The laboratory analysis of the particle size was measured at College of Animal Science and Technologyof Yangzhou University. The test diets particle size analyses were carried out using a Mastersizer 2000 LASER diffractionparticle size analyser (Malvern Instruments Ltd., Malvern, Worcestershire, UK) as described by Hetland et al. (2002), withScirocco 2000G accessory used for dry (feed) sample