This dissertation aims at examining immunological response(s) to PIV-3 infection using in vitro cell culture systems. Based on previous publications, TtPIV-1 was found to be similar to, but distinct from, both human and bovine PIV-3 isolates. These initial findings were based only upon partial sequences of the F and HN viral genes. In Chapter 2 TtPIV-1 is further characterized on cytokine production, viral growth over time, and full genome sequencing as compared to BPIV-3 and HPIV-3. Chapter 3 is aimed at examining the type III IFN response during TtPIV-1, BPIV-3, and HPIV-3 infection. Because paramyxoviruses are known to affect many stages of the type I IFN pathway, it was hypothesized that host cells could utilize type III IFNs during PIV-3 infection to circumvent the downregulation of type I IFNs. Vero cells were used as a natural tool to examine type III IFN signaling pathways independent of type I IFNs. Finally, Chapter 4 uses phosphoproteomics for the large-scale examination of signaling pathways that are affected early in PIV-3 infections.