Effects of feed supplement with terminalia catappa extract on growth performance and innate immunity of striped catfish (Pangasianodon hypophthalmus)

Abstract

The study was conducted to determine the effective method for supplementation of Terminalia catappa extract in feed on the growth performance and innate immunity of striped catfish (Pangasianodon hypophthalmus). The experiment was designed with three treatments, mixed pellet with 1% T. catappa extract (T1), top coating with 1% T. catappa extract (T2), and control treatment. Experimental fish were sampled at day 30th of feeding experiment for growth parameters, immune parameters and challenge experiment. Results showed that: (i) there was no difference in growth performance anmong the three treatments; (ii) two supplemented treatments were enhanced immune index, disease resistance against Edwardsiella ictaluri compared to control treatment. In particular, the erythrocytes, leukocytes, monocytes, lymphocytes and lysozyme activity of fish were significantly increased in the supplemented treatments higher than the control treatment (P <0.05). After being challenged to E. ictaluri, the cumulative mortality of fish in the supplemented treatments were lower than that of the control treatment. In which, fish fed mixed pellet with 1% T. catappa extract (T1) had the lowest mortality (55.56 %). In summary, mixed pellet with 1% T. catappa extract was performed better than top coating pellet 1% T. catappa extract in the enhancement of immune parameters and disease resistance against E. ictaluri of striped catfish.