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Author Contributions: Conceptualization, L.M.C. and P.P.; methodology, D.C., L.D.-F., J.F. and E.M.-A.; software, D.C. and L.D.-F.; validation, J.F. and J.B.; formal analysis, D.C., J.F. and P.E.H.; investigation, D.C., L.D.-F., J.F. and E.M.-A.; resources, J.B., P.P. and L.M.C.; data curation, E.M.- A.; writing—original draft preparation, D.C.; writing—review and editing, L.M.C., P.P. and P.E.H.; visualization, D.C., J.F., P.E.H. and E.M.-A.; supervision, L.M.C. and P.P.; project administration, L.M.C. and J.B.; funding acquisition, L.M.C. and J.B. All authors have read and agreed to the published version of the manuscript., Aquaculture plays a crucial role in meeting the increasing global demand for food and protein sources. However, its expansion is followed by increasing challenges, such as infectious disease outbreaks and antibiotic misuse. The present study focuses on the genetic and functional analyses of two Lacticaseibacillus paracasei (BF3 and RT4) and two Lactiplantibacillus plantarum (BF12 and WT12) strains isolated from a rotifer cultivation tank used for turbot larviculture. Whole-genome sequencing (WGS) and bioinformatics analyses confirmed their probiotic potential, the absence of transferable antibiotic resistance genes, and the absence of virulence and pathogenicity factors. Bacteriocin mining identified a gene cluster encoding six plantaricins, suggesting their role in the antimicrobial activity exerted by these strains. In vitro cell-free protein synthesis (IV-CFPS) analyses was used to evaluate the expression of the plantaricin genes. The in vitro-synthesized class IIb (two-peptide bacteriocins) plantaricin E/F (PlnE/F) exerted antimicrobial activity against three indicator microorganisms, including the well-known ichthyopathogen Lactococcus garvieae. Furthermore, MALDI-TOF MS on colonies detected the presence of a major peptide that matches the dimeric form of plantaricins E (PlnE) and F (PlnF). This study emphasizes the importance of genome sequencing and bioinformatic analysis for evaluating aquaculture probiotic candidates. Moreover, it provides valuable insights into their genetic features and antimicrobial mechanisms, paving the way for their application as probiotics in larviculture, which is a major bottleneck in aquaculture., Ministerio de Ciencia, Innovación y Universidades (España), Sección Dptal. de Nutrición y Ciencia de los Alimentos (Veterinaria), Fac. de Veterinaria, TRUE, pub

This study aimed to estimate the efficacy of two pike-perch juvenile production technologies: exclusive Recirculating Aquaculture System (RAS) culture (the RAS group) and pond larviculture with a transfer to the RAS at the 42nd day post-hatch (DPH). Both direct weaning on dry feed (the Pond-D group) and 10-day gradual weaning using bloodworms (the Pond-B group) after transfer to the RAS were evaluated in pond-nursed fry. Their survival and morphometric indices were monitored after the RAS habituation period (first 10 days), after the 18-day post-habituation period and after an additional 30 days of on-grow. Our results indicate a negative allometric growth of the pond-nursed fish during the nursing period, which was slower (p < 0.0001) in comparison to the RAS-nursed fry (16.3 ± 0.4 vs. 17.8 ± 0.7%/day). After transfer, these fish grew faster than the RAS-nursed fry (7.7 ± 0.1, 4.9 ± 0.5 and 6.1 ± 0.6 during habituation, 8.5 ± 0.6, 9.3 ± 0.5 and 6.7 ± 0.1%/day during post-habituation period, in the Pond-B, Pond-D and RAS groups, respectively). However, four weeks afterwards, the RAS-nursed fry were again superior in terms of growth (4.0 ± 0.1, 3.6 ± 0.2 and 4.6 ± 0.2%/day, for the Pond-B, Pond-D and RAS groups, respectively), and this was accompanied by a significantly lower feed conversion ratio in this group. Although the survival of the RAS-nursed fry during the nursing period was lower in comparison to the pond-reared fry (11.3 vs. 67.3%), the RAS seems to provide a long-term growth advantage.

Enrichment is the process of increasing the quality or nutritional value of any substances, i.e., live feeds. The live feeds are essential for larval rearing of commercially critical aquatic organisms. Still, the significant constraint noticed in the live feed sector is that sometimes they lack vital nutrients such as EPA, DHA, etc. Enrichment with crucial nutrients can improve larval survivability during early larval stages, which is the major bottleneck observed during larvi culture techniques in aqua hatcheries. Simultaneously various live feed such as Rotifers, Cyclops, copepod, Cladocerans, and Artemia are widely used as a carrier for bio encapsulation process in aquaculture. Numerous substances, especially essential amino acids, fatty acids, attractants, vitamin-mineral premix, are widely used for bio encapsulation in live feed culture units. Live feed brings those substances into their body either by feeding or osmoregulation. The main idea behind this article is to demonstrate the proper encapsulation method for various live feeds in aqua hatcheries.

Mussel culture in Europe is currently suffering from mass mortality events with mortality rates up to 100%. Vibrios belonging to the Splendidus clade have recently been implicated in these events. In this study, we demonstrate that V. tasmaniensis LGP32 and V. crassostreae J2-9, two model pathogens of oysters, are also pathogenic to blue mussel larvae in an immersion challenge test. After five days, LGP32 and J2-9 had killed 93 and 73% of challenged mussel larvae, respectively. Because quorum sensing, bacterial cell-to-cell communication with small signal molecules, has been demonstrated to control the virulence of various vibrios, we further investigated whether it had an impact on the virulence of V. tasmaniensis and V. crassostreae. We identified the components of a multichannel quorum sensing system (as also found in many other vibrios) in the genomes of both species. Knock out of selected components of this pathway revealed that in general quorum sensing in V. tasmaniensis LGP32 and V. crassostreae J2-9 has no impact on motility, protease activity, biofilm formation and virulence towards mussel larvae. Finally, the quorum sensing inhibitor cinnamaldehyde did not protect mussel larvae from these pathogens. Together, these data indicate that the multichannel quorum sensing systems of V. tasmaniensis LGP32 and V. crassostreae J2-9 have no impact on virulence of the bacteria towards blue mussel larvae. Hence, quorum sensing controlling virulence is not a general feature in vibrios as it has different outcomes on virulence in different species.

The wild abundance of Longfin smelt (Spirinchus thaleichthys, LFS) in the San Francisco Estuary (SFE) has declined to less than 1% of pre-1980’s numbers. As a result, they have been listed as “threatened” under the California Endangered Species Act since 2009. In an effort to avoid localized species extinction, a captive culture program was created for LFS through the Fish Conservation Culture Laboratory at the University of California, Davis. Larviculture methods for LFS are still being optimized to ensure a successful culture program. For my MS thesis, I tested the impacts of rearing temperature on early post-hatch LFS larvae from three different parental clutches to identify which rearing temperatures are best for successful development of these early life stages. I reared newly fertilized embryos and post-hatch, non-feeding yolk-sac larvae in freshwater (0 ppt) at 10, 12, or 15°C until 3 days post-hatch (dph). I measured larval morphometrics (total length, eye diameter, yolk sac area), and mortality for all groups. I was the first to evaluate the incidence and severity of jaw and spinal malformations for cultured LFS. Larvae reared at 15°C were smaller (mean ± SE; 0.52 ± 0.0040 mm), significantly younger at hatch (13.1 ± 0.1 days post-fertilization; dpf), and had slightly higher mortality and increased spinal malformations compared to other rearing temperatures. Embryos reared at 10 and 12°C were of similar size (10℃: 0.59 ± 0.0030 mm, 12℃: 0.56 ± 0.0030 mm), but 10°C larvae were significantly older at hatch (10℃: 18.4 ± 0.05 dpf, 12℃: 15.8 ± 0.1 dpf). Clutch had a much more variable impact on response metrics, markedly in size, suggesting that parentage may mediate developmental responses to unfavorable environmental conditions and change. No incidences of jaw malformation and a very small percentage of spinal malformations were observed amongst all treatment groups. Overall, the novel results described in this study suggest that parentage modifies the impacts

Ex-situ conservation, which is important to protect critically endangered species, requires special artificial breeding and rearing techniques during the early life stages of a species. This study describes the artificial breeding and larval rearing techniques to conserve ayu (Plecoglossus altivelis), an important fish that is endangered in some locations. Fish eggs and milt were acquired from mature fish by gently pressing the fish abdomen; subsequently, artificial insemination was performed by gentle mixing. The fertilized eggs were then incubated in running freshwater (for approximately 14 days). After hatching, the larvae were placed in brackish water (ca. 10‰ salinity; 7-8 mg L-1 dissolved oxygen) to maintain live food to the larvae. From the 1st to 35th day after hatching (DAH), the larvae were fed with live rotifers. Subsequently, from the 15th DAH onwards, the larvae were fed with brine shrimp nauplii along with rotifers and were familiarized with artificial food. After the fish gained a body length of 4-5 cm and started consuming 0.5-0.8 mm formulated food grain, they were transferred to a fingerling nursery with freshwater for further cultivation. This study also noticed that the susceptible stages of ayu larvae were at approximately 14-16th and 40-45th DAH. This work provides necessary information to design a conservation plan for the ayu population in the southern distribution range of this species where it is currently facing threats of extinction, such as in Vietnam. Additionally, the study describes the rotifer culturing technique that can assist in conducting larviculture., AACL Bioflux, 15(6), pp.2763-2774; 2022

Barramundi, the Asian sea bass (Lates calcarifer Bloch 1790), is a valuable aquaculture commodity, but seed survival is generally low. This study used a completely randomized design (two factors; 16 treatments; 3 replicates) to examine the effect of adding vitamin B complex and phosphorus to the rearing media on the survival, stress resistance, and phosphorus content of barramundi larvae. Barramundi larvae aged two days were stocked at a density of 25 fish L-1 in 40 L green plastic basins (30 L water) and reared for 30 days with natural feed (Chlorella and rotifers). The factor I was vitamin B complex with 4 levels: 0, 75, 150, and 225 mg L-1. Factor II was phosphorus with four levels: 0, 0.5, 1.0, and 1.5 mg L-1. Commercially available B vitamin complex and phosphorus mineral supplements were dissolved in water and added to the larval-rearing media. Analysis of variance showed that the combination of vitamin B complex and phosphorus treatments had a significant effect (P < 0.01) on survival, stress resistance, and phosphorus uptake. Survival and phosphorus content in barramundi larvae were highest with a combination of 150 mg L-1 vitamin B complex and 1.0 mg L-1 phosphorus and lowest in control (0 mg L-1 of both additives).

Insects are an important source of proteins, vitamins, amino acids, minerals, and lipids. In this context, the present study evaluated the essential fatty acid profileof the larval oilof Rhynchophorus palmarum(Coleoptera: Curculionidae) subjected to three plant tissue diets: Mauritia flexuosa(Arecaceae), Oenocarpus bataua(Arecaceae),and Jacaratia digitata(Caricaceae). Five adult individuals, 2 males,and 3 femaleswere captured for their reproduction in captivity. The hatched larvae were subjected to the three diets for 45 days. After this period, extraction was carried out and the fatty acid profile of the oil was determined. Being oleic monounsaturated fatty acid (18:1) and palmitic saturated fatty acid (16:0), which are found in greater abundance for the three diets. Regarding essentialfatty acids, linoleic (18:2) and alpha-linolenic (18:3) fatty acids were detected in concentrations of 1.96 ± 0.028 and 1.14± 0.007%, for the diet of Mauritia flexuosa, 0.67 ± 0.007 and 0.43 ± 0.035%, for the diet of Oenocarpus bataua, and 0.76 ± 0.000 and0.29 ± 0.007%, for the diet of Jacaratia digitata, respectively. The results show that diets influence the type of fatty acidmetabolized and its concentration. The larva is a source of monounsaturated fatty acids such as oleic (omega 9) and palmitoleic(omega 7)and of the essential fatty acids linoleic and alpha-linolenic precursors of the fatty acids of the omega 6 and omega 3 families., Los insectos son fuente importante de proteínas, vitaminas, aminoácidos, minerales y lípidos. Enese contexto el presente estudio,evaluóel perfil de ácidos grasos esenciales del aceite de larva deRhynchophoruspalmarum(Coleoptera:Curculionidae)sometida a tres dietas de tejidos vegetales:Mauritiaflexuosa(Arecaceae), Oenocarpusbataua(Arecaceae)y Jacaratia digitata(Caricaceae).Fueroncapturados cinco individuos adultos, 2 machos y 3 hembraspara sureproducción en cautiverio.Las larvas eclosionadas sesometieron a las tres dietas por45 días.Después de este periodose efectuó la extracción y se determinó elperfil deácidos grasosdel aceite.Siendoel ácido graso monoinsaturado oleico(18:1)y el ácido graso saturado palmítico(16:0),losqueseencuentran en mayor abundanciapara las tres dietas. Respectoalos ácidos grasos esenciales,fuerondetectadoslosácidosgrasoslinoleico(18:2)y alpha linolénico(18:3)enconcentracionesde1,96±0,028y1,14±0,007%,parala dieta deMauritia flexuosa,0,67±0,007y0,43±0,035%,paraladietadeOenocarpusbataua,y0,76±0,000y0,29±0,007%,paraladietadeJacaratia digitata,respectivamente.Losresultados muestran que las dietas influyen en el tipo de ácido graso metabolizado y su concentración.Lalarva es fuente de ácidos grasos monoinsaturados como el oleico (omega 9) y el palmitoleico(omega 7), y de los ácidos grasos esenciales linoleicoy alpha linolénico precursores de los ácidos grasos de la familia omega 6 y omega 3.

Sea cucumber Holothuria nobilis is an economically important species for livelihoods in many countries. However, an increase in demand for this species has led to the depletion of wild stocks. The introduction of this species in aquaculture is necessary to reduce fishing pressure. This study was taken to establish breeding and larval rearing techniques for the development of H. nobilis aquaculture. The broodstock collected from the wild were induced to spawn by using thermal stimulation and the combination of thermal and algal stimulation methods. The larvae obtained from induced spawning were reared using different diets (mixed microalgae and mixed microalgae with artificial feeds) at different stocking densities (300, 600, and 1000 larvae/l). Thermal stimulation is the best method of inducing spawning to H. nobilis yielding up to 1,300,000 fertilized eggs. The highest survival rate (27.5%) of doliolaria larvae was achieved using a mixed microalgae diet. The highest survival rate of doliolaria larvae (41.5 %), growth, and development were in the stocking density of 600 larvae/l.

The target of this study was to use indigenous probiotic bacteria in the rearing of seabass larvae. A Phaeobacter sp. strain isolated from bonito yolk-sac larvae (Sarda sarda) and identified by amplification of 16S rDNA showed in vitro inhibition against Vibrio anguillarum. This Phaeobacter sp. strain was used in the rearing of seabass larvae (Dicentrarchus labrax L.) in a large-scale trial. The survival of seabass after 60 days of rearing and the specific growth rate at the late exponential growth phase were significantly higher in the treatment receiving probiotics (p < 0.05). Microbial community richness as determined by denaturing gradient gel electrophoresis (DGGE) showed an increase in bacterial diversity with fish development. Changes associated with the administration of probiotics were observed 11 and 18 days after hatching but were not apparent after probiotic administration stopped. In a small challenge experiment, seabass larvae from probiotic treatment showed increased survival (p < 0.05) after experimental infection with a mild pathogen (Vibrio harveyi). Overall, our results showed that the use of an indigenous probiotic strain had a beneficial impact on larval rearing in industry-like conditions.

Prochilodus mariae (bocachico llanero or coporo) is amongst the most important fish in the Meta River (a major left tributary of the Orinoco River); along with being the largest of the Prochilodus species in the river basin, flannel-mouth characiforms contribute greatly to the dynamics of the region’s food chain and fisheries. This work was aimed at assessing Prochilodus mariae post-larvae feeding habits during their first thirty days of exogenous feeding until the beginning of the alevin stage. Simulations were made in the Instituto de Acuicultura de los Llanos (IALL) facilities’ earthen fish ponds to closely resemble the fishes’ natural annual water and feeding conditions. The ponds had been organically fertilised with cattle manure and hay and were then periodically inundated and drained to simulate the Meta River’s tributaries natural/annual floodplains or areas that are periodically inundated by high water levels. The ponds were stocked with larvae obtained by artificial spawning at twenty larvae/m2 density when around 80% of their yolk sacs had been absorbed. Post-larvae and pond water samples containing zooplankton and phytoplankton were collected at 8 am every other day for 30 days and fixed in 4% buffered formalin. Seven post-larvae/pond stomach/gut contents (frequency of fullness index - FI) were analysed from 156 specimens divided into size intervals ranging from 6-8.99, 9-17.99, 18-26.99, 27-35.99, 36-44.99 and 45-47.99 mm in length. Food items’ frequency of abundance (i.e. supply) in the pond water and periphyton were estimated. First-size interval post-larvae explore periphyton-related organisms for their food source (mainly bacteria, protozoans and algae). This first sampling was characterised by 66.7% of the post-larvae having empty stomachs. Second-size interval post-larvae FI tended reflect the consumption of pelagic organisms, having a preference for microcrustaceans (cladocerans and copepods). The longest alevins (45-47.99 mm long) started consum, Entre os peixes mais importantes do rio Meta encontra-se Prochilodus mariae (bocachico llanero ou coporo), devido a ser dos maiores bocachicos da bacia, assim como a sua contribuição para a biomassa trófica e pesca da região. O presente trabalho pretende avaliar a dieta das pós-larvas do coporo Prochilodus mariae, até ao início da fase de alevinos em condições simuladas durante os primeiros trinta dias de alimentação exógena. Os estanques do IALL destinados ao desenvolvimento deste trabalho, foram fertilizados organicamente com (esterco bovino e feno) atendendo às condições que ocorrem a cada ano, na entrada de água nas áreas de alagamento dos afluentes, que foram semeados com larvas obtidas por reprodução induzida na densidade de vinte larvas / m2 e com 80% do saco vitelino absorvido. A cada dois dias, durante 30 dias, às 8:00 da manhã, as pós-larvas eram recolhidas juntamente com a água, e fixadas em formalina tamponada a 4%. Foram avaliados os índices de frequência (IF) do conteúdo estomacal de sete pós-larvas/tanque e itens alimentares encontrados nas águas e perifiton. As análises foram realizadas com um total de 156 espécimes entre 6-8,99; 9-17,99; 18-26,99; 27-35:99; 36-44,99; 45-47,99mm de comprimento total. As pós-larvas do primeiro intervalo exploram organismos relacionados com o perifiton principalmente bactérias, protozoários e algas, esta primeira amostragem foi caracterizada porque 66,7% das pós-larvas apresentavam estômagos vazios. Nas pós-larvas do segundo intervalo o IF do conteúdo estomacal mostrou uma tendência para o consumo de organismos pelágicos com preferência pelos cladóceros. No último intervalo, os alevinos começam a consumir detritos (partículas orgânicas, bactérias, fungos) e formas de fitoplâncton ligadas às superfícies do substrato (feno) e ao fundo do tanque., Entre los más importantes peces del río Meta se encuentra Prochilodus mariae (bocachico llanero o coporo), tanto por su mayor tamaño dentro de los bocachicos de la cuenca, como por su aporte a la biomasa trófica y de las pesquerías de la región. En el presente trabajo se evaluó el régimen alimenticio de poslarvas (inicio de la alimentación exógena) del coporo Prochilodus mariae, hasta el inicio de la fase de alevino (aletas completas y cuerpo con escamas), en condiciones simuladas durante los primeros 30 días de alimentación exógena. Los estanques en tierra del IALL, asignados para el desarrollo de este trabajo, fueron abonados orgánicamente con (bovinaza y heno) teniendo en cuenta las condiciones que suceden cada año, a las entradas de aguas en las áreas de inundación de los afluentes, los que fueron sembrados con larvas obtenidas por reproducción inducida a densidad de veinte larvas / m2 y con el 80% de su saco vitelino absorbido. Cada dos días, durante 30 días, a las 8:00 h, fueron colectadas poslarvas junto con las muestras de zooplantcton y fitoplancton y fijados en formol bufferado al 4%. Los índices de frecuencia (IF) de los contenidos estomacales de siete poslarvas/estanque y los ítems alimenticios como oferta hallados en aguas y perifiton fueron evaluados. Los análisis se realizaron con un total de 156 ejemplares que oscilan entre intervalos de 6-8.99; 9-17.99; 18-26.99; 27-35.99; 36-44.99; 45-47.99 mm de longitud total. Las poslarvas del primer intervalo exploran organismos relacionados con el perifiton principalmente bacterias, protozoos y algas en este primer muestreo se caracterizó porque el 66.7% de las poslarvas presentaron estómagos vacíos. En las poslarvas del segundo intervalo el IF de los contenidos mostró una tendencia por el consumo de organismos pelágicos con preferencia por los cladóceros. En el último intervalo los alevinos inician el consumo de detritos (materia orgánica particulada, bacterias, hongos) y otras formas del fitoplancton cercano

The design of specific feed based on digestive physiology, and an adequate feeding schedule, are important to reduce cannibalism and increase survival rate in larvae fish. The first objective of this study was evaluating growth, survival and cannibalism during tropical gar (Atractosteus tropicus Gill) larviculture, using four feeding schedules: CT (10 day co-feeding of Artemia nauplii and commercial trout feed), T1 (commercial trout feed), T2 (10 day co-feeding of Artemia nauplii and A. tropicus larvae designed feed) and T3 (A. tropicus larvae designed feed). The second objective was to determinate correlation between survival and cannibalism, using a linear regression model. We observed better growth and survival in the co-feeding treatments CT and T2. Cannibalism was observed in all treatments, with higher presence in T1 and T3 (treatments without Artemia nauplii co-feeding). It was observed a strong correlation between survival and cannibalism (r = -0.88, p < 0.05), demonstrating that cannibalism has a considerable effect on survival rate. We concluded that T2 represent the best alternative for A. tropicus feeding during larviculture, since they present better growth and less cannibalism., El diseño de dietas con base en la fisiología digestiva, así como un adecuado esquema de alimentación, permiten la disminución del canibalismo y el incremento de la supervivencia en la etapa larvaria de peces. Por lo anterior, el objetivo fue evaluar el crecimiento, supervivencia y canibalismo en la larvicultura del pejelagarto (Atractosteus tropicus Gill) bajo cuatro esquemas de alimentación: CT (co-alimentación con nauplio de Artemia por 10 días y dieta comercial de trucha), T1 (alimentación con la dieta comercial de trucha desde la apertura de la boca), T2 (co-alimentación con nauplio de Artemia y dieta diseñada para larvas de A. tropicus por 10 días) y T3 (alimentación con la dieta diseñada para A. tropicus desde la apertura de la boca), así como determinar la correlación entre el canibalismo y la supervivencia mediante un modelo de regresión lineal. Los mejores crecimientos y supervivencias se obtuvieron en los tratamientos T2 y CT. En todos los tratamientos se presentó canibalismo, siendo más alto cuando no se co-alimentó con nauplio de Artemia (T1 y T3). Se encontró una fuerte correlación (r = -0.88, p < 0.05) entre la supervivencia y el canibalismo, lo que demuestra que el canibalismo tiene efecto sobre la supervivencia. El tratamiento T2 representa la mejor alternativa para la larvicultura de A. tropicus, con mayor crecimiento y menor canibalismo.

We review a recent progress of photophysiological studies in the rotifer Brachionus plicatilis species complex. The rotifers have a light sensor i.e., eyespot inducing phototactic behavior. For the rotifer B. plicatilis sp. complex, the eyespot efficiently absorbs the light wavelength ranging from 450 to 550?nm. The function of eyespot is affected by diet species from 30-day batch cultures fed by either microalgae Nannochloropsis oculata or baker's yeast Saccharomyces cerevisiae. By feeding baker's yeast, rotifer eyespot gradually lost its function: area (5.5 times) and absorbance (2.2 times) decrease compared to those fed by N. oculata. Phototactic behavior and reproductive characteristics of the rotifer B. plicatilis sp. complex varied with different light wavelengths and intensities. The rotifers show light wavelength dependent phototaxis associated with the reception of an eyespot. For the phototactic behavior in horizontal level, light intensity is also a significant factor to regulate phototaxis. The rotifers show strong positive phototaxis under blue (peaks at 470?nm), green (525?nm), and white (460 and 570?nm) lights at 0.5?W/m2. Rotifer reproduction is also affected by light wavelength and intensities. Asexual reproduction of rotifers is accelerated by green and red lights at 0.5?W/m2. On the other hand, active sexual reproduction is observed with blue light at 1.4?W/m2. Under a certain light condition inducing active phototactic behavior, the rotifers show continuous swimming movement without attaching to substrates. The different behaviors associated with light conditions affect the reproductive characteristics of rotifers. The regulation of live food distribution is significant for feeding efficiency of fish larvae. The efficient feeding promotes larval growth and survival: hence it is a significant factor for successful larviculture. Fish larvae also show different phototactic behavior related to light wavelengths and intensities. Therefore, the distrib, Aquaculture, 497, pp.253-259; 2018

Temperature and light are important factors affecting production in the aquaculture industry, as they can drive behaviour and physiological responses of free‐swimming larval stages. However, the influence of light on crustacean farming has received little consideration. The common spider crab Maja brachydactyla Balss, 1922 has a great potential for aquaculture because of the easy maintenance, high fecundity, and short larval development. In order to optimize larval culture techniques, we quantified the influence of temperature and light on larval survival, development, and elemental (carbon and nitrogen) body composition. Constant darkness resulted in longer developmental time as compared with daily light photoperiod (6–16 light hours). Larvae reared under constant darkness showed also reduced dry mass, carbon and nitrogen content, and C:N ratio. We also found carry‐over effects of light conditions: constant darkness experienced during the zoeal stage led to increased developmental time in the megalopa stage. Temperature and light showed additive effects. We optimized the larval culture of M. brachydactyla requiring around 14 days from hatch to first juvenile by keeping cultures under 21 ± 1°C and light sources simulating the daily light cycle

The osteological development of the vertebral column and the caudal complex of the clownfish Amphiprion ocellaris, an important ornamental species is described. The organisms were reared under controlled conditions from hatching until 30 days post hatch (DPH) and methods for the clearing and differential staining of bone and cartilage tissues were applied. At hatching time, most of the vertebral elements had developed in cartilage stage and the notochord in pre-flexion larvae; 11 neural arches were located in the abdominal region while 12 neural arches and 12 haemal arches were found in the caudal region. In the caudal complex, the hypurals were still separated from one another. On 6 DPH the notochord was in flexion stage and the ventral ribs were observed, while 12 neural spines and 12 haemal spines had developed in the caudal region and the hypurals were fused. The notochord was in the post-flexion stage on 11 DPH and the complex caudal completely formed with all the neural spines and haemal spines fully developed. At 23 DPH all structures had ossified. The vertebral column was divided in the abdominal region and comprised of 11 vertebrae while in the caudal region there were 15 vertebrae including the urostyle. Detailed information of osteological structures serve as a reference for the timely detection of malformations during clownfish aquaculture., Se describe el desarrollo osteológico de la columna vertebral y del complejo caudal de Amphiprion ocellaris, una especie de importancia ornamental. Los organismos se cultivaron bajo condiciones controladas desde la eclosión hasta los 30 días después de eclosionar (DDE) y fueron procesados con los métodos de clareado y tinción diferencial de tejidos óseos y cartilaginosos. Las larvas al eclosionar ya tienen desarrollados la mayoría de sus elementos vertebrales en etapa de cartílago y el notocordio en estado de pre-flexión; la región abdominal presenta 11 arcos neurales y en la región caudal 12 arcos neurales y 12 arcos hemales. En el complejo caudal se observaron los hipurales aún separados entre ellos. A los 6 DDE el notocordio se encontró en etapa de flexión y aparecen las costillas ventrales, y en la región caudal se desarrollaron 12 espinas neurales y 12 espinas hemales y los hipurales ya se han fusionados. A los 11 DDE el notocordio ya estaba en pos-flexión y el complejo caudal completamente formado, y se desarrollaron completamente todas las espinas neurales y espinas hemales. A los 23 DDE se observó la osificación de todas las estructuras. La columna vertebral de A. ocellaris se divide en una región abdominal, con 11 vértebras y una región caudal con 15 vértebras incluyendo el urostilo. El conocimiento detallado de las estructuras osteológicas servirá de referencia para la detección oportuna de malformaciones durante el cultivo del pez payaso.

Ingestion of bacteria at early stages results in establishment of a primary intestinal microbiota which likely undergoes several stages along fish life. The role of this intestinal microbiota regulating body functions is crucial for larval development. Probiotics have been proved to modulate this microbiota and exert antagonistic effects against fish pathogens. In the present study, we aimed to determine bacterial diversity along different developmental stages of farmed Senegalese sole (Solea senegalensis) after feeding probiotic (Shewanella putrefaciens Pdp11) supplemented diet for a short period (10–30 days after hatching, DAH). Intestinal lumen contents of sole larvae fed control and probiotic diets were collected at 23, 56, 87, and 119 DAH and DNA was amplified using 16S rDNA bacterial domain-specific primers. Amplicons obtained were separated by denaturing gradient gel electrophoresis (DGGE), cloned, and resulting sequences compared to sequences in GenBank. Results suggest that Shewanella putrefaciens Pdp11 induces a modulation of the dominant bacterial taxa of the intestinal microbiota from 23 DAH. DGGE patterns of larvae fed the probiotic diet showed a core of bands related to Lactobacillus helveticus, Pseudomonas acephalitica, Vibrio parahaemolyticus,and Shewanella genus, together with increased Vibri o genus presence. In addition, decreased number of clones related to Photobacterium damselae subsp piscicida at 23 and 56 DAH was observed in probiotic-fed larvae. A band corresponding to Shewanella putrefaciens Pdp11 was sequenced as predominant from 23 to 119 DAH samples, confirming the colonization by the probiotics. Microbiota modulation obtained via probiotics addition emerges as an effective tool to improve Solea senegalensis larviculture.

Suitable nutrition at first feeding in marine fish larvae is an important factor for successful larval and juvenile rearing. In this way probiotic supplementation may contribute to better face the habitual stress of metamorphosis and weaning at early sole stages. The aimof this study was to optimize Shewanella putrefaciens Pdp11 administration to Senegalese sole (Solea senegalensis) at early stages of development. For this purpose, we studied the influence of a short pulse of S. putrefaciens Pdp11 (10–30 dah) on growth performance, gut microbiota modulation, digestive enzymes activities and body composition. These probiotic bacteria were incorporated using Artemia as live vector (2.5 × 10 7 cfu mL −1 ) and supplied to sole specimens in a co-feeding regime (Gemma, Skretting) by triplicate. S. putrefaciens Pdp11 colonized larval gut being present from23 to 119 dah. Probiotic supply significantly modulated larval and fry gut microbiota. A PCA analysis including all the parameters analyzed strongly associated S. putrefaciens Pdp11 presence with a higher fish growth, a higher digestive proteolytic activity level and a fish body composition modulation along S. senegalensis rearing. In addition less size variability was obtained frommetamorphosis until the end of weaning. In conclusion a short pulse of S. putrefaciens Pdp11 (10– 30 dah) seems sufficient to obtain a suitable microbial modulation involved in a better growth performance and body composition that suggests a great potential for sole aquaculture production.

Probiotic supplementation in fish aquaculture has significantly increased in the last decade due to its beneficial effect on fish performance. Probiotic use at early stages of fish development may contribute to better face metamorphosis and weaning stress. In the present work, we studied the influence of Shewanella putrefaciensPdp11 supplementation on growth, body composition and gut microbiota in Senegalese sole (Solea senegalensis) during larval and weaning development.S. putrefaciensPdp11 was incorporated usingArtemiaas live vector (2.5910 7 cfu mL -1 ) and supplied to sole specimens in a co-feeding regime (10–86 DAH) by triplicate. Probiotic addition promoted early metamorphosis and a significantly higher growth in length at 24 DAH larvae.S. putrefaciens Pdp11 also modulated gut microbiota and significantly increased protein content and DHA/EPA ratios in sole fry (90 DAH). This nutritional enhancement is considered especially important after weaning, where significantly higher growth in length and weight was observed in probiotic fish. Moreover, a less heterogeneous fish size in length was detected since metamorphosis till the end of weaning, being of interest for sole aquaculture production. After weaning, fish showed significantly higher growth (length and weight) and less variable lengths in fish when supplemented with probiotics. Both the enhancement of nutritional condition and the decrease in size variability associated with probiotic addition are highly interesting for sole aquaculture production.

Zooplankton is a very important source of natural food for larvae of many aquaculture species. In semi-intensive systems, which are the dominant type of carp production, many fish species feed on both zooplankton and zoobenthos as adults, while larvae and fry rely mostly on zooplankton. It provides them with high quality nutrients and other molecules such as proteolitic enzymes, hormones and growth factors, which support digestive processes in immature larval gut. Larviculture, especially start feeding of early larval stages, appear to be a critical point in fish culturing. However, artificial diets formulated for larvae show poor digestibility. Use of live feed of small dimensions, good nutritive characteristics and locomotion that provides visual stimulus, overcome that problem. Zooplankters commonly used for mass production as live feed for fish larvae are Rotifers (Brachionus plicatilis and B. calyciflorus) and brine shrimp (Artemia salina). Shortly after hatching, carp larvae are transferred to nursing ponds for further rearing. Ponds are previously prepared through agrotechnical measures in order to provide nutrient enrichment and stimulate production. During the first days of exogenous feeding, larvae consume only the smallest zooplankters such as Rotifers and naupliar larvae of Copepods, while later they move on to bigger pray as Cladocerans. However, due to variable environmental conditions, predation, competition or infections in earthen ponds, mortality in nursing ponds is often very high, reaching over 90%. Thereby, modern approach suggests rearing in indoor tanks in controlled systems and use of automatic feeding systems to provide precise portions of zooplankton.

[POR] Foram comparados os efeitos de diferentes dietas e da transição alimentar sobre o desempenho zootécnico e a morfologia do trato digestório de larvas de pacu alimentadas com duas dietas comerciais e uma dieta experimental microencapsulada produzida por gelificação interna. Larvas com quatro dias de vida receberam os seguintes protocolos alimentares: somente náuplios de artêmia em quantidades crescentes (controle positivo); larvas mantidas em jejum (controle negativo); três tipos de alimento formulado durante todo o experimento (dieta experimental microencapsulada, dieta comercial NRD1.2/2.0, Inve, USA, e dieta Poli-Peixe 450F, PoliNutri, Brasil); e três protocolos de transição alimentar com náuplios de artêmia durante os seis primeiros dias, seis dias de coalimentação, e somente as respectivas dietas formuladas após esse período. O experimento foi conduzido por 23 dias em delineamento inteiramente casualizado, com avaliações periódicas do crescimento e do sistema digestório. A taxa de sobrevivência foi determinada ao final do experimento. Os melhores desempenhos de crescimento e sobrevivência, assim como mais acelerada organogênese do sistema digestório, foram verificados entre os animais que receberam alimento vivo. As larvas que passaram pela transição alimentar apresentaram médias intermediárias de crescimento e sobrevivência e não diferiram entre si. Entre os grupos que receberam apenas dieta inerte, somente naquele alimentado com a dieta nacional houve sobrevivência até o final do experimento. Nenhuma das dietas formuladas é adequada para uso como alimento exclusivo para larvas de pacu. Na fase de transição alimentar, a dieta experimental microencapsulada proporciona resultados de sobrevivência e crescimento semelhantes aos obtidos com dietas comerciais. © 2012 Sociedade Brasileira de Zootecnia., [EN] The effects of different diets and dietary transition on the performance and morphology of the digestive tract of pacu larvae fed two commercial formulated diets and an experimental microencapsulated diet produced by internal gelation were evaluated. Four-day old pacu larvae received the following treatments: only artemia nauplii in increasing amount during the experiment (positive control); larvae maintained at fasting (negative control); three types of formulated diets throughout the experiment (experimental microencapsulated diet, commercial diet NRD1.2/2.0, Inve, USA, and diet Poli-Peixe 450F, PoliNutri, Brazil); and three weaning protocols in which artemia nauplii were given from the 1 st to 6 th days, six days of co-feeding (artemia nauplii + the respective formulated diet), and only respective diets formulated after this period. The experiment was conducted for 23 days in a completely randomized design, with periodical evaluations of growth and digestive system. Survival rate was determined at the end of the experiment. The best performances of growth and survival, as well as the organogenesis of the digestive tract, were verified for the animals which received live feed. The larvae at weaning treatments induced intermediate growth and survival, which did not differ statistically between them. Considering the treatments that received only formulated diets as first feed, the PoliNutri diet was the unique that showed alive larvae at the end of experiment. None of the formulated diets are adequate as initial exogenous food for pacu larvae. During the weaning, the microencapsulated experimental diet provides growth and survival performances similar to those obtained with the commercial diets. © 2012 Sociedade Brasileira de Zootecnia.

We reviewed research on the broodstock management and larviculture of the Pacific northern bluefin tuna (PBT) Thunnus orientalis in Japan. Japan has been at the forefront of PBT research since 1970 due to the participation by federal and prefectural governments and universities in a national project aimed to optimize productivity of the sea around Japan. In 1979, scientists at Kinki University succeeded in the first spontaneous spawning in captivity by the broodstock of 5 year-old PBT. Successful spawning was also performed in 1980 and 1982, but no spawning then occurred until 1993, when Maruha Nichiro Holdings, Inc. (MNH) and Nippon Formula Feed Manufacturing Company, Ltd. (NFFMC) became involved in tuna farming and succeeded in the spawning of four-year-old broodstock. Since then, successful spawning of PBT in captivity has been reported from several sites as well as spawning in Kinki Univ. since 1994. With the successful spawning of PBT, the Fisheries Research Agency (FRA; formerly, Japan Sea Farming Association) of Kinki University, in conjunction with MNH, NFFMC, and Takuyo Ltd., has actively carried out research on and development of tuna larviculture technology. Thus, knowledge about broodstock management and larviculture has accumulated in Japan, but technical problems with larviculture still remain to be solved. There are 9 sites of successful spawning in net pens in Japan so far. At 4 of these sites in regions around Amami Island, yearly spawning has stably occurred. We have been accumulating data about the period of maturation, environmental key factors triggering the spawning, the age of onset of spawning, and the pattern of spawning through measurement of the ambient environment, gonad morphometry, endocrinology, mitochondrial DNA analysis, and daily careful observation of broodstock. Research on PBT larviculture at Kinki University, FRA, MNH, NFFMC, and Takuyo have succeeded in producing tens of thousands of hatchery-raised juveniles. As a result, Kink, Aquaculture, 315(1-2), pp.2-8; 2011

The increasing market demand for cephalopods and the experiences obtained with different species has boosted the interest in developing their culture in Latin America. In 2008, an international workshop was held in Puerto Montt, Chile, with 14 experts in experimental cephalopods aquaculture from Brazil, Chile, Spain and Mexico. Several topics were approach within the holobenthic species Octopus maya and the merobenthic species Enteroctopus megalocyathus, Octopus vulgaris and Robsonella fontaniana. Part of the conclusions demonstrated that the two greatest difficulties for their production were survival of paralarvae for merobenthic species, and survival of early juveniles for holobenthic species. Besides, there is a need to study the endogenous and exogenous factors affecting health and nutritional status of embryos, paralarvae and juveniles. These stages, which may limit the culture, should be extensively studied in order to develop the appropriate environmental conditions and culture systems for the physiological and behavioural requirements, from egg incubation up to juveniles to reach a grow-out phase.

At present, the production of merobenthic octopuses with a post-eclosion planktonic phase is a great challenge for global aquaculture. So far, juveniles from only four species have been reported to have been obtained under controlled rearing conditions: Octopus vulgaris, Octopus joubini, Enteroctopus dofleini and Robsonella fontaniana, the only Chilean species. Robsonella fontaniana (Orbigny, 1834) is a small-sized octopus traded in international markets as “baby octopus”. It is distributed over nearly the entire southern coast of South America, both in the Pacific and Atlantic coasts. This study shows new results regarding the biochemical characteristics in embryonic and paralarval stages, as well as the characteristics of food consumption during the paralarval stage that allow us to discuss a baseline on which to define a strategy for the larviculture of this species.

This study evaluated several predator-prey ratios on Dorada (Brycon sinuensis) larviculture. The onset of exogenous feeding using four predator-prey ratios 0:1 (T1), 1:1 (T2), 2:1 (T3) and 4:1 (T4) was studied. The preys used were newly hatched Bocachico (Prochilodus magdalenae) larvae, which were fed just once. The Dorada larvae were weighed and measured at the beginning and the end of the experiment. The variables measured were weight gain (Wg), length gain (Gl), specific growth rate (G), survival (S), stress resistance (Rs), natural mortality (Nm) and cannibalism mortality (Mc). The T4 had the highest Wg (3.9 ± 0.4 mg) and G (5.8 ± 0.4%/h). Survivability was increased when feeding two (T3 = 84.2%) and four forage larvae for each Dorada larvae (T4 = 86.7%). The lowest survivability was observed when no forage larvae were fed (T1 = 51.8%), coinciding with the greatest mortality from cannibalism (46.3%). The lowest mortality from cannibalism occurred when two (T3 = 12.7%) to four forage larvae per Dorada larvae (T4 = 12.0%) were offered. Natural mortality was low, ranging between 1.3% (T4) and 3.2% (T3) (p> 0.05). The test values of Rs ranged from 86.7 ± 10.3% (T1) and 95.0 ± 5.5% (T3) (p>0.05). These results indicate that offering between two and four forage larvae as first feeding to Dorada larvae reduces cannibalism and offers the best results for survival and growth during larviculture., O objetivo do estudo foi avaliar o efeito da densidade de presas na larvicultura de Dorada Brycon sinuensis, para o qual foram fornecidas, durante 24 horas, quatro diferente proporção presa-predador 0:1 (T1), 1:1 (T2), 2:1 (T3) e 4:1 (T4) ao inicio da alimentação exógena. Como presa foram utilizadas larvas recém eclodidas de Bocachico Prochilodus magdalenae, as cuais foram fornecidas por uma única vez. As larvas de Dorada foram pesadas e medidas ao inicio e final do experimento para calcular ganho de peso (Gp), ganho de comprimento (Gl) e taxa de crescimento específico (G); também foi calculada a supervivência (S), resistência ao estresse (Re), mortalidade natural (Mn) y mortalidade pelo canibalismo (Mc). Os maiores valores de Gp (3.9 ± 0.4 mg) e G (5.8 ± 0.4%/h) foram registradas no T4, apresentando diferença com os demais tratamentos (p<0.05); entanto que os maiores registros de Gl (2.0-2.4 mm) apresentaram se entre os tratamentos T2, T3 e T4 sem apresentar se diferença significativa entre estes (p>0.05); mas sim com relação a T1. Quando foi alimentado com duas (T3 = 84.2%) e quatro larvas forrageiras por cada larva de dorada (T4 = 86.7%) foram observadas as maiores supervivências; ainda que a menor obteve se quando não foram fornecidas larvas forrageiras (T1 = 51.8%); foi encontrado nesse tratamento a maior mortalidade pelo canibalismo (46.3%). Assim mesmo, as menores mortalidades por canibalismo apresentaram-se quando foram fornecidas entre duas (T3 = 12.7%) e quatro larvas forrageiras por cada larva de Dorada (T4 = 12.0%). A mortalidade natural foi baixa e oscilou entre 1.3% (T4) e 3.2% (T3) sem diferença significativa (p>0.05). Os valores do teste de Re estiveram entre 86.7 ± 10.3% (T1) e 95.0 ± 5.5% (T3) sem diferença significativa (p>0.05). Estes resultados indicam que fornecer entre duas e quatro larvas forrajeiras como primeira alimentação em larvas de Dorada diminui o canibalismo e oferece melhores resultados de supervivência e crescimento durante a larvi, El objetivo del estudio fue evaluar el efecto de la densidad de presas en la larvicultura de dorada Brycon sinuensis, para lo cual fueron ofrecidas, durante 24 horas, cuatro proporciones presa-predador 0:1 (T1), 1:1 (T2), 2:1 (T3) y 4:1 (T4) al inicio de la alimentación exógena. Como presa fueron utilizadas larvas recién eclosionadas de bocachico Prochilodus magdalenae, suministradas por una sola vez. Las larvas de dorada se pesaron y se midieron al inicio y al final del experimento para estimar ganancia en peso (Gp), ganancia en longitud (Gl) y tasa de crecimiento específico (G); también se calculó la sobrevivencia (S), resistencia al estrés (Re), mortalidad natural (Mn) y por canibalismo (Mc). Los mayores valores de Gp (3.9 ± 0.4 mg) y G se registraron en T4 (5.8 ± 0.4%/h), presentando diferencia significativa con los demás tratamientos (p<0.05); mientras que los mayores registros de Gl se presentaron en T2, T3 y T4 (2.0-2.4 mm), sin presentarse diferencia significativa entre estos tratamientos (p>0.05); pero si con relación a T1. Cuando se alimentó con dos (T3=84.2%) y cuatro larvas forrajeras por cada larva de dorada (T4=86.7%) se observaron las mayores sobrevivencias; mientras que la menor se obtuvo cuando no se suministraron larvas forrajeras (T1=51.8%); encontrándose en ese tratamiento la mayor mortalidad por canibalismo (46.3%). Asimismo, las menores mortalidades por canibalismo se presentaron cuando se ofrecieron entre dos (T3=12.7%) y cuatro larvas forrajeras por cada larva de dorada (T4=12.0%). La mortalidad natural fue baja y osciló entre 1.3% (T4) y 3.2% (T3) sin observarse diferencia significativa (p>0.05). Los valores de la prueba de Re oscilaron entre 86.7 ± 10.3% (T1) y 95.0 ± 5.5% (T3) sin observarse diferencia significativa (p>0.05). Estos resultados indican que suministrar entre dos y cuatro larvas forrajeras como primera alimentación en dorada reduce el canibalismo y ofrece mejores resultados de sobrevivencia y crecimiento durante la larvicultur

Changes in lipid class, fatty acid, fat-soluble vitamins, amino acid and minerals were studied during larval development of Maja brachydactyla Balss, 1922 in order to provide information of its ontogeny and evaluate possible dietary deficiencies and constraints. Four different batches were analyzed from hatching to metamorphosis using enriched Artemia as food. Cultured larvae were in a good nutritional condition as confirmed by the continuous lipid accumulation throughout ontogeny. A regulation of polyunsaturated fatty acids (PUFA) occurred during development in order to maintain adequate basal levels of x-3 fatty acids (likely through a 21 retro conversion of C20 and C22 into C18 PUFA). Variations in the tocopherol levels indicated its possible role in PUFA protection against oxidation. Essential aminoacid balance during development was not correlated with the Artemia feeding regime, but rather reflected inherent variations of the own species ontogeny. Larval requirements in essential minerals were fully supplied by the enriched Artemia.

One of the biggest problems that face the modern fish breeding is found in the phase of the larviculture, since a great number of the just born larvaes usually die at the moment of begin with their first feeding, the surveys carried out about this issue in native catfishes are scarces and specially for the Ramidia Sebae. In the Unity of Larviculture of the Aquiculture Institute de los Llanos (IALL), of the University de los Llanos (Villavicencio - Colombian City), were carried out four tests in april and may of the 2004 to assess the influence of the first feeding in the growth and surviving of the catfishs larvaes Rhamidia Sebae. The larvaes were obtained from wild individuals through induced reproduction with Extract of Hipofisis of Carpa (type of fish) (EHC). In each one of the four tests were tested three types of food along with a witness without feeding, each test was carried out three times. For each trial was developed a protocol: To 68 hours after the eclosion hpe (hpe means hours arfter/post eclosion). The larvaes were put in 5000 cm3 glass containers, with a density of 50 larvaes/1000cm3 (3000 cm3 used), with steady air cooling. 72 hpe the larvaes were put in four different groups; three of them were fed with different food, each 6 hour during 48 hours, and the other was left without feeding. The foods supplied were nauplii of Artemia sp, wild zooplankton, contreted micro-pulverized of 48% of protein for fishes. After ended the tests, it was found that the larvaes started external feeding (This is that the larvaes are born with some food for three days, after that, they got to start feeding from outside) at 72 hpe without watching cannibal behaviour. The best result for surviving,weight and size was when the larvaes were fed with the nauplii of Artemia sp. Two elements to highlight in the survey were; first that the larvaes accepted as first feeding a concentred commonly and second that they have actually grown up and survived as they did comparing with t, Uno de los grandes problemas que enfrenta la piscicultura moderna se encuentra en la etapa de larvicultura, ya que la gran población de larvas eclosionadas generalmente muere en el momento de iniciar su primera alimentación; los estudios realizados sobre éste aspecto en bagres nativos es escaso y especialmente para Rhamdia sebae. En la Unidad de Larvicultura del Instituto de Acuicultura de los Llanos (IALL), de la Universidad de los Llanos (Villavicencio), fueron realizados cuatro ensayos entre abril y mayo de 2004 para evaluar la influencia de la primera alimentación en el crecimiento y sobrevivencia de larvas de barbilla Rhamdia sebae. Las larvas se obtuvieron a partir de individuos silvestres mediante reproducción inducida con extracto de hipófisis de carpa (EHC). En cada uno de los cuatro ensayos, se experimentaron tres tipos de alimento frente a un testigo en ayuno, cada tratamiento se replicó tres veces. Para cada ensayo, se desarrollo el siguiente protocolo: a las 68 horas pos eclosión (hpe), las larvas fueron confinadas en recipientes de vidrio de 5 l, a densidad de 50 larvas /l (3 l útiles), con aireación permanente. A las 72 hpe las larvas se distribuyeron en cuatro grupos; tres de ellos se proveyeron con diferentes alimentos, cada seis horas durante 48 horas, y el otro se mantuvo en ayuno. Los alimentos ofrecidos fueron: naúplios de Artemia sp., zooplancton silvestre, concentrado micropulverizado para peces del 48% de proteína bruta. Finalizados los ensayos, se encontró que las larvas iniciaron alimentación exógena a las 72 ± 2 hpe sin observarse comportamiento caníbal. El mejor resultado de sobrevivencia, peso, y talla se obtuvo cuando las larvas fueron alimentadas con naúplios de Artemia sp. Dos elementos a resaltar en el presente trabajo son: primero que las larvas hayan aceptado como primer alimento un concentrado comercial y segundo que hayan crecido y sobrevivido de la manera que lo hicieron comparativamente con las larvas alimentadas con naúpliosde

The cannibal behavior is common in the fish and it is considered one of the main causes of mortality in the larviculture. Cannibalism is defined as special predation that kill a co-specific for consuming wholy or partially. Cannibalism has been classified into seven types, depending on life-history, age difference between cannibal and prey, and whether or not they are related. Cannibalism in the larviculture relates principally to intra and intercohorte sibling cannibalism. Also, we discuss the main endogenous and exogenous causes that stimulate the occurrence of the cannibalism in the nature. Among the endogenous causes they are piscivory, care parental and the size differences. Among the exogenous causes they are food availability and the populational density. This review shows a list of 55 important and potential cultured fish species displaying cannibalism. As the cannibalism it is a behavior adaptative under conditions of food shortage, in the larvicultura their main cause is associated to food availability. At the end of rewie there are recommendations for control of cannibalism under larviculture conditions., La conducta caníbal es común en los peces y se le considera una de las principales causas de mortalidad en la larvicultura. Esta conducta se define como un tipo especial de predación que consiste en matar a un coespecífico para consumirlo parcial o totalmente. El canibalismo ha sido clasificado en siete tipos dependiendo del estado de desarrollo de la presa, parentesco caníbal-presa y la relación de edad entre caníbal y presa. En la larvicultura el tipo de canibalismo es intracohorte o intercohorte. Además, se discuten las principales causas endógenas y exógenas que estimulan la ocurrencia del canibalismo en la naturaleza. Entre las causas endógenas se resalta la piscivoría, el cuidado parental y las diferencias de tamaño. Entre las causas exógenas se resalta la disponilidad de alimento y la densidad poblacional. Esta revisión presenta un listado de 55 especies de peces con potencialidad e importancia en la piscicultura que registran canibalismo durante la larvicultura. Como el canibalismo es una conducta adaptativa en condiciones de escasez de alimento, en la larvicultura su principal causa está asociada a la disponibilidad del alimento. Al final de la revisión se ofrecen recomendaciones para su control en la larvicultura.

In the Centro de Investigacion Piscicola de la Universidad de Cordoba were two experiments. In the first experiment was conducted to investigate the effects of different preys to first feeding on bocachico (Prochilodus magdalenae) larviculture. The onset feeding bocachico post-larvae stocked into aquarium at density 50/L, were fed at 5 Prey/mL during five days: Artemia nauplii (NA), descapsulated Artemia cysts (CA), wild zooplankton of 125 to 160 mm (Z125-160) and zooplankton of 250 to 400 mm (Z250-400). In addition, a group post-larvae was subjected to starvation. Bocachico post-larvae fed NA (2.0} 1.8 mg, 1.8} 0.9 mm) and Z250-400 (2.0} 1.1 mg, 1.6} 0.5 mm) were that offered better results for weight and total length gain (p<0.05). Item prey NA (73.2} 10.7%) was that offered better result survival rate (P<0.05). The low survival rate of post-larvae bocachico fed Z250-400 (49. 9} 23. 8%) can be explained to the mortality caused to presence of predator copepods (Termocyclops decipiens and Mesoscyclops aspericornis) in the offered wild zooplankton. The low growth of bocachico post-larvae fed with Z125-160 (0. 8} 0. 4 mg, 1. 1} 0. 2 mm) and CA (0. 5} 0. 9 mg, 0. 7} 0. 5 mm) can be explained because item Z125-160 was small for the oral opening (671} 12. 8 mm) and therefore inefficient in the energy balance; while item CA behaved as an inert food that did not stimulate their consumption. In the second experiment was conducted to investigate the effects of different periods of first feeding on growth and survival of post-larval bocachico during different periods (1, 3, 5 and 7 days) of first feeding. No differences were noted in the survival among first feeding periods (P>0.05). The post-larvae fed during 7 days presented higher weight gain (5.3} 3.8 mg) and length gain (2.8} 1.6 mm) than other experimental groups (P<0.05). The weight gain did not differ among the post-larvae fed between 3 and 5 days (P>0.05). The specific growth rates were not significantly different be, En el Centro de Investigacion Piscicola de la Universidad de Cordoba se realizaron dos experimentos; en el primero, el objetivo fue evaluar el efecto de diferentes presas en el manejo de la primera alimentacion del bocachico Prochilodus magdalenae y en el segundo, con la mejor presa del ensayo anterior, determinar el tiempo minimo de manejo de la primera alimentacion. En ambos casos las post-larvas fueron sembradas a 50/ L en acuario de 5 L. En el primer experimento se evaluaron las siguientes presas: nauplios de Artemia (NA), cistos descapsulados de Artemia (CA), zooplancton silvestre tamizado entre 125-160 Êm (Z125-160) y zooplancton silvestre tamizado entre 250-400 Êm (Z250-400), ofrecidas durante cinco dias a razon de 5 Presa/mL. Ademas, un grupo de post-larvas fue sometida a ayuno. Las mayores ganancias de peso y longitud total la registraron las post-larvas alimentadas con NA (2.0}1.8 mg, 1.8}0.9 mm) y Z250-400 (2.0}1.1 mg, 1.6}0.5 mm). La sobrevivencia de las post-larvas alimentadas con NA (73.2}10.7%) fue mayor a las registradas en los demas tratamientos (P<0.05). La baja sobrevivencia de las post-larvas alimentadas con Z250-400 Êm (49.9}23.8%) se debio a la mortalidad ocasionada por la presencia de copepodos predadores en el zooplancton ofrecido (Mesocyclops sp, Thermocyclops decipiens ). El pobre crecimiento de las post-larvas alimentadas con Z125- 160 (0.8} 0.4 mg, 1.1}0.2 mm) y CA (0.5} 0.9 mg, 0.7} 0.5 mm) fue debido en el caso del zooplancton porque resulto pequeno para la abertura bucal del bocachico (671} 12.8 mm) y por tanto ineficiente en el balance energetico; mientras que en el caso de CA este se comporto como un alimento inerte que no estimulo su consumo. En el segundo ensayo se ofrecio NA durantes diferentes periodos: 1, 3, 5 y 7 dias, a razon de 5 presas/mL. No se observaron diferencias significativas en la sobrevivencia final entre los diferentes tratamientos; la cual oscilo entre 86.0} 9.8% (1 dia) y 91.1} 7,7% (3 dias). Las post-larvas alim