Though researchers are turning to gene editing to address animal welfare issues, it appears that activists remain lukewarm to that use of the technology.
Hornless dairy cows, disease-resistant swine and poultry, male pigs that never reach puberty and cattle that can better tolerate heat are some of the projects now in the works to reduce suffering among livestock.
Animal welfare groups, however, are treading carefully and appear hesitant to embrace precision breeding, even when it’s intended to spare livestock from painful procedures. This raises the question of whether they’ll ever endorse research aimed at improving conditions for livestock under the current methods of agricultural production.
Indeed, some organizations, such as Eurogroup for Animals, an umbrella group representing animal welfare organizations across Europe, have a sharply different objective than simply improving quality of life. “In actual fact, we firmly believe that industrial intensive animal agriculture is unsustainable and that we need to move towards alternative production and management systems that are more respectful of animal sentience and of the environment,” Elena Nalon, the group’s senior veterinary advisers for farm animals, said via a written statement to the Alliance for Science.
The issue was highlighted recently when the US biotech firm Recombinetics and Dutch company Hendrix Genetics announced the birth of multiple healthy litters of precision-bred male piglets that will remain in a pre-pubescent state, thus eliminating the need for castration. Company officials hailed the new method as both a breakthrough for animal welfare and a potential boon for the pork industry.
The castration of male piglets, whether performed surgically or through chemical injections, is common practice throughout the West. Nearly all male piglets raised in the United States are castrated and pig farmers in all but a small handful of European countries also castrate their male stock.
This is done to avoid what is known as boar taint, a foul odor that can arise from cooking the meat of fully intact male pigs. Although the prevalence of boar taint is only estimated to be around five percent, nearly all large-scale pig farming operations castrate all of their male piglets before they are weaned, most often within the first three to five days of life. In the US, the vast majority of castrations are performed without anesthesia, while efforts to require the use of anesthesia in the EU have stalled out, leaving only a few European countries with laws on the books prohibiting castration without the use of pain relief.
“This first litter of permanently pre-pubescent piglets is a huge success. Not only does the industry benefit, but once this technology is deployed commercially, we can eliminate an animal welfare issue, while maintaining a quality product for consumers,” Sally Rockey, the executive director of the Foundation for Food and Agriculture Research (FFAR), which awarded a $500,000 grant to fund the Recombinetics research, said in a statement.
Tad Sonstegard, who led the research as the chief executive and scientific officer of Acceligen, Recombinetics’ agriculture division, also pointed to the animal welfare benefits.
“The birth of these castration-free prototype piglets using commercially relevant genetics is just another example of how Acceligen is working to deploy our breeding technologies to help producers better meet the demands of consumers and producers to improve food animal well-being,” he said.
Animal welfare groups not yet on board
In a statement provided to the Alliance for Science, a spokesman for the Humane Society of the United States indicated that the organization had not yet officially adopted a stance on castration-free swine.
“This is a significant, emerging issue we are researching deeply from all angles to ensure we’re aware of all potential ramifications,” Josh Balk, who heads the Humane Society’s farm animal protection team, said.
Eurogroup for Animals called the use of gene editing technology on pigs “a delicate issue.” The group stressed that the use of CRISPR technology is not currently allowed in the EU so any animals produced “with such methodology would not be authorized for human consumption unless a legislative change occurs.” Eurogroup for Animals also expressed concerns about overall research into gene editing techniques.
“We fear that using genetic manipulation techniques to prevent puberty in pigs is a palliative solution, allowing the pig sector to continue to operate under industrial intensive confinement conditions,” Nalon said in her statement to the Alliance.
Nalon and her colleagues said that rather than raising male piglets that have been bred to not reach sexual maturity, European pork producers should instead either keep the boars whole or administer vaccines to induce a “temporary and reversible suppression of puberty.”
Jaydee Hanson, policy director for the Washington, D.C.-based Center for Food Safety, which unsuccessfully litigated to stop the introduction of a genetically modified fast-growing salmon in the US, also expressed a certain degree of skepticism toward the use of precision breeding to create castration-free pigs.
“Castration is not fun for the pig or the people doing it, so I understand the interest behind this,” he told the Alliance for Science.
Hanson said that because puberty cannot be blocked in male piglets through traditional techniques, he thought this was “a more logical use of this technology” than using precision breeding to create hornless cows.
It’s unclear where consumers stand. Though a 2018 Pew survey found that Americans support genetic engineering in animals to benefit human health, they were not queried about its use for animal welfare.
When will these piggies go to market?
For the foreseeable future, the positions of activists are largely just hypothetical. In the US, the Federal Drug Administration oversees genetically engineered animals and has thus far only approved one GM food animal, Aquabounty‘s fast-growing transgenic salmon, after a multi-year process.
While genetics companies like Recombinetics are hopeful that a recent executive order issued by President Trump will streamline the review and approval process for agricultural biotechnology, Sonstegard said the current conditions in the US likely mean that it will be a long time before castration-free pigs become a viable option for the nation’s pork producers.
“Small companies like ours and academic institutions will have difficulty commercializing precision-bred products that stand to benefit consumers, the planet and the animals,” Sonstegard said.
Some creators of gene-edited animals are looking to avoid the US regulatory process altogether by taking their products to other countries, according to a report in Nature.
In the EU, the use of precision breeding techniques on animals was not directly addressed in the 2018 European Court of Justice ruling that calls for subjecting precision breeding techniques like genome editing to the same regulatory scheme that governs transgenic organisms (GMOs). That ruling has been criticized by the European Union’s own top science panel, the US Department of Agriculture, seed breeders in the Netherlands, 13 nations that signed on to a joint position paper, and scientists representing 93 European plant and life sciences research centers.
Although the uncertainty surrounding the ECJ ruling leaves new animal breeding techniques “in limbo” and is likely to drag on for years, Sonstegard said, there is still hope that the precision breeding technique developed by Recombinetics will eventually reach Europe.