Background: The physical and hygienic quality of pelleted feed can be affected by various factors including temperature and retention time during the conditioning process.

Objectives: To compare the effects of producing pellets with conventional and super-conditioner methods at various temperatures and retention times on pellet quality in term of microbial and physical parameters, and the recovery rate of phytase.

Methods: 8 broiler diets, including mash feed, conventional pellets (COP), and 6 super-conditioner pellets (SUP), processed at 70°C, 80°C, and 90°C each for 3 and 6 minutes were prepared. Total number of aerobic bacteria and fungi, pellet durability index (PDI), hardness and recovery rate of included phytase were then compared between the treatments.

Result: Compared to the mash feed, the total number of viable bacteria in COP and SUP treatments were decreased as the temperature and retention times were increased. fungal population was significantly lower in the pellet treatments than in mash feed in which SUP treatments had lower fungal number than that of COP. PDI were higher (P≤0.05) in the SUP80 and SUP90 treatments than that of COP and SUP70. Pellet hardness was also higher (P≤0.05) in the SUP90 treatments than other pellet treatments. However, phytase activity in the pelleted feeds significantly decreased as compared with mash feed.

Conclusions: The results indicate that an increase in the conditioner temperature may improve feed quality parameters, in which the conditioner temperature of 80°C is recommended for optimal broiler chicken pellet production when using the super-conditioner method.