Is gene editing an acceptable alternative to castration in pigs?

Abstract

Male piglets are commonly castrated to eliminate the risk of boar taint. Surgical castration is the commonly used procedure and is known to induce pain. Gene modification targeted at eliminating boar taint in male pigs has been proposed as a possible alternative to surgical castration. The aims of this study were to explore public acceptability of this biotechnology using a mixed methods approach. Quantitative data to assess acceptability of 570 participants from southern Brazil were analysed with multinomial logistic regression models and Spearman correlations; qualitative responses of the reasons provided in support of their position were coded into themes. Just over half of the participants (56%) considered gene modification of male pigs acceptable. Acceptability was lower among participants who grew up in an agricultural environment (ρ = 0.02), but was not influenced by sex, age, religion, urban or rural living, or level of education. Acceptability of gene modification of male pigs as an alternative to surgical castration was positively related to the perception of benefits (r = -0.56, ρ<0.0001) and negatively related to the participant’s perception of risks (r = -0.35, ρ<0.0001). Acceptability was not related to knowledge of basic concepts of genetic biotechnologies (r = 0.06, ρ<0.14), or to awareness of issues related to pig castration or boar taint (r = 0.03, ρ<0.44), both of which were low among participants. Participants that considered gene modification of pigs acceptable justified their position using arguments that it improved animal welfare. In contrast, those that were not in favour were generally opposed to genetic modification. Unforeseen downstream consequences of using genetic modification in this manner was a major concern raised by over 80% of participants. Our findings suggest that perceived animal welfare may encourage public support of gene editing of food animals. However, potential risks of the technology need to be addressed and conveyed to the public, as many participants requested clarification of such risks as a condition for support.

CRISPR in livestock: From editing to printing

“…This example represents a potential approach for reducing physical dehorning in dairy cattle without loss of productivity. As mentioned, the use of CRISPR to produce germline ablated male pigs has been proposed [50], and even thought this remains to be proven, it would offer new opportunities to finish with surgical castration in pigs [60,61]. Avoiding these practices in animal husbandry may encourage public support of genome-edited animals for food chain production.…”

On the Road to End Pig Pain: Knowledge and Attitudes of Brazilian Citizens Regarding Castration

“…Although some studies indicated that consumers in Europe have positive attitudes towards immunocastration [ 31 , 32 , 56 ], a widely reported limitation for adoption of this method is producers’ and industry stakeholders’ concern regarding consumer acceptance [ 17 , 20 , 23 , 48 ]. Indeed, health and safety aspects are the animal production traits that consumers in different parts of the world perceive as most important when assessing alternatives to pig castration [ 30 , 33 , 48 , 57 ].…”

“…In order to maintain its’ social license, the livestock industry must regard the values of citizens and consumers. Although citizens in general are unaware of the husbandry practices and technologies used in animal production, when asked about surgical castration of pigs without anesthesia, most classify these practices as detrimental to animal welfare [ 30 , 31 , 32 , 33 ]. Housing and management practices that are highly prevalent in intensive pig farming such as confinement, feeding practices that leave animals hungry for most of the day, and painful mutilations have become highly contentious [ 34 , 35 ].…”

“…Although surgical castration without pain control is widely used in Brazil, a growing proportion of the farmers are moving to immunocastration [ 39 ], with support from large retailers and industry stakeholders (see [ 37 , 40 ]). One study showed that Brazilian citizens had low awareness about pig castration but, when informed about it, expressed negative attitudes due to the pain it causes to the animals [ 33 ]. However, there is no information about the opinion of the public regarding the acceptability of immunocastration or raising entire males.…”

Livestock breeding for the 21st century: the promise of the editing revolution

“…Reports of surveys of public opinion are starting to emerge [52][53][54] . These show general support for application of the technology, with a parallel cry for more information so that informed opinions can be developed [55] . Recognized as a topic of public interest, the Nuffield Council on Bioethics (UK) is currently preparing a report on 'Genome Editing and Farmed Animals' which will provide a yardstick on the ethical aspect of this technology in livestock.…”