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Age and growth of the king mackerel (Scomberomorus Cavalla) off the northeastern coast of Brazil
Nóbrega, Marcelo Francisco de;Lessa, Rosangela Paula;
Brazilian Journal of Oceanography , 2009, DOI: 10.1590/S1679-87592009000400003
Abstract: age and growth of the king mackerel (scomberomorus cavalla) were estimated for northeastern brazil. a total of 405 sagittal otoliths from 140 males (24.4-112 cm), 73 females (28-114.8 cm) and 193 specimens of unknown sex (11.5-121 cm) were examined. marginal increment analysis indicated an annual pattern for growth band deposition. the age classes ranged from 1 to 15 years. length ranged from 11.5 to 121 cm. the schnute model indicated that the von bertalanffy growth model demonstrated the best adjustment, with p=1/b, and was therefore used for estimating growth. back-calculated curves had smaller variances, giving the following estimated growth parameters for males: l∞= 116.8 cm, k = 0.190, t0 = 0.377; and females: l∞= 132.7 cm, k = 0.159 and t0 = 0.387. in order to compare the curves for males and females, the overlapping of 95% confidence intervals was performed for the parameters generated from the von bertalanffy non-linear least square method. specimens between 3 and 8 years of age represented 82.2% (n=5,783) of the catch composition, characterizing the species as a catchable stock in the region.
Age and growth of Spanish mackerel (Scomberomorus brasiliensis) off the northeastern coast of Brazil
Nóbrega, Marcelo Francisco de;Lessa, Rosangela Paula;
Neotropical Ichthyology , 2009, DOI: 10.1590/S1679-62252009000400016
Abstract: age and growth of the spanish mackerel (scomberomorus brasiliensis) caught off northeastern brazil were determined. a total of 831 otoliths were examined - 296 from males (12 - 75 cm fl), 212 from females (11.5 - 72 cm fl) and 323 from specimens of undetermined sex (12.4 - 75 cm fl). there was a high percentage of juveniles in the catches, resulting mainly from the use of gillnets. marginal increment analysis of the otoliths indicated that the shortest distances from the last ring to the edge occurred from november to may, laying down just one ring annually. one to eight rings were found, with specimen lengths ranging from 11.5 to 75.8 cm. the schunute model was used to determine what model was best fit the data, demonstrating that the specialized von bertalanffy growth equation is the most appropriate. curves were established for males (l∞ = 79.52 cm, k = 0.189, t0 = -0.384 year) and females (l∞ = 109.18 cm, k = 0.114, t0 = -0.414 year), which resulted in distinct growth patterns between sexes. based on the parameters estimated for the sexes separately, males have an approximate longevity of 15.5 years, whereas female longevity is 25.9 years. specimens between 2 and 6 years of age represented 86% (n = 5,290) of the catch composition, characterizing the species as a catchable stock in the region. the present study updates essential information for assessing the stock of this important resource, for which the last growth studies in the region were carried out approximately thirty years ago.
Tandemly repeated sequence in 5’end of mtDNA control region of Japanese Spanish mackerel Scomberomorus niphonius
BN Shui, ZQ Han, TX Gao, ZQ Miao
African Journal of Biotechnology , 2008,
Abstract: Extensive length variability was observed in 5’ end sequence of the mitochondrial DNA control region of the Japanese Spanish mackerel (Scomberomorus niphonius). This length variability was due to the presence of varying numbers of a 56-bp tandemly repeated sequence and a 46-bp insertion/deletion (indel). The structure and organization of this segment is similar to that of other teleost fish and vertebrates. However, extensive variation in the copy number of tandem repeats (0–5 copies) and the presence of a relatively large (46-bp) indel, are apparently uncommon in teleost fish control region sequences reported to date. The common occurrence of tandem arrays in fish control regions could be related to a stable secondary structure. Based on the frequency distribution of tandem repeat units, no significant geographic heterogeneity (P=0.904) among eight populations of Japanese Spanish mackerel was detected by the exact test. Long period of larval stage, strong dispersal ability of adults and long migrations might be responsible for the high genetic connections among populations and reducing the genetic heterogeneity.
Genetic structure of Japanese Spanish mackerel (Scomberomorus niphonius) in the East China Sea and Yellow Sea inferred from AFLP data
BN Shui, ZQ Han, TX Gao, ZQ Miao
African Journal of Biotechnology , 2008,
Abstract: The population genetic structure of Japanese Spanish mackerel (Scomberomorus niphonius) in the East China Sea and Yellow Sea was analyzed using amplified fragment length polymorphism (AFLP). A total of 247 putative loci were detected by four primer combinations among 83 individuals of Japanese Spanish mackerel collected from Ganyu, Ningbo, Wenzhou, Cheju Island and Nagasaki, 129 of which were polymorphic (52.23%). The proportion of polymorphic loci and Nei’s genetic diversity for five populations ranged from 38.54% (Ganyu) to 45.70% (Nagasaki), and from 0.0808 (Cheju Island) to 0.0984 (Nagasaki). AMOVA analysis and pairwise FST revealed significant genetic differentiation among five populations. The UPGMA tree revealed the significant geographic structure in this species. Considering the high hydrological connectivity of this region and the species pelagic life history, retention of larvae, different migration route and different spawning season may be responsible for the significant genetic differentiation among populations in the East China Sea and Yellow Sea.
Phylogeography and historical demography of the Pacific Sierra mackerel (Scomberomorus sierra) in the Eastern Pacific
Mónica López, Manuel Alcocer, Píndaro Jaimes
BMC Genetics , 2010, DOI: 10.1186/1471-2156-11-34
Abstract: Samples collected from the Eastern Pacific, including the areas of main abundance of the species, presented high levels of mtDNA genetic diversity and a highly significant divergence. At least two genetically discrete groups were detected in the northern (Sinaloa) and central areas (Oaxaca and Chiapas) of the species range, exhibiting slight genetic differences with respect to the samples collected in the southern region (Peru), together with a "chaotic genetic patchiness" pattern of differentiation and no evidence of isolation by distance. Historical demographic parameters supported the occurrence of past population expansions, whereas the divergence times between populations coincided with the occurrence of glacial maxima some 220 000 years ago.The population genetic structure detected for the Pacific Sierra mackerel is associated with a limited dispersal between the main abundance areas that are usually linked to the spawning sites of the species. Population expansions have coincided with glacial-interglacial episodes in the Pleistocene, but they may also be related to the increase in the SST and with upwelling areas in the EEP since the early Pleistocene.The definition of factors that determine genetic divergence in populations from marine ecosystems has become a subject of interest for evolutionary biology and conservation. The subdivision of populations in an apparently homogeneous environment has been found to be complex [1]. Evolutionary divergence processes in the marine realm are thought to have minor effects on species with long-lived pelagic eggs and larvae, and/or on those that have a significant capacity to disperse through migrations, as well as large effective population sizes. For many marine species, dispersal mediated by larval drift promotes their range expansion as well as a mixing of populations [2]. Likewise, the effects of genetic drift may be imperceptible in species with large effective population sizes [3]. Consequently, most marine specie
The use of three anaesthetics for handling spotted rose snapper Lutjanus guttatus (Pisces, Lutjanidae) broodstock
Ibarra-Zatarain,Zohar; Ibarra-Castro,Leonardo; Alvarez-Lajonchère,Luis; García Aguilar,Noemi; Sánchez-Téllez,Juan Luis;
Revista de biología marina y oceanografía , 2011, DOI: 10.4067/S0718-19572011000300016
Abstract: benzocaine, 2-phenoxyethanol and ms-222 were tested as anaesthetics for several handling procedures with spotted rose snapper lutjanus guttatus broodstock. significant differences in time for induction and recovery were found with specific doses, as well as a direct correlation between the dose and the induction time. each procedure demanded specific anaesthesia levels where the stage of deep anaesthesia should not be surpassed. the most effective agent for inducing deep anaesthesia was ms-222, with the least amount of time required for induction and recovery when using 100 mg l-1. it was followed by 250 μl l-1 of 2-phenoxyethanol, which was less costly.
Population characteristics of spotted rose snapper lutjanus guttatus caught as shrimp bycatch in the gulf of California
González-Ochoa,Oscar A; López-Martínez,Juana; Hernández-Saavedra,Norma Yolanda;
Interciencia , 2009,
Abstract: there are limited population biology studies of the spotted rose snapper lutjanus guttatus. adults of this highly valued commercial species are fished with gillnets and hook-and-line, while juveniles are caught as shrimp bycatch and usually discarded. the effects of this practice have not been studied. as a first step, this study assessed some population parameters of juvenile snapper caught by the gulf of california shrimp fishery. we looked for early growth stages and determined by the least squares method the weight to standard length relationship as w= 0.000092, sl3.0509. length frequency distributions were constructed; using the elefan i method, von bertalanffy growth parameters were found to be l¥= 515mm (standard length) and k= 0.13. natural mortality (m= 0.35) was estimated from pauly?s empirical and ralston equations; and total mortality was calculated by the catch curve equation. the recruitment pattern extended throughout the year, with spring and summer peaks. the sex ratio was 1:1 and the length at capture was 80mm (standard length). with an apparently high fishing mortality levels, it is recommended that abundance and distribution studies be performed to determine the impact of shrimp fishing on this population.
Composición y análisis taxonómico de la íctiofauna del golfo de Tribugá, Pacífico norte de Colombia
Tobón-López,Alexander; Rubio,Efraín A; Giraldo,Alan;
Latin american journal of aquatic research , 2008,
Abstract: a taxonomical and structural analysis of the fish community in the gulf of tribugá, northern colombian pacific, was done based on information from different artisanal fishing techniques (hand lines, long lines, gillnets, trawl nets, harpoons, throw nets) and visual identification by scuba diving. as many as 191 species were registered, belonging to 21 orders and 68 families. hand lines (71 species) and long lines (41 species) were used systematically and consecutively throughout the sampling period. therefore, the catch analysis was carried out using only the fish caught with these two techniques. the most abundant families were carangidae (8.9%), serranidae (6.3%), and lutjanidae (4.2%). these families, along with scombridae and ophidiidae, contributed the most in number, biomass, commercial importance, and human consumption by the local communities. the top ten species captured during sampling were the skipjack tuna (euthynnus lineatus), sierra mackerel (scomberomorus sierra), gulf coney (epinephelus acanthistius), clark's brotula (brotula clarkae), spotted rose snapper (lutjanus guttatus), yellow snapper (lutjanus argentiventris), almaco jack (serióla rivoliana), pacific crevalle jack (caranx caninus), green jack (caranx caballus), and purse-eyed scad {selar crumenophthalmus). the mocosa ruff, schedophilus haedrichi (centrolophidae), is reported for first time in the northern colombian pacific.
Estudios sobre el manejo e incubación de huevos del pargo flamenco Lutjanus guttatus (Pisces, Lutjanidae) Studies in egg handling and incubation in the spotted rose snapper Lutjanus guttatus (Pisces Lutjanidae)
Leonardo Ibarra-Castro,Landy Elizabeth Mu?oz-Meza,Luis álvarez-Lajonchère
Hidrobiológica , 2012,
Abstract: La manipulación y la incubación de huevos de peces son procedimientos simples pero importantes en las tecnologías de producción de juveniles. Para determinar prácticas apropiadas de manejo y de incubación de los huevos del pargo flamenco Lutjanus guttatus (Steindachner, 1869), se realizaron tres experimentos en tanques cilindro-cónicos de fibra de vidrio de 100 L. Los huevos fueron incubados con y sin flujo de agua (30%/h), a dos densidades (250 huevos/L y 1000 huevos/L) y con o sin tratamiento profiláctico de formalina 10 ppm por una hora previo a la incubación. Los porcentajes de eclosión total y larvas vivas normales (larvas viables) al momento de la eclosión no fueron diferentes significativamente entre los tratamientos con flujo y sin flujo. Mientras que los porcentajes de larvas viables al momento de la eclosión y a las 48 h post-eclosión mostraron significativamente mejores resultados en el tratamiento sin flujo de agua. En la incubación a dos densidades todos los índices analizados fueron significativamente mejores en la densidad de 250 huevos/L, excepto en larvas viables a las 48 h post-eclosión. Los huevos con y sin tratamiento profiláctico, no presentaron diferencias significativas para todas las variables de supervivencia al momento de la eclosión y a las 48 h post-eclosión. La longitud total de larvas fue diferente significativamente entre cada uno de los tratamientos al momento de la eclosión y a las 48 h, excepto en la incubación sin flujo de agua. Las larvas de mayor tama o se obtuvieron en el experimento con sobre tratamiento profiláctico. Egg handling and incubation are short but important procedures in juvenile fish production technologies. To determine appropriate practices for egg handling and incubation in the spotted rose snapper Lutjanus guttatus (Steindachner, 1969), three experiments were carried out in 100-L fiberglass conical cylinder tanks. Eggs were incubated with and without water flow (30% volume/h), at two densities (250 eggs/L and 1000 eggs/L), and with and without formaldehyde 10-ppm prophylactic treatment for 1-h prior to incubation. Total hatching and larvae survival percentages were not significantly different between the treatments with and without water flow, while results for larvae survival at hatching time and 48 h post-hatch stage were significantly better without water flow. For incubation at two different densities, all examined performance indexes were significantly better at the lower density, except for larvae survival at 48 h after hatching. The eggs with and without prophylactic treatment were not signi
Hormone-induced spawning of wild and captive-grown spotted rose snapper Lutjanus guttatus using carp pituitary suspension and human chorionic gonadotropin
Boza-Abarca, J;Valverde-Chavarría, S;Calvo-Vargas, E;Ramírez-Alvarado, M;Rodríguez-Gómez, E;
Ciencias marinas , 2011,
Abstract: hormone-induced spawning of the spotted rose snapper lutjanus guttatus was studied using wild and cage-grown fish. carp pituitary suspension (cps) and human chorionic gonadotropin (hcg) were assessed. wild females (0.7-2.1 kg body weight (bw), n = 18) were collected by hook and line in the gulf of nicoya, costa rica, to induce final maturation and ovulation in the laboratory. in the first experiment, five doses of cps were evaluated and spawning was only observed at the higher doses (4.0 and 4.5 mg cps kg-1 bw); the doses used were lower than for other species under similar conditions. in the second experiment, cps and hcg protocols were compared using cage-grown broodstock (n = 30 females, 462-995 g; n = 60 males, 400-600 g); egg production was more consistent for the hcg protocol. in the third experiment, cage-grown fish (n = 12 females, 368-977 g; n = 24 males, 400-600 g) were used to assess the female response to hcg and the fertility of the spawned eggs; two successive injections of different hcg doses were tested. the results confirm that two successive doses of 900 and 700 iu hcg kg-1 bw result in the highest number of eggs spawned and the best fertilization rates.
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