Definition of a new unbiased gonad index for aquatic invertebrates and fish: its application to the sea urchin Paracentrotus lividus

Despite the extensive use of sea urchins in embryology, the hormonal mechanisms regulating echinoid reproductive processes are scarcely known. This research is focused on the role of estradiol (E2), whose presence and seasonal variations in different echinoderm tissues have been previously reported. Three different concentrations of E2 were administered (via peristomial injection, 2/week) to adult specimens of the sea urchin Paracentrotus lividus for 2 and 12 weeks. The lowest concentration was close to physiological values, previously measured in field specimens. Despite the increase of circulating E2 in the coelomic fluids, neither short- nor long-term hormonal treatment induced marked variations in the considered reproductive parameters. The Gonad Index appeared to be more influenced by the feed intake than by E2. Similarly, the maturation stage of the gonads was not markedly affected by E2 injection, although some sex-specific differences could be observed: treated females never reached the maximum maturation stage compared to controls, although this was observed in males injected with the lowest E2 concentration. Although further research is needed to confirm our observations, according to the present study E2 does not markedly influence echinoid reproduction and, particularly, it does not promote female maturation, as reported for vertebrates and suggested for asteroid echinoderms.

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Reproductive cycle of the sea urchin Paracentrotus lividus in the Cantabrian Sea (northern Spain): environmental effects

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540999110x ◽

2009 ◽

Vol 90 (4) ◽

pp. 699-709 ◽

Cited By ~ 30

Author(s):

J.M. González-Irusta ◽

F. Goñi de Cerio ◽

J.C. Canteras

Keyword(s):

Sea Urchin ◽

Reproductive Cycle ◽

Phytoplankton Bloom ◽

Chlorophyll Concentration ◽

Gonad Index ◽

Paracentrotus Lividus ◽

Northern Spain ◽

Spring Phytoplankton Bloom ◽

In The Beginning ◽

Spawning Periods

The main objective of this study was to describe the reproductive cycle of the sea urchin Paracentrotus lividus on the Cantabrian coast (north of Spain), and assess its relationship with environmental factors. To achieve this, samples were taken monthly from three localities during 17 months in two different habitats. At least 15 individuals from each location and habitat were collected during each sampling occasion and used for assessments of gonad index and histological sections. The water temperature and the chlorophyll concentration were also measured. The breeding season of P. lividus in Cantabria started in March and continued until September with one or two main spawning periods per year (depending on year and population), the first one in the beginning of spring and the second one in the summer. The most important differences in the gonad cycle were observed among localities, and the smallest among habitats. Temperature, photoperiod and nutritive stage are important factors controlling the gonad cycle. The beginning of spawning in the Cantabrian populations coincides with the spring phytoplankton bloom and the rise in temperature, which may act as environmental triggers.

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The Influence of Season on the Gonad Index and Biochemical Composition of the Sea UrchinParacentrotus lividusfrom the Golf of Tunis

The Scientific World JOURNAL ◽

10.1100/2012/815935 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 31

Author(s):

Soumaya Arafa ◽

Moncef Chouaibi ◽

Saloua Sadok ◽

Amor El Abed

Keyword(s):

Seasonal Variation ◽

Sea Urchin ◽

Biochemical Composition ◽

Gonad Index ◽

Paracentrotus Lividus ◽

Spawning Period ◽

Total Fatty Acids ◽

Pufa Group ◽

Main Component ◽

High Level

Seasonal variation in the gonad weight and biochemical composition of the sea urchinParacentrotus lividusfrom the Golf of Tunis (Tunisia) were studied between September 2003 and August 2004. The highest gonad indices occurred in March (16.71%). The spawning period occurred between April and July and resulted in a fall in gonad indices to low level (7.12 ± 0.12%). Protein constituted the main component of the gonad, and lipid and carbohydrate were found at appreciable amounts. Consistent with the gonad cycle, sea urchin biochemical components showed clear seasonal variation with a significant decrease during the spawning period. The polyunsaturated fatty acid (PUFA) group was found at high level (40% of the total fatty acids). Of the PUFA group, eicosapentaenoic (C20:5n−3) and eicosatetraenoic (C20:4n−3) were the most abundant gonadal lipids. The level of PUFA was significantly affected by temperature variation showing an increase during the cold months and a decrease in the hot months.

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Effects of Ethinylestradiol (EE2) and an Organophosphorus Flame Retardant (TCPP) on Gonadal Maturation in the Sea Urchin, Paracentrotus lividus

Journal of Marine Science and Engineering ◽

10.3390/jmse8080611 ◽

2020 ◽

Vol 8 (8) ◽

pp. 611

Author(s):

Pedro Campoy-López ◽

Estefanía Pereira-Pinto ◽

Leonardo Mantilla-Aldana ◽

Ricardo Beiras

Keyword(s):

Flame Retardant ◽

Sea Urchin ◽

Sea Urchins ◽

Gonad Development ◽

Gonad Index ◽

Paracentrotus Lividus ◽

Individual Variability ◽

Estrogenic Effects ◽

Histological Damage ◽

Initial Stage

The sea urchin (Paracentrotus lividus) was used to test the effects of one of the most abundant flame retardant additives for plastics, tris (1-chloro-2-propyl) phosphate (TCPP), and the synthetic hormone ethinylestradiol (EE2) on gametogenesis and gonad development of adults. With this aim, 403 individuals of both sexes were exposed to TCPP concentrations ranging from 0.2 to 10 µg/L, EE2 (0.01 µg/L), seawater and solvent controls for 7 and 28 days. EE2 and TCPP exposure did not cause histological damage in the gonads. Some evidence of estrogenic effects of TCPP within the µg/L range and EE2 within the ng/L range is reported. Females exposed to 1 µg/L TCPP for 7 days showed a significant increase in gonad development assessed as gametogenic stage, females exposed to 10 µg/L TCPP showed increased gonad development both in terms of weight (Gonad Index, GI, at both 7 and 28 days) and maturation (Pixelar Index, PI), and females exposed to 10 ng/L EE2 showed increased PI after 28 days exposure. Male sea urchins exposed to both TCPP and EE2 for 7 days showed increased frequencies of low development gonad stage. However, the patterns of response are affected by the high inter-individual variability, the differing initial stage of the gonad, as well as the dosage administered.

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Seasonal changes in the biochemical composition of body components of the sea urchin, Paracentrotus lividus, in Lorbé (Galicia, north-western Spain)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315403007501h ◽

2003 ◽

Vol 83 (3) ◽

pp. 575-581 ◽

Cited By ~ 33

Author(s):

M.F. Montero-Torreiro ◽

P. Garcia-Martinez

Keyword(s):

Seasonal Variation ◽

Sea Urchin ◽

Biochemical Composition ◽

Gonad Index ◽

Paracentrotus Lividus ◽

Dry Weight ◽

Spawning Period ◽

Biochemical Components ◽

Western Spain ◽

North Western

Seasonal variations in the gonad index and the biochemical composition of gonad and gut tissue of the sea urchin, Paracentrotus lividus (Echinodermata: Echinoidea) were determined. Samples were collected from Lorbé (Galicia, north-western Spain) between November 1994 and October 1995. The gametogenic cycle of the sea urchin was annual, with a long, single spawning period from May to August 1995. Most of the biochemical components in gonad showed clear seasonal variation, which was related to the gonad cycle. The main component was protein, which ranged between 36 and 60% of the dry weight, with maximum levels coinciding with the minimum levels of glycogen. Gonad glycogen therefore seemed to be the energy source employed for protein synthesis during gametogenesis. Seasonal variation in total lipids in the gonad was less evident; the main lipidic component was triacylglycerol (around 10% of the dry weight), whereas total cholesterol accounted for less than 1%. The gut does not seem to act as a storage tissue in P. lividus and seasonal variation in biochemical components may be a consequence of fluctuations in the availability of food.

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Effects of Glyphosate-Based and Derived Products on Sea Urchin Larval Development

Journal of Marine Science and Engineering ◽

10.3390/jmse8090661 ◽

2020 ◽

Vol 8 (9) ◽

pp. 661

Author(s):

Davide Asnicar ◽

Costanza Cappelli ◽

Ahmad Safuan Sallehuddin ◽

Nur Atiqah Maznan ◽

Maria Gabriella Marin

Keyword(s):

Larval Development ◽

Sea Urchin ◽

Marine Invertebrates ◽

Parent Compound ◽

Paracentrotus Lividus ◽

Marine Species ◽

Negative Effects ◽

Aminomethylphosphonic Acid ◽

Main Degradation Product ◽

Herbicide Glyphosate

Despite the widespread use of herbicide glyphosate in cultivation, its extensive runoff into rivers and to coastal areas, and the persistence of this chemical and its main degradation product (aminomethylphosphonic acid, AMPA) in the environment, there is still little information on the potential negative effects of glyphosate, its commercial formulation Roundup® and AMPA on marine species. This study was conducted with the aim of providing a comparative evaluation of the effects of glyphosate-based and its derived chemicals on the larval development of the sea urchin Paracentrotus lividus, thus providing new data to describe the potential ecotoxicity of these contaminants. In particular, the effects on larval development, growth and metabolism were assessed during 48 h of exposure from the time of egg fertilization. The results confirm that AMPA and its parent compound, glyphosate have similar toxicity, as observed in other marine invertebrates. However, interestingly, the Roundup® formulation seemed to be less toxic than the glyphosate alone.

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Biometric characteristics of the wild population of sea urchin Paracentrotus lividus (Lamarck, 1816) on the Tunisian coast

Thalassas An International Journal of Marine Sciences ◽

10.1007/s41208-021-00301-8 ◽

2021 ◽

Author(s):

F. Sellem ◽

B. Bouhaouala-Zahar

Keyword(s):

Sea Urchin ◽

Wild Population ◽

Multivariable Analysis ◽

Paracentrotus Lividus ◽

Biometric Data ◽

Relative Growth ◽

Tunisian Coast ◽

Population Discrimination ◽

Positive Growth ◽

Negative Growth

AbstractThe present study was conducted to provide biometric data of the edible sea urchin Paracentrotus lividus along the Tunisian coastline where thirteen marine localities were selected randomly. A total of 653 individuals were collected and their metric and weight measurements were recorded. The size distribution of the different samples was determined and relative growth expressions were deduced. Data analysis showed that all localities’ samples of the wild population were dominated by one-size class, except Port Prince and Haouaria. Interestingly, only diameter-height relationships (D-H) were different between the geographical localities. Diameter-weight relationships (D-TW and D-TWTE) revealed a significant negative growth for all the localities, with the exception of Gammarth which showed positive growth for total weight (D-TW). Moreover, the multivariable analysis revealed divergences and/or similarities between metric and weight variables. Altogether, data highlights the inter-population discrimination with respect to geographic localization and clear segregation between the northern and the eastern localities demonstrated the plasticity of the species.

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