Biztalk Testing tools

Unit and Functional Testing
Microsoft Visual Studio® Team Suite Testing Tools
Used for unit testing .NET code. For more information about the testing tools that are integrated into Visual Studio 2005 Team System see "Visual Studio 2005 Team System: Enabling Better Software Through Better Testing" at http://go.microsoft.com/fwlink/?LinkId=102208.

BizUnit
A framework designed for automated testing of BizTalk solutions.
Use of this tool is not supported by Microsoft, and Microsoft makes no guarantees about the suitability of this programs. Use of this program is entirely at your own risk.

NUnit
Used for unit testing .NET code.
Use of this tool is not supported by Microsoft, and Microsoft makes no guarantees about the suitability of this programs. Use of this program is entirely at your own risk.
For more information about NUnit, see http://go.microsoft.com/fwlink/?LinkID=47931

Performance Testing
Microsoft BizTalk LoadGen 2007 tool
Load generation tool used to run performance and stress tests against BizTalk Server.
For more information about the Microsoft BizTalk LoadGen 2007 tool, see http://go.microsoft.com/fwlink/?LinkId=59841.