Development of a Mesh-type model for Canis familiaris and Monte Carlo simulations of radiation dosimetry parameters

With the widespread application of ionizing radiation in animal diagnostics, therapeutic practices, and environmental sciences, the potential impacts of radiation on ecosystems and non-human species have gradually become a global concern. Dogs serve as important animal models in human disease research, and accurate dosimetric evaluation is essential for assessing radiation effects on specific organs and tissues. To achieve efficient dose calculations while preserving realistic anatomy, mesh-type models integrated with Monte Carlo methods provide a novel solution for complex anatomical configurations. In this study, a high-precision mesh-type model of Canis familiaris was constructed using veterinary imaging data and 3D modeling techniques. Monte Carlo simulations with the Particle and Heavy Ion Transport Code System (PHITS) were performed to calculate absorbed fractions and specific absorbed fractions for monoenergetic photons and electrons in the energy range of 0.01-15 MeV, establishing a dosimetric database for Canis familiaris. Results indicate that self-absorption fractions decrease with increasing energy, while organ mass significantly influences specific absorbed fractions, with the testes exhibiting the highest values and large tissues such as muscle and bone the lowest. This mesh-type model overcomes the limitations of traditional voxel and stylized models in terms of anatomical fidelity and flexibility. Overall, these findings provide reliable radiation dose assessment tools for veterinary medicine and environmental protection and support the advancement of radiation risk assessment frameworks for non-human species.