Judul: Masculinization of Nile Tilapia (Oreochromis niloticus) By Immersion Technique in Purwoceng (Pimpinella alpina) Extract
Abstrak: Masculinization of in nile tilapia is very important in controlling reproduction and obtaining gender that have faster growth. Synthetic steroids which are commonly used to masculinize but has potential hazards and not recommended for aquaculture. The use of natural product is a potential alternative to be explored, especially from plant. The objective of this study was to determine the effect of immersion nile tilapia larval in extract of purwoceng in masculinizing nile tilapia. Doses used in this study are 10, 20, 30 mg/l of purwoceng extract with two control groups those are using 500 μg/l 17α-methiltestesterone and no immersion in purwoceng extract. Exposing 8h on 4 and 7 days post-hatching in extract of purwoceng and 17α-metiltestesterone, resulted in significantly skewed sex ratio of 73,3% males by immersion in 20 mg/l. Synthetic androgen, 17α-methiltestesterone gave better result than extract of purwoceng in this study. Further study on extract of purwoceng is needed to observe the best limit of short-time immersion and to find the best result in sex ratio.
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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%.
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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