You can’t escape reading or hearing about disease-causing microorganisms — with exotic names like MRSA and E. coli OH:157 — that develop resistance to drugs. There are also plenty of reports about resistance to antibiotics in livestock and people or weeds’ resistance to crop chemicals.
There is another kind of resistance in cattle, swine, sheep and goats: internal worms that develop resistance to deworming agents. On this subject, I offer you this true story about a couple of cattlemen and their herd of 200 brood cows out on Cowpath Road.
Source: "Fighting Resistance with Brains and Brawn" Ohio Country Journal, June 24, 2019.