Masculinization of beta fish larvae Betta splendens through the different treatment immersion of honey solution and larval age

Abstract

Betta fish Betta splendens have morphological differences between males and females. Male betta fish have more attractive body colors and shapes than females. This causes the selling value and market demand for males to be higher than that of females. Therefore, it is necessary to make efforts to get enough male fish through masculinization. So far masculinization or the sex reversal into males using androgen hormones before sex differentiation occurs. However, the use of steroid hormones has been banned and reduced, because they cause environmental and public health problems and are carcinogenic. This study used natural honey solution to determine the effect of length immersion time in the honey solution and to obtain a suitable larval age for masculinization on the early gonadal formation and larval survival after treatment. Masculinization was carried out using larvae in three treatments immersion time as follows 10 hours, 11 hours, 12 hours, and control. After that, the treatment was continued with the best results of the treatment using 7-day old larvae (D7), D9, and D11. Each treatment using 30 larvae was immersed in a honey solution of 3 liters with a concentration of 5 ml / L. The treatments were kept until 60 days before sex observation. Early observations of gonad formation were carried out after the larvae were D20 with HE-stained histology. The data obtained were analyzed using descriptive statistics and a chi-square test. The results showed that the treatment for 12 hours of immersion had the highest male sex ratio (93%). While the treatment on D7 larvae age in honey solution had the highest percentage in males (96%). It can be concluded that the increase in the percentage of male betta fish is influenced by the length of time immersion in the honey solution and the age of the larvae in the first week after hatching. All treatments did not affect the survival of betta fish larvae.