 20:5n-3, and 22:6n-3 concentrates to boost reproductive performance of female white bass fed primarily plant oil-based lipid sources. Of the marine and plant oils tested, menhaden fish oil provided female white bass broodstock the fatty acids (~3.9% n-3 long-chain polyunsaturated fatty acids; LC-PUFA; dry matter basis) necessary to maximize embryonic survival; however, flax oil, due to its low 18:2n-6 and high 18:3n-3 content, showed promise as a suitable plant oil candidate for partial if not complete marine oil substitution in female white bass broodstock feeds. Differential responses in embryonic and larval survival resulted in comparable total larval yields at 5 days post hatch (DPH) after feeding female broodstock graded levels (0, 33, 67, or 100%) flax to fish oils for 30 weeks prior to spawning. At the end of the endogenous feeding period, fatty acid compositions of flax and fish oil-fed broodstock progeny deviated from initial ova composition. Although n-3 LC-PUFA from menhaden fish oil are essential for embryonic survival, sunshine bass appear to have lower n-3 LC-PUFA requirements after hatch. Larval survival was highly dependent on the presence of C18 PUFA present due to flax oil inclusion in maternal diets. Embryonic survival of progeny produced from broodstock fed dietary saturated fatty acid-rich plant lipids supplemented with intact LC-PUFA concentrates (~3.4% n-3 LC-PUFA; dry matter basis) was similar to that of the broodstock fed the menhaden fish oil control diet containing 4.8% n-3 LC-PUFA. Although the dietary requirement for n-3 LC-PUFA was reduced by feeding these LC-PUFA concentrates in combination with plant lipids, menhaden fish oil is still the most viable option for least cost broodstock diet formulations intended for white bass.

The main objective of this thesis was to gain new insights in three of Florida’s high value food and stock enhancement finfish nutrition (Common snook, Florida pompano and red drum) to improve larviculture protocols. The main bottleneck in snook production is the extremely low larval survival rate, which hinders subsequent research. This work first focused on the source of the larvae by looking at potential nutritional deficiencies in captive broodstock. The lipid composition of wild and captive common snook broodstock were compared to identify disparities and gain the information necessary for the formulation of a suitable diet for captive stocks. Results showed that captive snook lipid content was significantly higher than that of wild fish. However, cholesterol and arachidonic acid (ARA) levels were significantly lower compared to wild broodstock, with potential impact on steroid and prostaglandin production, reproductive behavior and gametogenesis. Eggs from captive broodstock incorporated high docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels and low ARA levels. Consequently, ARA/EPA ratio in captive eggs was more than half of that in wild eggs (2.3 ± 0.6 and 0.9 ± 0.1 respectively), with a probable perturbation in eicosanoid production and adverse effects on embryo and larval development. The large differences observed between wild and captive broodstock most likely contributed to the reproductive dysfunctions observed in captive snook broodstock (e.g. incomplete oocyte maturation, low milt production and poor egg quality). In addition, the presence of hydrocarbons was detected in the liver of most of the wild snook sampled. This requires further investigation to identify the source of the contamination, monitor a potential impact on reproductive performances and protect the species habitat. Another major bottleneck in marine fish rearing occurs during the transition from endogenous feeding to exogenous feeding, with mass mortality events linked to inadequate first feeding diets. To gain insight on the early fatty acid requirements and mobilization of pompano and snook larvae, the pattern of conservation and loss of fatty acids from the yolk sac during the endogenous feeding period and subsequent starvation was studied. In both species, fatty acids were utilized as an energy source after hatching. Mono-unsaturated fatty acids were catabolized, while saturated and poly-unsaturated fatty acids were conserved. High levels of arachidonic acid (ARA) in pompano and snook eggs (respectively 2.44 ± 0.1 and 5.43 ± 0.3 % of total fatty acids), as well as selective retention in the unfed larvae, suggested a high dietary requirement for this fatty acid during the early stages of larval development. The effect of an ARA supplementation was therefore investigated in snook larvae at the rotifer feeding stage. Larvae receiving the supplementation did incorporate higher levels of ARA, and DHA/EPA and ARA/EPA ratios were successfully modified to match those observed in wild eggs. No significant improvements in growth or survival were observed, however the success in fatty acid profile modification suggest a possible impact of the supplementation on a longer period of time and a possible effect on stress resistance. Probiotics have been shown to enhance larval performances of several species and this strategy was therefore investigated to evaluate a potential impact on Florida pompano, red drum and common snook larvae. The effect of a commercial mix of Bacillus sp. was studied on larval survival, growth and digestive enzyme activities. Larvae were fed either live feed enriched with Algamac 3050 (Control), Algamac 3050 and probiotics (PB), or the previous diet combined with a daily addition of probiotics to the tank water (PB+). Microbiological analyses were performed at the end of the pompano trial. Numbers of presumptive Vibrio sp. were low and not statistically different between treatments, therefore no additional microbiological analyses were performed on the system. At the end of the pompano and snook trial, standard lengths of larvae from the PB and PB+ treatments were significantly greater than for the control larvae. For both pompano and snook, trypsin specific activity was higher in PB and PB+ larvae compared to the control larvae. Similarly, alkaline phosphatase activity was higher for the pompano larvae fed the PB and PB+ treatments and for the snook larvae fed the PB+ treatment compared to the control larvae. No enhancement of growth or digestive enzymes activities was observed in red drum larvae. Yet, no negative effects were noticed and a longer trial period and the study of additional parameters could reveal different effects. In all three species, survival was not affected by the supplementation; however, stress exposure should be further investigated as the supplementation may strengthen the larvae, especially pompano and snook larvae where the Bacillus sp. supplementation appears to promote growth through an early maturation of the digestive system. Another key challenge in marine fish larval rearing resides in weaning the larvae onto dry micro-diets. This step is commonly concurrent with larvae metamorphosis into juveniles, with extensive morphological and physiological changes that are likely to influence nutritional requirements. In the present project, three microdiets were tested on weaning of Florida pompano larvae: Otohime, Gemma and a reference diet LR803. The experimental system was stocked with 11-day-old larvae, which were co-fed micro-diets and live food from 11 dph to 17 dph then micro-diets only until 28 dph. Survival from 11 dph to 28 dph was similar for all treatments, with an average of 33 %. At the end of the trial, the Gemma larvae were significantly longer and heavier than larvae fed the other diets. Fatty acid composition of the diets and larvae varied significantly between treatments. The Gemma larvae incorporated the lowest amount of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (ARA). However, they presented the highest DHA/EPA and ARA/EPA ratios, supporting the concept that the proportions of polyunsaturated fatty acids are of greater importance than their absolute amount. Results from the enzyme analysis showed that fishmeal is a suitable main source of protein for Florida pompano larvae and demonstrated the full functionality of the pancreas at 16 days post hatch. These results provide the basis of a suitable weaning diet for pompano larvae and indicate the possibility of a weaning time prior to 16 days post hatch, which is of high interest in commercial production. Overall, this research provides new data on common snook, pompano and red drum nutritional requirements with results that can be directly applied to help overcome major bottlenecks in the hatchery phase and improve rearing protocols.

L’objectif de cette thèse a été d’étudier le rôle du sélénium (Se) dans l’alimentation des géniteurs de truites arc-en-ciel et leur progéniture (génération F1). Les aliments à base d’ingrédients végétaux ont été supplémentés avec 0,3 ppm de Se apporté sous forme inorganique (sélénite de sodium) ou organique (hydroxy-sélénomethionine, OH-SeMet). Le Se, plus particulièrement la forme organique, dans l’alimentation des géniteurs a amélioré les performances de reproduction et augmenté les teneurs corporelles en Se de la progéniture avant le premier repas. Chez la progéniture F1, la distribution tissulaire du Se a été affectée à la fois par le Se présent dans l’aliment des géniteurs et celui des alevins. L’OH-SeMet a amélioré nettement la teneur en Se du muscle alors que le sélénite de sodium de l’aliment des alevins a augmenté le teneur en Se du foie. A court terme, les défenses anti-oxydantes avec notamment la glutathion peroxydase (GPx) ont été stimulées par la supplémentation en OH-SeMet des géniteurs, même si une diminution du rapport glutathion réduit/glutathion oxydé a également été notée. Nous avons pu montrer que la supplémentation en Se des géniteurs pouvait entraîner des modifications à long terme du métabolisme du glutathion qui ont persisté après le début de l’alimentation exogène. Une moins bonne résistance au stress hypoxique a été observée chez les alevins issus des géniteurs nourris avec des régimes supplémentés en Se, alors que la supplémentation en Se dans l’alimentation des alevins a amélioré la résistance au stress. L’effet antagoniste entre l’apport en Se par l’aliment ou les parents sur la GPx et les défenses anti-oxydantes pourrait être lié à une programmation nutritionnelle où soit la progéniture issue du lot contrôle compenserait les faibles niveaux alimentaires de Se, soit la progéniture issue des groupes supplémentés en Se serait moins tolérante aux faibles niveaux alimentaires en Se. Des modifications épigénétiques pourraient être à l’origine de cette programmation nutritionnelle et, en effet, nous avons montré que le niveau de méthylation de l’ADN du foie des alevins émergents était sensible à la composition en Se du régime des géniteurs, à la fois en terme de teneur et de forme. Les gènes identifiés dans cette étude indiquent que plusieurs voies métaboliques pourraient être affectées par l’alimentation en Se des géniteurs. L’ensemble de ce travail a mis en évidence des modifications à court et long terme de différentes voies métaboliques incluant les défenses anti-oxydantes par le Se d’origine parentale ou alimentaire chez les alevins de truite en interaction avec la teneur en oxygène dissous de l’eau ce qui devrait permettre à terme d’améliorer la formulation des nouveaux aliments piscicoles pour les stades géniteurs et alevins
Selenium (Se) nutrition in rainbow trout broodstock and their F1 progeny fed plant-based diets was studied. The diets were unsupplemented or added with 0.3 ppm Se as inorganic (sodium selenite) or organic (hydroxy-selenomethionine, OH-SeMet). Parental Se, especially as organic form, improved reproduction performance and increased body Se levels in the progeny before first feeding. In the F1 progeny, tissue Se distribution was modified pending on parental and dietary Se level and form. OH-SeMet efficiently raised muscle Se content, but the direct sodium selenite feeding resulted in higher liver Se levels. In short-term the antioxidant system including glutathione peroxidase (GPx) was supported by parental OH-SeMet, even if a decreased ratio of reduced to oxidized glutathione was also noticed. We found that parental Se can cause long-term modifications in the glutathione metabolism that even persist after the beginning of exogenous feeding. Fingerling showed lower stress tolerance towards hypoxia when originating from parents fed Se-supplemented diets, but direct Se feeding increased stress resistance. The contrary effect observed between direct and parental Se nutrition on the GPx and antioxidant system might relate to a nutritional programming effect, where either the progeny of the control group compensated the low dietary Se levels or the fry originating from Se-supplemented groups was less tolerant towards low dietary Se levels. Epigenetic modifications can underlay nutritional programming effects and indeed we found that the liver DNA methylation pattern at swim-up fry stage was sensitive towards the parental Se regime in terms of both Se level and form. Genes identified in the study point towards several metabolic pathways that might be affected by parental Se nutrition. Overall, this work highlighted modifications in short and long term of different metabolic pathways including antioxidant system by parental and dietary Se in rainbow trout fry in interaction with dissolved oxygen levels, which could allow further optimization of new feed formulations for broodstock and fry stages

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The goal of this study was to evaluate the effects of different levels of digestible protein (DP) and energy (DE) over growth, breeding performance and offspring quality in females of Nile tilapia (Oreochromis niloticus). Nine food formulae were evaluated using a combination of three DP levels (28, 34 and 40%) and three DE levels (2,800, 3,400 and 4,000 kcal.kg-1) in three repetitions. Fish were kept in net cages along a naturally carved tank. Temperature was measured daily while pH and dissolved oxygen values were taken weekly. The breeding management was carried out in 260 days (September 2010 to April 2010) using a sex ratio of 3 females: 1 male with ten days of resting and four days of mating. Mean weight, standard length, weight gain, condition factor, specific growth rate, feed conversion and survival rate were evaluated in females each 14 days. As for breeding performance, the analyzed parameters were: mean egg weight, egg diameter, absolute fecundity, relative fecundity and mean larval weight at hatching. For that, eggs were collected from oral cavity after mating for subsequent artificial incubation. In January 2011, offspring samples were collected and raised up to 30 days of age to evaluate growth parameters during sex reversal stage. A broodstock sample was dissected to measure visceral-somatic, hepatosomatic and gonadosomatic indexes. Water quality remained adequate to maintain this fish species, but temperature was lower than that recommended for broodstock. The tested food formulae influenced female growth (p<0.05) throughout the experimental period, as well as the visceral-somatic index in the selected month (p<0.05). In relation to reproductive features, the treatments had no effects on egg production (p>0.05). Nonetheless, energy levels affected relative fecundity (p<0.05) and protein levels influenced both egg and larval weight (p<0.05). No differences in the growth of offspring derived from broodstock fed on distinct formulae were detected (p>0.05). Thus, food formulae containing 28% of DP and 2,800 kcal of DE.kg of food -1 are indicated to Nile tilapia once they assure a higher egg production per gram of female without affecting offspring performance
O trabalho visou analisar o efeito entre os diferentes níveis de proteína (PD) e energia digestíveis (ED) sobre o crescimento, desempenho reprodutivo e qualidade da prole de fêmeas de tilápia do Nilo (Oreochromis niloticus). Foram avaliadas nove rações a partir da combinação entre três níveis de PD (28, 34 e 40%) e três níveis de ED (2.800, 3.400 e 4.000 kcal.kg ração-1) com três repetições. Os peixes foram acomodados em tanques-rede distribuídos em tanque escavado sob condições naturais. Diariamente verificou a temperatura e semanalmente o pH e oxigênio dissolvido. Os animais foram submetidos a um manejo reprodutivo com dez dias de descanso e quatro dias de acasalamento, com 3 fêmeas para 1 macho durante 260 dias (setembro de 2010 a abril de 2011). As fêmeas foram avaliadas, a cada 14 dias, quanto ao peso médio, comprimento padrão, ganho de peso, fator de condição, taxa de crescimento específico, conversão alimentar e sobrevivência. Quanto ao desempenho reprodutivo, verificaram-se os parâmetros de peso médio dos ovos, diâmetro dos ovos, fecundidade absoluta, fecundidade relativa e peso médio das larvas no momento da eclosão. Para isso, após o período de acasalamento, foi realizada coleta de ovos da cavidade bucal que foram submetidos a incubação artificial. No mês de janeiro de 2011, amostras da prole foram coletadas e mantidas em sistema de criação até os 30 dias, e verificados os parâmetros de crescimento durante a fase de reversão sexual. Uma amostra de matrizes foi dissecada para mensuração dos índices víscerossomático, hepatossomático e gonadossomático. A qualidade da água permaneceu dentro dos níveis ideais para a espécie, porém a temperatura manteve-se abaixo do recomendado para reprodutores. As rações testadas mostraram influência no crescimento das fêmeas (p<0,05) ao longo do período experimental, assim como para o índice viscerossomático no mês de coleta (p<0,05). Para os aspectos reprodutivos, as matrizes não apresentaram maior produção de ovos de acordo com os tratamentos (p>0,05). Porém, sofreram efeito dos níveis energéticos para fecundidade relativa (p<0,05) e dos níveis protéicos para peso dos ovos e das larvas no momento da eclosão (p<0,05). As proles provenientes dos reprodutores alimentados com as diferentes rações, não evidenciaram diferença no seu crescimento (p>0,05). Rações contendo 28% de PD e 2.800 kcal de ED.kg de ração-1 são indicadas para tilápia do Nilo para garantir maior produção de ovos por grama de fêmeas sem afetar o desempenho da prole

The aim of the work was to evaluate the effect of different protein and lipid sources of animal and vegetable origin on the reproductive performance of black catfish Rhamdia quelen females. Three experiments were accomplished with duration of 90 days each, divided in three phases: Phase I, Reproducers feeding; phase II, Induced reproduction and eggs and larvae incubation; phase III, Larvae culture. Fifteen females of black catfish (around 700g) were used for experiments 1 and 2, and 500g for experiment 3. The females were distributed in three net cages of 1m³, 5 fish (4 females for induction and 1 for oocyte collection). The fish were fed for ten weeks using three diets as treatments: experiment 1, meat and bone meal and soybean meal (CS), fish meal and soybean meal (PS) and yeast and soybean meal (LS); For experiment 2, the effect of substitution of the meat and bone meal for the soybean meal in increasing levels was evaluated (0%, 35%, 70%), that were treatments CS 0, CS 35 and CS 70; In experiment 3, pork fat (BP), sunflower oil (OG) and Canola oil (OC). After induced spawning, samples of ten eggs were collected at the moment of the fishes spawning, at 3, 9, 12, 18 and 24 hours. Also samples of ten larvae were collected, at the moment of the eclosion, at 12, 24, 36 and 48 hours. Three samples of larvae of each incubator in the density of 30 larvae/l, were collected and fed during 14 days. Changeable zoogenic were esteem for phases I and III and reproductive for phase II. In experiment 1, females fed with the diet of treatment LS, had shown minor profit in weight, the eggs had equally minor weight. For the embryonic evelopment treatments, CS and PS were superior to treatment LS in the variable (DSV). In the larval development in the incubators, treatment CS showed better performance for the variable (CT). For the experiment 2, females fed with diets CS 70, had not answered the spawning of fishes. The embryonic development, larval vitelline and larvae were superior in treatment CS 0 for the variable (DO and AO), (CT and AT), (CT, CP, Area, SOB) respectively. In experiment 3, the larvae development in the incubators, treatment BP was minor that treatment OG in the variable (CT), equally treatment BP was minor that treatments OG and OC for the variable (DSV). For the larval development until the 14 days treatment OC was greater that treatment BP for the variable (CT and CP). We can conclude that the use of Meat and Bone meal and Soybean meal as protein sources are presented as good option in the feeding of reproductive females of black catfish. The pork fat is so good as sunflower and canola oils as lipid sources for reproductive females and they provide good development of the embryo and jundiá s larvae
No trabalho avaliou-se o efeito de diferentes fontes protéicas e lipídicas de origem animal e vegetal sobre o desempenho reprodutivo de fêmeas de jundiá Rhamdia quelen. Foram realizados três experimentos, de 90 dias cada, divididos em três fases: fase I, Alimentação de reprodutores; fase II, Reprodução induzida e incubação de ovos e larvas; fase III, Larvicultura. Foram utilizadas 15 fêmeas de jundiá com peso aproximado de 700g para os experimentos 1 e 2, e 500g para o experimento 3. As fêmeas foram distribuídas em três tanques-rede de 1m³, sendo 5 peixes por tanque rede (4 fêmeas para indução e 1 para coleta de ovócitos) e alimentadas durante dez semanas com três dietas experimentais. No experimento 1 testaram-se Farinha de Carne e Ossos e Farelo de Soja (CS), Farinha de Peixe e Farelo de Soja (PS) e Levedura de Cana e Farelo de Soja (LS). No experimento 2, avaliou-se o efeito de substituição da Farinha de Carne e Ossos pelo Farelo de Soja na ração CS do experimento 1 em níveis crescentes, sendo os tratamentos CS 0, CS 35 e CS 70. No experimento 3, testaram-se a Banha de Porco (BP), Óleo de Girassol (OG) e Óleo de Canola (OC) como fontes de lipídios. Após desova, foram coletadas amostras de dez ovos, às 0, 3, 9, 12, 18 e 24 horas. Após a eclosão foram coletadas amostras de dez larvas às 0, 12, 24, 36 e 48 horas e medidas, e três amostras de larvas de cada incubadora foram alimentadas durante 14 dias. Foram estimadas variáveis zootécnicas para as fases I e III e reprodutivas para fase II. No experimento 1, as fêmeas do tratamento LS, mostraram menor ganho em peso, igualmente os ovos tiveram menor peso. Para o desenvolvimento embrionário os tratamentos CS e PS foram superiores ao tratamento LS na variável Diâmetro do Saco Vitelino (DSV). No desenvolvimento larval nas incubadoras, o tratamento CS mostrou melhor desempenho para Comprimento Total (CT). No experimento 2, as fêmeas alimentadas com dieta CS 70, não responderam a desova. O desenvolvimento embrionário, larval vitelino e larval foi superior no tratamento CS 0 para as variáveis (DO e AO), (CT e AT), (CT, CP, Área, SOB), respectivamente. No experimento 3, no desenvolvimento das larvas nas incubadoras, o tratamento BP foi menor que o tratamento OG na variável (CT), e igualmente o tratamento BP foi menor que os tratamentos OG e OC para a variável (DSV). Para o desenvolvimento larval até os 14 dias o tratamento OC foi maior que o tratamento BP para as variáveis (CT e CP). Conclui-se que a farinha de carne e ossos e farelo de soja (até 60% de inclusão) são boas fontes protéicas para fêmeas reprodutoras de jundiá. A banha de porco é tão eficiente quanto óleo de girassol e canola como fontes lipídicas para fêmeas reprodutoras e proporcionam bom desenvolvimento embrionário e das larvas de jundiá

This chapter focuses on advances in the farm production of the freshwater prawns (FWPs) Macrobrachium spp., primarily on M. rosenbergii. Farming FWPs is generally divided into four phases: reproduction, hatchery, nursery, and grow-out. The broodstock is held in earthen ponds or indoor tanks filled with freshwater. The hatchery is usually performed in intensive systems, using indoor tanks and brackish water, whereas the nursery phase uses freshwater in indoor tanks or in earthen ponds. The grow-out is generally performed in semi-intensive systems, using freshwater earthen ponds in monoculture, but integrated systems with fish, crabs, or rice are also very common. The production strategy is site specific and should be set up according to the species raised, climate characteristics, and the desired market size of the prawn. Productivity generally ranges from 1,000 to 4,500 kg/ha/yr, but may surpass 11,000 kg/ha/yr in tropical areas. Production is concentrated in Asia, mainly in China. Most production is traded in local markets, and FWPs are usually sold alive, but some countries, such as Bangladesh, India, and Thailand, export frozen prawns to Europe and the USA. Substantial scientific literature and more than 100 patents support the technology for farming FWPs. However, genetics, nutrition, and interaction with other species in integrated culture are still issues. The culture of FWPs has been described in detail in a number of international review papers, books and book chapters, and practical manuals. This chapter summarizes and updates the information found in those publications.

Marine ornamental decapods are among the most popular invertebrates traded in the global marine aquarium industry. With the exception of the Dendrobranchiata, nearly all other major groups of decapods have at least one species traded as ornamental, the majority being caridean and stenopodidean shrimp, as well as hermit and brachyuran crabs. Found and collected in the wild from tropical coral reefs and coastal lagoons, the aquaculture of marine ornamental decapods is yet to achieve a scale that alleviates the fishing pressure affecting natural populations. Most cultivation efforts have targeted cleaner and boxing shrimp within the genera Lysmata and Stenopus, respectively. While these species are some of the most highly traded, research on their captive culture has been mainly driven by their market value rather than conservation purposes. This is likely the reason why the aquaculture of other species that are also heavily collected, such as hermit and brachyuran crabs, is yet to properly be addressed. This chapter provides an overview of the most emblematic marine ornamental decapod species currently traded for marine aquaria, including their distinctive features, as well as their collection, packing, and shipping techniques. The state of the art of marine ornamental decapod aquaculture is critically revised, with an emphasis on broodstock husbandry and maturation, larviculture, and grow-out to commercial size. Commonly employed systems for stocking breeding pairs, raising larvae, or growing juveniles are detailed, underscoring recirculated systems operating with synthetic seawater due to their potential use in coastal or inland facilities. The main bottlenecks impairing the successful breeding of these organisms are critically addressed, namely the lack of maturation diets customized to secure the nutritional needs of target species, which consequently impairs the production of high-quality larvae for cultivation. The main constraints for larviculture are also highlighted, with special emphasis on the lack of suitable live prey and the ability of several decapod species to delay metamorphosis under suboptimal larval diets. Issues on grow-out, such as poor growth performances and cannibalism, are discussed from a commercial perspective, as well as mitigation actions (e.g., use of live prey and complex shelters). There is a strong need for science-based conservation policies, where accurate data reporting and traceability along the supply chain must be implemented to promote a sustainable use of these resources. Though pricey and popular, marine ornamental decapods are no longer poorly studied when compared to a few years ago. Nonetheless, some key issues still need the attention of researchers, commercial breeders and hobbyists to ensure that these remarkable organisms can continue to be admired in the wild and in aquarium displays.