Judul: Degradasi Asam Fitat pada Kambing Peranakan Etawah Laktasi yang Mendapat Ransum Bersuplemen Kedelai Sangrai, Vitamin dan Mineral
Abstrak: Phytic acid is a chelating agent which has been known as an anti nutrition that binds minerals and reduces their biological availability. The purpose of the research was to observe phytic acid degradation and its relation with mineral absorption and dry matter digestibility, and to evaluate the relation of dry matter digestibility determining by total collection method with that of AIA (acid insoluble ash) method. Eight Etawah Grade lactating goats were allocated to two groups and to dietary treatments of suplemented ration. Lactating goats in treatment 1 and treatment 2 groups were offered a complete feed without or with additional roasted soybean, vitamin A, D, E, and mineral cromium (Cr) organic, and selenium (Se). Phytic acid degradation in treatment 1 goats did not differ from that of treatment 2 goats. Roasted soybean, vitamin and mineral supplementation had no effect on phytic acid degradation. Relationship between phytic acid degradation and nutrient digestibility indicated that degradation of phytic acid had positive corelation with dry matter and crude fiber digestibility, but had not significant corelation with neither crude protein nor crude fat digestibility. Phytic acid was highly degraded in ruminant digestive tract (86,32±3,49%). The degradation phytic acid and mineral absorption indicated that phytic acid degradation had no effect on mineral absorption. Total collection methode had no effect corelation with AIA methode.
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Judul: Mineral pada Susu Kambing Peranakan Etawah yang Diberi Ransum Bersuplemen Kedelai Sangrai, Selenium, Kromium, Vitamin A, Ddan E
Abstrak: Milk from Etawah grade goatsis known as an alternative source of animal protein and provides better nutrients than cow’s milk. However,the dairy goat in Indonesia has low productivity. Goat may be exposed to heat stress and therefore nutrient intake is not adequate for optimum milk production. This study was designed to evaluate the efficiency of mineral, roasted soybeans, and vitamin supplementation in lactating goats. Eight Etawah gradegoat were allocated randomly to two dietary treatments. Experimental diet were a complete diet without supplement (treatment 1) and diet supplemented with roasted soybeans (280 g/kg),selenium (0.5 ppm),cromium (3 ppm),vitamin A (8000 IU/kg), vitamin D (1500 IU/kg), dan vitamin E (400 IU/kg). Feed intake, mineralabsorption, andmilkmineral content were observed. The results showed that the suplementation of minerals and vitamins in a complete ration did not affect feed intake, mineral absortion and mineral component in the dairy goats. It was concluded that supplementation of roasted soybeans, selenium, chromium, vitamin A, D and E in lactating goats did not influence absorption and secretion of the mineral in milk of Goats. The improvement of feed quality in feeding Etawah grade goats was important tosupport high production and quality of milk.
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Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
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