Abelian integrals and limit cycles for a class of cubic polynomial vector fields of Lotka–Volterra type with a rational first integral of degree two

In this paper, we study the number of limit cycles which bifurcate from the periodic orbits of cubic polynomial vector fields of Lotka–Volterra type having a rational first integral of degree 2, under polynomial perturbations of degree n. The analysis is carried out by estimating the number of zeros of the corresponding Abelian integrals. Moreover, using Chebyshev criterion  , we show that the sharp upper bound for the number of zeros of the Abelian integrals defined on each period annulus is 3 for n=3n=3. The simultaneous bifurcation and distribution of limit cycles for the system with two period annuli under cubic polynomial perturbations are considered. All configurations (u,v)(u,v) with 0≤u,v≤30≤u,v≤3, u+v≤5u+v≤5 are realizable.