Relation Between Egg Size, Growth, and Natural Mortality of Larval Fish

A set of density-dependent growth and survivorship equations is derived from evidence that the instantaneous death rate in the sea is inversely proportional to particle size. The survivorship equation reproduces several well-known phenomena observed in fish populations. It predicts: 1) that winter and spring spawning species ought to produce larger eggs than summer spawners, 2) that it is advantageous for species that spawn in batches to produce progressively smaller eggs in spring and summer, and 3) that the death rate of a cohort of fish should decrease continuously as the survivors grow and approach the critical size.The biological basis for the observed variation in the size of pelagic fish eggs and larvae is thought to be due primarily to trophic relations within the pelagic community. It is suggested from what is known of the relative abundance and foraging capabilities of different sized particles, that the survival rates of larval and juvenile fish should increase as they grow and occupy a progressively higher position in the food chain.

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Variability and capture efficiency of bongo and Tucker trawl samplers in the collection of ichthyoplankton and other macrozooplankton

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f96-347 ◽

1997 ◽

Vol 54 (4) ◽

pp. 765-773 ◽

Cited By ~ 21

Author(s):

P Pepin ◽

T H Shears

Keyword(s):

Larval Fish ◽

Fish Larvae ◽

Sample Volume ◽

Capture Efficiency ◽

Fish Eggs ◽

Sample Mean ◽

Sampling Variability ◽

Wide Range ◽

Eggs And Larvae ◽

Fish Eggs And Larvae

We examined the sampling variability and capture efficiency of bongo nets and a modified Tucker trawl used in the sampling of ichthyoplankton and other macrozooplankton by taking seven replicate samples at each of two stations on two separate occasions. Sample variance was highly significantly related to sample mean for all major taxonomic categories (i.e., fish eggs, fish larvae, crustaceans, and medusae-chaetognaths). Sampling variability of the bongo nets was significantly greater than that of the Tucker trawl for both fish eggs and larvae. Sampling variability of macrozooplankton was significantly greater than that of ichthyoplankton. For larval fish of 5 mm or less, bongo nets generally yielded higher estimates of abundance than the Tucker trawl and the reverse was true for lengths above 10 mm, but there was a significant influence of species-specific morphological characters. The large sample volume of the Tucker trawl relative to the bongo nets resulted in significantly higher estimates of species diversity for fish eggs and larvae but not for crustaceans or medusae. Although bongo and Tucker samplers are efficient at catching a wide range of sizes of larval fish, the latter's lower variability may make it a more effective sampler.

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Chordata: Fish eggs and larvae

10.1093/oso/9780199233267.003.0041 ◽

2017 ◽

Author(s):

Peter Munk ◽

Jørgen G. Nielsen

Keyword(s):

Life Cycle ◽

Tree Of Life ◽

Fish Eggs ◽

General Morphology ◽

Family Level ◽

Eggs And Larvae ◽

Fish Eggs And Larvae

This chapter describes the taxonomy of fish eggs and larvae. Most fish eggs and larvae are planktonic, and are commonly found in plankton net tows. Collectively these fish stages are referred to as ichthyoplankton. The chapter covers their life cycle, ecology, and general morphology. It includes a section that indicates the systematic placement of the taxon described within the tree of life, and lists the key marine representative illustrated in the chapter (usually to genus or family level). This section also provides information on the taxonomic authorities responsible for the classification adopted, recent changes which might have occurred, and lists relevant taxonomic sources.

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SAT0316 ANTI-PM/SCL ANTIBODIES IN SYSTEMIC SCLEROSIS: CLINICAL ASSOCIATIONS IN THE RESCLE COHORT

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.3304 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 1103.1-1104

Author(s):

N. Iniesta-Arandia ◽

G. Espinosa ◽

A. Guillen del Castillo ◽

C. Tolosa ◽

G. M. Lledó ◽

...

Keyword(s):

Systemic Sclerosis ◽

Survival Data ◽

Death Rate ◽

Administrative Support ◽

Medical Science ◽

Survival Rates ◽

Clinical Manifestations ◽

Study Group ◽

Allergy Immunol ◽

Science Service

Background:Anti-PM/Scl antibodies are associated to systemic sclerosis (SSc) but are not specific to SSc. The true prevalence of anti-PM/Scl antibodies in SSc is unknown, ranging from 2.5% to 12.5%. An association between anti-PM/Scl antibodies with muscular involvement, pulmonary fibrosis, calcinosis, and a relatively benign prognosis have been described.Objectives:To compare the clinical manifestations and prognosis of SSc patients according the presence of anti-PM/Scl antibodies in the cohort of RESCLE (Spanish Scleroderma Registry).Methods:From the Spanish Scleroderma Study Group database, we selected patients in whom anti-PM/Scl antibodies had been tested. We compared demographic features, clinical manifestations, laboratory characteristics, and survival data between patients according the anti-PM/Scl antibodies status.Results:72 out of 947 (7%) patients tested positive for anti-PM/Scl antibodies. As presenting SSc manifestations, patients with anti-PM/Scl antibodies had higher prevalence of puffy fingers (11% versus 2%; p=0.002) and arthralgias (11% versus 4%; p=0.03), and lower prevalence of Raynaud’s phenomenon (65% versus 82%, p=0.002). Regarding cumulative manifestations, myositis (51% versus 15%; p<0.001), arthritis (43% versus 22%; p=0.001), and interstitial lung disease (ILD) (60% versus 45%, p=0.014) were more prevalent in patients with anti-PM/Scl antibodies. In fact, those patients with anti-Pm/Scl antibodies presented with FVC (77.4% ± 23.1% versus 85.8% ± 23,1%; p=0.006) and more severe ILD defined as FVC <70% (41% versus 24%; p=0.004). Death rate was similar in patients with and without PM/Scl antibodies (18% versus 17%; p=0.871).We did not find differences in terms of death rate nor in the causes of death (SSc and non-SSc related) according to the anti-PM/Scl antibodies profile.The 5- and 10-years survival rates of patients with anti-PM/Scl antibodies were 91% and 82% respectively, without differences with those without these antibodies (93% and 85%, respectively).Conclusion:In Spanish SSc patients, the presence of anti-PM/Scl antibodies confer a distinctive clinical profile. However, anti-PM/Scl antibodies do not play a role in the prognosis of these patients.References:[1]Stochmal A, Czuwara J, Trojanowska M, Rudnicka L. Antinuclear antibodies in systemic sclerosis: an update. Clin Rev Allergy Immunol 2020;58(1):40-51. doi: 10.1007/s12016-018-8718-8.Acknowledgments:We gratefully acknowledge all investigators who are part of the RESCLE Registry. We also thank the RESCLE Registry Coordinating Centre, S&H Medical Science Service, for their quality control data, logistic and administrative support and Prof. Salvador Ortiz, Universidad Autónoma de Madrid and Statistical Advisor S&H Medical Science Service for the statistical analysis of the data presented in this paper.Disclosure of InterestsNerea Iniesta-Arandia: None declared, Gerard Espinosa Speakers bureau: Glaxo-Smith-Kline, Janssen, Boehringer, Rovi, Alfredo Guillen del Castillo: None declared, Carles Tolosa Consultant of: Actelion pharmaceuticals, GSK, MSD., Gema Maria Lledó: None declared, Dolores Colunga Argüelles Consultant of: Actelion pharmaceuticals, GSK, MSD., Cristina González-Echávarri: None declared, Luis Sáez-Comet: None declared, Norberto Ortego: None declared, Jose Antonio Vargas-Hitos: None declared, Manuel Rubio-Rivas: None declared, Mayka Freire: None declared, Juan José Rios: None declared, Monica Rodriguez-Carballeira: None declared, Luis Trapiella Martínez: None declared, Vicent Fonollosa Pla Speakers bureau: Actelion, Carmen Pilar Simeón-Aznar Consultant of: Actelion pharmaceuticals, GSK, MSD., on behalf of RESCLE Investigators, Autoimmune Diseases Study Group (GEAS): None declared

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Feeding of the Brycon cephalus, Triportheus elongatus and Semaprochilodus insignis (osteichthyes, characiformes) larvae in Solimões/Amazonas River and floodplain areas.

Acta Amazonica ◽

10.1590/1809-43922002323515 ◽

2002 ◽

Vol 32 (3) ◽

pp. 499-499 ◽

Cited By ~ 13

Author(s):

Rosseval Galdino LEITE ◽

Carlos A.R.M. ARAUJO-LIMA

Keyword(s):

Food Item ◽

Prey Size ◽

Larval Fish ◽

Fish Larvae ◽

Trophic Relations ◽

Fish Feeding ◽

Important Species ◽

Flooded Forests ◽

Commercially Important

Information on larval fish feeding is essential for understanding their trophic relations, including the management in conditions totally or partially controlled by humans. An experiment was designed to evaluate the larval diets of three commercially important species. Four varzea-lakes and the adjacent river were sampled with bongo and hand nets from January 1993 to November 1995. Larval diets were evaluated by length-classes and capture sites, and were tested by two factor ANOVA. The larvae were feeding in all habitats, except in the flooded forests. The three species had different diets, which varied with their length and lake. The rotifers were the main initial food item of the three species, replaced by fish larvae in Brycon cephalus, cladocerans in Triportheus elongatus and detritus in Semaprochilodus insignis. The increase of the ingestion limit, as the larvae grew, was higher than the increase in the consumed prey size for the three species.

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Numerical studies on the influence of the variations of the Kuroshio Path on the transport of fish eggs and larvae

GeoJournal ◽

10.1007/bf02626376 ◽

1988 ◽

Vol 16 (1) ◽

pp. 113-117 ◽

Cited By ~ 2

Author(s):

Takashige Sugimoto ◽

Masato Kobayashi

Keyword(s):

Fish Eggs ◽

Kuroshio Path ◽

Numerical Studies ◽

The Kuroshio ◽

Eggs And Larvae ◽

Fish Eggs And Larvae

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Determining seasonal dominant fish eggs and larvae species groups in the west of Tonkin Gulf

Tạp chí Khoa học và Công nghệ Biển ◽

10.15625/1859-3097/16404 ◽

2021 ◽

Vol 21 (2) ◽

pp. 171-181

Author(s):

Huy Pham Quoc ◽

Minh Nguyen Hoang

Keyword(s):

Dominant Species ◽

Species Group ◽

Fish Eggs ◽

Time And Space ◽

The West ◽

Dominant Fish ◽

Gulf Of Tonkin ◽

Species Groups ◽

Eggs And Larvae ◽

Fish Eggs And Larvae

From 2003 to 2016, 1,649 samples were collected, covering both the time and space of the Gulf of Tonkin. The results have identified groups of seasonal dominant fish eggs and larvae: Seven species groups in Spring, nine species groups in the Summer, six species groups in Autumn, and four dominant species groups in the Winter. The dominant index (Yi) ranges from 0.02 to 0.26 depending on the species group and each season of the year, the highest in the Goby group - Gobiidae (Yi = 0.26) achieved in the Spring, followed by Herringgroup - Clupeidae reaches Yi = 0.20 in the Summer and the Anchovy group - Engraulidae reaches Yi = 0.16 in the Summer. The highest advantage index is only Yi = 0.09 in the Winter for Unicorn cod species - Bregmaceros macclelandi. During this period, the number of taxa and dominant indexes tended to decrease from Spring to Winter slightly.

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