Reengineering Life

Scientists Are Building Cows to Resist Climate Change

Using gene editing to make heat-tolerant cows could result in ‘super calves’

Emily Mullin
Future Human
Published in
5 min readNov 10, 2020
Photo illustration of pipette in background with cows in foreground.
Photo illustration; Image courtesy of AgResearch

Reengineering Life is a series from Future Human about the astonishing ways genetic technology is changing humanity and the world around us.

If we want to survive as the planet gets hotter, the animals we rely on for food will need to adapt to climate change. Some scientists think they can speed up that adaptation using gene editing.

One problem that farmers face is heat stress in dairy cattle, which happens when cows are exposed to high temperatures for too long. Cows that are heat stressed eat less, make less milk, and have a hard time conceiving. In hot temperatures with high humidity, heat stress can even cause death. In the United States, heat stress costs the dairy industry $900 million a year or more, and in the developing world, where small farmers rely on just a few animals for their livelihood, the impact can be devastating. As temperatures rise globally, heat stress is likely to only get worse.

“This is not only markedly reducing milk production but also affects the cows’ well-being and fertility,” Goetz Laible, PhD, an animal scientist at New Zealand’s AgResearch, a government-owned company that conducts research to benefit the country, tells Future Human. “Rising temperatures and predicted longer and more intense periods of warm weather can only mean that the problems with heat stress and fertility will increase.”

Laible and his colleagues recently took a unique approach to addressing this issue: They tried to change the color of cows’ coats using genetic engineering.

Because darker-colored animals absorb more heat from sunlight, they’re thought to be more affected by warmer temperatures than lighter-colored animals. As Laible and his colleagues describe in a paper recently posted to the preprint server bioRxiv, they sought to lighten the coats of Holstein-Friesian cattle — the quintessential dairy cows known for their white coats with patches of black — to make them more resilient to our changing climate.

Using the gene-editing tool CRISPR, the researchers altered a pigmentation gene…



Emily Mullin
Future Human

Former staff writer at Medium, where I covered biotech, genetics, and Covid-19 for OneZero, Future Human, Elemental, and the Coronavirus Blog.