Aims: This present study was conducted to evaluate the effect of feeding various levels of paddy with redworms (Perionyx excavates) on growth performance of Go Cong chicken under free range system of rearing.

Experimental design: A total of 250 free range Go Cong chicken from 5 to 14 week of age with five treatments including control treatment consists of 100% self-mixed feed and 3 treatments with paddy and redworm levels 20% (TQ20); 25% (TQ25); 30% (TQ30) respectively; and treatment with 100% paddy (LUA) were included in the study. Place and duration of study: The study was conducted in Thanh My hamlet, Thanh Duc commune, Long Ho district, Vinh Long province. Methodology: All chickens included were cared under uniform managemental conditions. Every morning, cleaning the trough, weighing the leftover food in the trough and feeding the chickens with new food. Food and water was ensured to be enough in the trough. Growth targets: Body weight, body weight gain, average feed consumption and feed conversion ratio (FCR) were collected for growth targets in each experimental period.

Results: At 14 weeks of age, the heaviest weight was found in the control treatment (1299.40g) similar to TQ25; and the lowest one was LUA treatment (966.00g) (P0.05). At 5 to 14 weeks of age stage, the lowest value of FCR was revealed in the control (3.73), similar to TQ25 treatment and was statistically significant different from LUA treatment (5.56)(P

Conclusion: In summary, the feeding treatment containing 25% Perionyx excavatus and 75% paddy revealed the best results and can be suggested to apply for raising free range chicken