Induced Breeding of Glass Catfish, Kryptopterus Vitreolus (Ng and Kottelat, 2013)

Abstract

Induced breeding of glass catfish, Kryptopterus vitreolus (Ng and Kottelat, 2013), was carried out at Phitsanulok Inland Fisheries Research and Development Center from September 2018 to November 2018, in order to compare the concentration of human chorionic gonadotropin (HCG) for induced breeding of this species. The experiment consisted of four treatments, in which the female broodstock was injected with HCG at different concentrations to stimulate egg maturation. Then, after 24 h, the females in all treatments were injected with 10 µg·kg^-1 buserelin acetate (BUS) in combination with 10 mg·kg^-1 domperidone (DOM) to stimulate ovulation. Treatment 1 females were injected with 0.9% sodium chloride to serve as a control group. Treatments 2, 3 and 4 females were injected with HCG at 100, 300 and 500 IU·kg^-1, respectively. The male fish were injected only with BUS and DOM, at the same concentrations as the females. The results showed that the female brooders in the control group did not spawn, while 100% ovulation was achieved from females receiving all treatment levels of HCG. Concentration of HCG clearly showed positive influence on most parameters observed, such as readiness of spawning and egg weight. Maximum fertilization rate, hatching rate and survival rate of the fry were found for females injected with 500 IU·kg^-1 HCG, and showed significant differences from other treatments (p<0.05). The eggs of glass catfish were 0.75-0.85 mm in diameter, bright yellow and adhesively attached to substrates. The hatching took approximately 21.30 h at 25.3-26.7 °C. Hatchting larvae were 2.5±0.1 mm in length. It was concluded that 500 IU·kg^-1 HCG with 10 µg·kg^-1 BUS and 10 mg·kg^-1 DOM can result in successful artificial breeding of this species.