All natural and certified organic are two different things.
'All natural' does not have as many/same restrictions as 'certified organic'.
Until some people's calves go to 'market' they could be considered 'all natural' because they have not used implants, fed feeds or minerals containing antibiotics or growth hormones, etc.
Good herd-health management and prevention of as many 'problems' as possible is one way to maintain an 'all natural' or 'organic' herd.
I am no expert on the specific rules regarding organic, but I do believe that certain vaccines, and medical treatments are approved for use in herds that are 'certified organic' or 'all natural'.
Not trying to be a wise-guy here, if you use the search feature at the top of the page, you will find there are many threads related to this topic.
Katherine