For years, Dr. Brooke Miller vaccinated his cow herd before breeding

Then one year, he accidentally skipped the shots.

What happened next changed his mind forever.

“Up until 2022, we followed standard animal health veterinary recommendations by vaccinating our cow herd each year about 60 days prior to breeding with a modified live virus.”

“We still ended up with a handful of cows each spring when we preg checked that obviously got bred and miscarried after 60 to 90 days.”

“In 2022, a light came on… ”

“Our son-in-law, Joe Mantiply, at that time was pitching for the Arizona Diamondbacks.”

“Needless to say, we watched a lot of baseball and traveled a lot, and a lot of the work didn’t get done at home.”

“One of those jobs that didn’t get done was the pre-breeding vaccination of our cow herd.”

“When we preg checked that following spring, we had only one very old cow that was… not pregnant.”

“Needless to say, we learned our lesson.”

“We no longer vaccinate our cow herd with modified live viruses pre-breeding.”

For years, Dr. Brooke Miller vaccinated his cow herd before breeding.

“The experts” told him it would improve fertility and prevent miscarriages.

Then one year, he accidentally skipped the shots.

What happened next changed his mind forever.

“Up until 2022, we followed… pic.twitter.com/kBwU6PMkMX

— Brownstone Institute (@brownstoneinst)September 18, 2026