Silvie Dumas - Academia.edu (original) (raw)
Papers by Silvie Dumas
CICIMAR Oceánides, 2015
The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feedi... more The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feeding at day 3 after hatching at 26º C was studied. Ten larvae were directly observed during 5 min each before and after the addition of feed. Rotifers (Brachionus rotundiformis) and copepod nauplii (Euterpina acutifrons) were used as live feed at a density of 5 prey/ml. Larval behavior was described before and after prey addition. Also, the number of larvae that displayed an attack posture and the number of attacks per larvae during the observationperiod were recorded. Before prey addition, the larvae displayed three types of conduct: swimming, resting and fast impulse. This behavioral pattern changed with the presence of feed, regardless of prey type. The swimming conduct increased duration but changed to a short distance and frequent pauses. The resting conduct reduced itsduration and two new modal action patterns associated to feeding were present: “S” posture after prey detection and t...
Latin American Journal of Aquatic Research, 2021
The potential of Panagrolaimus sp. nematode as a live prey was assessed in longfin yellowtail Ser... more The potential of Panagrolaimus sp. nematode as a live prey was assessed in longfin yellowtail Seriola rivoliana larval rearing. Larvae were reared from 3-11 days post-hatching (dph) in a 2000 L tank and fed on copepods and rotifers. On 12 dph, larvae were transferred to eight 200 L tanks at a density of 12 larvae L -1 to start the feeding trial, consisting of two treatments ( Artemia or nematodes) using four replicates each. Rotifers were offered on 12 dph with a "co-feeding" from 14 to 16 dph (rotifer/enriched Artemia or rotifer/nematode). Only Artemia or nematodes were supplied from 17 to 19 dph. Feeding incidence was 80-90% on 14 dph, but more larvae were capturing rotifers than Artemia or nematodes. Artemia consumption increased more than nematodes at 19 dph, though it was not significantly different. Significantly lower enterocyte and villus heights in the posterior intestine were observed at 19 dph in larvae fed on nematodes but only in enterocyte height in the anter...
CICIMAR oceánides, Dec 31, 2015
RESUMEN. El comportamiento alimentario de larvas del huachinango del Pacífico fue estudiado bajo ... more RESUMEN. El comportamiento alimentario de larvas del huachinango del Pacífico fue estudiado bajo condiciones controladas, con énfasis especial durante el inicio de la alimentación exógena (al tercer día después de la eclosión). Durante un periodo de cinco minutos fueron observadas de manera individual diez larvas de L. peru, antes y después de ser alimentadas con rotíferos (Brachionus rotundiformis) y nauplios de copépodos (Euterpina acutifrons) en densidades de 5 presas/ml. Para describir parte del comportamiento relacionado con el evento de alimentación se registró el número de veces que las larvas adoptaron una "postura" de ataque, así como el número de ataques por larva a los diferentes tipos presa. Se observó que previo al suministro de alimento, las larvas despliegan tres tipos de conducta: nado, reposo, e impulso rápido. Una vez que fue suministrado el alimento, el patrón de conducta de las larvas cambió, independientemente del tipo de presa. La frecuencia de nado incrementó pero los desplazamientos fueron más cortos y pausas más frecuentes. El periodo de reposo de las larvas disminuyó significativamente y se observaron dos patrones de acción modal asociados directamente al proceso de alimentación: 1) postura sigmoide ("S"), adoptada posterior a la detección de una presa, 2) ataque, evento durante el cual la larva se impulsa espontáneamente en dirección de la presa, independientemente de si se logra o no la captura del alimento. Menos del 50 % de las larvas observadas desplegaron una postura de ataque y el número promedio de ataques por larva durante el tiempo de observación fue menor a 1.5, independientemente del tipo de presa. Los resultados son similares a los reportados para otras larvas de peces durante el inicio de la alimentación exógena y sugieren que los nauplios de copépodos son una presa adecuada durante la primera alimentación de las larvas de L. peru. Palabras clave: Huachinango del Pacífico, Lutjanus peru, primera alimentación, comportamiento alimentario. Feeding behaviour of the Pacific red snapper Lutjanus peru (Nichols & Murphy, 1922) (Percoidei: Lutjanidae) larvae at the onset of exogenous feeding ABSTRACT. The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feeding at day 3 after hatching at 26º C was studied. Ten larvae were directly observed during 5 min each before and after the addition of feed. Rotifers (Brachionus rotundiformis) and copepod nauplii (Euterpina acutifrons) were used as live feed at a density of 5 prey/ml. Larval behavior was described before and after prey addition. Also, the number of larvae that displayed an attack posture and the number of attacks per larvae during the observation period were recorded. Before prey addition, the larvae displayed three types of conduct: swimming, resting and fast impulse. This behavioral pattern changed with the presence of feed, regardless of prey type. The swimming conduct increased duration but changed to a short distance and frequent pauses. The resting conduct reduced its duration and two new modal action patterns associated to feeding were present: "S" posture after prey detection and the attack which consisted in a direct larval strike towards the prey and may include prey capture. Less than 50% of the observed larvae displayed the attack posture and the mean number of attacks per larvae was less than 1.5 during the observation period regardless of prey type. Results are similar to the reported for other species during the onset of exogenous feeding and suggest that copepod nauplii may be a more suitable prey during first feeding of L. peru.
Aquaculture, 2021
Abstract The Pacific red snapper (Lutjanus peru) is very popular fishery that reaches high prices... more Abstract The Pacific red snapper (Lutjanus peru) is very popular fishery that reaches high prices in the market that is distributed in tropical and subtropical climates. Most studies in fatty acid requirements for larval production are done in temperate species; in general, warm-water fish are given the same levels of DHA and EPA than cold-water fish, which increases considerably the costs of production, without apparent benefit. We analyzed spawns during lecithotrophic development, with emphasis on fatty acids, of L. peru. Three origins were compared, Wild spawns, used as the standard of better-quality larvae, Laboratory and Pond, each with some differences in the inductions of maturation and broodstock diet: Lab and Pond broodstock were fed sardines and squids and DHA-rich oil capsules were added once a week. A total of 87 spawns were sampled throughout three years of sampling. Egg and oil globule diameters before fertilization, in 1-h embryo (E) and before hatching (LE); larval total length and oil globule diameter at hatching (LH), and after 24 (L24h) and 48 h (L48h) were measured. Hatching and survival percentages were measured in triplicate for each spawn. Hatching were significantly higher from Pond spawns (75.7%) compared to Wild (60.8%). Survival at L48 hours was not significantly different among origins. Wild spawns had significantly more carbohydrates, but less phospholipids during development, compared to Lab and Pond spawns. ARA, EPA and DHA concentrations decreased in total lipids and triglycerides, but in Lab spawns they were accumulated in phospholipids. There was a more variable fatty acid composition in Pond spawns compared to Lab spawns, a result of more diversified diet in ponds. Viable eggs had two-fold higher proportion of ARA compared to non-viable eggs. A principal factor analysis revealed three positive associations between 1) female weight, egg oil globule diameter, and EPA:ARA in egg PL; 2) hatching, LH length, and DHA:ARA in egg PL; 3) L48h survival, TG and PL content in eggs. According to our results, subtropical L. peru needs less DHA and more ARA and monounsaturated fatty acids in their diet, compared to temperate marine fish.
Hormonal induction was investigated in order to induce and synchronize the spawning of spotted sa... more Hormonal induction was investigated in order to induce and synchronize the spawning of spotted sand bass ( Paralabrax maculatofasciatus ). We conducted three experiments with wild fish captured in the Gulf of California: 1) Spawning induction with LHRHa, 2) LHRHa effects on motility and sperm cell density (both experiments using LHRHa concentrations of 25, 50, 100 µg kg -1 and saline solution), 3) Induction and incubation of spawns obtained with LHRHa, using concentrations of 12. 5, 25, 50 µg kg -1 and saline solution. In experiment 1, a higher spawning ratio was observed in the conce ntration of 25 µg kg -1 ; however, no significant differences were observed in the proportion of floating (viable) eggs. In experiment 2, significant differences ( P P µg kg -1 showing the higher densities. In experiment 3, significant differences ( P µg kg -1 , respectively. Survival at hatching and proportion of live yolk-sac larvae were significantly higher ( P µg kg -1 . In this work, LHRHa was e f...
Ciencias Marinas, 2016
Three experiments assessed the effects of cold-shock induced triploidy on (1) the incidence of ab... more Three experiments assessed the effects of cold-shock induced triploidy on (1) the incidence of abnormal cell cleavage during embryogenesis, (2) hatching success and the proportion of live yolk-sac larvae in normally cleaved versus abnormally cleaved embryos, and (3) survival of triploid larvae of spotted sand bass (Paralabrax maculatofasciatus). All spawns were obtained by hormonal induction (LHRHa). Triploidy was induced by cold shock shortly after fertilization. In experiment 1, the percentage of abnormal cell cleavage was significantly higher (P < 0.05) in the cold-shocked group than in the control group, while the hatching rate and the proportion of live yolk-sac larvae were significantly lower (P < 0.05). In experiment 2, when normally and abnormally cleaved embryos from the control and cold-shocked groups were incubated separately, normal cleaved embryos in the cold-shocked group showed a significantly higher hatching rate and proportion of live yolk-sac larvae than abno...
Fish Physiology and Biochemistry, 2008
Fish & Shellfish Immunology, 2005
Genes encoding two major outer membrane proteins (OMPs) of the bacterial pathogen Aeromonas veron... more Genes encoding two major outer membrane proteins (OMPs) of the bacterial pathogen Aeromonas veronii, Omp38 and Omp48, were used to construct DNA vaccines. The protective effect of such vaccines against motile aeromonad septicaemia was evaluated in spotted sand bass (Paralabrax maculatofasciatus), an endemic species of the Mexican Northwest Pacific coast and a potential resource for the aquaculture industry. Weak protein expression, as determined by immunoblotting, was observed after transfection of eukaryotic cells with the DNA vaccines. Fish immunized with a single intramuscular injection of 20 Palabras clave: Spotted sand bass, Paralabrax maculatofasciatus, Genetic immunization, Immune response, Outer membrane proteins, Bacterial antigens, Aeromonas spp, Fish immunology Para obtener copia del documento contacta con el autor (sdumas@ipn.mx) o con el personal de la biblioteca
Aquaculture Research, 1996
Survival of hybrids (FA. AF) between brook charr. Saiveiinus fontinaiis (Mitchill), (FF) and Arct... more Survival of hybrids (FA. AF) between brook charr. Saiveiinus fontinaiis (Mitchill), (FF) and Arctic charr, Saiveiinus aipinus L.. (AA) were compared at three fish farms. Survival of hybrids and Arctic charr was impaired in warm water. In cold water, brook charr and hybrids showed similar survival percentages until the spawning period. Each spawning period was followed by an increase of mortality, but to a much higher degree in brook charr. Growth was studied in the best (cold water) fish farm. During the first 2 years of rearing, brook charr had the highest relative weight. The weight of the two hybrids approached that of brook charr in the third year because of the drastic decrease of growth rate in brook charr after the spawning period. No differences between genotypes of either females or males could be detected in the eviscerated weights, the dressing percentages, or the gonadosomatic indexes. The two hybrids matured sexually, but their sperm quality w^s inferior to that of the pure species. Crosses between the 4-year-old breeders from the Fl population (FF, FA, AF and AA) were achieved. Survival from the eyed stage to 6 weeks post-hatching was significantly lower in F2 progeny than in backcrosses or pure species crosses. Even though the stirvival following spawning periods and the total biomass produced were better in hybrids than in brook charr raised in cold water, we believe the farming of this hybrid should not be carried out. The full development of sexually mature hybrids does not resolve problems linked with precocious sexual maturation in brook charr fanning carried out in eastern Canada.
Aquaculture, 1992
The early development ofhybrids between brook chat'r (S. /ontin&) and Arc:ic charr (S. alpmus). A... more The early development ofhybrids between brook chat'r (S. /ontin&) and Arc:ic charr (S. alpmus). Aqwcfdfwe, 108: 21-28. Reciprocal hybrids between brmk chart and Arctic than were compared to parental species from fertilization to 10 weeks after the beginning offceding. At the end of the experiment, higher survival rates (58.6% f 1.5) were observed for brook charr (FF) than for Arctic charr (AA: 48.1% f2.2). whileboth hybridswcrcintermediate (Arcticcharrdam x braokcharrrire (AF): 57.5% 20.9: brook charr dam x Arctic charr sire (FA): 53.8% & 1.4). Al: during the studied period, survival rates of hybrids were intermediate to parental species. Effects of parental species on the length ofthe incubation period (LIP) were signiticant but difl?red according to dam and sire species. LIP was 43 I.6 HI.9 degree-days for AF, 454.4t2.2 for ,&A. 503.420.9 for FF, and 518.6+ I.6 for FA. Individual sire effects on early survival and on the length of incubation period showed significant sire cf&cts only on the length of the incubation period and only amor. bmok trout sires in pure species,
Aquaculture, 2001
A preliminary feeding trial was made to determine the effect of dietary protein level on growth Ž... more A preliminary feeding trial was made to determine the effect of dietary protein level on growth Ž. and body composition of juvenile spotted sand bass Paralabrax maculatofasciatus 9.5 g. Fish Ž. were randomly distributed in nine 600-l circular tanks 42 fishrtank , which were connected to a closed water recirculating system. Fish were fed practical diets for 93 days containing increasing Ž. Ž. protein levels 40%, 45%, and 50%. Significant lower weight P-0.05 was observed in fish fed Ž. the 40% protein diet 43.1 g compared to fish fed higher proteins diets. Growth rates, evaluated b X Ž. by an exponential model Y s ae , and gross energy retention GER were significantly higher in Ž. fish fed the 45% and 50% protein diets than the fish fed the 40% diet P-0.05. No significant difference among dietary protein levels was detected for the other growth variables measured, nor for the proximate composition of the whole fish, liver, or muscle. The use of a practical diet containing at least 45% protein is appropriate for growth of spotted sand bass juveniles.
Indian journal of science and technology, 2011
Aquaculture Research, 2007
Latin American Journal of Aquatic Research
The spotted rose snapper Lutjanus guttatus is a fishery relevant species from the eastern Pacific... more The spotted rose snapper Lutjanus guttatus is a fishery relevant species from the eastern Pacific Ocean, with aquaculture potential. Species-specific genetic markers are needed for the genetic characterization of wild and cultivated populations to help management strategies. Eighteen hypervariable microsatellites were developed by Next Generation Sequencing and characterized in a wild population sample. Genetic diversity was high (observed heterozygosity = 0.88 ± 0.050; the number of alleles per locus = 13.4 ± 1.3) and few loci departed from the Hardy-Weinberg Equilibrium, leaving 14 loci potentially suitable for population genetic studies. A reduced panel of five loci was tested in a cultivated stock to determine the parentage of progeny (embryonated eggs; n = 413), to estimate the temporal contribution of each parental broodstock. The above resulted in the successful assignment of 95.6% of the progeny to its parental couple, representing 17 out of the 24 possible families. Two of ...
Homeopathy
Background Homeopathy has been widely applied in freshwater species but rarely in marine fish. Fa... more Background Homeopathy has been widely applied in freshwater species but rarely in marine fish. Farm stress destabilises host–pathogen equilibrium, favouring parasites and disease. Coccidian endoparasites cause intestinal infections and cell degeneration. Materials and Methods Naturally parasite-infested juvenile snapper Lutjanus guttatus (n = 430; weight 1.9 ± 0.01 g; length 4.9 ± 0.03 cm) specimens were distributed in group sizes of 43, in 10 fiberglass tanks (100 L) with aeration and continuous water change. Five groups in duplicate were assessed: Passival (PaV); Passival and Phosphoricum acid Similia (PaV–PhA); Passival and Silicea terra Similia (PaV–SiT); Endecto and Infecçoes (End–Inf) and a control (Ethanol) for 45 days. Feed was sprinkled with treatment (5% v/w) and dried to avoid ethanol side-effects. Statistical results were expressed as mean ± standard error of the mean. Results Intestinal coccidia were recorded histopathologically, with the least incidence attained at T45...
CICIMAR Oceánides, 2015
The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feedi... more The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feeding at day 3 after hatching at 26º C was studied. Ten larvae were directly observed during 5 min each before and after the addition of feed. Rotifers (Brachionus rotundiformis) and copepod nauplii (Euterpina acutifrons) were used as live feed at a density of 5 prey/ml. Larval behavior was described before and after prey addition. Also, the number of larvae that displayed an attack posture and the number of attacks per larvae during the observationperiod were recorded. Before prey addition, the larvae displayed three types of conduct: swimming, resting and fast impulse. This behavioral pattern changed with the presence of feed, regardless of prey type. The swimming conduct increased duration but changed to a short distance and frequent pauses. The resting conduct reduced itsduration and two new modal action patterns associated to feeding were present: “S” posture after prey detection and t...
Latin American Journal of Aquatic Research, 2021
The potential of Panagrolaimus sp. nematode as a live prey was assessed in longfin yellowtail Ser... more The potential of Panagrolaimus sp. nematode as a live prey was assessed in longfin yellowtail Seriola rivoliana larval rearing. Larvae were reared from 3-11 days post-hatching (dph) in a 2000 L tank and fed on copepods and rotifers. On 12 dph, larvae were transferred to eight 200 L tanks at a density of 12 larvae L -1 to start the feeding trial, consisting of two treatments ( Artemia or nematodes) using four replicates each. Rotifers were offered on 12 dph with a "co-feeding" from 14 to 16 dph (rotifer/enriched Artemia or rotifer/nematode). Only Artemia or nematodes were supplied from 17 to 19 dph. Feeding incidence was 80-90% on 14 dph, but more larvae were capturing rotifers than Artemia or nematodes. Artemia consumption increased more than nematodes at 19 dph, though it was not significantly different. Significantly lower enterocyte and villus heights in the posterior intestine were observed at 19 dph in larvae fed on nematodes but only in enterocyte height in the anter...
CICIMAR oceánides, Dec 31, 2015
RESUMEN. El comportamiento alimentario de larvas del huachinango del Pacífico fue estudiado bajo ... more RESUMEN. El comportamiento alimentario de larvas del huachinango del Pacífico fue estudiado bajo condiciones controladas, con énfasis especial durante el inicio de la alimentación exógena (al tercer día después de la eclosión). Durante un periodo de cinco minutos fueron observadas de manera individual diez larvas de L. peru, antes y después de ser alimentadas con rotíferos (Brachionus rotundiformis) y nauplios de copépodos (Euterpina acutifrons) en densidades de 5 presas/ml. Para describir parte del comportamiento relacionado con el evento de alimentación se registró el número de veces que las larvas adoptaron una "postura" de ataque, así como el número de ataques por larva a los diferentes tipos presa. Se observó que previo al suministro de alimento, las larvas despliegan tres tipos de conducta: nado, reposo, e impulso rápido. Una vez que fue suministrado el alimento, el patrón de conducta de las larvas cambió, independientemente del tipo de presa. La frecuencia de nado incrementó pero los desplazamientos fueron más cortos y pausas más frecuentes. El periodo de reposo de las larvas disminuyó significativamente y se observaron dos patrones de acción modal asociados directamente al proceso de alimentación: 1) postura sigmoide ("S"), adoptada posterior a la detección de una presa, 2) ataque, evento durante el cual la larva se impulsa espontáneamente en dirección de la presa, independientemente de si se logra o no la captura del alimento. Menos del 50 % de las larvas observadas desplegaron una postura de ataque y el número promedio de ataques por larva durante el tiempo de observación fue menor a 1.5, independientemente del tipo de presa. Los resultados son similares a los reportados para otras larvas de peces durante el inicio de la alimentación exógena y sugieren que los nauplios de copépodos son una presa adecuada durante la primera alimentación de las larvas de L. peru. Palabras clave: Huachinango del Pacífico, Lutjanus peru, primera alimentación, comportamiento alimentario. Feeding behaviour of the Pacific red snapper Lutjanus peru (Nichols & Murphy, 1922) (Percoidei: Lutjanidae) larvae at the onset of exogenous feeding ABSTRACT. The behaviour of the Pacific red snapper Lutjanus peru larvae during the onset of exogenous feeding at day 3 after hatching at 26º C was studied. Ten larvae were directly observed during 5 min each before and after the addition of feed. Rotifers (Brachionus rotundiformis) and copepod nauplii (Euterpina acutifrons) were used as live feed at a density of 5 prey/ml. Larval behavior was described before and after prey addition. Also, the number of larvae that displayed an attack posture and the number of attacks per larvae during the observation period were recorded. Before prey addition, the larvae displayed three types of conduct: swimming, resting and fast impulse. This behavioral pattern changed with the presence of feed, regardless of prey type. The swimming conduct increased duration but changed to a short distance and frequent pauses. The resting conduct reduced its duration and two new modal action patterns associated to feeding were present: "S" posture after prey detection and the attack which consisted in a direct larval strike towards the prey and may include prey capture. Less than 50% of the observed larvae displayed the attack posture and the mean number of attacks per larvae was less than 1.5 during the observation period regardless of prey type. Results are similar to the reported for other species during the onset of exogenous feeding and suggest that copepod nauplii may be a more suitable prey during first feeding of L. peru.
Aquaculture, 2021
Abstract The Pacific red snapper (Lutjanus peru) is very popular fishery that reaches high prices... more Abstract The Pacific red snapper (Lutjanus peru) is very popular fishery that reaches high prices in the market that is distributed in tropical and subtropical climates. Most studies in fatty acid requirements for larval production are done in temperate species; in general, warm-water fish are given the same levels of DHA and EPA than cold-water fish, which increases considerably the costs of production, without apparent benefit. We analyzed spawns during lecithotrophic development, with emphasis on fatty acids, of L. peru. Three origins were compared, Wild spawns, used as the standard of better-quality larvae, Laboratory and Pond, each with some differences in the inductions of maturation and broodstock diet: Lab and Pond broodstock were fed sardines and squids and DHA-rich oil capsules were added once a week. A total of 87 spawns were sampled throughout three years of sampling. Egg and oil globule diameters before fertilization, in 1-h embryo (E) and before hatching (LE); larval total length and oil globule diameter at hatching (LH), and after 24 (L24h) and 48 h (L48h) were measured. Hatching and survival percentages were measured in triplicate for each spawn. Hatching were significantly higher from Pond spawns (75.7%) compared to Wild (60.8%). Survival at L48 hours was not significantly different among origins. Wild spawns had significantly more carbohydrates, but less phospholipids during development, compared to Lab and Pond spawns. ARA, EPA and DHA concentrations decreased in total lipids and triglycerides, but in Lab spawns they were accumulated in phospholipids. There was a more variable fatty acid composition in Pond spawns compared to Lab spawns, a result of more diversified diet in ponds. Viable eggs had two-fold higher proportion of ARA compared to non-viable eggs. A principal factor analysis revealed three positive associations between 1) female weight, egg oil globule diameter, and EPA:ARA in egg PL; 2) hatching, LH length, and DHA:ARA in egg PL; 3) L48h survival, TG and PL content in eggs. According to our results, subtropical L. peru needs less DHA and more ARA and monounsaturated fatty acids in their diet, compared to temperate marine fish.
Hormonal induction was investigated in order to induce and synchronize the spawning of spotted sa... more Hormonal induction was investigated in order to induce and synchronize the spawning of spotted sand bass ( Paralabrax maculatofasciatus ). We conducted three experiments with wild fish captured in the Gulf of California: 1) Spawning induction with LHRHa, 2) LHRHa effects on motility and sperm cell density (both experiments using LHRHa concentrations of 25, 50, 100 µg kg -1 and saline solution), 3) Induction and incubation of spawns obtained with LHRHa, using concentrations of 12. 5, 25, 50 µg kg -1 and saline solution. In experiment 1, a higher spawning ratio was observed in the conce ntration of 25 µg kg -1 ; however, no significant differences were observed in the proportion of floating (viable) eggs. In experiment 2, significant differences ( P P µg kg -1 showing the higher densities. In experiment 3, significant differences ( P µg kg -1 , respectively. Survival at hatching and proportion of live yolk-sac larvae were significantly higher ( P µg kg -1 . In this work, LHRHa was e f...
Ciencias Marinas, 2016
Three experiments assessed the effects of cold-shock induced triploidy on (1) the incidence of ab... more Three experiments assessed the effects of cold-shock induced triploidy on (1) the incidence of abnormal cell cleavage during embryogenesis, (2) hatching success and the proportion of live yolk-sac larvae in normally cleaved versus abnormally cleaved embryos, and (3) survival of triploid larvae of spotted sand bass (Paralabrax maculatofasciatus). All spawns were obtained by hormonal induction (LHRHa). Triploidy was induced by cold shock shortly after fertilization. In experiment 1, the percentage of abnormal cell cleavage was significantly higher (P < 0.05) in the cold-shocked group than in the control group, while the hatching rate and the proportion of live yolk-sac larvae were significantly lower (P < 0.05). In experiment 2, when normally and abnormally cleaved embryos from the control and cold-shocked groups were incubated separately, normal cleaved embryos in the cold-shocked group showed a significantly higher hatching rate and proportion of live yolk-sac larvae than abno...
Fish Physiology and Biochemistry, 2008
Fish & Shellfish Immunology, 2005
Genes encoding two major outer membrane proteins (OMPs) of the bacterial pathogen Aeromonas veron... more Genes encoding two major outer membrane proteins (OMPs) of the bacterial pathogen Aeromonas veronii, Omp38 and Omp48, were used to construct DNA vaccines. The protective effect of such vaccines against motile aeromonad septicaemia was evaluated in spotted sand bass (Paralabrax maculatofasciatus), an endemic species of the Mexican Northwest Pacific coast and a potential resource for the aquaculture industry. Weak protein expression, as determined by immunoblotting, was observed after transfection of eukaryotic cells with the DNA vaccines. Fish immunized with a single intramuscular injection of 20 Palabras clave: Spotted sand bass, Paralabrax maculatofasciatus, Genetic immunization, Immune response, Outer membrane proteins, Bacterial antigens, Aeromonas spp, Fish immunology Para obtener copia del documento contacta con el autor (sdumas@ipn.mx) o con el personal de la biblioteca
Aquaculture Research, 1996
Survival of hybrids (FA. AF) between brook charr. Saiveiinus fontinaiis (Mitchill), (FF) and Arct... more Survival of hybrids (FA. AF) between brook charr. Saiveiinus fontinaiis (Mitchill), (FF) and Arctic charr, Saiveiinus aipinus L.. (AA) were compared at three fish farms. Survival of hybrids and Arctic charr was impaired in warm water. In cold water, brook charr and hybrids showed similar survival percentages until the spawning period. Each spawning period was followed by an increase of mortality, but to a much higher degree in brook charr. Growth was studied in the best (cold water) fish farm. During the first 2 years of rearing, brook charr had the highest relative weight. The weight of the two hybrids approached that of brook charr in the third year because of the drastic decrease of growth rate in brook charr after the spawning period. No differences between genotypes of either females or males could be detected in the eviscerated weights, the dressing percentages, or the gonadosomatic indexes. The two hybrids matured sexually, but their sperm quality w^s inferior to that of the pure species. Crosses between the 4-year-old breeders from the Fl population (FF, FA, AF and AA) were achieved. Survival from the eyed stage to 6 weeks post-hatching was significantly lower in F2 progeny than in backcrosses or pure species crosses. Even though the stirvival following spawning periods and the total biomass produced were better in hybrids than in brook charr raised in cold water, we believe the farming of this hybrid should not be carried out. The full development of sexually mature hybrids does not resolve problems linked with precocious sexual maturation in brook charr fanning carried out in eastern Canada.
Aquaculture, 1992
The early development ofhybrids between brook chat'r (S. /ontin&) and Arc:ic charr (S. alpmus). A... more The early development ofhybrids between brook chat'r (S. /ontin&) and Arc:ic charr (S. alpmus). Aqwcfdfwe, 108: 21-28. Reciprocal hybrids between brmk chart and Arctic than were compared to parental species from fertilization to 10 weeks after the beginning offceding. At the end of the experiment, higher survival rates (58.6% f 1.5) were observed for brook charr (FF) than for Arctic charr (AA: 48.1% f2.2). whileboth hybridswcrcintermediate (Arcticcharrdam x braokcharrrire (AF): 57.5% 20.9: brook charr dam x Arctic charr sire (FA): 53.8% & 1.4). Al: during the studied period, survival rates of hybrids were intermediate to parental species. Effects of parental species on the length ofthe incubation period (LIP) were signiticant but difl?red according to dam and sire species. LIP was 43 I.6 HI.9 degree-days for AF, 454.4t2.2 for ,&A. 503.420.9 for FF, and 518.6+ I.6 for FA. Individual sire effects on early survival and on the length of incubation period showed significant sire cf&cts only on the length of the incubation period and only amor. bmok trout sires in pure species,
Aquaculture, 2001
A preliminary feeding trial was made to determine the effect of dietary protein level on growth Ž... more A preliminary feeding trial was made to determine the effect of dietary protein level on growth Ž. and body composition of juvenile spotted sand bass Paralabrax maculatofasciatus 9.5 g. Fish Ž. were randomly distributed in nine 600-l circular tanks 42 fishrtank , which were connected to a closed water recirculating system. Fish were fed practical diets for 93 days containing increasing Ž. Ž. protein levels 40%, 45%, and 50%. Significant lower weight P-0.05 was observed in fish fed Ž. the 40% protein diet 43.1 g compared to fish fed higher proteins diets. Growth rates, evaluated b X Ž. by an exponential model Y s ae , and gross energy retention GER were significantly higher in Ž. fish fed the 45% and 50% protein diets than the fish fed the 40% diet P-0.05. No significant difference among dietary protein levels was detected for the other growth variables measured, nor for the proximate composition of the whole fish, liver, or muscle. The use of a practical diet containing at least 45% protein is appropriate for growth of spotted sand bass juveniles.
Indian journal of science and technology, 2011
Aquaculture Research, 2007
Latin American Journal of Aquatic Research
The spotted rose snapper Lutjanus guttatus is a fishery relevant species from the eastern Pacific... more The spotted rose snapper Lutjanus guttatus is a fishery relevant species from the eastern Pacific Ocean, with aquaculture potential. Species-specific genetic markers are needed for the genetic characterization of wild and cultivated populations to help management strategies. Eighteen hypervariable microsatellites were developed by Next Generation Sequencing and characterized in a wild population sample. Genetic diversity was high (observed heterozygosity = 0.88 ± 0.050; the number of alleles per locus = 13.4 ± 1.3) and few loci departed from the Hardy-Weinberg Equilibrium, leaving 14 loci potentially suitable for population genetic studies. A reduced panel of five loci was tested in a cultivated stock to determine the parentage of progeny (embryonated eggs; n = 413), to estimate the temporal contribution of each parental broodstock. The above resulted in the successful assignment of 95.6% of the progeny to its parental couple, representing 17 out of the 24 possible families. Two of ...
Homeopathy
Background Homeopathy has been widely applied in freshwater species but rarely in marine fish. Fa... more Background Homeopathy has been widely applied in freshwater species but rarely in marine fish. Farm stress destabilises host–pathogen equilibrium, favouring parasites and disease. Coccidian endoparasites cause intestinal infections and cell degeneration. Materials and Methods Naturally parasite-infested juvenile snapper Lutjanus guttatus (n = 430; weight 1.9 ± 0.01 g; length 4.9 ± 0.03 cm) specimens were distributed in group sizes of 43, in 10 fiberglass tanks (100 L) with aeration and continuous water change. Five groups in duplicate were assessed: Passival (PaV); Passival and Phosphoricum acid Similia (PaV–PhA); Passival and Silicea terra Similia (PaV–SiT); Endecto and Infecçoes (End–Inf) and a control (Ethanol) for 45 days. Feed was sprinkled with treatment (5% v/w) and dried to avoid ethanol side-effects. Statistical results were expressed as mean ± standard error of the mean. Results Intestinal coccidia were recorded histopathologically, with the least incidence attained at T45...