A template-assembly for effecting radiation treatment within an animal body by implanting one or more hollow needles at a desired location within the animal body includes a template frame being mountable to a stepping device of a radiation treatment device. The template frame has a needle guiding component having a plurality of guiding apertures for guiding the one or more hollow implant needles towards the desired location within the animal body. The template-assembly has a needle fixation component for fixating one or more of the implanted needles relative to the animal body, wherein the needle fixation component can be sutured to the skin of the animal body.