An ecoepidemiological model with disease in predator: the ratio-dependent case

We propose a ratio-dependent demographic predator-prey model in which also a disease spreads among predators via homogeneous mixing. Equilibria of the system are analysed, numerical evidence shows limit cycles to arise. The disease effects on the model are discussed. Comparisons of these findings with results of some related investigations allow the general conclusion that an infection in either species, prey or predator, may act as a biological control.