PROFESSOR OF FMIPA UI DEVELOPS SPERMATOZOA CRYOPRESERVATION WITH NATURAL MATERIALS TO IMPROVE FISH FARMING
Indonesia has the greatest wealth of fish species in the world. Based on the records of the Ministry of Maritime and Fisheries Affairs (KKP), Indonesia has at least 4,720 types of freshwater and seawater fish, or around 25% of the world’s fish population. Of these, there are 650 species of ornamental fish, including the botia fish (Botia macracanthus). This potential can be a strategic value for Indonesia to increase state revenues from foreign exchange through the export of ornamental fish.
Currently, the development of ornamental fish exports is hindered because fish populations in nature tend to decline. This decline occurred due to over fishing, export of juveniles, and habitat destruction due to illegal logging. To continue to meet market demand, fishery production does not only rely on natural populations but also aquaculture production by utilizing breeding technology applications. However, the provision of seeds in this way is constrained by the asynchronous maturation of the gonads between male and female parents.
According to a lecturer and researcher from the Faculty of Mathematics and Natural Sciences (FMIPA) Universitas Indonesia (UI) Prof. Dr. Drs. Abinawanto, M.Sc., cryopreservation of spermatozoa can be a solution in solving this problem. Cryopreservation is a technique for storing genetic material (including spermatozoa) at cold temperatures for a certain period of time. Through cryopreservation methods, cells can be stored for hours to years.
In his scientific oration entitled “Utilization of Natural Cryoprotectants for Cryopreservation of Fish Spermatozoa in Ex-Situ Conservation Efforts”, Prof. Abinawanto mentioned several factors that determine the success of cryopreservation. These factors include the sampling method (how to collect sperm); packaging (a place used to store sperm); diluents (cryoprotectants and extenders); as well as storage temperature to keep sperm cells alive and capable of fertilizing eggs.
The method of collecting sperm samples in fish can be done by stripping (massage) on the abdomen or surgery. With the stripping method, alive spermatozoa can be obtained more, instead of using the surgical method. The stripping method is usually used to collect sperm from goldfish, silver barb fish, and dewa fish.
In addition to the sampling method, the packaging for storing sperm also determines the success of cryopreservation. Cryogenic tubes (2 mL) and straws (0.2 mL) are used to cool the cells. Cryogenic tubes are used to store sperm while straws are used to store embryos (mammals).
Another factor in the success of cryopreservation is the use of diluent to reduce the viscosity of sperm fluid during the storage and to prevent clumping. The diluent solution consists of cryoprotectants and extenders. Cryoprotectant is a solution that protects cells, both from the outside (extracellular) and from the inside (intracellular). Methanol, Glycerol, and Dimethyl sulfoxide (DMSO) are intracellular cryoprotectants, whereas Polyvinyl pyrrolidone (PVP) and Carboxy Methyl Cellulose (CMC) are non-natural extracellular cryoprotectants.
Prof. Abinawanto stressed the importance of utilizing natural extracellular cryoprotectants. Apart from being cheap, natural extracellular cryoprotectants are easy to obtain and use by the community. The examples of natural extracellular cryoprotectants are honey, skim milk, egg yolks, soybean juice, date juice, and brown sugar. Natural cryoprotectants have various effects on spermatozoa based on the type of cryoprotectant used and the species used. Natural cryoprotectants are able to maintain motility, viability, and fertility up to above 80% and reduce abnormalities up to 10–25%.
Apart from being a cryoprotectant, the extender solution is also used as diluent in cryopreservation. Coconut water is a natural extender solution with a motility level of 80.36% for sperm cells of gourami fish. The extender solution contains mineral salts and sugars which function to maintain the physiological condition of cells during the storage.
“My hope in the future is to be able to develop cryopreservation methods using natural ingredients that are easy and inexpensive so that farmers or fish cultivators can use them. This is done so that people can continue cultivating fish practically without the need for expensive equipment,” said Prof. Abiwananto.
Thanks to this scientific study, Prof. Dr. Drs. Abinawanto, M.Sc. was successfully inaugurated as a Ternured Professor in Biology, Department of Biology, FMIPA UI, on Wednesday (14/12). The professor inauguration procession was led by Rector of UI Prof. Ari Kuncoro, S.E., M.A., Ph.D., at Balai Sidang UI, Depok Campus, and was broadcast virtually via UI Youtube channel. The inauguration ceremony were also attended by: President Director of PT Indotech Scientific Asep Sofyan; CEO of Pandu Holding Company Fajar R. Budiman; National Research and Innovation Agency, Prof. (Research) Heny Suseno; and the Dean of FMIPA UI for the 1994–1998 period, Dr. Endang Asijati, M.Sc.
Prof. Abinawanto earned his bachelor degree in Biology at Universitas Indonesia (1986); master degree in Biology at Institut Teknologi Bandung (1993); and doctoral degree in the Department of Animal Science, School of Agricultural Sciences, Nagoya University, Japan (1997). Since 1987, he has been listed as a lecturer and researcher at FMIPA UI. Various researches have been conducted and published in national journals, reputable international journals, and indexed international proceedings.
Several scientific works published by Prof. Abiwananto are The Effects of Brown Sugar as a Natural Cryoprotectant on Tor Soro (Valenciennes 1842) Spermatozoa Quality (2022); Effect of Egg Yolk of Free-Range Chicken and Methanol as a Cryoprotective Agent for the Sperm Preservation of Cyprinid Fish, Neolissochilus Soroides (Valenciennes, 1842) (2021); The Potential of Honey Supplementation in Extender for Preservation of Break Fish (Systomus Orphoides) Spermatozoa (2021); Effect of Cryopreservation on Ultrastructure and Mitochondrial Function of Albino Pangasius Catfish Spermatozoa (2020); and Effect of Honey Solution as a Natural Cryoprotectant on the Sperm Quality of Botia Fish (Chromobotia Macracanthus Bleeker 1852). (2020).
