Performance of Whiteleg Shrimp (Litopenaeus vannamei) with Additional of Dolomite to the Feed

Abstract

The objective of this study was to analyze the use dolomite in diet of whiteleg shrimp. It was conducted in June to August 2018 at the hatchery of Pangkep State Polytechnic of Agricultural. Experimental design used a completely randomized analysis with 4 treatments, A (control), B, C, and D with the additional of dolomite at dose 4, 8, and 12 mg/kg, respectively with 3 replications. Animal test were PL 25 from the shrimp hatchery in Barru District and acclimatized before stocking in aquarium (30l), with density of 20 ind., reared for 40 days, fed pellets (30% protein, 10% biomass, 5 times). The molting intensity (MI) determined by observing and counting the number of moulting every day. Observation of growth rate (GR) using a digital scale (0.0001 g) and survival rate (SR) by calculated the number of live shrimps at the end of the study. Water quality parameter included temperature, salinity, DO and pH. Analysis of Variance (ANOVA) was performed to evaluate the effect of treatment on MI, GR, and SR and followed with the Least Significant Difference (LSD) Test.  ANOVA for MI, GR, and SR revealed that dosage have different significant (P<0.05) and LSD test showed that the dose was not optimal (only differentiated between those given dolomite). The highest of MI (avg. 18 inds.), GR (1.82% /day), and SR (78.33%) were obtained in C and the lowest one obtained in A.  Data of water quality obtained temperatures 29.87-31.03°C, salinity 25-30 ppt, DO 4.86-5.51 mg/l which were still in the proper range. The highest pH value was obtained in D was 7.22-7.75, while the lowest one obtained in A 6.95-7.16. The highest MI, GR, and SR were obtained in C, temperature, salinity, DO, and pH are still in the proper for the growth and survival of shrimps.