100 Years of Progress in Calf Health: Marking a Century Since Pasteurisation Was Proven to Reduce Infectious Disease in Calves

UK research from back in 1926.

This year, 2026,  marks 100 years since the breakthrough research at the National Institute for Research in Dairying (N.I.R.D.), Reading, where S. Bartlett and colleagues demonstrated that  pasteurising whole milk for calves reduces disease.

In 1926, Bartlett ran what is still one of the clearest controlled trials ever done in the UK on feeding calves pasteurized milk :

They used 11 matched pairs of calves — one fed raw milk, the other pasteurized milk.

The results showed that :
-  Calves on pasteurised milk had far fewer tuberculin reactions, proving reduced exposure to disease
- And both groups remained healthy and thrived

Bartlett’s earlier work showed the same pattern:
“75% of calves fed raw milk reacted to tuberculin; 55% of calves fed pasteurised milk reacted.”

Taking into consideration that the calves could have been infected by the airborne route, this was the first evidence that gentle pasteurisation protects calves from infectious risk, especially bovine TB, which was widespread at the time.

Rowett Institute, Aberdeen confirmed it

Independent trials at Aberdeen (Crichton & Biggar) backed up the Reading findings:
- No loss of growth from pasteurisation
- Raw‑milk calves looked slightly better in coat condition
- But pasteurised‑milk calves showed lower disease exposure

Two different research centres gave the same conclusion.

Why it mattered then — and still matters now

By the early 1930s, Reading had refined the method into what we now recognise as low‑temperature pasteurisation, the forerunner of today’s 60 °C / 60‑minute approach.

The principle remains unchanged:

Pasteurise milk gently → kill pathogens → keep the nutrition.

A century later, remarkably same disease challenges and probably more!

The knowledge learned a century ago underpins todays common practices:
- Colostrum pasteurisers
- Waste‑milk pasteurisation
- Johne’s control programmes

-Mycoplasma bovis control
- TB‑risk reduction
- Improved early‑life immunity

As we look back 100 years, the message is simple:

Pasteurisation was a theory — then  it was proven on British farms, by British scientists, for British cattle. Much later researchers in North America looked at it again and commercial systems were created.

Graham Shepherd introduced to the UK, the first  readily available calf milk and colostrum pasteurization systems in 2008 and has spread the technology across the country.

Pasteurisation is still one of the most effective, practical disease‑control tools available tobreeders of dairy cattle and beef cross calves.

Graham Shepherd February 2026

References on request. Milk & Nutrition Part 3, NIRD Shinfield Reading p27 1938