University of Guilan Aquatic Physiology and Biotechnology 2345-3966 6 2 2018 09 22 Effects of dietary supplementation of synthetic astaxanthin on reproductive performance of giant freshwater prawn (Macrobrachium rosenbergii) Effects of dietary supplementation of synthetic astaxanthin on reproductive performance of giant freshwater prawn (Macrobrachium rosenbergii) 65 86 3050 10.22124/japb.2018.8286.1186 FA Ghasem Rashidiyan M.Sc. in Fisheries, Fisheries Department, Natural Resources Faculty, University of Tehran, Karaj, Iran Gholamreza Rafiee Professor in Fisheries Department, Natural Resources Faculty, University of Tehran, Karaj, Iran Mohammad Ali Nematollahi Associate Professor in Fisheries Department, Natural Resources Faculty, University of Tehran, Karaj, Iran Kamran Rezaei Tavabe Assistant Professor in Fisheries Department, Natural Resources Faculty, University of Tehran, Karaj, Iran Journal Article 2017 07 15 The present study was carried out to investigate the dietary effects of different levels of synthetic astaxanthin on reproductive performance of giant freshwater prawn (<em>Macrobrachium rosenbergii</em>). 24 broodstock prawns were randomly distributed into 3 treatments considering male to female ratio as 1:3 in duplicates. Experimental diets were supplemented with an amount of 0 (as control), 50 and 100 mg.Kg^-1 astaxanthin. Prawns were fed on experimental diets in a ratio of 2% biomass for a period of 45 days. Total carotenoid, number of eggs per gram, eggs diameter, hatching rate and number of larvae after hatching as broodstock reproductive performance indices while larval somatic index (LSI) and larval length were measured to assess larval quality. Results showed that diet supplementation with synthetic astaxanthin significantly affects the number of eggs and number of larvae after hatch (P<0.05). Also, a significant difference was observed in total carotenoid, eggs diameter, LSI and larval length (P<0.05). Thus, based on these results and being more cost-effective 50 mg.Kg^-1 supplementation level is recommended to improve giant freshwater prawn reproductive performance.   The present study was carried out to investigate the dietary effects of different levels of synthetic astaxanthin on reproductive performance of giant freshwater prawn (<em>Macrobrachium rosenbergii</em>). 24 broodstock prawns were randomly distributed into 3 treatments considering male to female ratio as 1:3 in duplicates. Experimental diets were supplemented with an amount of 0 (as control), 50 and 100 mg.Kg^-1 astaxanthin. Prawns were fed on experimental diets in a ratio of 2% biomass for a period of 45 days. Total carotenoid, number of eggs per gram, eggs diameter, hatching rate and number of larvae after hatching as broodstock reproductive performance indices while larval somatic index (LSI) and larval length were measured to assess larval quality. Results showed that diet supplementation with synthetic astaxanthin significantly affects the number of eggs and number of larvae after hatch (P<0.05). Also, a significant difference was observed in total carotenoid, eggs diameter, LSI and larval length (P<0.05). Thus, based on these results and being more cost-effective 50 mg.Kg^-1 supplementation level is recommended to improve giant freshwater prawn reproductive performance.   https://japb.guilan.ac.ir/article_3050_91ebbd218413b13243cde90694321057.pdf