Effects of crude palm oil supplementation on tocopherol and tocotrienol concentrations in blood, adipose tissue, liver, egg yolk and cholesterol concentration in egg yolk of laying hens

Abstract

Effect of crude palm oil (CPO) on vitamin E (tocopherol and tocotrienol) concentrations in blood, adipose tissue, liver and egg yolk was examined. The study was divided into 2 experiments. A preliminary trial (experiment I) was designed to examine the adverse effect of CPO in layer chicken. Ten, 48 weeks old, Hisex laying hens were equally divided into two experimental groups, control (0% CPO) and 2% CPO group. Parameter on hen performance, egg performance and egg quality at weeks 0-6 and cholesterol concentration in egg yolk at weeks 4, 5 and 6 were determined. The result showed that CPO had no effect on daily feed intake, hen weight. There was no significant difference in egg specific gravity and yolk color in control group and CPO group. Egg weight and yolk weight of CPO group were significantly higher than control group at weeks 3 and 6 (egg weight) and weeks 5 and 6 (yolk weight) (P<0.05). Cholesterol concentration in egg yolk was slightly decreased in CPO group. In experimental II, 144 hens, 49 weeks old, Hisex hens were equally divided into 4 groups receiving 4 different treatment diets. The treatment diets included CPO at 0 (control), 2 ,3 and 4%, respectively. Egg performance, hen performance and egg yolk cholesterol (weeks 0, 4, 5 and 6) were examined as described in experiment I. Egg yolk, adipose tissue (abdominal fat), plasma and liver of laying hens were determined for tocopherol and tocotrienol concentrations using HPLC. The results demonstrated that weight gain, daily feed intake, hen-day basis percentage, specific gravity, albumin quality, albumin weight and shell weight were not different among experimental groups. CPO increased egg yolk color, egg weight (approximately 2 g), yolk weight (approximately 2 g) when compared to control group. CPO significantly decreased egg yolk cholesterol in weeks 4-6 of the experiment with the lowest level in hens fed on 4% CPO (11.89 mg/g yolk). CPO enhanced (P<0.05) total tocopherols in CP01 (2% CPO) and total tocotrienols, especially CP02 (3% CPO) and CP03 (4% CPO) groups. Hens fed on CPO 3 (4% CPO) had the lowest total tocopherols in egg yolk and adipose tissue but had the highest tocotrienol in plasma, egg yolk and adipose tissue when compared with other groups. CPO supplementation resulted in the highest deposition of tocotrienol in adipose tissue compared to egg yolk, liver and plasma. In conclusion, CPO had no adverse effect on performance of laying hen. Supplementation of CPO at 3 and 4% improved FCR of hen and significantly increased egg yolk color, egg weight and yolk weight. CPO significantly reduced egg yolk cholesterol. Laying hens supplemented with CPO (4% CPO) had more vitamin E deposited in egg yolk and adipose tissue than control with the highest level of α-tocopherol, α- and γ-tocotrienol.