diff --git a/polymorphic/tests/__init__.py b/polymorphic/tests/__init__.py
index b16a917..32e1838 100644
--- a/polymorphic/tests/__init__.py
+++ b/polymorphic/tests/__init__.py
@@ -400,6 +400,23 @@ class DateModel(PolymorphicModel):
     date = models.DateTimeField()
 
 
+# Define abstract and swappable (being swapped for SwappedModel) models
+# To test manager validation (should be skipped for such models)
+class AbstractModel(PolymorphicModel):
+    class Meta:
+        abstract = True
+
+
+class SwappableModel(AbstractModel):
+    class Meta:
+        swappable = 'POLYMORPHIC_TEST_SWAPPABLE'
+
+
+class SwappedModel(AbstractModel):
+    pass
+
+
+
 # Import tests
 from .test_admin import *
 from .test_orm import *
diff --git a/runtests.py b/runtests.py
index 0e76c03..f0a1609 100755
--- a/runtests.py
+++ b/runtests.py
@@ -57,7 +57,8 @@ if not settings.configured:
                     ),
                 },
             },
-        ]
+        ],
+        POLYMORPHIC_TEST_SWAPPABLE='polymorphic.swappedmodel',
     )