Abstract

The present study was conducted to investigate the effects of feeding different levels of aniseed (Pimpinella anisum L.) medicinal plant as a natural biological feed additive on feed intake, feed conversion ratio, egg production, egg weight, egg yolk cholesterol concentrations, serum cholesterol and triglyceride concentrations of laying hens. This experiment was carried out in a completely randomized design with 240 Hy-Line (W36) hens divided into 4 treatment groups with 3 replicates (20 birds in each replicate) for 8 weeks from 80 to 88 weeks of laying period. Dietary treatments were as follows: T₁ (control group, basal diet with no aniseed), T₂ (basal diet plus 0.2% aniseed), T₃ (basal diet plus 0.4% aniseed) and T₄ (basal diet plus 0.6% Aniseed). The analysis of variance of the data indicated that using this medicinal plant in different levels had statistical differences in terms of feed intake, feed conversion ratio, egg weigh and egg yolk cholesterol concentrations in the different experimental groups (P<0.05). The highest amount of feed intake (1887g) wasobserved in group 4 with 0.6% aniseed, while the lowest level of egg yolk cholesterol (75.92 mg/g yolk) and the best feed conversion ratio (2.8) were observed in group 3 with 0.4% aniseed. Also, the group 2 with 0.2% aniseed showed the highest egg weigh (75.66 g). On the other hand, the use of aniseed medicinal plant did not have any significant effect on egg production and the concentration of blood cholesterol and triglyceride of laying hens (P>0.05). Therefore, it was concluded that the aniseed medicinal plant could be used up to 4% level in laying hens diet with beneficial effects on performance. However, it is not recommended to be used at 6% level because of its negative effects on feed conversion ratio (3.3), egg yolk cholesterol concentration (133.45) and blood cholesterol concentration (250.3).

Key words: Laying hens, parameter, aniseed (Pimpinella anisum L.), medicinal plant.