Effect of dietary addition of Flaxseed and fish oil on Laying performance, egg yolk fatty acids and cholesteral in yolk and serum of Laying hens

Abstract

This trial was conducted to investigate the effect of dietary addition of flaxseed and fish oil on productive performance, egg yolk fatty acid composition, and on cholesterol levels in yolk and blood serum of laying hens as well as sensory evaluation of eggs. In total, 200 laying hens were divided into 5 groups. Ten birds were randomly assigned to each treatment (5 cages) and each treatment was replicated 4 times. The birds were fed a standard layer diet (17% CP; 2800 Kcal/ME/kg diet). The diets contained 0-0, 10-1.5, 15-1.5, 10-3.0 and 15-3.0% combinations of flax seed to fish oil in FS0FO0, FS10FO1.5, FS15FO1.5, FS10FO3.0 and FS15FO3.0 treatments, respectively. When compared to the controls, only FS15FO3.0 hens consumed more feed per day (P<0.01) ; thus, feed conversion ratio of the controls was better (P<0.01) than those of the FS15FO3.0 groups. There were no significant differences in egg weight, egg mass and egg production among treatment groups. The level of MUFA of the yolk decreased progressively when dietary FS and FO increased (P<0.01). The addition of FS and FO significantly decreased the level of η-6 FAs, but the level of η-3 FAs (LNA, EPA, DPA and DHA) increased linearly and significantly with increasing FS and FO levels in diets (P<0.01). Consequently, the ratios of PUFA:SFA in the treated groups were significantly higher than those of the controls whereas the ratios of Ση-6: Ση-3 were significantly lower (P<0.01). The yolk cholesterol significantly decreased progressively with the increasing levels of dietary FS and FO when compared to the control (P<0.01). Apart from FS10FO1.5 hens, it was shown that serum cholesterol level significantly decreased by increasing FS and FO in diets (P<0.05). There were no significant difference in sensory evaluation of eggs among groups (P>0.05).