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The objective of this experiment was to determine the effects of dietary fiber levels on growth performance, gizzard development, intestinal morphology, and nutrient utilization in Cherry Valley meat ducks. In total, 720 1-day-old ducklings were fed with starter diets (120 ducklings, 8 pens of 15 ducklings, on each diet) containing 6 levels of crude fiber (CF, 1.46, 3.09, 4.15, 6.18, 7.52, and 9.03%, based on analysis) for 21 d. Then, on d 22, ducks fed all of the starter diets were transferred to a grower diet (containing 4% CF) to examine the residual effect of starter dietary fiber levels until 35 d. Body weight (BW), body weight gain (BWG), feed intake (FI), feed to gain ratio (F:G) were recorded/calculated weekly. Ducks were sampled for gizzard development and intestinal morphology determination on d 7, 14, and 21. Nutrient utilization was assessed using 25- to 27-day-old ducks. The results showed that BW (d 21), BWG (d 15 to 21, d 1 to 21), and F:G (d 15 to 21, d 1 to 21, and d 1 to 35) were increased quadratically (P < 0.01), and FI (all periods except for d 22 to 35) was increased linearly (P < 0.01), when starter dietary CF levels increased from 1.46 to 9.03%. Ducks under 3.09% and 4.15% CF starter diets had decreased 1 to 35 d FI and F:G when compared to ducks under other starter diets. When compared to ducks fed 1.46% and 3.09% CF starter diets, ducks fed starter diet containing 7.52% CF had increased gizzard development, jejunal morphology, energy retention, excreta nutrients availability, and standardized ileal digestibility (SID) of Arg, Ile, Leu, Thr, Val, Asp, Ala, Glu, Gly, Pro, Ser, and total amino acids. In conclusion, meat ducks from 1 to 21 d of age could adapt to a wide range (3.09% to 7.52%) of dietary fiber levels. [ABSTRACT FROM AUTHOR]

L10 phase FePt thin films deposited on MgO (100) single-crystal substrate with good (001) texture were investigated. Epitaxial growth of the FePt (001) films was observed with a deposition temperature of 400 °C. With ultrathin Ag intermediate layers deposited between FePt layers, the film structures changed from an interconnection network to an isolated-island character. The perpendicular coercivity of the FePt film dramatically increased from 6.5 to 32.5 kOe. The improvement of the magnetic properties may be attributed to the formation of island structures by the additive Ag in the FePt films. [ABSTRACT FROM AUTHOR]