Judul: Evaluation of Pine Pollen Extract Dietary Supplementation on Masculinization and Reproduction Performance of Guppy (Poecilia reticulata)
Abstrak: Freshwater ornamental fish potential in Indonesia continues to increase, mainly male guppy (Poecilia reticulata) due to more beautiful color than female fish and more expensive price, which needs an effort to increase male percentage. Masculinization using androgenic synthetic hormone such as 17α-methyltestosterone is the most common way to increase total male fish produced. However, this hormone has several problems, namely high-cost import material and is thought to have a negative impact for the environment. Pine pollen (PP) is a highly potential material for organic androgenic source containing phytohormone or phytoandrogenic hormone. The aim of this study was to evaluate dietary supplementation of pine pollen extract fed during pregnant broodstock, larvae, and broodstock candidate phase on masculinization and reproduction performance of guppy fish. This study contained three steps, namely SSP extract dietary supplementation during pregnant broodtsock, larvae, and broodstock candidate phases. First step study was performed by evaluating the PP extract dietary supplementation in pregnant broodstock on the breed male sex ratio produced. This study used 5 treatments and 3 replications as each treatment unit was filled with 1 pregnant broodstock at 0.8-1 g broodstock-1 weight and 3.5-4.5 cm length. Treatments used were control (K), 1 mg kg-1 feed 17α-methyltestosterone (MT), 10 mg kg-1 feed SSP extract (SSP10), 50 mg kg-1 feed PP extract (SSP50), and 250 mg kg-1 feed SSP extract (SSP250). The feed available for pregnant broodstock was fed 3 times a day for 15 days at satiation. Parameters identified in this study were first- (B1) and second-born (B2) male sex ratios, B1 and B2 survival rates, broodstock testosterone hormone concentration on B1, broodstock estradiol level on B1, gonadosomatic index (GSI) on B1, hepatosomatic index (HSI) on B1, B1 and B2 birth difference, number of larvae produced by each broodstock, and testis and ovarium histology on B1 and B2. In the B1, the study results showed that the SSP250 treatment produced the highest male sex ratio at 66.40%, and had insignificant difference on survival rate (P>0.05). In the B2, the male sex ratio in control and PP treatments was insignificantly different. In the B1 and B2, the MT treatment obtained the highest male sex ratio compared to other treatments (P<0.05). The 17α-methyltestosterone residue still likely remained on 1-month after treatments were terminated. This condition induced the ongoing masculinization in the B2. The supplementation of SSP extract and MT certainly improve the plasma testosterone content either in broodstock or larvae. The first study step concludes that the dietary supplementation of SSP extract can increase the male sex ratio of guppy fish at 32.6% with 50 mg kg-1 feed as the optimal dose. The second study step was performed to evaluate the dietary supplementation of SSP extract in larvae on male sex ratio. This study contained 5 treatments and 3 replications filled with 20 0-3 days after birth larvae. Treatments applied were similar to the first study step. Feeding was performed at satiation 3 times a day for 15 days. Parameters identified were male sex ratio, survival rate, GSI, HSI, and testis and ovarium histology. The study results showed that SSP extract supplementation
Keyword: masculinization, pine pollen, Poecilia reticulata, reproduction performance, 17α-methyltestosterone