Role of delay in a predator-prey model with prey infected through external source and contact of the species

  • Krishna Pada Das
  • Rikhiya Dhar
  • Sanjay Sen
  • J. Chattopadhyay


Das et al. (Biosystems, 95, 188-199, 2009) proposed and analyzed an eco-epidemiological model where the prey population was not only infected through contact but also got infection from external sources. Time delay effect is an important component in every biological systems and can
not be ignored. The present paper modifies our previous investigation to observe the quantitative and qualitative behavior of the system with gestation delay. It is observed that for a lower infection rate, the system is stable for all delays; but for a higher infection rate, there exists several critical values of delay factor below and above which system is stable and unstable alternatively. It is also observed
that delay prevents the extinction of predator population and outbreak of disease. Finally we observe that the instability arising from the gestation delay may be controlled if somehow the growth rate of predator population and external source of infection increase and predation rate for infected prey