13 research outputs found
Density and gender segregation effects in the culture of the caridean ornamental red cherry shrimp Neocaridina davidi Bouvier, 1904 (Caridea: Atyidae)
The effect of density on growth, sex ratio, survival, and biochemical composition of the red cherry shrimp, Neocaridina davidi Bouvier, 1904, was studied to determine optimum rearing conditions in this ornamental species. It was tested whether gender segregation affected growth and survival of the species. To test the effect of density (Experiment 1), hatched juvenile shrimp were kept at three different densities: 2.5, 5, and 10 individuals l-1 (D2.5, D5 and D10, respectively). To test the effect of gender segregation (Experiment 2), 30-day juveniles were reared in three conditions: culture with only females, culture with only males, and mixed culture (females: males 1:1) at 5 individuals l-1 density. Experiments lasted 90 days, and shrimp were weighted either every 30 days (Experiment 1) or 15 days (Experiment 2). At day 90, females kept at D2.5 weighted 45% more than females stocked at D10 (P 0.05). Males at D2.5 weighted 29% more than D5 and D10 (P < 0.05). Survival was high and unaffected by treatment. Sexual differentiation did not differ among treatments. Females from D2.5 had the lowest lipid and protein content, which would occur if they had a higher spawning. Males from D2.5 had higher content of proteins, probably due to their larger size. Gender segregation had no effect over growth and survival; females grew up to a larger size than males both in monosex and mixed culture. It was shown that given to their non-aggressive behavior, N. davidi is tolerant to a highdensity condition, which makes it feasible as an ornamental species.Fil: Vázquez, Nicolás Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Delevati Colpo, Karine. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Lopez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin
Effect of background color and shelters on female pigmentation in the ornamental red cherry shrimp Neocaridina davidi (Caridea, Atyidae)
Neocaridina davidi, the “red cherry” shrimp, is becoming popular in trade markets because of the reddish coloration of females. The aim of this study was to analyze the impact of background substrate color, and the presence of shelters on N. davidi female pigmentation and astaxanthin content. In the first experiment juveniles were assigned to one of three treatments: white, red, or black background substrate. After 90 days, females exposed to the black background showed higher astaxanthin content and relative carapace colored area than those exposed to white and red backgrounds. The second experiment evaluated the presence of shelters with white or black backgrounds. Juveniles were assigned to one of four treatments: white background with shelters (WS), white background without shelters (WWS), black background with shelters (BS), and black background without shelters (BWS). After 90 days the presence of shelters did not influence either the color nor total astaxanthin content. Females exposed to BWS and BS had higher astaxanthin content and relative carapace colored area than those exposed to WWS and WS. Growing N. davidi with black substrates could be a low cost and easy method to improve its economic value. Furthermore, this species could be cultivated as a pigment-enriched food source for other aquatic species.Fil: Tomas, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: López Greco, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Modeladores de la calidad de progenie en un crustáceo de interés económico, el camarón ornamental "red cherry" Neocaridina davidi (Caridea, Atyidae)
Neocaridina davidi es una especie dulceacuícola comercializada mundialmente para acuarismo y cultivada actualmente en Argentina. Pero pese a su importancia económica, hasta el momento existen pocos estudios sobre su reproducción y su cría. Por lo tanto, el objetivo de este trabajo de tesis fue evaluar las condiciones óptimas de cultivo de N. davidi que maximicen la producción de juveniles. Se evaluaron, entonces, tres factores que pueden ser manipulados en cultivo sobre la producción y la calidad de la progenie: el efecto del tamaño de las hembras y los machos del lote parental, el efecto de la coloración de la hembra, y la calidad del alimento del lote parental. Previo a evaluar el efecto del tamaño de los parentales, se estudió la variación en la forma del cefalotórax respecto al tamaño durante el crecimiento y hasta alcanzar la madurez sexual, mediante un análisis morfogeométrico. Se registraron cambios menores a lo largo de la ontogenia, relacionados al incremento en peso y se encontró un significativo dimorfismo sexual a partir de los 54 días de edad. Se encontró que el número de juveniles eclosionados de puestas provenientes de hembras grandes fue mayor al de las provenientes de hembras pequeñas. Sin embargo, no se observó asociación entre el tamaño paterno y el desempeño reproductivo de las hembras y la calidad de la progenie, sugiriendo que la contribución de los machos al desarrollo de la progenie es adecuada, independientemente de su tamaño. Por otra parte, la coloración materna está asociada negativamente a la cantidad de juveniles eclosionados por puesta, por hembra. Esto sugiere que en las hembras de esta especie hay un compromiso entre derivar carotenoides para la coloración del cuerpo y la reproducción. Por el contrario, no se encontró asociación entre la coloración materna y los otros parámetros de calidad de progenie. En cuanto a la calidad del alimento del lote parental, se ensayaron tres alimentos comerciales: un alimento para peces tropicales ornamentales utilizado previamente en la cría de N. davidi (T), un alimento específico para crustáceos (C), y un alimento para peces ornamentales de menor costo que los otros (O). El número de huevos por puesta fue similar para todas las hembras. Sin embargo, el contenido de carotenoides de los huevos provenientes de hembras alimentadas con T fue el más alto. Esta diferencia podría suponer una mayor supervivencia de estos embriones. Acorde a esto, el número de juveniles eclosionados para las hembras alimentadas con T fue mayor que para aquellas alimentadas con C u O, aunque el área ocupada por la reserva de vitelo de los juveniles al eclosionar fue similar entre dietas. En suma, en base a estos resultados se proponen mejoras en las condiciones de cultivo de N. davidi contribuyendo al desarrollo de esta actividad en nuestro país. Además estos resultados son relevantes para el incremento del conocimiento teórico sobre los factores que modelan la calidad de progenie en crustáceos decápodos.Neocaridina davidi is a freshwater species that is commercialized worldwide for aquarium keeping and that is currently cultured in Argentina. But notwithstanding its economic importance, up to the present there are only few studies regarding its reproduction and culture. Therefore, the aim of this study was to evaluate the optimal culture conditions of N. davidi that maximise juvenile production. Three factors that can be manipulated in culture over production and offspring quality were tested: the effect of female and male broodstock size, the effect of maternal colouration, and broodstock diet quality. Prior to the evaluation of parental size effect, the variation in cephalothorax shape on size during growth and until shrimps reached sexual maturity, was studied by means of a geometric morphometric analysis. Subtle changes in carapace shape were recorded along the ontogeny, and were related to size increment. A significant sexual dimorphism was found from 54 days of age. The number of hatched juveniles from large females was higher than those from small females. However, paternal size had no effect on female reproductive output and offspring quality, suggesting that males’ contribution to offspring development was adequate regardless of male size. On the other hand, maternal colouration was negatively associated to the number of hatched juveniles per brood per female. This suggests that females might trade off their carotenoid resources between body colouration and reproduction. In contrast, no association was found between maternal colouration and the other offspring quality variables studied. Regarding broodstock diet quality, three commercial diets were tested: a diet for tropical ornamental fish (T), a diet for crustaceans (C), and a diet for ornamental fish (O). The number of eggs per brood was similar for all females. However, the carotenoid content of eggs from females fed with T was the highest. This could translate in a higher embryo survival. Accordingly, the number of hatched juveniles from females fed with T was higher than those fed with C or O, although the area occupied by yolk reserves of newly hatched juveniles was similar among diets. In sum, based on these results, many upgrades in N. davidi‘s culture were proposed, contributing to the development of this activity in our country. Besides, these results increase the theoretical knowledge on the factors that model offspring quality in decapod crustaceans.Fil: Sganga, Daniela Eliana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Effect of different substrates on growth and biochemical composition of the ornamental “red cherry” caridean shrimp, Neocaridina davidi (Atyidae)
The effect of different substrates on growth, sexual ratio, number of ovigerous females and survival of the red cherry shrimp, Neocaridina davidi, was analysed to enhance its culture. Recently hatched juvenile shrimps were exposed to 4 different substrates: Vesicularia sp., Ceratophyllum sp., Cabomba sp. and a green plastic net. Growth was analysed over 90 days with shrimps being weighed every 30 days. While maximum size was similar for all treatments, maximum relative growth rate and instantaneous growth was significantly greater and peaked earlier, respectively, in shrimps cultured with Vesicularia sp. Additionally, substrate had no effect on female and male final body weights or their biochemical composition (lipid and protein content). Sexual proportion was slightly biased towards males in all treatments. Survival was highest with Vesicularia sp. (90%) and similar among the remaining treatments (nearly 60%). Shrimps grown with Ceratophyllum sp. presented the lowest proportion of ovigerous females at 10% compared to 30–48% for other treatments. Overall, shrimp culture was significantly influenced by substrates. We hypothesize that Vesicularia sp. could enhance shrimp survival by supporting an environment free of pathogens; or that the periphytic community itself could provide benefits.Fil: Vázquez, Nicolás Darío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Lopez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Egg production in relation to paternal weight in a freshwater caridean shrimp (Decapoda)
In diverse invertebrate species, sperm quantity and quality are positively correlated with male size, egg fertilization rates being consequently affected by paternal weight. This factor may also have an indirect effect on egg quality, because females could adjust the quantity of yolk stored in oocytes before spawning according to their partner attractiveness. The objective of the present study was to determine whether paternal weight influences egg production in a freshwater crustacean with external egg fertilization, the caridean shrimp Neocaridina davidi. Virgin females weighing 60-100 mg were paired with virgin males weighing 20-50 mg. The number (total and fertilized), size (volume, wet and dry weight) and carotenoid content of eggs were recorded for each pair. Paternal weight was not associated to any of the evaluated egg variables, while maternal weight showed a positive correlation with egg number and a negative correlation with egg carotenoid content. The percentage of fertilized eggs was similar and near 100% for all paternal sizes, which indicates that small mature males provided enough good-quality sperm to fertilize almost all the oocytes laid by females, similarly to larger males. The relatively low fecundity of N. davidi females may explain, at least in part, the absence of sperm limitation even under a hypothetical decrease in sperm supply by smaller males. In addition, paternal weight had no effect on egg volume, weight and carotenoid content, which suggests that females do not modulate the total amount of biochemical reserves allocated to the maturing ovary as a function of their partner size. Present results are the starting point for a future evaluation of sperm production, in terms of quantity and quality, in males of different size and physiological condition.Fil: Tropea, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: López Greco, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Sexual dimorphism in a freshwater atyid shrimp (Decapoda: Caridea) with direct development: A geometric morphometrics approach
Neocaridina davidi is a caridean shrimp that has gained popularity in recent years as an ornamental species. Using geometric morphometrics, we investigated sexual dimorphism in carapace and second abdominal segment shape of N. davidi. Adult females displayed a more elongated carapace and a longer rostrum than males. However, male carapace shape was similar to that of juvenile females. The second abdominal pleura was more elongated and wider in adult females than in males. Significant differences were found in centroid size for the carapace and the second abdominal segment between sexes, which is consistent with sexual size dimorphism. These results support the hypothesis of a "pure search" mating system in N. davidi, where small males search actively for receptive females, and after insemination they continue searching.Fil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Fernandez Piana, Lucas Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santaló". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santaló"; ArgentinaFil: Lopez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Body coloration, carotenoid content, spermatophore quality and biochemical parameters by effect of temperature in the caridean shrimp Neocaridina davidi (Atyidae)
This study analysed the effects of three temperatures (20, 24 and 28ºC) on survival, body coloration, carotenoid content, body weight, biochemical composition and spermatophore quality in the shrimp Neocaridina davidi. In all treatments, survival was >90%. Female body coloration and total carotenoid content, for both males and females, did not statistically differ among treatments. Female weight was similar for the three temperatures, while male weight was higher at 20ºC and 24ºC. Total lipid content was higher in female and male shrimps raised at 20ºC. Total protein content was higher in females exposed at 28ºC, but in contrast, males showed the lowest value at the same temperature. The histological and histochemical analyses of the male reproductive system did not reveal differences among treatments. At 20ºC, a delay in ovaries maturation was observed, as well as a smaller amount of ovigerous females at the end of the experimental period. Hence, these results suggest that a temperature range from 20ºC to 28ºC is adequate for satisfactory growth, with no change being exerted on spermatophore quality, body female coloration or carotenoid content, but biochemical composition was affected. Nevertheless, the lowest temperature had a clear impact on the metabolism and reproduction of N. davidi.Fil: Tomas, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Battista, Ariadna Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Lopez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Effect of diets on carotenoid content, body coloration, biochemical composition and spermatophore quality in the “red cherry” shrimp Neocaridina davidi (Caridea, Atyidae)
In aquarium industry trade markets, Neocaridina davidi, the “red cherry” shrimp, is one of the most attractive ornamental shrimps due to the striking reddish coloration of females. Five commercial diets formulated for ornamental species were evaluated over a 90-day period in N. davidi males and females, based on survival, biochemical composition, body weight, carotenoid content and body coloration. Furthermore, histological and histochemical analyses of the male reproductive system were performed to evaluate the spermatophore quality. In all treatments, survival was >80%, and protein content was similar in both female and male shrimps. Lipid content was higher in females and males fed on a diet having the highest lipid level. Carotenoid content was higher and body coloration was brighter in females and males fed on a diet containing the highest carotenoid level. Histological and histochemical analyses of the spermatophore structure and composition showed no differences among diets, suggesting that the five commercial diets are adequate for satisfactory growth and spermatophore quality of N. davidi. The diverse sources and quantities of carotenoids in the highest carotenoid level diet render it more suitable for colour enhancement of this species.Fil: Tomas, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Sganga, Daniela Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Marciano, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: López Greco, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin
FIGURE 3 in Sexual dimorphism in a freshwater atyid shrimp (Decapoda: Caridea) with direct development: a geometric morphometrics approach
FIGURE 3. Relative deformations grids illustrating the variation in the mean shape of the carapace for (a) females and (b) males
Effects of European eel egg and larval stocking density on rearing water, offspring bacteriome and derived immune response
If human exploitation of the “critically endangered” European eel (Anguilla anguilla) is to continue, the eel's life cycle in captivity must be closed and techniques established to produce viable offspring in hatcheries. Despite stable offspring production, high mortality rates during early developmental stages have hindered progress in closing the lifecycle in captivity. We hypothesised that mortalities affecting embryos and newly hatched larvae, when the immune system is expected to play a vital role in protecting the offspring, could be linked to adverse microbial conditions arising in high-density rearing. We therefore set out to explore the bacteriome changes in rearing water and offspring as well as the molecular immunologic development of offspring at different initial stocking densities (500, 1000, 2000, and 4000 eggs/L) from fertilisation to 3 days post-hatch (dph). The lowest density resulted in ~5% higher survival. Independent of density, most mortality (~75%) occurred during embryonic rather than larval development. The bacteriomes of both offspring and rearing water differed according to stocking density, with a potentially healthier bacteriome at the lowest density, marked by greater ASV richness and abundance from various phyla (Proteobacteria, Actinobacteria, Fusobacteria, and Firmicutes). In contrast, the bacteriome of the highest density was dominated by Proteobacteria ASVs, including the potentially harmful Vibrionales order. We observed stage-specific bacteriome changes in offspring, transitioning from an inherent and balanced bacteriome in unadulterated eggs to a dominance of rapid-growing opportunistic bacteria in embryos (48 hpf), and finally to a more diverse bacterial community in larvae (3 dph). Thus, host-microbe interactions appear to significantly impact the overall high mortality observed during embryonic development. As the expression of stress and immune related genes was not affected by density, it seems that the molecular immune system was incapable of handling microbial interference during these early stages, aggravating the challenges faced during hatchery production. We conclude that low-density (500 eggs/L) incubation is a valid strategy to improve survival. However, high stocking densities (up to 4000 eggs/L) might be an acceptable compromise allowing more efficient utilisation of infrastructure and labour. At 4000 eggs/L, survival was reduced by only ~5%, while there was no effect on hatching success and no cellular stress response. Nevertheless, bacterial community management tools should be in place during high-density incubation to avoid r-selection and thus counter bacteria-associated mortality