  An N-dimensional generalization of Nicholson's equation is analyzed. We
consider a model including multiple delays, nonlinear coefficients and a
nonlinear harvesting term. Inspired by previous results in this subject, we
obtain sufficient conditions to guarantee strong and uniform persistence.
Furthermore, under extra suitable hypotheses we prove the existence of
T-periodic solutions and, reversing the prior conditions in a convenient
manner, we show that the zero is a global attractor.
