Abstract
In this study, the effects of the addition of pomegranate seed oil (PSO) at different levels (0, 0.5, 1, and 1.5 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> ) to laying-hen rations on performance values, egg quality criteria, egg shelf life, some enzyme activity, and the fatty acid composition of yolks were investigated. In the study, 96 Lohman LSL laying hens at 64 weeks of age were used. The trial consisted of four groups, each containing 24 hens. Chickens were given feed and water ad libitum during the 8-week experiment. The first group was the control group and was fed with a basal diet, while the other groups were fed with feeds with 0.5, 1.0, and 1.5 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> PSO added to the basal feed, respectively. The lowest feed consumption and the highest egg weight were determined in the 1 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> PSO group. The highest feed conversion ratio, the lowest eggshell weight, and the shell-breaking strength were determined in the 0.5 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> PSO group. It was determined that the egg yolk malondialdehyde (MDA) value in the groups to which pomegranate seed oil was added was significantly lower than the control group on the 28th day of storage. The lowest glutation (GSH) and catalase values were found in the control group, and the highest total antioxidant capacity (TAC) was found in the 1 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> PSO group. It was determined that the addition of PSO to the diet significantly increased the rate of saturated fatty acids (SEFA), conjugated linoleic acid (CLA), and conjugated linolenic acids (CLnA) in yolk. The results showed that the addition of 1 mLkg−1mLkg-1<math><mrow><mi>mL</mi> <mspace></mspace> <msup><mi>kg</mi> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </mrow> </math> pomegranate seed oil to the feeds decreased feed consumption, increased egg weight, and positively affected the shelf life of the egg. In short, the addition of PSO had a positive effect on shelf life, and it increased punicic acid and CLA levels without reducing egg quality.