Effects of different dietary oils on production performance,egg quality,and plasma biochemical parameters of laying hens
This study investigated the effects of different dietary oils on egg production performance,egg quality,and plasma biochemical indicators of laying hens.A total of 252 Hy-Line Brown laying hens at 330 days of age were chosen and randomly divided into 3 groups ac-cording to the principle of approximate equal egg production,with 7 replicates in each group and 12 replicates in each group.The groups were the control group(the soybean oil group),the lard group and the palm oil group.The experiment spanned over a period of eight weeks,dur-ing which the feed intake,egg weight,egg production rate and feed to egg ratio of the birds were recorded.Their egg quality,yolk fatty acid composition and plasma biochemical parameters were detected.The results showed that,compared with the control group(the soybean oil group),the addition of lard and palm oil significantly reduced the average egg weight(P<0.01)and significantly increased the feed to egg ratio(P<0.01)of the tested hens,and the addition of palm oil also significantly increased their average egg production rate(P<0.01).Re-garding egg quality,there was no significant difference between adding lard or palm oil and adding soybean oil(P>0.05).In terms of egg yolk fatty acid composition,the addition of lard and palm oil significantly decreased the content of egg yolk peanut oil acid(C20:1)and heneicosanoic acid(C21:0)(P<0.05),significantly reduced the content of polyunsaturated fatty acids(PUFA)(P<0.01),and signifi-cantly increased the content of monounsaturated fatty acids(MUFA)(P<0.01),while the addition of lard significantly raised the content of egg yolk oleic acid(C18:in-9(t9),C18:1n-9(c9))(P<0.01)and arachidonic acid(C20:4n-6)(P<0.05).Adding palm oil significantly increased the content of egg yolk saturated fatty acids(SFA)(P<0.01)and myristic acid(C14:0)(P<0.05)in the hens,and significantly decreased their content of unsaturated fatty acids(USFA)(P<0.05).In terms of blood biochemical indicators,the addition of lard and palm oil significantly lowered the concentration of alkaline phosphatase(ALP)(P<0.01)and glucose(GLU)(P<0.05)in the blood plasma of the laying hens,but adding palm oil significantly raised the concentration of alanine aminotransferase(ALT)(P<0.01)in them.Different oil additives(lard and palm oil)significantly reduced the average egg weight and increased the feed to egg rati-o,palm oil significantly increased the average egg production rate of laying hens.To sum up,different oil additives(lard and palm oil)to the diet of the laying hens significantly improved their fatty acid composition of egg yolk and significantly reduced their plasma alkaline phos-phatase and glucose concentrations,but palm oil significantly raised the plasma alanine aminotransferase concentration in the hens.