Judul: Altering physiological conditions and semen acidity by manipulating dietary cation-anion difference and their effect on sperm characteristics of garut breed rams
Abstrak: This study was carried out to evaluate the effect of dietary cation-anion difference (DCAD) and fish oil supplementation on dry matter intake, dry matter and organic matter digestibility, weight gain, acidity of urine, blood and semen, blood gas, plasma mineral, sperm characteristics and ratio of X:Y spermatozoa. The dietary treatmens were as follows: RN0= basal ration (DCAD +14) without fish oil, RNI= basal ration (DCAD +14) with 3% fish oil, RB0= base ration (DCAD +40) without fish oil, RBI= base ration (DCAD +40) with 3% fish oil, RA0= acid ration (DCAD -40) without fish oil, and RAI= acid ration (DCAD -40) with 3% fish oil. The rations contained 150 ppm of zinc and were offered to 18 of Garut breeed rams. The result indicated that: DCAD +40 and -40 decreased dry matter intake significantly. The ration with DCAD +40 had the lowest dry matter intake. No differences were observed for dry matter and organic matter digestibility. DCAD +40 and -40 decreased body weight of rams except RA0 ration, however, the body weight of rams was very low. Variation of urine pH followed the DCAD pattern. Blood pH, pCO2, and pO2 were not affected by DCAD, but cHCO3 and cBase were affected. DCAD affected plasma Mg and S, but did not affect K, Na, Zn and Cl. Semen pH after day 28 of experimental period were significantly different and that followed DCAD pattern. There were not differences for X:Y ratio, macroscopic and microscpic characteristic of sperm.
Keyword: dry matter intake, semen PH, sperm characteristics, basal ration, West Java

Judul: Semen quality of garut rams fed by different protein sources and their implementation potential assessment in small farms of West Java.
Abstrak: Excellent protein quality is absolutely required and plays an important role in the reproduction process, particularly in improving the quality of sperm for supporting the prolific nature of Garut rams. Maggot Hermetia illucens (Maggot Black Soldier Fly, MBSF) is an alternative protein source besides soybean meal (SBM) which have used as a feed. The aims of this study were to analyzed and compare the impact of different protein sources in feed on semen quality of Garut rams, and to assess the potential integration of these feeds into the small-scale breeders of West Java, Indonesia. These experiments consist of two phases; laboratory phase and breeding farms survey phase. The first phase of this study was conducted using a completely randomized design with 3 treatments and 4 replications. Treatment on this study was Brachiaria humidicola (BH) grass and T1 (concentrate contains 20% of SBM), T2 (concentrate contains 10% of SBM and 10% of MBSF), and T3 (concentrate contains 20% of MBSF). The parameters were feed consumption, semen quality (macroscopic and microscopic characteristics), also a potential ability of rams to serve females. The second phase was conducted in Garut, West Java, Indonesia as the concentration region of Garut rams, and assessing smallscale breeders who were potentially able to extend the feeding practical with MBSF, using a questionnaire as guidance. The first results showed there was no significant effect of the feeds (P>0.05) on protein nutrient consumption, semen volume, semen pH, semen color and consistency, sperm mass movement, sperm motility, sperm concentration, total number sperm per ejaculate, sperm morphology, sperm viability, sperm plasma membrane integrity and potential ability to serve females. However, the result showed a significant effect (P<0.05) on sperm viability and sperm membrane integrity. Sperm plasma membrane integrity of ram feed with T3 was better than T1 and T2. The potential ability rams to serve ewes on MBSF treatment was 38 heads, while in T1 and T2 were 43 and 57 heads respectively. The second results of the breeding farms survey explained there are two types of groups that are able to develop maggot BSF as feed based on indicators, i.e. income per month, experience, educational level, and numbers of animals. There are five categories of breeders who can apply MBSF on their farms but only four farmers from two categories were expected to be able to intergrate MBSF into their systems. The conclusion of our overall study is MBSF can be an alternative source of protein, besides soybean meal to improve the semen quality thus supporting the prolific properties of Garut rams.
Keyword: Garut rams, semen quality, maggot BSF, protein

Judul: Bifurkasi lokal pada titik tetap non-hiperbolik
Abstrak: Bifurkasi menggambarkan perubahan pada struktur orbit di sekitar titik tetap. Titik tetap dibagi menjadi dua yaitu titik tetap hiperbolik dan titik tetap non-hiperbolik. Titik tetap non-hiperbolik terjadi jika ada nilai eigen dengan bagian real sama dengan nol. Kestabilan dari titik tetap dapat diketahui dari nilai eigen yang diperoleh dari pelinearan medan vektor. Pada bifurkasi satu-dimensi ditemukan kasus-kasus untuk bifurkasi saddle-node, bifurkasi transcritical dan bifurkasi pitchfork. Bifurkasi saddle-node terjadi jika satu sisi dari nilai parameter tidak terdapat titik tetap dan pada sisi lain terdapat dua titik tetap, dimana yang satu stabil dan yang lainnya tak-stabil. Bifurkasi transcritical terjadi jika terdapat pertukaran kestabilan, yaitu dari titik tetap stabil menjadi titik tetap tak-stabil dan sebaliknya. Sedangkan bifurkasi pitchfork dibagi menjadi dua, yaitu: bifurkasi pitchfork supercritical dan bifurkasi pitchfork subcritical. Bifurkasi pitchfork supercritical terjadi jika satu titik tetap stabil berubah menjadi dua titik tetap stabil dan satu titik tetap tak-stabil, dan bifurkasi pitchfork subcritical terjadi jika satu titik tetap stabil dan dua titik tetap tak-stabil berubah menjadi satu titik tetap tak-stabil. Bifurkasi Hopf (bifurkasi dua-dimensi) terjadi jika terdapat orbit periodik pada struktur orbitnya yang berupa lingkaran dengan jari-jari konstan. Ada atau tidaknya orbit periodik dapat diketahui setelah sistem ditransformasikan ke dalam koordinat polar. Orbit periodik ini dapat bersifat stabil maupun tak-stabil. Model periklanan (advertising) Feichtinger merupakan salah satu contoh penerapan bifurkasi Hopf Model ini menghasilkan satu titik tetap dan orbit periodik yang bersifat stabil.
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