Positive periodic solutions for neutral delay ratio-dependent predator–prey model with Holling type III functional response

By using a continuation theorem based on coincidence degree theory, some new and interesting sufficient conditions are obtained for the existence of positive periodic solutions for neutral delay ratio-dependent predator–prey model with Holling type III functional responsex′(t)=x(t)[r(t)-a(t)x(t-σ1)-ρx′(t-σ2)]-c(t)x2(t)m2y2(t)+x2(t)y(t),y′(t)=y(t)-d(t)+h(t)x2(t-τ(t))m2y2(t-τ(t))+x2(t-τ(t)).An example is represented to illustrate the feasibility of our main results.