If people were serious about this then it would be highly restricted for livestock.
Some years ago I suffering extreme chills for many days. I had to beg doctor for a round. She was mortified that I would want them. Next step was full ER visit while on a business trip out of state. So no insurance.
Was fine after a few days.
This happens every so often. Each time is a nightmare getting a prescription despite history.
You might want to look for bacteriophage treatment, which lacks many downsides (at the cost of needing matching like donor organs, and thus distribution infrastructure).