Some plant sources rich in compounds with antioxidant activity have been used in the feeding of layers, in the search for improved performance of birds and quality of eggs .found that the inclusion in the feed of 1% of herbs—oregano, rosemary or thyme —or 0.5% of turmeric can improve the productive performance of chickens, benefit the oxidativest ability of eggs and reduce the oxidation of yolk lipids during storage. Ginger has an antioxidant capacity that reduces oxidative stress, inhibiting carcinogenesis . Active ingredients such as tetrahydrocurcuminoids were found in turmeric, according to studies; curcumin, demethoxycurcumin,and bisdemethoxycutcumin have also been found in turmeric . Some studies have been carried out to find out the effects of curcumin on the performance of broilers and laying hens. The antioxidant effect of turmeric has already been reported in the case of broilers.

This effect is closely related to the increase of catalase, hepatic superoxide dismutase, and glutathione peroxidase enzymes . There were no significant differences in egg production and egg weight in egg quality. Contrary,indicated that egg production increased, but egg weight decreased insignificantly by addition of turmericrhizome powder to laying hen diets. According to the authors, turmeric might enhance digestive tract performance in laying hens resulting in the improvement of egg production.were able to observe that turmeric powder extract improved the production performance of Ac “Black bone” hens with better egg mass production and feed: egg conversion from 28 to 34 weeks of age and no change in egg mass.showed that turmeric powder affected egg production significantly, but not egg weight.indicated that production and mass of egg increased by addition of turmeric due to the fact that uterus media could have been improved and result in enhanced shell weight and thickness.Recent research has indicated that there are no differences in the internal quality of eggs from hens fed turmeric.However reported that albumen height and egg protein significantly increased by addition of turmeric.

According to , increase in albumen showed that active substances in turmeric powder stimulated the growth of the epithelial cells and tubulargl and cells in the magnum to synthesize and secrete albumen. At the sixth week, yolk color was lower about 4% in laying hens fed 0.5% turmeric compared with the control group. On the other hand,observed that yolk color increased significantly by the addition of 0.5% dietary turmeric powder. Dietary treatments contend 0.5% of turmeric do not significantly affect blood serum cholesterol, alanine aminotransferase,and aspartate aminotransferase levels.The intestinal mucosa is continuously growing and is affected not only by metabolic hormones, but also by other food-related factors, such as physical and chemical characteristics of nutrients and intestinal microbiot.In a study carried out to determine the effect of the herb mixture ,observed greater depth of crypts in birds that received the herb mixture composed of turmeric powder and fenugreek compared to birds that did not receive, indicating through the crypt depth the body’s attempt to recover the villus structure.

Studies with broilers have revealed that a lower vilo: crypt ratio may indicate the presence of destroyed villi and increased cell proliferation in crypts, resulting from attempts to restore damaged intestinal epithelium,in the occurrence of microbiological challenges in the intestine reported that turmeric in the feed is able to prevent intestinal colonization of inoculated bacteria, indicating that 1% turmeric is able to express its antimicrobial activities, promoting an imbalance in the population of bacteria components of the microbiot and especially against inoculated bacteria. Because of increased incretion of enzymes such as amylase,trypsin, chymotrypsin, and lipase, feed conversion ratio might be improved by turmeric-supplemented diets of laying hens . Moreover, the reason of feed intake increment might be due to turmeric special aroma.indicated that daily feed intake increased by addition of 100 and 200 mg/kg turmericrhizome extract to broilers; but daily feed intake decreased by addition of 300mg/kg. These differences are consistent with the results of and , who added 3% turmeric rhizome powder to laying hen diet. In another study ,feed intake and FCR were reduced by addition of 2% turmeric rhizome powder to laying hen diet. used turmeric powder as a food additive and found a significant increase in the percentage of edible parts, including 0.5%, 1.0% and 1.5% of turmeric powder in the diet, respectively. However, the highest percentage of cuts was 57% . The improvement in carcass weight and edible carcass weight in these experiments is attributed to the antioxidant activity of saffron, as it contains beneficial phytochemicals such as curcumin, AR-turmerones and curlone.