Here's how we recommend handling your mating/joining records in Mobble to keep things simple.
1. Add your bulls or rams into Mobble as their own herd. That way you'll be able to move them around easily keep track of where they've been via the herd or ranch history.
2. At mating/joining, add a Herd Movement to record that you've put your bull/ram in with a herd.
3. If you would like to record further details of joining - you can also add a Herd Action for the herd being mated. You can record any extra details such as ram name/number in the notes.
4. You may want to add related tasks/reminders, such as pre-lamb drenching or calving checks.