Pakistan Journal of Nutrition1680-51941994-7984orgz10.3923/pjn.2019.101.108SobriM.WiryawanK.G.KartiP.D.M.H.WibawanW.T.22019182Background and Objective: This study was conducted to analyze the effect of the neutral detergent fiber (NDF) and fiber particle size on mortality, hematology, stress status, immunity and number of E. coli in New Zealand white (NZW) crossbred rabbits during the postweaning period. Methodology: A total of 144 NZW crossbred rabbits were used in the study. The trial design was a completely randomized 3×3 factorial pattern, namely, 3 levels of the concentration of neutral detergent fiber (NDF) (F1, F2 and F3) and 3 sizes of fiber particles (P1, P2 and P3). Each treatment was repeated 4 times and each replication consisted of 4 trials. Results: The average mortality up to 12 weeks was 19.44%. The treatment combinations of F3P2 and F2P2 had the lowest mortality rate (0%) and low rates of E. coli infection at 2.55 and 2.71×10^{9} CFU mL^{–}^{1}, respectively. The feed treatment affected the hematological values in rabbits during the postweaning period. The results indicated that there was a relationship between mortality and E. coli infection. Moreover, the F3P2 treatment was the best feed combination observed in this study. Conclusion: The feed treatment affected the mortality, immunity, hematology and stress status of NZW crossbred rabbits during the postweaning period.]]>Lebas, F. and L. Fortun-Lamothe,1996Raharjo, Y.C., P.R. Cheeke and N.M. Patton,1990Gidenne, T., N. Jehl, A. Lapanouse and M. Segura,2004Nicodemus, N., L. Perez-Alba, R. Carabano, C. de Blas, I. Badiola and A.J.G.P. de Rozas,2004Bennegadi, N., G. Fonty, L. Millet, T. Gidenne and D. Licois,2003Gidenne, T. and D. Licois,2005Escherichia coli.]]>Van Soest, P.J., J.B. Robertson and B.A. Lewis,1991Maertens, L.,1994Cooke, B.D., A.J. Robinson, J.C. Marchant, A. Nardin and L. Capucci,2000Bortolotti, A., D. Castelli and M. Bonati,1989Oryctolagus cuniculus).]]>Carabano, R., M.J. Villamide, J. Garcia, N. Nicodemus and A. Llorente,2009De Blas, C. and J. Wiseman,2010AOAC.,2005Stott, G.H.,1981Lanning, D., P. Sethupathi, K.J. Rhee, S.K. Zhai and K.L. Knight,2000Yun, C.H., H.S. Lillehoj, J. Zhu and W.G. Min,2000Eimeria maxima.]]>Nurliyani, M. Julia, E. Harmayani and E. Baliarti,2013Steel, R.G.D. and J.H. Torrie,1980Moore, D.M.,2006Gutierrez, I., A. Espinosa, J. Garcia, R. Carabano and J.C. de Blas,2002Ensminger, M.E., J.E. Oldfield and W.W. Heinemann,1990Dellman, H.D. and E.M. Brown,1992Kresno, S.B.,2001Tizard, I.,2013Guyton, A.C. and J.E. Hall,2012