17 results on '"Sugumar Vasudevan"'
Search Results
2. Induced thermal stress on serotonin levels in the blue swimmer crab, Portunus pelagicus
- Author
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Saravanan Rajendiran, Beema Mahin Muhammad Iqbal, and Sugumar Vasudevan
- Subjects
Portunus pelagicus ,Serotonin ,Crustacean hypeglycemic hormone ,Pargyline ,Biology (General) ,QH301-705.5 ,Biochemistry ,QD415-436 - Abstract
The temperature of habitat water has a drastic influence on the behavioral, physiological and biochemical mechanisms of crustaceans. Hyperglycemia is a typical response of many aquatic animals to harmful physical and chemical environmental changes. In crustaceans increased circulating crustacean hyperglycemic hormone (CHH) and hyperglycemia are reported to occur following exposure to several environmental stress. The biogenic amine, serotonin has been found to modulate the CHH levels and oxidation of serotonin into its metabolites is catalysed by monoamine oxidase. The blue swimmer crab, Portunus pelagicus is a dominant intertidal species utilized throughout the indo-pacific region and is a particularly important species of Palk bay. It has high nutritional value and delicious taste and hence their requirements of capture and cultivation of this species are constantly increasing. This species experiences varying and increasing temperature levels as it resides in an higher intertidal zone of Thondi coast. The present study examines the effect of thermal stress on the levels of serotonin and crustacean hyperglycemic hormone in the hemolymph of P. pelagicus and analyzes the effect of the monoamine oxidase inhibitor, pargyline on serotonin and CHH level after thermal stress. The results showed increased levels of glucose, CHH and serotonin on exposure to 26 °C in control animals. Pargyline injected crabs showed highly significant increase in the levels of CHH and serotonin on every 2 °C increase or decrease in temperature. A greater CHH level of 268.86±2.87 fmol/ml and a greater serotonin level of 177.69±10.10 ng/ml was observed at 24 °C. This could be due to the effect of in maintaining the level of serotonin in the hemolymph and preventing its oxidation, which in turn induces hyperglycemia by releasing CHH into hemolymph. Thus, the study demonstrates the effect of thermal stress on the hemolymph metabolites studied and the role of pargyline in elevating the levels of serotonin and CHH on thermal stress in the blue swimmer crab, P. pelagicus.
- Published
- 2016
- Full Text
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3. Bioaccumulation level of metals and health risk assessment of selected red and green seaweeds validated by ICP-MS
- Author
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Nigariga Pasumpon, Rahul Varma, and Sugumar Vasudevan
- Subjects
Health, Toxicology and Mutagenesis ,Environmental Chemistry ,General Medicine ,Pollution - Published
- 2023
4. EXTRACTION AND CHARACTERISATION OF CELLULOSE FROM RED SEAWEEDS OF Hypnea musciformis AND Sarconima filliformis
- Author
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Rahul Varma and SUGUMAR VASUDEVAN
- Subjects
Organic Chemistry ,Materials Chemistry - Abstract
The study shows a comparison of cellulose extracted from two species of red seaweeds, namely Hypnea musciformis and Sarconima filliformis. The celluloses were characterized by FTIR, XRD, TGA and SEM analyses. The studies show similarities in the characteristics of the celluloses extracted from H. musciformis and S. filliformis. FTIR analysis confirms the presence of O-H and C-H bonds in the celluloses of both species, while the XRD patterns of celluloses confirm their crystallinity, with a maximum peak at 22°. The thermal stability of the celluloses from H. musciformis and S. filliformis was observed in the range of 250 to 350 °C. The morphological structure of the celluloses was studied using SEM and both celluloses showed smooth pore-free surface.
- Published
- 2022
5. SYNTHESIS AND CHARACTERIZATION OF CELLULOSE AND CELLULOSE NANOCRYSTALS FROM DEAD SEAGRASS – TOWARDS THE WEALTH FROM WASTE CONCEPT'
- Author
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Rahul Varma and SUGUMAR VASUDEVAN
- Subjects
Organic Chemistry ,Materials Chemistry - Abstract
"The study has demonstrated that decaying seagrass accumulated along the shores is a particularly good source of cellulose and cellulose nanocrystals (CNCs). The FTIR spectra indicated the presence of O-H and C-H bonds in both the cellulose and CNCs obtained from the seagrass biomass. The Micro-Raman spectra showed maximum peaks at 1277 cm-1 for cellulose and at 1108 cm-1 for CNCs. The XRD spectra of cellulose confirmed its crystallinity, with a maximum peak for both cellulose and CNCs at 22°. The thermal stability of cellulose was lower than that of CNCs, where the latter showed thermal stability ranging between 110-250 °C. Overall, the cellulose and CNCs obtained showed good crystallinity and thermal stability. The particle size of the CNCs was recorded to be 253.2 nm. Also, they have a large surface area to volume ratio, which contributes to their high strength and stiffness. Thus, the cellulose and CNCs produced from decaying seagrass impart economic value to waste biomass, which can be a step towards the implementation of the wealth from the waste concept."
- Published
- 2022
6. Extraction, Characterization, and Antimicrobial Activity of Chitosan from Horse Mussel Modiolus modiolus
- Author
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Sugumar Vasudevan and Rahul Varma
- Subjects
biology ,General Chemical Engineering ,Extraction (chemistry) ,General Chemistry ,Mussel ,engineering.material ,biology.organism_classification ,Article ,Chitosan ,Chemistry ,chemistry.chemical_compound ,Chitin ,chemistry ,engineering ,Biopolymer ,Fourier transform infrared spectroscopy ,Modiolus modiolus ,Antibacterial activity ,QD1-999 ,Nuclear chemistry - Abstract
Chitin and chitosan have been proved to have enormous applications in biomedical, pharmaceutical, and industrial fields. The horse mussel, Modiolus modiolus, a refuse of the fishery industries at Thondi, is a reserve of rich chitin. The aim of this work is to extract chitosan from the horse mussel and its further characterization using Fourier transform infrared spectroscopy (FTIR), micro-Raman spectroscopy, X-ray diffraction (XRD), and elemental analysis. The result of FTIR studies revealed different functional groups of organic compounds such as out-of-plane bending (564 cm–1), C–O–C stretching (711 cm–1), and CH2 stretching (1174 cm–1) in chitosan. The degree of acetylation of the extracted chitosan was observed to be 57.43%, which makes it suitable as a biopolymer for biomedical applications. Prominent peaks observed with micro-Raman studies were at 484 cm–1 (14,264 counts/s), 2138 cm–1 (45,061 counts/s), and 2447 cm–1 (45,636 counts/s). XRD studies showed the crystalline nature of the polymer, and the maximum peak was observed at 20.04°. Elemental analysis showed a considerable decrease in the percentage of nitrogen and carbon upon the conversion of chitin to chitosan, while chitosan had a higher percentage of hydrogen and sulfur. The antibacterial activities of chitosan from the horse mussel were found to be efficient at a 200 μg/mL concentration against all the bacterial strains tested with a comparatively higher antibacterial activity against Escherichia coli (9 mm) and Bacillus subtilis (8 mm).
- Published
- 2020
7. Impact of Mg2+ and Zn2+ Addition on the Structural, Morphological, Physicochemical, Dielectric and Biological Properties of Hydroxyapatite
- Author
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Amali Roselin Arockiam, Poonguzhali Ramaswamy, Panneerselvam Ramaswamy, Sugumar Vasudevan, Anandhan Narayanasamy, Joseph Panneerdoss Issac, and Ganesan Karuppannan Periannan
- Subjects
Materials science ,Chemical engineering ,Biological property ,Dielectric - Abstract
In the present work, the wet-chemical precipitation technique is employed to prepare Zinc/Magnesium doped hydroxyapatite (HAP). In doped HAP, the X-ray diffraction peak shifts to a higher angle because of the contraction of the lattice parameters along a - axis. The Raman peaks at 519, 440, 1464 cm-1 indicate the presence of Mg, Zn and CO32- in doped HAP respectively. The Field Emission Scanning Electron Microscopy (FESEM) measures the grain size of pure, 5% Zn and 5% Mg doped HAP, as 275, 510, and 251 nm respectively. Transmission Electron Microscopy (TEM) confirmed the morphological change in HAP. The X-ray photoelectron spectroscopy (XPS) identifies the presence of Mg2+ and Zn2+ in doped HAP. The dopant elevates the hardness and dielectric constant, so the strength and the bone growth of HAP increases. All the doped samples show excellent antibacterial, antifungal and antibiofilm activities than the pure HAP.
- Published
- 2021
8. Geochemical and elemental characterization of rostrum and alveolus parts of Belemnite fossil from the Late Cretaceous formation, Tamil Nadu, India
- Author
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Neetu Mohan, Sugumar Vasudevan, Paramasivam Chellamuthu Ranganathan, and Anandhan Narayanasamy
- Subjects
Calcite ,biology ,Rostrum ,Geochemistry ,engineering.material ,biology.organism_classification ,Feldspar ,Cretaceous ,Orthoclase ,chemistry.chemical_compound ,chemistry ,visual_art ,engineering ,visual_art.visual_art_medium ,General Earth and Planetary Sciences ,Kaolinite ,Sedimentary rock ,Belemnites ,Geology ,General Environmental Science - Abstract
About 135 million years before, a form of marine animal called belemnites existed during the geological period of the Jurassic and Cretaceous. The Cauvery Basin is a pericratonic basin that lies along the southeast coast of India. The belemnites fossil used in the present study is collected from Karai East, Ariyalur District, Tamil Nadu. The inner and outer parts of the cross-section differ in the size of calcite forms and building up in the fossil. Geochemical characterization of rostrum and alveolus in the fossil was done to determine the mineral constitutions and assemblages. The elements were characterized by Fourier Transform Infrared (FTIR), Micro Raman, X-ray Powder Diffractometry (XRD) and X-ray fluorescence (XRF) analyses. A strong calcite mineral deposition was observed in the central part of the rostrum together with kaolinite and orthoclase feldspar as minor components. The peak observed in 3421, 2926 and 3436, 2924 cm-1 are the characteristic peaks of kaolinite in the rostrum and the alveolus respectively. The peaks were observed at 1038 cm-1 are the characteristic peak of orthoclase feldspar. The advent methodology directly and non-invasively affords spatially resolved assessments of organic matter preservation and microscale chemical diversity within any geologically preserved terrestrial sedimentary sample in technological applications.
- Published
- 2021
9. Thermal stress induced hyperglycemia in the blue swimmer crab, Portunus pelagicus
- Author
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Saravanan Rajendran and Sugumar Vasudevan
- Subjects
medicine.medical_specialty ,Thermal shock ,animal structures ,Invertebrate Hormones ,Physiology ,Brachyura ,Hepatopancreas ,Nerve Tissue Proteins ,Biochemistry ,Arthropod Proteins ,chemistry.chemical_compound ,Recovery period ,Internal medicine ,Hemolymph ,medicine ,Animals ,Glycogen ,biology ,fungi ,Hyperglycemic hormone ,Portunus pelagicus ,biology.organism_classification ,Crustacean ,Up-Regulation ,Endocrinology ,Glucose ,chemistry ,General Agricultural and Biological Sciences ,Heat-Shock Response ,Developmental Biology - Abstract
Hyperglycemia is a stress responsible mechanism induced in crustaceans through the secretion of Crustacean Hyperglycemic Hormone (CHH). The effect of thermal shock on the hemolymph CHH levels was studied in P. pelagicus. Crabs were exposed to varying temperatures for 3 h and were then transferred to ambient temperature (28 °C). A higher CHH level of 47.30 ± 2.26 fmol/ml was observed on exposure of crabs to 24 °C, over a recovery period of 3 h. This was reflected with increase in hemolymph glucose causing hyperglycemia and subsequent decrease in hepatopancreas glycogen levels. The results suggest the modulatory role of CHH in producing the energy required for the physiological reparation faced by the crabs during thermal stress.
- Published
- 2021
10. Baseline study of trace metal concentrations in abandoned, lost or otherwise discarded fishing gear along Thondi coast, Palk Bay, India
- Author
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Nigariga Pasumpon and Sugumar Vasudevan
- Subjects
Aquatic Science ,Oceanography ,Ecology, Evolution, Behavior and Systematics - Published
- 2022
11. Seasonal variation of heavy metals in seagrasses along Thondi coast, Palk Bay, India
- Author
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Sugumar Vasudevan and Nigariga Pasumpon
- Subjects
Health, Toxicology and Mutagenesis ,Halophila ovalis ,chemistry.chemical_element ,India ,010501 environmental sciences ,Monsoon ,01 natural sciences ,Metals, Heavy ,medicine ,Environmental Chemistry ,Ecotoxicology ,0105 earth and related environmental sciences ,Cadmium ,Alismatales ,biology ,General Medicine ,Seasonality ,medicine.disease ,biology.organism_classification ,Pollution ,Seagrass ,chemistry ,Bays ,Bioaccumulation ,Environmental chemistry ,Environmental science ,Seasons ,Bay ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
The present study deals with the bioaccumulation of heavy metals in different seagrass species (Syringodium isoetifolium, Halodule pinifolia, Cymodocea serrulata, Halophila ovalis) along Thondi coast and decaying seagrass offshore. Heavy metal concentrations in the seagrass samples were analysed during the period of April 2019 to March 2020 using atomic absorption spectrophotometry. Among the heavy metals assayed, the level of manganese was higher (15.62 ± 1.02 mg/kg) and chromium was the least metal observed (0.002 mg/kg). One-way ANOVA revealed significantly higher level of heavy metals in summer season, while it gradually decreased through pre-monsoon to monsoon season (P < 0.05). Cadmium and chromium were observed to be below detectable levels in the seagrass species. S. isoetifolium was found to bioaccumulate higher levels of heavy metals than the other seagrass species studied. Elucidation of heavy metal levels in the dead and decayed seagrass offshore revealed a higher level of heavy metals than live seagrass species.
- Published
- 2020
12. Activation of prophenoloxidase and hyperglycemia as indicators of microbial stress in the blue swimmer crab Portunus pelagicus
- Author
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Sugumar Vasudevan and Saravanan Rajendran
- Subjects
0106 biological sciences ,Brachyura ,Microorganism ,010501 environmental sciences ,Aquatic Science ,Oceanography ,medicine.disease_cause ,01 natural sciences ,Microbiology ,Hemolymph ,medicine ,Escherichia coli ,Animals ,Incubation ,0105 earth and related environmental sciences ,Vibrio ,chemistry.chemical_classification ,Enzyme Precursors ,biology ,Chemistry ,Vibrio harveyi ,010604 marine biology & hydrobiology ,Portunus pelagicus ,Prophenoloxidase ,biology.organism_classification ,Pollution ,Enzyme ,Hyperglycemia ,Catechol Oxidase - Abstract
Portunus pelagicus is exposed to different kinds of microorganisms leading to high metabolic stress that affects its life. The present study evaluates the activity of Phenoloxidase (PO), which is an enzyme that is actively involved in the activation of the immune defense system and hyperglycemia in P. pelagicus challenged with Escherichia coli and Vibrio harveyi injections. The results revealed a major impact of microbial injection on PO activity and significant variations in hemolymph glucose and CHH levels. Reduction of glucose level was observed after 24 h microbial incubation (275.26 ± 28.85 and 175.23 ± 21.70 μg/ml in V. harveyi and E. coli injected crabs, respectively). An elevated level of CHH (13.54 ± 0.55 fmol/ml) was observed in V. harveyi-injected crabs, and increased PO activity was recorded in E. coli-injected crabs. The results of the present study indicate that microbial stress leads to the activation of the defense system and hyperglycemia in P. pelagicus.
- Published
- 2020
13. Isolation, identification and characterization of the bioluminescent bacteria isolated from the blue swimmer crab Portunus pelagicus along Thondi Coast and virulence studies at high temperatures
- Author
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Beema Mahin Muhammad Iqbal, Sugumar Vasudevan, and Saravanan Rajendran
- Subjects
DNA, Bacterial ,0301 basic medicine ,Hot Temperature ,Brachyura ,030106 microbiology ,India ,Zoology ,Virulence ,Microbiology ,Foodborne Diseases ,Fish Diseases ,03 medical and health sciences ,Species Specificity ,RNA, Ribosomal, 16S ,Animals ,Humans ,Sea food ,Phylogeny ,Vibrio ,Base Sequence ,biology ,Vibrio harveyi ,Portunus pelagicus ,Sequence Analysis, DNA ,Bioluminescent bacteria ,biology.organism_classification ,Isolation (microbiology) ,030104 developmental biology ,Infectious Diseases ,Seafood ,Vibrio Infections ,Food Microbiology ,16s rrna gene sequencing ,Extended time ,Water Microbiology - Abstract
The current study was conducted to isolate the marine bioluminescent bacteria from the blue swimmer crab Portunus pelagicus along the Thondi Coast. Morphological, biochemical and molecular characterization techniques including 16S rRNA gene sequencing and phylogenetic analyses confirmed that the isolated strain was Vibrio harveyi. Experiments were further carried out at different temperatures and various time intervals and the results revealed a significant effects of high temperature and extended time duration on elimination of V. harveyi. Hence, high temperature treatments could facilitate the suppression of V. harveyi from sea food and thereby, preventing food borne infections during human consumption.
- Published
- 2018
14. Localization and identification of crustacean hyperglycemic hormone producing neurosecretory cells in the eyestalk of blue swimmer crab,Portunus pelagicus
- Author
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Saravanan Rajendiran and Sugumar Vasudevan
- Subjects
Cell type ,Histology ,Hyperglycemic hormone ,Portunus pelagicus ,030206 dentistry ,02 engineering and technology ,Anatomy ,Biology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Crustacean ,Eyestalk ,03 medical and health sciences ,Medical Laboratory Technology ,0302 clinical medicine ,Immunohistochemistry ,0210 nano-technology ,Instrumentation ,Fixative ,Medulla - Abstract
This study intensely focuses on to the localization and identification of crustacean hyperglycemic hormone (CHH) producing neurosecretory cells in the eyestalk of the blue swimmer crab Portunus pelagicus. Anti-Carcinus maenas-CHH was used to identify the location of CHH neurosecretory cells by immunohistochemistry. Ten pairs of eyestalks were collected from intact adult intermoult female crab and fixed in Bouin's fixative. Eyestalks were serially sectioned and stained with chrome-hematoxylin-phloxine stain. Histological studies show the presence of different types of neurosecretory cells namely A (multipolar), B (tripolar), C (bipolar), D (unipolar), E (oval), and F (spherical) in the medulla interna, externa, and terminalis regions based on their size, shape, and tinctorial properties. The neurohemal organ, sinus gland (SG) was observed laterally between medulla interna and terminalis regions. Immunohistochemical studies showed the presence of distinct CHH-like immunoreactivity in the optic ganglia. Divergent group of neurosecretory cells with varying degree of immunoreactivity with Anti-Carcinus maenas-CHH (low, moderate, and intense reactivity) were identified in medulla terminalis, medulla interna, medulla externa, and sinus gland. The present study maps the various types of neurosecretory cells in the optic ganglia and also shows the presence of CHH-like immunoreactivity in various regions of optic ganglia in P. pelagicus. The presence of these unique neurosecretory cell types with larger cell diameter in medulla terminalis, a region that bears the neurosecretory cell bodies, suggest high secretory activity.
- Published
- 2016
15. Serotonin modulation of hemolymph glucose and crustacean hyperglycemic hormone titers in Fenneropenaeus indicus
- Author
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Munuswamy Natesan, Santhoshi Sathyanandam, and Sugumar Vasudevan
- Subjects
medicine.medical_specialty ,animal structures ,fungi ,Aquatic Science ,Biology ,Carbohydrate metabolism ,biology.organism_classification ,Crustacean ,Shrimp ,Eyestalk ,Titer ,Endocrinology ,Internal medicine ,Darkness ,Hemolymph ,medicine ,Serotonin - Abstract
Crustacean hyperglycemic hormone (CHH), a neurohormone synthesized and released from the X-organ sinus gland complex, is primarily involved in carbohydrate metabolism. Biogenic amines and peptidergic neuroregulators are known to modulate the release of CHH. Although mechanisms involved in hormone release in the shrimp, Fenneropenaeus indicus is poorly understood. Daily variations in the levels of crustacean hyperglycemic hormone and serotonin in the shrimp F. indicus were studied. Both CHH and glucose levels increase during the first hours after the beginning of darkness. The animals were injected with serotonin and glycemic and CHH levels were determined after 2 h of injection. Serotonin caused significant hyperglycemia (P
- Published
- 2008
16. Physical, biochemical and functional characterization of haemoglobin from three strains of Artemia
- Author
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Sugumar Vasudevan and Natesan Munuswamy
- Subjects
Protein Denaturation ,Physiology ,Size-exclusion chromatography ,Bohr effect ,Brine shrimp ,Biochemistry ,Sepharose ,Hemoglobins ,Species Specificity ,Animals ,Denaturation (biochemistry) ,Protein Structure, Quaternary ,Molecular Biology ,Polyacrylamide gel electrophoresis ,Gel electrophoresis ,Chromatography ,Molecular mass ,biology ,Temperature ,Hydrogen-Ion Concentration ,biology.organism_classification ,Molecular Weight ,Oxygen ,Electrophoresis, Polyacrylamide Gel ,Artemia - Abstract
The brine shrimp, Artemia, an inhabitant of coastal and inland salterns, encounter fluctuations in the salinity which in turn influences the oxygen availability of their habitat. Hence, experiments were performed to analyze variations in haemoglobin structure and patterns of three strains of Artemia from South India and also to reflect the effect of varying oxygen levels in their habitat. Haemoglobins were purified on a DEAE-Sephadex column and haemoglobin types were analyzed by comparing their relative mobility on a non-denaturing medium. Furthermore, their molecular masses were determined by gel filtration in Sepharose column and by dodecylsulfate polyacrylamide gel electrophoresis. Results clearly reveal the presence of three distinct extracellular haemoglobins Hb I, Hb II and Hb III in Tuticorin strain while the other strains displayed only trails or the complete absence of Hb III and Hb II. Estimated molecular masses of these haemoglobins are 235,000-250,000 Da. Denaturation of the reduced and alkylated haemoglobins revealed apparently one polypeptide chain with a molecular mass of 124,000 Da. Upon denaturing gel electrophoresis of native haemoglobin Hb II, it was found that the 124,000 Da, polypeptide was cleaved specifically into two unequally-sized fragments of 50,400 and 79,800 Da. With regard to oxygen affinity, Hb III has a very high affinity for oxygen, an almost negligible Bohr effect and a good physiological adaptation to temperature changes. By combining the three haemoglobins in different proportions Artemia strains must be able to withstand diverging environmental conditions. In particular, the absence of Hb III in Puthalam and its occurrence as a faint band in Thamaraikulam could be correlated to the oxygen levels of their habitats.
- Published
- 2007
17. Reproduction in the brine shrimp Artemia Leach, 1819 (Branchiopoda, Anostraca) from South India: Laboratory cross fertility tests and mating behaviour.
- Author
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Sugumar, Vasudevan
- Subjects
FERTILITY ,ANIMAL offspring sex ratio ,ARTEMIA ,OVIPARITY - Abstract
The brine shrimp Artemia is an inhabitant of hypersaline environments and has been used to study primary reproductive traits and mating behaviour together with the degrees of divergence among populations. Intrapopulation experimental crosses and cross-fertility tests were evaluated in four populations from coastal and inland environments of South India, and in a reference sample of A. franciscana (San Francisco Bay -SFB, U.S.A). Crosses were fertile with the production of live nauplii and cysts. Significant variations were observed among the populations studied in fecundity (e.g. total offspring, brood size). A reproductive switch from ovoviviparity to oviparity was observed, especially in crosses between inland populations with the reference strain. Differences between the South Indian samples and SFB were significant- for the total number of nauplii, percentage of encysted brood and broods per female. A peculiar pattern of male-male mating was observed, wherein the ratio of males was higher than females. About 70% of the orientation movements of the males were directed towards other males. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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