The seasonal entrance of Penaeus setiferus and Penaeus duorarum postlarvae into Términos Lagoon, Campeche, México

This study establishes the season for the immigration (recruitment) of Penaeus setiferus and P. duorarum postlarvae into Términos Lagoon, México, as well as the hydrological conditions that occur during this event. The abundance of postlarvae of both species was used to infer the reproductive period for each species. The zooplankton collection was carried out monthly for three years. The nets used were 50 cm in diameter, 1.5 m in length and 505 μm mesh size, and temperature and salinity were measured with an YSI. The fluvial discharges were taken from Comisión Nacional del Agua (CONAGUA). The harmonic pattern variation (HPV) was analyzed for each variable (density of postlarvae, salinity, temperature and fluvial discharge). A cycle was analyzed and divided into two episodes (rise and descent) to estimate the HPV of each postlarval species. The entrance of both postlarval species starts from June to September, with higher density in August, which decreases from October to May, with the lowest density in March. The first episode was established from June to August and the second episode in September. During the first episode the hydrological conditions were: high salinity (34), a warm temperature (30ºC) and low accumulated fluvial discharge (2,828 m3 s-1), while, in the second, they were low salinity (28), a moderately warm temperature (29ºC) and high accumulated fluvial discharge (3,934 m3 s-1).

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Population biology of shrimp Macrobrachium jelskii (Miers, 1778) (Decapoda, Palaemonoidea) at the Grande River at northwest of the state of Minas Gerais, Brazil

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2012005000044 ◽

2012 ◽

Vol 24 (3) ◽

pp. 266-275 ◽

Cited By ~ 12

Author(s):

Samara de Paiva Barros-Alves ◽

Ariádine Cristine Almeida ◽

Vivian Fransozo ◽

Douglas Fernandes Rodrigues Alves ◽

José Carlos da Silva ◽

...

Keyword(s):

Sex Ratio ◽

Frequency Distribution ◽

Population Biology ◽

Abiotic Factors ◽

Mesh Size ◽

Minas Gerais ◽

Reproductive Period ◽

Length Frequency Distribution ◽

Length Frequency ◽

Monthly Basis

AIM: The population biology of the freshwater shrimp Macrobrachium jelskii was investigated here emphasizing the length-frequency distribution, sex ratio, reproductive period and juvenile recruitment. In addition, the abundance of individuals was correlated with the abiotic factors. METHODS: Samples were collected on a monthly basis from July 2005 to June 2007 along the river margin in shallow water of Grande River, at Planura region, State of Minas Gerais, Brazil (20º 09' S and 48º 40' W), using a trawl net (1.0 mm mesh size, and 2.0 m × 0.5 m wide). The fishing gear was handled by two people along the marginal vegetation of the Grande River in a course of 100 m, covered for one hour. In the laboratory, the specimens were identified, measured and sexed. RESULTS: A total of 2,789 specimens was analyzed, which corresponded to 1,126 males (549 juveniles and 577 adults) and 1,663 females (1,093 juveniles, 423 adults non-ovigerous and 147 ovigerous). The sex ratio differed significantly in favor of the females of M. jelskii (1:1.48; χ² = 103.95; p < 0.0001). The mean size of carapace length (CL) of females (6.32 ± 1.84 mm CL) was statistically higher than of males (5.50 ± 1.07 mm CL) (p < 0.001). The length-frequency distribution of the specimens revealed an unimodal pattern and non-normal distribution for males and females (W = 0.945; p < 0.01). No significant relationship between the abundance of M. jelskii and the environmental variables was observed (p = 0.799). CONCLUSION: The presence of ovigerous females and juveniles in the population suggests a continuous reproduction pattern and recruitment for M. jelskii at Planura region.

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A Method For Obtaining Metaphase Chromosome Spreads From Marine Shrimp With Notes On The Karyotypes Of: Penaeus aztecus, Penaeus setiferus, and Penaeus duorarum

Proceedings of the annual meeting - World Mariculture Society ◽

10.1111/j.1749-7345.1976.tb00073.x ◽

2009 ◽

Vol 7 (1-4) ◽

pp. 327-332 ◽

Cited By ~ 6

Author(s):

D. J. Milligan

Keyword(s):

Metaphase Chromosome ◽

Penaeus Aztecus ◽

Penaeus Setiferus ◽

Marine Shrimp ◽

Penaeus Duorarum

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Population structure and reproductive behavior of Sinaloa cichlid Cichlasoma beani (Jordan, 1889) in a tropical reservoir

Neotropical Ichthyology ◽

10.1590/s1679-62252011005000035 ◽

2011 ◽

Vol 9 (3) ◽

pp. 593-599 ◽

Cited By ~ 2

Author(s):

Melgen A. García-Lizárraga ◽

Francisco Enrique Soto-Franco ◽

Javier Marcial de Jesús Ruiz Velazco-Arce ◽

José Iván Velázquez-Abunader ◽

Jorge Saúl Ramírez-Pérez ◽

...

Keyword(s):

Population Structure ◽

Sex Ratio ◽

Multinomial Distribution ◽

Mesh Size ◽

Condition Index ◽

Reproductive Period ◽

Tropical Reservoir ◽

Timing Of Reproduction ◽

First Maturity ◽

Size At First Maturity

The population structure and reproductive condition of the Sinaloa cichlid Cichlasoma beani from samples obtained from June 2000 to July 2001 were determined. Samples in the first week each month from the largest trader of tilapia in the Aguamilpa Reservoir in Mexico and were caught in gillnets (9.6 and 11.4 cm stretch-mesh size). Of 596 specimens, there were 427 males and 169 females; monthly sex ratio, frequency of lengths by the multinomial distribution, timing of reproduction, condition index, and size at first maturity was determined. Differences in the sex ratio and monthly totals were significant, favoring males, except for September 2000 and March 2001. From one (August 2000) to three modal groups (July 2000 and June 2001) were identified by size. There were no significant differences in standard length weight relationships by sex, which indicated that a shared model for both genders is appropriate, and isometric growth was detected. Based on the proportion of mature and partially matures fish, the main reproductive period was April through June; size at first maturity was 18.9 cm. Water temperature was not significantly related to the percentage of mature and partially matures Sinaloa cichlids or spawning. These findings provide information for regulating the Cichlasoma beani fishery in this region such minimum legal size and non-fishing period.

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Short term changes in zooplankton community during the summer-autumn transition in the open NW Mediterranean Sea: species composition, abundance and diversity

Biogeosciences ◽

10.5194/bg-5-1765-2008 ◽

2008 ◽

Vol 5 (6) ◽

pp. 1765-1782 ◽

Cited By ~ 28

Author(s):

V. Raybaud ◽

P. Nival ◽

L. Mousseau ◽

A. Gubanova ◽

D. Altukhov ◽

...

Keyword(s):

Species Richness ◽

Species Composition ◽

Zooplankton Community ◽

Mesh Size ◽

Temporal Variations ◽

Water Masses ◽

Short Term ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water

Abstract. Short term changes in zooplankton community were investigated at a fixed station in offshore waters of the Ligurian Sea (DYNAPROC 2 cruise, September–October 2004). Mesozooplankton were sampled with vertical WP-II hauls (200 μm mesh-size) and large mesozooplankton, macrozooplankton and micronekton with a BIONESS multinet sampler (500 μm mesh-size). Temporal variations of total biomass, species composition and abundance of major taxa were studied. Intrusions of low salinity water masses were observed two times during the cruise. The first one, which was the most intense, was associated with changes in zooplankton community composition. Among copepods, the abundance of Calocalanus, Euchaeta, Heterorhabdus, Mesocalanus, Nannocalanus, Neocalanus, Pleuromammaand also calanoid copepodites increased markedly. Among non-copepod taxa, only small ostracods abundance increased. After this low salinity event, abundance of all taxa nearly returned to their initial values. The influence of salinity on each zooplankton taxon was confirmed by a statistical analysis (Perry's method). The Shannon diversity index, Pielou evenness and species richness were used to describe temporal variations of large copepod (>500 μm) diversity. The Shannon index and Pielou evenness decreased at the beginning of the low salinity water intrusions, but not species richness. We suggest that low salinity water masses contained its own zooplankton community and passed through the sampling area, thus causing a replacement of the zooplankton population.

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Reproduction Under Stress: Acute Effect of Low Salinities and Heat Waves on Reproductive Cycle of Four Ecologically and Commercially Important Bivalves

Frontiers in Marine Science ◽

10.3389/fmars.2021.685282 ◽

2021 ◽

Vol 8 ◽

Author(s):

Elsa Vázquez ◽

Sarah A. Woodin ◽

David S. Wethey ◽

Laura G. Peteiro ◽

Celia Olabarria

Keyword(s):

Acute Stress ◽

Heat Waves ◽

Gonad Development ◽

Acute Effect ◽

Ruditapes Philippinarum ◽

Reproductive Period ◽

Ruditapes Decussatus ◽

Low Salinity ◽

Acute Response ◽

The Impact

The impacts of climate change on the structure and functioning of estuaries is a major focus of concern, even more when the affected species support important fisheries as the bivalves Ruditapes decussatus, Ruditapes philippinarum, Venerupis corrugata, and Cerastoderma edule in Europe. Their reproductive performance, in the context of climate stressors, had not been investigated so far. Our objective was to experimentally evaluate acute stress effects over gonad development after 6 days of low salinity stress in autumn, winter and spring as well as 4 days of heatwave stress during emersion in summer. These are the most probable extreme events that bivalves should face in our latitudes. Four different salinity ramps (5–20, 10–25, 15–30, 30–30) were created during simulated tidal cycles in mesocosms for the low salinity experiments. Also four sediment heatwaves at emersion (20–20, 20–27, 20–32, 20–37°C) were done during simulated tidal cycle. Both low salinity and heatwave stresses over such short periods compromised reproduction; the acute response was species-specific and varied with the time of the year, and therefore, with the stage of the gametogenic cycle. In December, during sexual resting and the beginning of gametogenesis, a delay in gametogenesis at lower salinities was recorded in the four species. However, at the peak of the reproductive period (March and May), different responses were observed: abnormal oocytes in R. decussatus and resorption of gametes with haemocytic infiltration in R. philippinarum and V. corrugata. Likewise sediment temperatures higher than 32°C provoked gonadal resorption and severe haemocytic invasion in V. corrugata, R. decussatus, and C. edule but had no effect in R. philippinarum. These responses to both environmental stressors might be related to the allocation of energy from reproduction toward defense and repair mechanisms to ensure survival. Contrastingly, low salinities triggered massive spawning in C. edule that could lead to a mismatch between the presence of larvae and phytoplankton, causing potentially starvation and thus reducing recruitment success. Reproduction of theses bivalves would be compromised if low salinity episodes in winter and spring, even for short periods of time such as those in these experiments, are followed by a heatwave in summer. Furthermore the impact would be magnified if this situation happens during consecutive years preventing replenishment of the shellfish beds.

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Short term changes in zooplankton community during the summer-autumn transition in the open NW Mediterranean Sea: species composition, abundance and diversity

Biogeosciences Discussions ◽

10.5194/bgd-5-2237-2008 ◽

2008 ◽

Vol 5 (3) ◽

pp. 2237-2278 ◽

Cited By ~ 4

Author(s):

V. Raybaud ◽

P. Nival ◽

L. Mousseau ◽

A. Gubanova ◽

D. Altukhov ◽

...

Keyword(s):

Species Richness ◽

Species Composition ◽

Zooplankton Community ◽

Mesh Size ◽

Temporal Variations ◽

Water Masses ◽

Short Term ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water

Abstract. Short term changes in zooplankton community were investigated at a fixed station in offshore waters of the Ligurian Sea (Dynaproc 2 cruise, September–October 2004). Mesozooplankton was sampled with vertical WP2 hauls (200 µm mesh-size) and large mesozooplankton, macrozooplankton and micronekton with a BIONESS multinet sampler (500 µm mesh-size). Temporal variations of total biomass, species composition and abundance of major taxa were studied. Intrusions of low salinity water masses were observed two times during the cruise. The first one, which was the most important, was associated with changes in zooplankton community composition. Among copepods, the abundance of Calocalanus, Euchaeta, Heterorhabdus, Mesocalanus, Nannocalanus, Neocalanus, Pleuromamma and also calanoid copepodites increased markedly. Among non-copepod taxa, only small ostracods abundance increased. After this low salinity event, abundance of all taxa nearly returned to their initial values. The influence of salinity on each zooplankton taxon was confirmed by a statistical analysis (Perry's method). Shannon diversity index, Pielou evenness and species richness were used to describe temporal variations of large copepod (>500 µm) diversity. Shannon index and Pielou evenness decreased at the beginning of the low salinity water intrusions, but not species richness. We suggest that low salinity water masses contained its own zooplankton community and passed through the sampling area, thus causing the replacement of zooplankton population.

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Thrombophilia and risk of VTE recurrence according to the age at the time of first VTE manifestation

VASA ◽

10.1024/0301-1526/a000447 ◽

2015 ◽

Vol 44 (4) ◽

pp. 313-323 ◽

Cited By ~ 6

Author(s):

Lea Weingarz ◽

Marc Schindewolf ◽

Jan Schwonberg ◽

Carola Hecking ◽

Zsuzsanna Wolf ◽

...

Keyword(s):

Factor V Leiden ◽

Cox Proportional Hazards ◽

First Episode ◽

Factor V ◽

Factor V Leiden Mutation ◽

Younger Patients ◽

Risk Of Recurrence ◽

G20210a Mutation ◽

Increased Risk ◽

The Impact

Abstract. Background: Whether screening for thrombophilia is useful for patients after a first episode of venous thromboembolism (VTE) is a controversial issue. However, the impact of thrombophilia on the risk of recurrence may vary depending on the patient’s age at the time of the first VTE. Patients and methods: Of 1221 VTE patients (42 % males) registered in the MAISTHRO (MAin-ISar-THROmbosis) registry, 261 experienced VTE recurrence during a 5-year follow-up after the discontinuation of anticoagulant therapy. Results: Thrombophilia was more common among patients with VTE recurrence than those without (58.6 % vs. 50.3 %; p = 0.017). Stratifying patients by the age at the time of their initial VTE, Cox proportional hazards analyses adjusted for age, sex and the presence or absence of established risk factors revealed a heterozygous prothrombin (PT) G20210A mutation (hazard ratio (HR) 2.65; 95 %-confidence interval (CI) 1.71 - 4.12; p < 0.001), homozygosity/double heterozygosity for the factor V Leiden and/or PT mutation (HR 2.35; 95 %-CI 1.09 - 5.07, p = 0.030), and an antithrombin deficiency (HR 2.12; 95 %-CI 1.12 - 4.10; p = 0.021) to predict recurrent VTE in patients aged 40 years or older, whereas lupus anticoagulants (HR 3.05; 95%-CI 1.40 - 6.66; p = 0.005) increased the risk of recurrence in younger patients. Subgroup analyses revealed an increased risk of recurrence for a heterozygous factor V Leiden mutation only in young females without hormonal treatment whereas the predictive value of a heterozygous PT mutation was restricted to males over the age of 40 years. Conclusions: Our data do not support a preference of younger patients for thrombophilia testing after a first venous thromboembolic event.

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Rorschach Characteristics and Comparison of First-Episode Psychotic Patients in Finland and Spain

Rorschachiana Journal of the International Society for the Rorschach ◽

10.1027/1192-5604.26.1.63 ◽

2004 ◽

Vol 26 (1) ◽

pp. 63-84 ◽

Cited By ~ 4

Author(s):

Outi Kalla ◽

Jarl Wahlström ◽

Jukka Aaltonen ◽

Juha Holma ◽

Pentti Tuimala ◽

...

Keyword(s):

First Episode ◽

Dsm Iv ◽

Troubles Psychotiques ◽

Premier Épisode Psychotique ◽

Phase Aiguë ◽

Cette Question ◽

Donne Lieu ◽

Système Intégré ◽

Relations Interpersonnelles

Identifier avec précision les troubles schizophréniques a toujours été un problème complexe et controversé. Les caractéristiques psychologiques de la schizophrénie ont donné lieu à un volume considérable de travaux et de débats. Ces dernières années sont apparus un nombre croissant d'articles portant sur les différences et similitudes des manifestations de la psychose selon les cultures, partant de l'idée que les caractéristiques de personnalité nationales pourraient contribuer aux tableaux psychopathologiques. Le but premier de cette étude est de mieux comprendre les troubles psychotiques par l'investigation de la structure de personnalité et du fonctionnement de patients faisant un premier épisode psychotique. Le second objectif est de décrire les différences et similitudes observées dans les réponses au Rorschach de patients finlandais et espagnols afin de mettre en évidence des caractéristiques nationales et de contribuer ainsi à la recherche Rorschach interculturelle. Ont été inclus 41 protocoles de patients finlandais hospitalisés de manière consécutive pour premier épisode psychotique, et 32 en Espagne. Le travail a porté sur un certain nombre d'indicateurs de difficultés d'ajustement tirés du résumé formel du Rorschach en Système intégré ( Weiner & Exner, 1991 ). Tous les patients avaient été diagnostiqués comme schizophrènes ou souffrant d'autres troubles fonctionnels psychotiques non affectifs selon le DSM-IV. Les Rorschach ont été administrés en Système intégré aussitôt que possible après leur admission mais après la phase aiguë. La comparaison des groupes finlandais et espagnol, loin de montrer des différences significatives, étaient similaires sur beaucoup de points. Ces résultats confirment des données déjà bien établies sur les structures et mécanismes des patients psychotiques, mais ils en interrogent d'autres. Les patients obtiennent plus de styles ambiéquaux et moins d'introversifs que prévu. Beaucoup d'entre eux manquent de compétences sociales, d'intérêt pour les relations interpersonnelles et semblent avoir une vie sociale insatisfaisante. On observe des signes de difficultés dans le contrôle émotionnel et de modulation des affects, des traits dépressifs, une détresse émotionnelle, et peu de capacités de coping. Les résultats soulignent la notion que les problèmes affectifs et les traits dépressifs devraient être considérés comme un élément important dans un premier épisode psychotique, et ils confirment la présence de déficits cognitifs survenants tôt dans l'histoire d'un trouble psychotique. On a rencontré moins de dysfonctionnements idéationnels que prévu. Les deux groupes de patients se différenciaient sur certaines variables Rorschach, en particulier celles qui concernent la perception de soi. Les patients finlandais sont plus souvent centrés sur eux-mêmes de faç on excessive, plus préoccupés d'eux-mêmes et plus enclins M l'introspection. La majorité des patients espagnols manifestent un sentiment de valeur de soi négatif. Ils disposent de moins de ressources et ont plus souvent des déficits en capacité de coping. En admettant que ces résultats sont dus à des différences dans les caractéristiques de personnalité des patients psychotiques en Finlande et en Espagne, plutôt que des différences nationales dans la manifestation au Rorschach de structures de personnalité en fait identiques, alors ces données pourraient bien nous permettre de repérer des différences interculturelles de personnalité. Toutefois, l'impact des facteurs culturels est difficile M évaluer, surtout s'agissant d'une psychopathologie aussi sévère que la psychose, et la seule faç on d'avancer dans la compréhension de cette question serait de recueillir plus de données Rorschach interculturelles sur des patients psychotiques.

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