I have returned to work with my six month old h...

I have returned to work with my six month old happily taking expressed milk. Some days work is very busy and I can't express as much milk as I need. A friend has suggested goats milk as an alternative top up feed to keep frozen as a back up. Has anyone any experience with this ? I'm not a fan of formula unless I need to. Little cherub is a bit eczema prone so trying to limit as many irritants as possible. Any thoughts?????