In small animal Single Photon Emission Computed Tomography (SPECT), attenuation and scatter introduce important artifacts in the reconstructed images, which could lead to misdiagnosis for subject's follow-up. Gold standard Monte Carlo Simulation (MCS) is one of the well-established tools that has been used in SPECT image reconstruction due to its ability to accurately model photon transport. However, MCS requires extensive computation time to obtain a low noise system matrix and are therefore inappropriate for the rate of daily exams performed in both clinical and preclinical routine: an improvement in simulation speed is thus mandatory. In this work, we validated, compared to a state of the art approach and by using a modified NU-4 IQ phantom, our efficient and simplified modeling of the physical phenomena occurring in the subject. Our approach based on a system matrix decomposition, associated to a scatter pre-calculated database method, demonstrated an acceptable time on a standard computer for daily imaging small animal follow-up (around 1h), leading to a personalized image reconstruction. The reconstruction workflow leads to significant image artifacts reduction as well as a 13% (on average) improvement in terms of recovery coefficients. Results presented in this study, conduct to the validation of the developed approach in comparison with a state of the art one which appears to be far too long for a daily exam perspective.