58 DECEMBER 2024 • WORLD AQUACULTURE • WWW.WAS.ORG could explain the poorer growth performance obtained in treatment four where the stocking density was highest. Average daily length gain and weight gain were significantly different across all treatments (Table 2, Figures 15 and 16). Mean specific growth rate was also significantly different (P<0.05) across treatments. As seen above, with increasing stocking densities growth was reduced (Table 3, Figure 17). Weight gain means were significantly different (P<0.05) by the second week. And, length gain values of T1 and T2 were significantly different from those of T3 and T4, and each other (P<0.05). Because S. spilurus has an oval, moderately compressed and fairly deep body, length gains were high at the beginning. In the fourth week, weight gain values of T1 and T2 were again significantly different from those of T3 and T4, and from each other (p<0.05), and only the mean length gain of T1 was significantly different from other treatments’ (P<0.05). In the sixth week, only T1 and T4 were significantly different in weight and length gains (P<0.05). As well, in the eighth week both weight and length gain of T1 and T4 were significantly different from those of T2 and T3 and each other (P<0.05). Length and weight gains throughout the study are shown in Tables 4 and Table 5, respectively. Survival was high for all treatments (Table 6 and Figure 20). During the study period the pH range was 7.1 to 8.6, temperature range was 25°C to 30°C and dissolved oxygen levels were between 6.9 and 7.6 mg/L. Conclusions The results of this study confirmed that the stocking density of 0.75 PL/L was the best treatment for maximizing early growth of Systomus spilurus fry in captivity, while stocking at 2.25 PL/L resulted in the highest output in terms of numbers. Notes Dissanayake, D.K.S.D.* and Athauda, A.R.S.B., Department of Animal Science, Faculty of Agriculture, University of Peradeniya, Sri Lanka; Walpita, C.N., Department of Livestock Production, Faculty of Agricultural Sciences, Sabaragamuwa University of Sri Lanka; Mudalige, A.R., National Aquaculture Development Authority of Sri Lanka, Aquaculture Development Center, Dambulla. * Corresponding author: asf16010@agri.pdn.ac.lk References Chakraborty, B., Mirza, Z., Miah, M., Habib, M., & Chakraborty, A. (2007). Reproductive Cycle of the Endangered Sarpunti, Puntius sarana (Hamilton, 1822) in Bangladesh. Asian Fisheries Science, 20(2), 145–164. Retrieved from https://doi.org/10.33997/j. afs.2007.20.2.002 Department of Census and Statistics Ministry of Economic Policies and Plan Implementation. (2021). Gross Domestic Product (GDP) by production Approach. Retrieved from http://www. statistics.gov.lk/Resource/ en/NationalAccounts/2010/ reports/Production/2021.07.09/ detail_note_2021q1_en FAO. (2017). In FAO 2017 (Vol. 5). FAO. (2020). The State of Food and Agriculture: Overcoming Water Challenges in Agriculture. In The State of Food and Agriculture 2020. Gupta, S. (2015). A Review on Feeding and Breeding Biology of Systomus sarana ( Ham.-Buch., 1822); A Threatened Fish of Indian Subcontinent. [7(4), 295–301]. Retrieved from https://doi.org/10.5829/idosi.wjfms.2015.7.4.95147 Mohanty, B. P., Mahanty, A., Ganguly, S., Mitra, T., Karunakaran, D., & Anandan, R. (2019). Nutritional composition of food fishes and their importance in providing food and nutritional security. Food Chemistry. Retrieved from https://doi.org/10.1016/j. foodchem.2017.11.039 Mudalige, A., Walpita, C., Athauda, A., Perera, S. J., & Chandrarathna, P. (2022). Initial success of captive breeding and larval rearing of endemic fresh water food fish. AgInsight. Retrieved from http://repo.lib.sab.ac.lk:8080/xmlui/bitstream/ handle/susl/3443/2022_Mudalige_etal_Systomus_spilurus_capt_ breeding_Aginsight.pdf?sequence=1&isAllowed=y National Aquaculture Development Authority of Sri Lanka. (2018). Annual Report. Retrieved from http://www.naqda.gov.lk/ pdf/2020/Annual%20report%202018%20English.pdf Pethiyagoda, R., Meegaskumbura, M., & Maduwage, K. (2012). Ichthyological Exploration of Freshwaters. A synopsis of the South Asian fishes referred to Puntius (Pisces: Cyprinidae), 23(1), 69–95. Reviews in Aquaculture. (2009). Global aquaculture and its role in sustainable development. Retrieved from https://doi.org/10.1111/ j.1753-5131.2008.01002.x Subasinghe, R., Soto, D., & Jia, J. (2009). Global aquaculture and its role in Sustainable Development. Reviews in Aquaculture, 1(1). https://doi:10.1111/j.1753-5131.2008.01002.x Udit, U., Reddy, A., Kumar, P., Rather, M., Das, R., & Singh, D. (2014). Induced breeding, embryonic and larval development of critically endangered fish Puntius sarana (Hamilton, 1822) under captive condition. Journal of Animal and Plant Sciences (24(1), 159–166.). FIGURE 20. Survival of S. spilurus fry during the study period. Means with the same letters indicate no significant differences between treatments.
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