This experiment was conducted to investigate the effect of feeding duration of diets containing corn distillers dried grains with solubles (DDGS) on productive performance, egg quality, and lutein and zeaxanthin concentrations of egg yolk in laying hens. A total of 300 57-week-old Hy-Line Brown laying hens were randomly assigned to one of 5 treatment groups (feeding duration) with 6 replicates consisting of 5 consecutive cages with 2 hens per cage. Diets were formulated to contain either 0% (the control diet) or 20% DDGS. Experimental diets were fed to hens for 12 wk. The feeding duration of diets containing 20% DDGS was 0, 3, 6, 9, or 12 wk before the conclusion of the experiment. Feeding the diet containing 20% DDGS for 3, 6, or 9 wk followed feeding the control diet for 9, 6, or 3 wk, respectively. The data for productive performance were summarized for 12 wk of the feeding trial. Results indicated that increasing feeding duration of diets containing 20% DDGS had no effects on productive performance of laying hens, but increased egg yolk color (linear, P < 0.01), hunter a* value (linear and quadratic, P < 0.01), and b* values (linear, P < 0.05) with a decrease in hunter L* value (linear and quadratic, P < 0.05). Lutein and zeaxanthin concentrations of egg yolks also were increased (linear, P < 0.01) by increasing the feeding duration of diets containing 20% DDGS. In conclusion, feeding diets containing 20% DDGS to laying hens has no adverse effects on productive performance. Increasing the feeding duration of diets containing 20% DDGS improves egg yolk coloration with a concomitant increase in lutein and zeaxanthin concentrations of egg yolks in laying hens.

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1. Thiols have been implicated to play a role in a variety of aspects of nitric oxide (NO) generation and activity. Thiol dependence of nitric oxide synthase (NOS) has remained controversial and its mechanism is not clear. This study investigates possible mechanisms between thiol (SH group) and NOS activation, through thiol compounds (glutathione, dithiothreitol, N-acetyl-L-cysteine) and Ebselen [2-phenyl-1,2-benzisoselenazole-3(2H)-one] on rat aortic vascular responses. 2. In rat thoracic aorta, acetylcholine (10(-6)-10(-9) M) induced a relaxation of phenylephrine (PE) (10(-7) M)-induced tone, which was inhibited dose dependently by increasing concentration of ebselen (1-10 microM). 3. In rings of rat thoracic aorta, ebselen and NOS inhibitors (NG-monomethyl-L-arginine, NG-nitro-L-arginine methyl ester) produced an augmentation of phenylephrine (10(-7) M)- induced tone and acetylcholine induced a relaxation of PE (10(-7) M)-induced tone in rat thoracic aorta, which was inhibited by ebselen (10 microM) like NOS inhibitor. 4. The thiol compounds (glutathione, dithiothreitol, and N-acetyl-L-cysteine) alone did not change vascular tone in rat thoracic aorta. Pretreatment with thiol compounds before ebselen treatment, however, reversed the inhibitory effect of ebselen which acts like the NOS inhibitor in rat thoracic aorta. Posttreatment with thiol compounds after ebselen treatment did not reverse the inhibitory effect of ebselen by as much as pretreatment. 5. Calcium ionophore A23187 (10(-7) M)-induced vasodilation was inhibited in ebselen pretreated rat thoracic aorta, but sodium nitroprusside (SNP, 10(-7) M)-induced relaxation was not inhibited by ebselen. This suggests that NOS is involved in the inhibitory effect of ebselen on rat thoracic aorta relaxation. 6. These results suggest that ebselen exerts an inhibitory action on the nitric oxide synthesis in rat thoracic aorta by interacting with thiol groups.

The miscibility and phase behavior of ternary blends containing dimethylpolycarbonate (DMPC), tetramethylpolycarbonate (TMPC) and poly[styrene‐co‐(methyl methacrylate)] copolymer (SMMA) have been explored. Ternary blends containing polystyrene (PS) instead of SMMA were also examined. Blends of DMPC with SMMA copolymers (or PS) did not form miscible blends regardless of methyl methacrylate (MMA) content in copolymers. However, DMPC blends with SMMA (or PS) blends become miscible by adding TMPC. The miscible region of ternary blends is compared with the previously determined miscibility region of binary blends having the same chemical components and compositions. The region where the ternary blends are miscible is much narrower than that of binary blends. Based on lattice fluid theory, the observed phase behavior of ternary blends was analyzed. Even though the term representing the Gibbs free energy change of mixing for certain ternary blends had a negative value, blends were immiscible. It was revealed that a negative value of the Gibbs free energy change of mixing was not a sufficient condition for miscible ternary blends because of the asymmetry in the binary interactions involved in ternary blends. Copyright © 2004 Society of Chemical Industry