The effects of seaweed Gracilariopsis persica in the diet on performance and and thyroid hormones in laying Japanese quail

The aim of this study was to investigate the effects seaweeds Gracilariopsis persica in diets on performance and TSH، T3 and T4 hormones in serum of laying quail. A total of 112 laying quails were randomly allocated into four dietary treatments (diets containing 0، 1، 3 and 5% seaweed) with 4 replicates of 7 birds each. The birds were fed on experimental diets for 12 weeks. Eggs were collected daily and weighed. Then egg yield (based on hen day)، egg mass، feed conversion ratio and the percent of abnormal eggs were calculated during the 7-10، 11-14، 15-18 and 7-18 weeks of age. At the end of the experiment، the blood samples were taken from two birds per each replicate and analyzed for T3، T4، TSH hormones. There were no significant differences in egg production، feed intake، feed conversion ratio، egg weight، egg mass and percentage of abnormal eggs between treatments. However، the highest egg production was belonged to birds fed 3% of seaweed in diets and had significant difference with birds fed on diets containing 5% seaweed (P<0. 05). There were no significant differences in T3، T4، TSH of serum between treatments. As conclusion، Gracilariopsis persica can be include up to 3% in laying quail diets.