Anyone ever see a Moocall calving sensor used?   I'm not interested in getting one but curious if they actually work.  Looks like they are made in the UK.  Here's a link on them.  Good video in the link about how it works.   It's just something I've never heard of before, neat idea but seems like more work than necessary.   Our cows calve just fine on their own.    Cost is $299.   https://www.moocall.com/how-it-works/#learnmore