How CRISPR is Revolutionizing the Farm Animals of Tomorrow
A new era in animal agriculture where precision gene editing creates healthier, more sustainable livestock while improving animal welfare and food security.
For thousands of years, farmers have shaped the genetic destinies of their animals through selective breeding, patiently pairing parents with desirable traits to produce improved offspring. This ancient practice has given us dairy cows that produce more milk, pigs with meatier builds, and chickens that grow faster. But this process is slow, taking generations to achieve meaningful results, and limited to traits that already exist within a species' gene pool.
Today, a revolutionary technology is set to transform animal agriculture as we know it—genome editing.
Imagine pigs that never get sick from devastating viruses, cattle that can withstand extreme heat, or chickens that can resist bird flu. These aren't scenes from science fiction but real-world applications of CRISPR-based genome editing currently being developed in laboratories worldwide.
The CRISPR-Cas9 system, often described as "molecular scissors," is a gene-editing tool that allows scientists to make precise changes to DNA at specific locations in the genome. Originally discovered as an adaptive immune system in bacteria that protects against invading viruses, researchers have repurposed this biological machinery to edit genes in everything from microbes to mammals 3 5 .
"CRISPR/Cas9 is a gene editing tool that we can think of as molecular scissors. We can take those scissors and guide them to a location in the genome and make a precise cut in the DNA."
Unlike traditional genetic modification, which often involves transferring genes from one species to another, gene editing is a more precise and targeted method that makes small, intentional changes to an organism's existing DNA. The goal typically isn't to add foreign genes but to edit existing ones—to remove disease susceptibility or improve resilience 1 .
Think of it as the difference between using a precision scalpel versus crude surgery—CRISPR offers unprecedented accuracy in genetic manipulation.
Represents a significant improvement over conventional breeding methods that struggle with introducing beneficial traits without undesirable side effects 2 .
One of the most compelling demonstrations of CRISPR's potential in animal agriculture comes from research aimed at combating Porcine Reproductive and Respiratory Syndrome (PRRS), a devastating viral disease that costs the global pork industry more than half a billion dollars annually .
Scientists identified that the PRRS virus enters pig cells by attaching to a specific receptor protein called CD163 on the cell surface 1 . Researchers hypothesized that if they could disable the gene responsible for producing this receptor, pigs would become resistant to PRRS infection since the virus would have no way to enter and infect their cells.
PRRS costs the global pork industry over $500 million annually
Researchers identified the precise gene sequence coding for the CD163 receptor protein in pigs 1 .
Scientists designed specific guide RNA molecules programmed to target the CD163 gene 1 .
The CRISPR-Cas9 components were introduced into pig zygotes using microinjection 2 .
The edited embryos were then transferred into surrogate mother pigs to develop to term 1 .
After birth, the piglets were genetically tested to confirm the successful editing of the CD163 gene 1 .
The experiment produced pigs with a disrupted CD163 gene, making them unable to produce the functional receptor that the PRRS virus requires for infection. When exposed to the virus, these gene-edited pigs remained healthy while conventional pigs developed severe disease symptoms 1 .
| Group | Number of Animals | Infection Rate | Mortality Rate | Clinical Symptoms |
|---|---|---|---|---|
| CD163 Gene-Edited Pigs | 12 | 0% | 0% | None observed |
| Conventional Pigs | 12 | 100% | 33% | Severe respiratory distress, fever |
Table 1: Results of PRRS Virus Challenge in Gene-Edited vs. Conventional Pigs
"The anti-PRRS gene editing is 'a tremendous benefit for the swine industry and has no risk to humans,' according to William Muir, professor emeritus of animal sciences at Purdue University" .
Reduced financial losses, decreased mortality rates, lower veterinary costs
Improved welfare, reduced disease suffering, decreased need for antibiotics
More sustainable pork production, reduced antibiotic use in farming
More efficient resource use, reduced waste from animal mortality
Genome editing research relies on a sophisticated array of biological tools and reagents. The following essential components are central to experiments like the creation of PRRS-resistant pigs:
| Reagent/Tool | Function | Application in PRRS Experiment |
|---|---|---|
| CRISPR-Cas9 System | Engineered nuclease that cuts DNA at specific locations | The "molecular scissors" that disrupted the CD163 gene |
| Guide RNA (gRNA) | RNA molecule that directs Cas9 to target DNA sequence | Designed to match and target the CD163 gene sequence |
| Microinjection Apparatus | Precision equipment for delivering reagents to zygotes | Delivered CRISPR components to pig embryos |
| Zygote Culture Media | Specialized solutions that support embryo development | Maintained pig embryos during and after editing process |
| Genetic Sequencing Tools | Methods to confirm successful gene edits | Verified CD163 gene disruption in edited piglets |
Table 3: Essential Research Reagents for Livestock Genome Editing
Beyond these core components, researchers continue to develop improved gene-editing tools, including:
These newer systems offer lower off-target activity and fewer byproducts than earlier alternatives 2 .
Delivery methods have also evolved significantly:
While disease resistance represents a major application of genome editing in livestock, researchers are exploring numerous other traits that could benefit animals, producers, consumers, and the environment:
Scientists have developed slick-coated cattle with short, shiny hair that makes them better able to withstand heat stress. These cattle were approved by the FDA in 2022, making them the first CRISPR-edited animal approved for human consumption in the United States 1 .
Researchers are using gene editing to eliminate painful procedures like dehorning in cattle by introducing the naturally hornless (polled) trait into dairy breeds. The technology could also eliminate the need for castration in pigs 1 .
Pigs have been edited to eliminate alpha-gal sugars that cause allergic reactions in people with alpha-gal syndrome. These "GalSafe" pigs are close to receiving FDA approval .
The regulatory landscape for gene-edited animals is evolving rapidly. The United States, Brazil, and Argentina have allowed the commercialization of some gene-edited cattle, with Brazil and Argentina determining risk levels based on the presence of transgenes (foreign DNA) 9 .
As of 2025, only a few genetically modified animals have received FDA approval for human consumption in the U.S. The complex regulatory process has slowed innovation, with Muir noting that "the expense and time needed for approval scares off investors, meaning many potentially beneficial products don't make it out of the lab" .
Public perception will also play a critical role in determining how quickly these technologies are adopted. To address consumer concerns, gene-edited meats undergo rigorous scientific review to ensure they are just as safe and nutritious as conventionally raised products 1 .
"I would be very comfortable feeding gene edited pork to grandchildren. And that, to me, would be the most precious consumer that I would know about, and so I'd be very comfortable... We are making pigs healthier and more resistant to disease with improved animal welfare. We are not making frankenpig."
Genome editing in farm animals represents a transformative technology with the potential to address some of the most pressing challenges in our food system. From reducing devastating diseases to improving animal welfare and environmental sustainability, the applications are as diverse as they are impactful.
The technology has progressed from proof-of-concept experiments to commercially approved products in little more than a decade, demonstrating both its effectiveness and its potential to reshape animal agriculture.
As with any powerful technology, genome editing comes with important considerations regarding regulation, ethical application, and public acceptance. The promising research on PRRS-resistant pigs illustrates not just scientific achievement but a framework for how these technologies might be responsibly developed and deployed—with benefits for animals, producers, and consumers alike.
Looking ahead, as research continues and newer, more precise editing tools emerge, we can expect to see animals better equipped to thrive in changing environments, resist emerging diseases, and contribute to a more efficient and sustainable food system.
In the words of the researchers driving this revolution, genome editing is "one of the tools in the toolbox farmers can use to improve their animals to better supply food to a growing human population" 1 . As we stand at the frontier of this new era in animal agriculture, that toolbox is expanding in ways we're only beginning to imagine.