This is a very open question and answer largely depends on the change you r doing. Following is the list of items you should consider:
- Most of the time for minor changes to existing artifacts such as orchestration code/.net change, pipeline component, map or schema change can be done without importing MSI to BizTalk. In these cases just install MSI and restart host works fine.
- In some cases you can just add a specific resource rather than importing whole MSI. E.g if you are adding a new pipeline, as good as you have separate assembly for pipeline, you can add just pipeline assembly as resource to use new pipeline. Same way you can manage other artifacts. BizTalk also supports side by side deployment of assembly. The key to do this is to have artifacts in separate assemblies
- If any of above doesn’t work then consider full import.
Whatever option of deployment method you choose, you must test the same method in your dev, qa environments and catch any issue before doing it in prod.
Hope this help. There r other link on BizTalk deployment, you can refer to.