Improvement of livebearer fish reproductive performance using Oocyte Developer (OODEV)

Livebearer fish have a unique reproduction by internal fertilization without supplied nutrition from parents. However, increasing the frequency of spawning remains unknown. Therefore, the study aimed to improve reproductive performance by expanding the spawning frequency in three livebearer fish species: guppy, black molly, and platy. Four sets of 10 fish (6 females and 4 males) aged 80 days after birth were maintained in controlled media at 25-28 °C in the separated tank sized 20x20x15 cm. All the fish were fed commercially and mixed with oocyte developer (OODEV) for 14 days at satiation. By using the same fish, spawning and rematuration were observed for 30 and 45 days respectively. The reproductive performance was evaluated for 45 days. The OODEVtreated broodstock showed birthing the larvae in all tanks on the 7th day after treatment, while control fish displayed on the 14th day. The percentage of pregnant broodstock was 66.6-100% in each tank, indicating the OODEV-supplemented diet can be used to increase oocyte growth in the gonad. In the rematuration experiment, the fish spawned a 3-fold increase in frequencies of spawning. These data suggested that OODEV can stimulate oocyte growth and increase the birthing frequency in livebearers.