Modulation of Maltose Preference by Selection from Dextrin, Maltose and Glucose Diets in Zinc-Deficient Rats

Abstract

Summary This study examined whether the chain length of glucose in the diet could affect the selection of foods by Zn-adequate and Zn-deficient rats. Dextrin, maltose and glucose were used as sources of carbohydrate in the diet and the selection patterns of the rats were analyzed for 28 d by a 3-choice selection. Diets provided as a set of three either Zn-adequate or Zn-deficient diets were rotated daily. The Zn-adequate control rats selected widely from the three diets throughout the 28 d. In contrast, rats fed a Zn-deficient diet selected exclusively and continuously the dextrin diet or dextrin and glucose diets from the three diets over the experimental periods. The average daily total food intakes of rats fed a Zn-deficient diet were very significantly decreased. The selections of dextrin, maltose and glucose diets in the 3-choice methods of the control rats were 5.7 Ϯ 1.6 b , 5.8 Ϯ 2.0 b and 2.7 Ϯ 0.9 a g/ d, respectively ( p Ͻ 0.05), and those of the Zn-deficient rats were 6.4 Ϯ 2.5 c , 0.8 Ϯ 1.3 a and 2.6 Ϯ 1.4 b g/d, respectively ( p Ͻ 0.05). The ratios of the selected maltose-diet in the Zn-adequate control and the Zn-deficient rats were 40.8 Ϯ 13.8 and 9.0 Ϯ 15.6%, respectively ( p Ͻ 0.01) and those of the dextrin-diet were 40.3 Ϯ 11.4 and 63.0 Ϯ 22.3%, respectively ( p Ͻ 0.05). The decreased preference for the maltose-diet in the Zn-deficient rats may reflect the increased selection of the dextrin-diet.

Change to a Preference for Maltose from Sucrose over Days in Zn-Deficient Rats Selecting from Maltose and Sucrose Diets

“…The preference for maltose in this paper was different from the previous study (23). The Zn-deficient rats changed their preference from sucrose to maltose in this paper but from maltose to dextrin in the selection with a 3-choice method from dextrin, maltose and glucose diets (23).…”

“…2 and 3). With a 3-choice method for selection from dextrin, maltose and glucose diets, Znadequate control rats selected the three diets uniformly, while Zn-deficient rats continued to select the dextrin diet or dextrin and glucose diets (23). From these results, the preference for carbohydrate as well as food selection and feeding patterns in Zn-deficient rats are different from those of Zn-adequate rats.…”

“…The Zn-deficient rats changed their preference from sucrose to maltose in this paper but from maltose to dextrin in the selection with a 3-choice method from dextrin, maltose and glucose diets (23). This discrepancy may be caused by the use of dextrin.…”

“…When dextrin, maltose, sucrose, glucose and fructose are used as a source of carbohydrate in a diet, the food intake of the dextrin group is the highest under either Zn-adequate or Zndeficient diets, and that of the fructose group is the lowest ( 25 ). Using a three-choice method by selection from dextrin, maltose and glucose diets, a decreased preference for the maltose diet is found in Zn-deficient rats ( 23 ). These results suggest that rats have preferences for different kinds of carbohydrate and change their preference under Zn-deficiency.…”