frequency on growth performance and RNA:DNA ratio in Mystuscavasius (Hamilton, 1882) fingerlings

Abstract

Mystuscavasius(Hamilton, 1882)is one of the most important aquaculture fish species and it is popularly cultured in all over Bangladesh. The fish is widely consumed by the people for their rich protein content and essential fatty acids. So a study was conducted to estimate the growth performance like growth performance, survival rate, condition factor, average daily gain (ADG), specific growth rate (SGR) and percentage of weight gain (%) of Mystuscavasius.To estimate the effects of different feeding frequency on growth performance of gulsha an experiment was conducted for 90 days in the 12aquarium under four treatments located at the Department of Fisheries, University of Dhaka. Each aquarium was filled with 18 fingerlings. The fingerlings were fed with one .two, three and four times feeding in a day respectively. The fingerlings were fed at the rate of 5% of their body weight.The study was conducted during the month August to October 2016. Water quality parameters were observed weekly and the results were more or less similar in four treatments and remained within the suitable ranges for aquaculture. During the rearing and feeding trail in the laboratory condition, the change in growth and feed utilization by the gulsha fish feed on four times different feeding frequency have been assessed by the determination of condition factor (K), average daily gain(ADG), specific growth rate (SGR), survival rate and feed conversion ratio (FCR).The treatmentsare significantly differentwas found in feeding frequency. The highest FCR (2.69±0.26) was found in treatment 4 (four times feeding per day) while the lowest FCR(1.68±0.04) was found in the treatment 2(two times feeding per day).The value of Average Daily Gain(ADG) was found highest (0.30±0.017) g/day in treatment 3 (three times feeding per day) and the lowest ADG (0.08±0.008) g/day was found in treatment 4. The values of SGR were highest (11.90±0.02) % for the treatment 3 and lowest (0.76±0.02)% in treatment 4.The condition factor was highest (1.61±0.018) in treatment 2 while the lowest (1.05±0.02) condition factor was found in treatment 1.Condition factor of treatment two was significantly diferent than others treatment.The highest survival rate (93.25±0.47)% was observed in the treatment 4 belonged to 60th day culture period and the lowest survival rate (83.32±5.55)was found in the treatment 4 belonged to 30th day culture period. Result from RNA: DNA ratio indicates the growth performance of gulsha fish. The highest RNA:DNA ratio (0.93±0.07)was observed in the treatment 2 (TR2) whereas the lowest(0.57±0.11) ratio was observed in the treatment 1(TR1).