Comparison of effects of Green tea on Blood parameters, egg quality, carcass characteristics and growth performance in Japanese quails fed high- or nonecholesterol diets

In order to investigate the effects of green tea leaf powder (GTL) on blood parameters, egg quality, carcass characteristics and growth performance, one hundred and sixty 14d-old Japanese quails (male and female) arranged in a 2×2 factorial design (2 levels of GTL, and 3% and 2 levels of dietary cholesterol, 0 and 10g/kg)in form of a complete block design with 4 treatments and 4 replicate with 10 birds in each and then the quails were treated under the 4 dietary treatments during a 31-day experimental period. The treatments include: 1) Control, 2) Control+10g/kg Cholesterol, 3) diets include 3% GTL and 4) diets include 3% GTL+1 g/kg Cholesterol. Feed intake and weight gain were recorded during experiment. At the end of the experimental period 2 bird from each cage randomly selected for blood sampling and the blood and serum were sampled for determining of blood HGB, HCT, MCV, MCH, MCHC, RBC, WBC, Heterophile, Lymphocyte, Monocyte, eosinophils and basophils count and serum triglyceride, cholesterol, LDL, HDL, VLDL. Two birds from each cage were selected and slaughtered and the relative weight of carcass, viscera’s, testes, breast muscle, thigh muscle, gizzard, heart, liver, pancreas, duodenum, jejunum, ileum, cecum and head were recorded. For evaluation of muscle and egg quality the cholesterol contents of breast and thigh muscle and yolk were assayed and for more egg quality assessment 10 eggs from each replicates were assayed and the percent of albumin, yolks, egg shell, edible components of egg, egg shape index, egg shell thickness, and egg shell surface were determined. Results indicated that GTL inclusion in the diets resulted in increase of duodenum weight(P<0.001), jejunum weight(P=0.004), serum LDL(P=0.001), L:H ratio(P=0.009), Heterophile (P<0.001), yolk cholesterol content(P<0.001), edible components of egg (P=0.035), weight gain of 21- 35d(P=0.008), weight gain of 21-50d(P=0.015), feed intake in21-35d, 35-50d and 21-5 d (P<0.001) and decrease of lymphocyte(P<0.001), breast muscle cholesterol content (P<0.003). Contrary of expectations, cholesterol addition to the diets didn’t raise the serum cholesterol but resulted in increase of jejunum weight (P=0.006), Heterophile (P 0.001), yolk cholesterol content(P=0.012),lymphocyte(P<0.001), feed intake in 35-50d and 21-50d (P<0.001) and also resulted in decrease of lymphocyte(P=0.001) and yolk cholesterol content(P=0.018). The interactions of GTL inclusion and dietary cholesterol addition were significant for Duodenum weight (P=0.001), Heterophile (P<0.001), lymphocyte(P 0.001), breast muscle cholesterol content (P<0.001) and thigh muscle cholesterol content(P 0.002), yolk cholesterol content(P<0.001), feed intake in 21-35d (P<0.001).Therefore, inclusion of GTL in Japanese quails diets cannot be a good cholesterol lowering method from serum and quail products but because of the intestinal reinforcement and therefore persuasion of the growing quails for high feed intake and higher weight gain can be recommendable.