The 51-year-old presenter, who is best-known for co-presenting Countryfile for 10 years between 2004 and 2014, recently revealed she had been diagnosed with breast cancer and would be undergoing a mastectomy.
Bradbury wrote: "Goodbye left boob.Thank you. I've breastfed my children w/you,I've jumped into the sea, I've walked thousands of miles with you. Now it's time for something new.
"Wise is the one who flavours the future with some salt from the past.' Check yourselves #BreastCancerAwarenessMonth."
Bradbury, who is vice-president of the CPRE in South Yorkshire, urged other women to get themselves checked and to seek help if they notice any changes in their body.
She told the Mail on Sunday she was going public with her news because she wants to encourage others to get themselves tested.
And in her post on Twitter, she shared a picture and a moving message.
Her post had thousands of likes within minutes, and a number of replies thanking her for speaking out about her cancer journey, as well as others describing her as inspirational and brave.