The different effects of heat shock duration and initial period on hatching rate, abnormality rate, egg yolk absorption, and survival rate of spotted barb (Puntius binotatus) larvae

Spotted barb (Puntius binotatus) is one of Indonesian endemic fish with high economic value. However, this fish has slow growth, so innovative technology was required to increase fish growth. This study aimed to determine the different effects of heat shock duration and initial period on hatching rate, abnormality rate, length of egg yolk absorption, and survival rate of spotted barb larvae. This study was used an experimental method using factorial completely randomized design, with two factors of treatment, namely heat shock duration (1, 1.5, and 2 min) and initial period (3, 4, and 5 min after fertilization) of fish embryos. Egg fertilization was conducted artificially. The fish embryo was shocked at the temperature of 40°C. Parameters of hatching and abnormality rates, length of egg yolk absorption period, and survival rate were observed. Data were analyzed statistically using analysis of variance followed Duncan's multiple range test with a confidence level of 95%. The results showed that the fertilization rate of the spotted barb was above 81%. Treatment of heat shock duration and initial period influenced hatching rate of fish embryo, and abnormality and survival rates of larvae; however, treatments have similar lengths of egg yolk absorption in spotted barb larvae.