Construction of growth models using linear differential equations

The paper is focused on the problem of growth models, which can be derived from linear differential equations. Two cases are investigated - higher than second order equation with constant coefficients and first order equation with time-varying coefficient. It is shown that under certain conditions in the first case it is possible to obtain sigmoidal solution, while in the second case the solution can be a bell-shaped or a sigmoidal . The applicability of proposed model for human and broilers growth is demonstrated from the points of view of approximation and prediction.