Just talk to you vet about your puppies and the method of termination.
How To Abort Puppies In An Unwanted Pregnancy?
You can speak to your vet about the mismate shot and it's risks (pyometra) if it's soon enough or you can speak to them about a spay and termination.
www.bullmastiffsonline.com
www.irvinevetservices.com
www.bullmastiffsonline.com
www.irvinevetservices.com
Go see a vet...althought I think is wrong since I like animals