The aim of the present study was to investigate the growth performance of Nile tilapia immersed in 17α-methyltestosterone (MT) and recombinant giant grouper growth hormone (rElGH), and fed a rElGH-enriched diet. A total of 200 tilapia larvae aged 10 days and 14 days post hatching was immersed in 1 liter of 30 g/L saline water for 3 minutes, then in freshwater containing either MT, MT+rElGH, or rElGH for 4 hours. The MT dose was 2.0 mg/L and rElGH was 2.5 mg/L. As control was treatment without MT and rElGH. Fish were maintained in 250-L aquariums for 6 weeks and then moved to net cages for 8 weeks of rearing. The rElGH-enriched diet was fed to the 6-week-old fish for a month, and then fed a non-enriched diet. Each treatment was triplicates. The result showed that the daily growth rate (DGR), biomass gain (BM), survival (SR) and feed (artemia nauplii) consumption during maintenance in the aquariums in the rElGH and MT+rElGH treatments were higher (P<0.05) than in the control. The higher DGR and BM at net cage rearing and lower feed conversion ratio (P<0.05) were also found in MT and MT+rElGH treatments. None of the treatments showed any difference in survival (P>0.05). Profits estimation in the MT and MT+rElGH treatments were 63.38% and 57.91% higher than the control. The present study concluded that higher Nile tilapia farming performance could be obtanied by MT immersion in the larval phase and feeding juvenile on the rElGH-enriched diet.

Banggai Cardinalfish (Pterapogon kauderni) is one of the endemic fish from the waters of the Banggai Islands, Central Sulawesi Province. One factor challenging the production of P. kauderni larvae is the male fish will nurture the eggs and larvae for 30 days, hindering next spawning cycle. One effort to overcome this problem an increase of male fish number should be performed, for example through sex reversal. This study aimed to determine the effectiveness of the hormone 17α-methyltestosterone (17α-MT) through Artemia sp. to increase male sex percentage P. kauderni. This study used a completely randomized design by testing four treatments namely feeding Artemia sp. which has been soaked with 2.0 mg of the 17α-MT hormone for two- hours given to P. kauderni larvae for 10 days (A); 20 days (B); 30 days (C), and without hormone treatment 17α-MT (control). Each treatment included control was performed in triplicates. The percentage of male sex was 93.33 % at 30 days treatment and was higher (P<0.05) compared to controls (53.3 %). Additionally, the results showed that daily growth rate, biomass gain and survival rate of all treatments were not significantly different (P>0.05) with those of control. In conclusion, Artemia sp. contained 17α-methyltestosterone enhanced male percentage of P. kaurderni. Keywords: growth, male percentage, Artemia sp., survival rate, Pterapogon kauderni

This study aims to evaluate the culture performance of tilapia (Oreochromis niloticus) that have been treated with 17α-methyltestosterone (MT) and without MT (w-MT), feed with different protein levels (20, 24, and 28%) and recombinant Epinephelus lanceolatus growth hormone (rElGH)-diet. The research was conducted in 9 treatments and triplicate. Tilapia larvae were soaked twice, totaling 500 larvae, at the age of 10 days after hatching (DAH) and the age of 14 DAH was soaked for 4 hours using 1/l MT 2 mg/l solution. Fish maintenance was conducted in an aquarium of 1.0x0.5x0.5 m3 in the first month, and three months later in net cages (2.0x2.0x1.5 m3). Daily growth rate (DGR) and biomass gain (BG) were increased in line with increasing feed protein content and rElGH supplementation. The highest DGR and BG values were MT+28+rElGH (P 0.05) treatment. The highest feed consumption and the lowest feed conversion ratio were also obtained in the MT+28+rElGH treatment (P 0.05). Fish survival was ranged from 79.89 to 90.28% (P 0.05). The highest profit potential was found in the MT+28+rElGH treatment. The efficient aquaculture can be obtained by feeding sex-reversed tilapia at a protein level of 28% and a diet supplemented with rElGH.Keywords:Feed conversion ratioGrowth hormoneProtein retention17α-methyltestosterone

Ampana City, Tojo Una-Una Regency has the potential of marine tourism and the area also faces a serious threat from the litter that can affect aesthetic value, reduce the quality of waters, intervention to normal systems in the environment. Sampling to the beach in general representative locations in Malotong Beach (area of 100 x 25 m2), and Bailo Beach (100 x 10 m2). The sampling units in the transect plots are 5 plots covering 25 m2 (plot size 1 x 1 m2) randomly determined. The next procedures are the collection and classification of litter. The composition and density of the type of litter are distinguished for meso (0.5cm-2.5cm) and macro (> 2.5cm) litter. The results showed that the type and abundance of the litter that generally comes from recreational activities of beach visitors and household litter. In general, meso and macro litter were found in Malotong Beach as many as 25 types, and in Bailo Beach as many as 35 types. The presence of litter on the coast and the sea threatens life on the Coast of Ampana City. Today’s public awareness is needed to change habits and give more respect to their environment.