diff --git a/src/core/components/parameter-row.jsx b/src/core/components/parameter-row.jsx
index b44f10041419abaa4e7a738809be1a2dc2d528e0..66c2d1ce7142918e49f81c55000e05f8bdeb8e17 100644
--- a/src/core/components/parameter-row.jsx
+++ b/src/core/components/parameter-row.jsx
@@ -119,17 +119,26 @@ export default class ParameterRow extends Component {
       //// Find an initial value
 
       if (specSelectors.isSwagger2()) {
-        initialValue = paramWithMeta.get("x-example")
-          || paramWithMeta.getIn(["schema", "example"])
-          || (schema && schema.getIn(["default"]))
+        initialValue =
+          paramWithMeta.get("x-example") !== undefined
+          ? paramWithMeta.get("x-example")
+          : paramWithMeta.getIn(["schema", "example"]) !== undefined
+          ? paramWithMeta.getIn(["schema", "example"])
+          : (schema && schema.getIn(["default"]))
       } else if (specSelectors.isOAS3()) {
         const currentExampleKey = oas3Selectors.activeExamplesMember(...pathMethod, "parameters", this.getParamKey())
-        initialValue = paramWithMeta.getIn(["examples", currentExampleKey, "value"])
-          || paramWithMeta.getIn(["content", parameterMediaType, "example"])
-          || paramWithMeta.get("example")
-          || (schema && schema.get("example"))
-          || (schema && schema.get("default"))
-          || paramWithMeta.get("default") // ensures support for `parameterMacro`
+        initialValue = 
+          paramWithMeta.getIn(["examples", currentExampleKey, "value"]) !== undefined
+          ? paramWithMeta.getIn(["examples", currentExampleKey, "value"])
+          : paramWithMeta.getIn(["content", parameterMediaType, "example"]) !== undefined
+          ? paramWithMeta.getIn(["content", parameterMediaType, "example"])
+          : paramWithMeta.get("example") !== undefined
+          ? paramWithMeta.get("example")
+          : (schema && schema.get("example")) !== undefined
+          ? (schema && schema.get("example"))
+          : (schema && schema.get("default")) !== undefined
+          ? (schema && schema.get("default"))
+          : paramWithMeta.get("default") // ensures support for `parameterMacro`
       }
 
       //// Process the initial value
diff --git a/test/unit/components/parameter-row.jsx b/test/unit/components/parameter-row.jsx
index 7c44cfe9a559c51da1cdbd3526f9f31f030668a3..821b457b66a67735464ac357662284dd497f25a1 100644
--- a/test/unit/components/parameter-row.jsx
+++ b/test/unit/components/parameter-row.jsx
@@ -1,5 +1,5 @@
 import React from "react"
-import { fromJS } from "immutable"
+import { List, fromJS } from "immutable"
 import { render } from "enzyme"
 import ParameterRow from "components/parameter-row"
 
@@ -84,3 +84,142 @@ describe("<ParameterRow/>", () => {
     expect(wrapper.find(".parameter__type").text()).toEqual("string")
   })
 })
+
+describe("bug #5573: zero default and example values", function () {
+  it("should apply a Swagger 2.0 default value of zero", function () {
+    const paramValue = fromJS({
+      description: "a pet",
+      type: "integer",
+      default: 0
+    })
+
+    let props = {
+      getComponent: () => "div",
+      specSelectors: {
+        security() { },
+        parameterWithMetaByIdentity() { return paramValue },
+        isOAS3() { return false },
+        isSwagger2() { return true }
+      },
+      fn: {},
+      operation: { get: () => { } },
+      onChange: jest.fn(),
+      param: paramValue,
+      rawParam: paramValue,
+      onChangeConsumes: () => { },
+      pathMethod: [],
+      getConfigs: () => { return {} },
+      specPath: List([])
+    }
+
+    render(<ParameterRow {...props} />)
+
+    expect(props.onChange).toHaveBeenCalled()
+    expect(props.onChange).toHaveBeenCalledWith(paramValue, "0", false)
+  })
+  it("should apply a Swagger 2.0 example value of zero", function () {
+    const paramValue = fromJS({
+      description: "a pet",
+      type: "integer",
+      schema: {
+        example: 0
+      }
+    })
+
+    let props = {
+      getComponent: () => "div",
+      specSelectors: {
+        security() { },
+        parameterWithMetaByIdentity() { return paramValue },
+        isOAS3() { return false },
+        isSwagger2() { return true }
+      },
+      fn: {},
+      operation: { get: () => { } },
+      onChange: jest.fn(),
+      param: paramValue,
+      rawParam: paramValue,
+      onChangeConsumes: () => { },
+      pathMethod: [],
+      getConfigs: () => { return {} },
+      specPath: List([])
+    }
+
+    render(<ParameterRow {...props} />)
+
+    expect(props.onChange).toHaveBeenCalled()
+    expect(props.onChange).toHaveBeenCalledWith(paramValue, "0", false)
+  })
+  it("should apply an OpenAPI 3.0 default value of zero", function () {
+    const paramValue = fromJS({
+      description: "a pet",
+      schema: {
+        type: "integer",
+        default: 0
+      }
+    })
+
+    let props = {
+      getComponent: () => "div",
+      specSelectors: {
+        security() { },
+        parameterWithMetaByIdentity() { return paramValue },
+        isOAS3() { return true },
+        isSwagger2() { return false }
+      },
+      oas3Selectors: {
+        activeExamplesMember: () => null
+      },
+      fn: {},
+      operation: { get: () => { } },
+      onChange: jest.fn(),
+      param: paramValue,
+      rawParam: paramValue,
+      onChangeConsumes: () => { },
+      pathMethod: [],
+      getConfigs: () => { return {} },
+      specPath: List([])
+    }
+
+    render(<ParameterRow {...props} />)
+
+    expect(props.onChange).toHaveBeenCalled()
+    expect(props.onChange).toHaveBeenCalledWith(paramValue, "0", false)
+  })
+  it("should apply an OpenAPI 3.0 example value of zero", function () {
+    const paramValue = fromJS({
+      description: "a pet",
+      schema: {
+        type: "integer",
+        example: 0
+      }
+    })
+
+    let props = {
+      getComponent: () => "div",
+      specSelectors: {
+        security() { },
+        parameterWithMetaByIdentity() { return paramValue },
+        isOAS3() { return true },
+        isSwagger2() { return false }
+      },
+      oas3Selectors: {
+        activeExamplesMember: () => null
+      },
+      fn: {},
+      operation: { get: () => { } },
+      onChange: jest.fn(),
+      param: paramValue,
+      rawParam: paramValue,
+      onChangeConsumes: () => { },
+      pathMethod: [],
+      getConfigs: () => { return {} },
+      specPath: List([])
+    }
+
+    render(<ParameterRow {...props} />)
+
+    expect(props.onChange).toHaveBeenCalled()
+    expect(props.onChange).toHaveBeenCalledWith(paramValue, "0", false)
+  })
+})