Effects of DHA Compound Additives in Diets on Production Performance and Egg Quality of Laying Hens

In order to investigate influence of DHA compound additives in diets on egg quality and production performance, 96 Hy-Line layers were divided into 4 groups at random, and each group consisted of 6 cages with 4 laying hens per cage. GroupⅠ was control group and fed with basal diet. Groups Ⅱ-Ⅳ were experimental groups and fed increasing levels of DHA compound additives at 2%,4% and 8% respectively. Results showed that average laying rate, average egg shape index and average feed/egg ratio of all groups were not significantly different(P>0.05); the average egg mass of groups Ⅱ-Ⅳ were found to be significantly higher than that of groupⅠ(P<0.01) in the whole trial period. Average haugh unit of group Ⅳ was also significantly higher than that of group Ⅰ in the first two weeks (P<0.01). In the third week, average haugh unit of group Ⅳ was significantly higher than that of the other three groups (P<0.05). In the last two weeks, average contents of DHA in groups Ⅱ-Ⅳ were significantly higher than those of group Ⅰ(P<0.01), whereas group Ⅳ was the highest. To sum up, the effects of DHA compound additive in diets can improve production performance and egg quality. According to the experiment results, the 8% DHA compound additive in diets is found to be the best approach.