Judul: Efektivitas Ekstrak Tepung Testis Sapi Dalam Alih kelamin Ikan Nila, Oreochromis Niloticus L. Melalui Teknik Perendaman
Abstrak: Monosex fish stocks are desirable in aquaculture in order to control reproduction and select the gender that have faster growth characteristics in a particular species. Synthetic steroids are commonly used to sex-reverse tilapia but because of their potential hazards and not recommended in Indonesia; the use of new natural compound is a potential alternative to be explored. Bull testes meal extract (BTME) had knowed containing natural testosterone hormone which can used on sex reversal in fish. The objective of this study was to determine the efficacy of a short-term immersion procedure for masculinizing Nile tilapia,_Oreochromis niloticus. Two androgens hormone were evaluated: 17a-methyltestosterone as control part (synthetic androgens) and the other is BTME as natural androgen. Exposure (8 h) on 4 and again on 7 days post-fertilization to 17a-methyltestosterone at 500 μg/ l successfully masculinized fry in all replicated experiments, resulting in 81,11% respectively. Immersions in BTME at 1 ml/l (Experiments A) resulted in significantly skewed sex ratios in (68,89 %), and Experiments B (3 ml/l) resulted in 75,56 % males; and Experiments C (5 ml/l) resulted in 85,56 % males. Although further research and refinement is needed, immersion of Nile tilapia in BTME may provide a practical alternative to the use of natural steroid-treated immersion. Furthermore, when compared with current techniques for steroid-induced sex inversion of tilapia, short-term immersion reduces the period of time that workers are exposed to anabolic steroids.
Keyword: 

Judul: Maskulinisasi Ikan Nila Oreochromis niloticus Dengan Pemberian Tepung Testis Sapi
Abstrak: The synthetic steroid 17α-Methyltestosteron (MT) is commonly used as a feed additive to produce male population of nile tilapia (Oreochromis niloticus). The use of synthetic testosterone hormone is not recommended in Indonesia. This study was conducted to evaluate the effect of natural testosterone hormone in bull testes meal (BTM) on the masculinization of nile tilapia. Experimental design that is utilized two factors experiments in completely randomized design. Fry kept in 40-L glass aquaria at a density of 40 fry/aquarium. Fry (7 dph) received the BTM for 7 days (T1), 14 days (T2) and 21 days (T3) and doses 0% (D1), 3% (D2), 6% (D3), and 9% (D4). Result, indicated that there were significant (P<0.05) differences between group treated by BTM and untreated group. In the BTM treated group, doses and duration of treatments are not significantly different. The percentage of male fish on the three treatments was 83.3% (9%-14d, 9%-21d, 6%-21d: doses and duration, respectively), higher than the other groups but not significantly different with all treated group. There were no significant difference on the survival rate of fry (95-99.5%) between all treatments. Survival rate was not affected by the treatment of BTM (not significant P≥0.05). The body growth rate were not different between BTM treated groups and untreated group. The highest growth performance of fry was obtained by the treatment of 9% BTM. Conclusion, the best of treatment is D3T2 (6% BTM and 14 days), resulted male fish 81.67%.
Keyword: 

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf