The Effect Of Eggs Containing Cr On Growth,Gut Ratio And Blood Biochemical Parameters Of Rats

Cr is an important and indispensable trace element. The study was concerning how Cr deposit in eggs, what effect Cr was on both the laying function of layers and the yolk cholesterol and Cr and eggs containing Cr on the growth of rats, ratio of organs to body and blood biochemical parameters, which would help to probe into preliminarily the possibility of health function of Cr and to provide the theoretical basis for application of Cr to livestock products.This experiment was divided into two parts. One (Experiment 1) was to add CrY (Chromium Yeast) with different levels to the food of layers and the other (Experiment 2) was to add eggs containing Cr and CrY to food of rats.In Experiment 1,1×5 factorial experimental device was employed in which 160 healthy Roman layers of 49 weeks old were divided into 5 groups at random, in which there were two repeats with16 layers in each repeat. The first group, as contrast part, were given food daily without Cr while the other groups, as experimental groups, were given food containing CrY with different levels. The effects of the Cr with different levels on laying function and yolk cholesterol were studied. The deposit of Cr in eggs was also determined so as to find out the deposit rules. Result shows that the experimental groups fed the diet containing 400ug/kg CrY had higher laying rate than that of the contrast group. The egg weight increased significantly (p<0.05) and the food consumption decreased sharply (p<0.05) . The food containing Cr with different levels reduced the yolk cholesterol content strikingly. Cr could deposit in eggs. At the 21^st day of the experiment, the deposit content grew with the increase of Cr content in feed. The difference between the contrast group and the experimental groups was striking (p<0.01) . There was marked difference among the experimental groups as well (p<0.05). Compared with the Cr deposit in eggs at the 21^st day, the Cr deposit in eggs at the 35th day had a fall on the average, but still higher than that of the contrast group (p<0.05) . At the 49th day of the experiment, there was no remarkable difference in Cr deposit in the experimental groups compared with that of the 35th day.The 2X5 factorial experimental device was employed in the experiment of adding eggs containing Cr and CrY to the food of rats. Ninety healthy male rats of about 180 grams were divided into 9 groups at random, in which there were two repeats in each group with 5 rats in each repeat. One group, as a contrast group, were fed daily diet without Cr and eggs of contrast group in Experiment 1. To the food in Group 1 to 4 was added eggs containing Cr with different deposit in Experiment 1 while to the food in Group 5 to 8 was added CrY with different dose and eggs in contrast group of Experiment 1 in which the eggs is 30% of the total part. Experimental duration was 40 days with the study of what effects eggscontaining Cr and Cr with different levels were on the growth of mice, ratio of organs to body, and blood biochemical parameters. The result strongly demonstrates that the differences of weight were striking (P<0.05) between the rats in contrast group and the ones fed food with CrY and eggs containing Cr in other groups. The increase of Cr in blood serum was in proportion to that of Cr content in food. Compared with the contrast group, the amount of blood sugar, total cholesterol, triglyceride and low density of lipoprotein cholesterol had the index of decline while high density of lipoprotein cholesterol rose gradually. There was a striking decline (P<0.05 ) of blood sugar, total cholesterol, triglyceride and low density of lipoprotein cholesterol between the rats of experimental groups of 5, 6, 7, 8 and of contrast group, Group 1, 2, 3 and 4. The high density of lipoprotein cholesterol increased strikingly ( PO.05 ) . There was no significant difference among the contrast group and Group 1, 2, 3 and 4, the same result with Group5, 6 ,7, 8. There was no striking difference ( P>0.05 ) of the ratio of organs to body between the rats in contrast group and the ones in experimental groups, but the ratio of spleen to weight in experimental group rats had the index of rise.This data reveals that the feed added 400ug/kg CrY could improve laying rate, the average weight and reduce the ratio of feed to eggs. The feed added 400—800ug/kg CrY could lower cholesterol content in yolk significantly. Within 21 days the Cr deposit in eggs grow with the increase of CrY added to the feed but decreased a bit since the 22nd day. The Cr deposit content in eggs added 400ug/kg CrY in all the groups remained consistent. The more Cr content the rats got, the higher level the Cr content in the blood serum remained. The feed added Cr would lower blood sugar, total cholesterol, triglyceride and low density of lipoprotein cholesterol, but increase high density of lipoprotein cholesterol, which would slow down the growth of weight. The eggs that layers laid by feeding on diet added 400⁸00ug/kg CrY would reduce blood sugar, total cholesterol, triglyceride and low density of lipoprotein cholesterol in rats less evidently than that in rats fed CrY directly. The high density of lipoprotein cholesterol in rats increased with less degree than that in rats fed CrY directly.