Ossicle Morphology of Sandfish (Holothuria scabra) Across Maturity Stages | InformativeBD

Jason N. Tersol, Maribel V. Gabuyo, Lymuel May M. Palmones, Fraxie D. Manipon, and John Raymund D. Torres, from the different institute of Philippines. wrote a Research Article about, Ossicle Morphology of Sandfish (Holothuria scabra) Across Maturity Stages. Entitled, Ossicle morphology of Sandfish (Holothuria scabra Jaeger) at different stages of maturity. This research paper published by the International Journal of Biosciences (IJB). an open access scholarly research journal on Biosciences. under the affiliation of the International Network For Natural Sciences| INNSpub. an open access multidisciplinary research journal publisher.

Abstract

Holothuria scabra Jaeger was investigated for its ossicle morphology by the use of spicule analysis. Buttons, tables, and rods are the most observable ossicles in all weight ranges. Different kinds of rod ossicles such as I-shape rods, spiny branched rods, and less spiny branched rods were observed in some weights. Weights ranged in 20-59g, 60-89g, and 90g and above respectively. I-shape rods was observed in the ventral region of specimens weighing 65g, and 93g, while it was also observed in the dorsal region of specimen weighing 252g. Both spiny and less spiny branched rods were observed mostly on the specimens weighing 40g, and 50g. Other ossicles observed were branched rods, ring-like ossicle, and ellipsoid in buttons. Results obtained in this study show that buttons are the most abundant ossicle observed in the adult stage of H. scabra Jaeger. It is advised that future research use samples weighing between 20 and 250 grams to examine the ossicle formations present on these weights, measure the sizes of the ossicles to be observed with the suggested weights of sample species, and conduct additional sampling from other sites to determine whether a particular ossicle morphology first appears at a particular stage of maturity and may be absent in succeeding stages of maturity.

Read more : Hormonal Shifts in Fatherhood: The Oxytocin-Testosterone Connection | InformativeBD

Introduction

Sea cucumbers are benthic marine invertebrates that belong to the taxonomic class Holothuroidea that fall under the Phylum Echinodermata (Al- Yagout et al., 2021). They are related to other well-known echinoderms such as sea stars, sea urchins, and sand dollars (Ross, 2019). These marine invertebrates are elongated or cylindrical in shape, resembling a large cucumber plant that contains a single branched gonad, and has leathery and spiny skin (Pangestuti & Arifin, 2017; Ross, 2019; Susetya et al., 2020). Benthic organisms like sea cucumbers have an importance on the ecosystem. Ecologically, they recycle benthic organic matter through the consumption of sediments, sea grasses, organic detritus, and produce fecal (Dar & Ahmad, 2006; Wolkenhauer et al., 2010). Some sea cucumbers, like those which belong to the genera Holothuria, Actinopyga, and Bohadschia, are edible and commonly a source of food (Torres et al., 2019). The body walls, gonads and intestines of these marine creatures are consumed because of their nutritional values (Purcell et al., 2012). Some studies have also shown multiple biological properties of sea cucumbers (Althunibat et al., 2009; Bordbar et al., 2011; Mamelona & Pelletier, 2010; Torres et al., 2021). Aside from being a source of food, these marine organisms have also been used as a medicinal ingredient since ancient times (Mohsen & Yang, 2021). Since the sea cucumbers are utilized as food and medicine, overexploitation 2 of the species might lead to them being endangered and in worst cases, might become extinct.

Sea cucumbers or Holothurians are diverse and consist of six orders and nearly 1,400 species (Dabbagh & Sedaghat, 2012). In the Philippines, the species of sea cucumbers are highly diverse, which is threatened by overfishing and habitat loss (Pitogo et al., 2018). There are 170 species identified in the country wherein 25 to 41 species of these are mostly from the members of the families Holothuroidea and Stichopodidea and they are commercially valued wherein they are commonly exploited for trade (Gamboa et al., 2004; Jontila et al., 2014; Olavides et al., 2010). Meanwhile, sea cucumbers are also traded for aquarium purposes (Bordbar et al., 2011). In China, there are about 20 species of edible sea cucumbers that have been considered as traditional medicine and tonic food for many years. Nutrient analysis shows that the body wall and intestines of sea cucumbers have a high nutrient value (Conand, 2004). Most of the commercially important sea cucumbers have been fished with increasing intensity (Wolkenhauer et al., 2010). They are vulnerable to harvesting because of their high abundance and easy access to their habitats (Purcell et al., 2012).

Sea cucumbers have unique names from different places. “Beche-de-mer” is a French word that means marine food product. Locally, sea cucumbers are known as “balat” or “balatan”. It is also known as “balat kagisan” or “putian” (Perez, 2011). Dried sea cucumbers are known as “trepang” in Indonesia.

One of the species of sea cucumbers is the Holothuria scabra Jaeger. It is considered one of the most commercially valuable species for beche-de-mer production and has been widely fished in the tropics. Beche-de-mer is processed from sea cucumbers 3 belonging to the families Holothuroidea and Stichopodidea. These species are distributed worldwide as found in the Indo- West Pacific region including the Islands of the Western Indian Ocean, Mascarene Islands, East Africa, and Madagascar, Red Sea, Southeast Arabia, the Persian Gulf, West coast of India and Pakistan, Maldives, and the Lakshadweep, Sri Lanka, Bay of Bengal, the East Indies, North Australia, the Philippines, China, Southern Japan, South Pacific Islands and the Hawaiian Islands (Dabbagh et al., 2012). The A-grade classification of beche-de-mer from sandfish (Holothuria scabra Jaeger) commands one of the highest prices on the international market (Agudo, 2006). Due to global overexploitation by intensive commercial extraction, they are listed as endangered by the International Union for the Conservation of Nature. Most heavily exploited sea cucumber populations suffer rapid declines in their abundance and population densities with the onset of commercial exploitation. The declining numbers of sea cucumbers have serious consequences in the ecosystem such as habitat structure alteration, as they are the seas’ bioturbators and recyclers (Wolkenhauer et al., 2010).

Holothuria scabra Jaeger is commonly known as sandfish because of its ability to thrive in calm sandy or muddy coastal areas. They are characterized to tolerate low saline environments and are sometimes found to proliferate in some estuarine environments (Junus et al., 2018). Sandfish (Holothuria scabra) move with the help of tube feet densely distributed on the ventral surface of the body wall and also through muscular action of the body wall (Hame et al., 2001). Echinoderms may be able to thrive as a result of this to interact with the surroundings from every angle (Yoshimura et al., 2012). 

Sandfish (Holothuria scabra Jaeger) undergo a metamorphic phase that transforms from larva to adult and undergoes a complex development and regeneration of internal 4 organs. The newly emerged juveniles sink to the bottom in order to complete their development and take on the adult form but will continue to grow until they reach the full adult size (Al-Rashdi et al., 2012). The morphological features used to identify holothurian species are the ossicles. Sea cucumbers have ossicles that form part of their skeleton. The ossicles are small parts of iron-rich calcified materials that are made of calcium carbonate which are infused with the tissue and covered by the epidermis. It varies on shape and size which creates a diversity of species. Some studies stated that describing the morphology of ossicle formation or shapes is useful for species identification and is necessary for establishing extensive data for characterizing the sea cucumber species (Kamarudin et al., 2017; Torres et al., 2019). Their shapes, in fact, have continued to be an important characteristic for the morphological identification of sea cucumbers (Torres et al., 2019). According to Sticker (1986), among the shapes of ossicles include perforated rods, buttons, and tables. The formation of the ossicles occurs on the multinucleated syncytia of sclerocytes on the dermal layer of the body wall (Sticker, 1986). The ossicles of sea cucumbers occur scattered throughout the dermal layer of the body wall. Presumably, it helps to increase the overall stiffness of the body wall. Ossicles could lead to such a stiffening by acting analogously to the various types of biological “filler particles” that have been studied in other invertebrates. Aside from probably increasing the overall stiffness of the body wall, these ossicles may form discrete coverings that help to protect internal structures from mechanical damage. Furthermore, ossicles may also function as antipredatory devices by making juvenile and adult sea cucumbers less palatable (Sticker, 1986).

According to the United Nations' Food and Agriculture Organization (FAO), Asia is the world’s leading supplier of sea cucumber, accounting for roughly 93 percent of global production. Southeast Asia represents the global market “hotspots” for sea cucumber trade due to their known “mega biodiversity”. Many sea cucumbers are gathered for human consumption and some are cultivated in aquaculture systems (Pangestuti & Arifin, 2017). The number of commercially exploited species varies widely, with the highest number of species in Asia (52 species) and Pacific (36 species) regions, partially due to the higher natural diversity in these areas. The majority of sea cucumbers are exported for the bechede-mer market, with a few species for the live trade (aquarium) market (Han et al., 2016). The Philippines was already recognized as one of the largest exporters of commercially important sea cucumber species for many years (Torres, 2015). However, in spite of its growing local and international trade and the spread of some information for their utilization, there is still a dearth of knowledge on their systematics and macro biota (Macfadyen et al., 2009). Information about most holothuroid species’ biology and ecology is still limited in our country (Torres, 2015; Torres et al., 2019). References on sea cucumber species are only confined to local descriptions in the Philippines, according to reports. It is also difficult to compare studies because different regional names are utilized (Torres et al., 2019). According to a report by the Bureau of Fisheries and Aquatic Resources (BFAR), sea cucumber species are vulnerable to exploitation and extinction due to a lack of information, which is usually manifested by a decrease in the number of catches, particularly for commercially important species found near the described mainland fishing areas (Brown et al., 2010).

Age is important for animal biology and is fundamental for estimating baseline parameters such as growth rate, population age structure productivity, mortality rate, and recruitment (Sun et al., 2019). The body weight and size of the sea cucumber (Holothuria scabra Jaeger) sub-adult stage can be distinguished. Sexually mature sea cucumbers, on the other hand, are difficult to identify only by their weight and size, however, most developed sea cucumbers weigh around 250 grams. The size when they reach sexual maturity varies by region (Hamel et al., 2001; Purcell et al., 2012). Since sea cucumbers are commonly poached or illegally traded, there is a need for confirmation and establish a standardized fast, easy to be applied and cheap protocol for taxonomic identification such as spicule analysis to effectively evaluate traded marine organisms, especially in the processed state of sea cucumber. It is therefore important to confirm and to study if the ossicle morphology is changing during the stages of maturity of Holothuria scabra Jaeger in order to provide a guide for developing fishery management plans, conservation, or recovery strategies. Spicule analysis is a different approach to characterize a sea cucumber based on the morphology of ossicles. It was reported that these ossicles can remain undamaged and fully distinguishable even if the sea cucumber is already in a processed state (Torres et al., 2019).

In this light, the researchers aimed to contribute to describing and distinguishing the morphology of ossicles present in the dorsal and ventral regions of Holothuria scabra Jaeger in order to determine if there is a change in the ossicle morphology as the sandfish matures.

Reference

Agudo N. 2006. Sandfish Hatchery Techniques. Australian Centre for International Agricultural Research (ACIAR), the Secretariat of the Pacific Community (SPC) and the WorldFish Center

Al- Yaqout A, Manickam N, Al-Yamani F, Al-Kandari M. 2021. Sea cucumbers of the Arabian Peninsula and Iran a- Review of Historical and Current Research Trends. Saudi Journal of Biological Sciences.

Al-Rashdi KM, Claereboudt MR, Eeckhaut I. 2012. A Manual on Hatchery of Sea cucumber Holothuria scabra in the Sultanate of Oman. Ministry of Agriculture and Fisheries Wealth, Aquaculture Centre. 27 pp.

Althunibat O, Hashim RB, Taher M, Daud JM, Ikeda MA, BIZ. 2009. In Vitro Antioxidant and Antiproliferative Activities of Three Malaysian Sea Cucumber Species. European Journal of Scientific Research 37(3), 376-387.

Bordbar S, Anwar F, Saari N. 2011. High-Value Components and Bioactives from Sea Cucumbers for Functional Foods- A Review. Marine Drugs 9, 1761-1805.

Brown EO, Perez ML, Garces LR, Ragaza RJ, Bassig RA, Zaragoza EC. 2010. Value Chain Analysis for Sea Cucumber in the Philippines. Studies & Reviews 2120. The WorldFish Center 44.

Choo PS. 2008. The Philippines: A Hotspot of Sea Cucumber Fisheries in Asia. In Sea cucumbers. A global review of fisheries and trade, eds. V. Toral-Granda, A. Lovatelli, and M. Vasconcellos,. FAO Fisheries and Agriculture Technical Paper 516, pp. 119-140.

Conand C. 2004. Present status of world international sea cucumber and utilisation: An overview. In Lovatelli, C. Conand, S.W. Purcell, S. Uthicke, J.-F. Hamel, & A. Mercier (Eds.), Advances Management in Sea Cucumber Aquaculture and FAO Fisheries Technical Paper 463, 13-23. FAO.

Dabbagh AR, Sedaghat MR. 2012. Breeding and rearing of the sea cucumber Holothuria scabra in Iran. SPC Beche-de- mer Information Bulletin

Dar M, Ahmad H. 2006. The feeding selectivity and ecological role of shallow water holothurians in the Red Sea. SPC Beche-de-mer Information Bulletin

De Jesús-Navarrete A, Poot MNM, Medina-Quej A. 2018. Density and population parameters of sea cucumber Isostichopus badionotus (Echinodermata: Stichopodidae) at Sisal, Yucatan. Latin American Journal of Aquatic Research 46(2), 416-423.

Ehsanpour Z, Archangi B, Salami M, Salari MA, Zolgharnein H. 2016. Morphological and Molecular Identification of Holothuria (Selenkothuria) parva from Bostaneh Port, Persian Gulf. Indian Journal of Geo- Marine Sciences 45(3), 405-409.

Gamboa R, Gomez AL, Nievales MJ. 2004. The status of sea cucumber fishery and mariculture in the Philippines. Fao fisheries technical paper.

Hamel JF, Conand C, Pawson D, Mercier A. 2001. The sea cucumber Holothuria scabra (Holothuroidea: Echinodermata): Its biology and exploitation as Beche-de-mer. Advances in Marine Biology 41, 129-223.

Han Q, Keesing J, Liu D. 2016. A Review of Sea Cucumber Aquaculture, Ranching, & Stock Enhancement in China. Reviews in Fisheries Science & Aquaculture 24(4), 326-341.

Iradel C. 2022. Sustaining the Culture of Quality in Teacher Education Institutions. Journal of Education Naresuan University 24(2).

Jontila JB, Balisco RA, Matillano J. 2014. The Sea cucumbers (Holothuroidea) of Palawan, Philippines 1, 2. AACL Bioflux, 7(3).

Junus S, Kwong PJ, Khoo G. 2018. A review on the recent advances in the biology and aquaculture technology of Holothuria scabra. Journal of Survey in Fisheries Science 4(2), 5-25.

Kamarudin KR, Rehan MM, Bahaman NA. 2017. Morphological and Molecular Identification of Sea Cucumber species Holothuria scabra, Stichopus horrens, Stichopus ocellatus from Kudat, Sabah, Malaysia. Pertanika J. Trop. Agric. Sci. 40(1), 161-172.

Macfadyen G, Huntington T, Cappell R. 2009. Abandoned, Lost or Otherwise Discarded Fishing Gear. UNEP Regional Seas Reports and Studies No.185; FAO Fisheries and Aquaculture Technical Paper No. 523. Rome: FAO.

Mamelona J, Pelletier E. 2010. Producing High Antioxidant Activity Extracts from Echinoderm by Products by using Pressured Liquid Extraction. Biotechnology 9(4), 523-528.

Massin C, Mercier A, Hamel JF. 2000. Ossicle change in Holothuria scabra with a discussion of ossicle evolution within the Holothuriidae (Echinodermata). Acta Zoologica (Stockholm) 81, 77-91

Mohsen M, Yang H. 2021. Sea Cucumbers: Aquaculture, Biology, and Ecology.

Olavides RD, Edullantes CM, Juinio- Menez M. 2010. Assessment of the sea cucumber resource and fishery in the Bolinao-Anda reef system. Science Diliman 22(2)

Pangestuti R, Arifin Z. 2017. Medicinal and health benefit effects of functional sea cucumbers-A Review. Journal of Traditional and Complementary Medicine. 1-11.

Perez J. 2011. Species Identification of Sea cucumber (Holothuroids) in Guang- Guang, Pujada Bay, Mati Davao Oriental using Spicules. 11th National Symposium in Marine Science.

Pitogo KM, Sumin J, Ortiz A. 2018. Swallow-water Sea Cucumbers (Echinodermata: Holothuroidea) in Sarangani Bay, Mindanao, Philippines with Notes on Their Relative Abundance. Philippine Journal of Science.

Purcell S, Hair C, Mills D. 2012. Sea cucumber culture, farming and sea ranching in the tropics: Progress, problems and opportunities. Aquaculture 368-369, pp.68-81.

Purcell S, Mercier A, Conand C, Hamel J, Toral-Granda M, Lovatelli A, Uthicke S. 2011. Sea cucumber fisheries: global analysis of stocks, management measures and drivers of overfishing. Fish and Fisheries 14(1), pp. 34-59.

Rasolofonirina R, Jangoux M. 2005. Appearance and development of skeletal structures in Holothuria scabra larvae and epibiont juveniles. SPC Beche-de-mer Information Bulletin #22, pp.6-9.

Ross R. 2019. What Is Sea Cucumber? Retrieved from:https://www.livescience.com/sea- cucumbers. html? fbclid =IwAR2QjDJUJZQ lxGIqHEs 83YB 45m5z7AblpMM8FpxOG aRIpmo7Bc7UGAcH6y4

Stricker S. 1986. The Fine Structure and Development of Calcified Skeletal Elements in the Body Wall of Holothurian Echinoderms. Journal of Morphology.

Sun J, Hamel J, Gianasi B., Mercier A. 2019. Age determination in echinoderms: first evidence of annual growth rings in holothuroids. The Royal Society Publishing.

Susetya IE, Dewinta AF, Harahap ZA, Leidonald R, Yusni E, Suriani M, Lesmana I. 2020. Characteristics of environment and habitat of sea cucumbers in Pane Island, Tapanuli Tengah Regency. IOP Conf. Ser.: Earth Environ. Sci 454

Toral-Granda MV. 2005. The use of calcareous spicules for the identification of the Galapagos sea cucumber Isostochopus fuscus on the international market. SPC Beche-de-mer Information Bulletin 22, 3-5.

Torres JRD. 2017. Antibacterial and antifungal property of extracts derived from the body wall and cuvierian tubules of Pearsonothuria graeffei Semper (Black- spotted Sea cucumber). Frontiers in Medicinal Chemistry and Drug Discovery 2(1), 010-018.

Torres JRD. 2015. The Calcareous Spicules of Two Common Sea Cucumber Species Found in La Union, Philippines. Philippine Society for the Study of Nature Book of Abstracts and Proceedings IConSIE ISSN No. 2449-4178; IPR No. O2014-1919.

Torres JRD, Malaya V. 2021. Mitodepressive and Genotoxic Potential of Crude Body Wall and Cuvierian Tubule Extracts of Mani-mani (Pearsonothuria graeffei Semper) on Root Meristems of Onion (Allium cepa L.). Mindanao Journal of Science and Technology Vol. 19.

Torres JRD, Malaya VN, Argame VM, Tadifa FG. 2019. The body wall spicule formations of mature Holothuria impatiens found in La Union, Philippines. Journal of Natural and Allied Sciences 3(1), 42-45.

Tresnati J, Yasir I, Syafiuddin Aprianto R, Yanti A, Bestari AD, Tuwo A. 2020. Early maturity of Sandfish Holothuria scabra offers more prospective broodstock supply of a commercially important aquaculture species. IOP Conf. Ser.: Earth Environ. Sci. 564.

Wolkenhauer SM, Uthicke S, Burridge C, Skewes T. 2010. The ecological role of Holothuria scabra (Echinodermata: Holothuroidea) within subtropical seagrass beds. Journal of the Marine Biological Association of the UK 90(02), 215-223.

Yaghmour F, Whittington-Jones B. 2017. First record of Holothuria (Metriatyla) scabra Jaeger, 1833 (Echinodermata: Holothuroidea) from the coastal waters of the United Arab Emirates. Peerj

Yang H, Hamel JK, Mercier A. 2015. The Sea Cucumber Apostichopus japonicus: History, biology, and Aquaculture, Developments in Aquaculture and Fisheries Science 39, pp.

Yoshimura K, Iketani T, Motokawa T. 2012. Do regular sea urchins show preference in which part of the body they orient forward in their walk? Mar Biol. 159, 959-965.

Source : Ossicle morphology of Sandfish (Holothuria scabra Jaeger) at different stages of maturity