Production And Quality Of DHA Fortified Eggs By Dietary Chia Seeds And Functional Additives

Docosahexaenoic acid(DHA)is a kind of polyunsaturated fatty acid(PUFA),which is beneficial to human health,such as brain-development and retinal function.But it cannot be directly enriched in human body.It can only be obtained by ingesting food.Fortunately,eggs are an excellent source.DHA in egg yolk is regulated by the?-3 PUFA in the feed of laying hens.Therefore,DHA enriched eggs can be obtained by adding the substance containing?-3PUFA in the feed of laying hens,thus providing an important way for people to obtain DHA.In this experiment,chia seeds were selected as an important source of?-3 PUFA to enrich DHA,and 6 kinds of functional additives(curcumin,alfalfa,tea polyphenols,vitamin E,vitamin B₆,and vitamin C)were selected to explore the effects on production performance,egg quality,fatty acid composition,and DHA deposition efficiency.It was expected to be beneficial for egg production enterprises to produce DHA fortified eggs.The main research contents and results were as follows:(1)This experiment was conducted to explore the effects of dietary levels of chia seeds on production performance,egg quality,fatty acid composition,and DHA deposition efficiency.Two hundred 26-week-old Hy-line brown laying hens were randomly divided into 8 groups with 5 replicates in each group and 5 hens in each replicate group,0%(control group,w/w,same as below),3%,6%,9%,12%,15%,18%and 21%chia seeds,respectively.The pre-experiment lasted for 1 week and the experiment lasted for 8 weeks.The results showed that:a)Compared with the control group,the feed conversion rate of 9%and 15%chia seeds groups and the average egg weight of 21%chia seeds group decreased significantly(P<0.05)but the feed conversion rate of 6%and 12%chia seeds groups increased significantly(P<0.05).In addition,other groups had no significant effect on production performance;b)Compared with the control group,the eggshell thickness of 18%,the yolk percentage and egg yolk ratio of 21%chia seeds groups and the eggshell percentage of 18%chia seeds group were significantly decreased(P<0.05),while the albumen percentage of 21%chia seeds group was significantly higher than that of control group(P<0.05).Besides,other groups had no significant effect on egg quality;c)Chia seeds could increase the content of DHA and?-3 PUFA in eggs after the experiment.Except for the 21%chia seeds group,the other experimental groups were able to achieve the A level of DHA fortified eggs after 4 weeks(120 mg/100 g),even the AA level(150mg/100 g)at the 5th and 7th week;d)DHA deposition efficiency decreased with the level of chia seeds increasing.The DHA deposition efficiency was 0.097±0.003 with dietary 3%chia seeds,and 0.043±0.002 with dietary 6%chia seeds,respectively.However,when the level was over 6%,the deposition efficiency decreased significantly.When the level was 21%,the DHA deposition efficiency was 0.014±0.001,which was nearly 85%lower than that of the 3%chia seeds group.(2)This experiment was conducted to study the effects of dietary 6 functional additives(curcumin,alfalfa,tea polyphenols,vitamin E,vitamin B₆,and vitamin C)on production performance,egg quality,fatty acid composition,and DHA deposition efficiency.Two hundred64-week-old Hy-line brown laying hens were randomly divided into 8 groups with 5 replicates in each group and 5 hens in each replicate group.Based on dietary 6%chia seeds,30 mg/kg curcumin,3%alfalfa,0.3%tea polyphenols,50 mg/kg vitamin E,40 mg/kg vitamin B₆ and 50mg/kg vitamin C were added,respectively.The pre-experiment lasted for 1 week and the experiment lasted for 4 weeks.The results showed that:a)Based on the level of 6%chia seeds,the average egg weight of dietary 0.3%tea polyphenols and 50 mg/kg vitamin E were significantly higher(P<0.05).Meanwhile,dietary 30 mg/kg curcumin could significantly increase the daily feed intake(P<0.05).Besides,other groups had no significant effect on production performance;b)Based on the level of 6%chia seeds,the albumen percentage of dietary 30 mg/kg curcumin,0.3%tea polyphenols,and 50 mg/kg vitamin C were significantly higher(P<0.05).Also,there was no significant effect in egg quality among other groups;c)After the experiment,the contents of DHA and?-3 PUFA in dietary functional additives groups were higher than that in the group of dietary 6%chia seeds without functional additives,especially dietary 30 mg/kg curcumin,40 mg/kg vitamin B6,and 50 mg/kg vitamin C(P<0.05).With dietary 6%chia seeds and 6 kinds of functional additives,the eggs could meet the standard of DHA fortified eggs(120 mg/100 g)and even reached the AAA level(200 mg/100 g);d)Based on the level of 6%chia seeds,dietary 30 mg/kg curcumin,0.3%tea polyphenols,40mg/kg vitamin E,and 50 mg/kg vitamin C could significantly improve DHA deposition efficiency(P<0.05).More significantly,curcumin and vitamin C groups increased from0.046±0.002 to 0.075±0.006 and 0.076±0.005,respectively.According to dietary levels of chia seeds,it was found that the lower level could not only enrich DHA in eggs but also ensure the production performance and egg quality from negative effects.This might be beneficial for egg production enterprises to produce DHA fortified eggs.On this basis,it was found that dietary curcumin and vitamin C can improve the DHA deposition efficiency without affecting the production performance and egg quality to improve the DHA enrichment in eggs.For this reason,it could produce DHA fortified eggs with AA or AAA level.In the long term,it can reduce the feed cost for egg production enterprises to produce high-quality DHA fortified eggs that meet the recommended intake of DHA.