The effect of cosmos caudatus extract on the survival rate of litopenaeus vannamei post larvae against salinity

Differences of salinity in fishponds could influence the survival rate of Litopenaus vannamei in the post larval life stage. They can cause stress, inhibit growth, and can even lead to the death. However, this condition can be overcame by using Cosmos caudatus extract, which has the potential to reduce oxidative stress in L. vannamei. The aim of this study was to determine the effect of Cosmos caudatus extract on the survival rate of L. vannamei post larvae. The effects were observed under salinity stress with the purpose of knowing the optimal dose of the extract that can be used. This study used a completely randomized design. There were 5 treatments with 4 replications of each treatment. The treatments consisted of several doses of C. caudatus extract, namely 7 mL, 14 mL, 21 mL, negative control without C. caudatus extract, and positive control with vitamin C. The data was analyzed using the ANOVA test. The results show that a dose of 14 mL of C. caudatus extract was the best dose to improve the survival of L. vannamei post larvae. It can be concluded that C. caudatus extract could improve the survival rate of L. vannamei post larvae under salinity stress.