With the rapid expansion of aquaculture, welfare of fishes and aquatic invertebrates is important. Several jurisdictions have included these taxa under welfare regulation in recent years.1-3,5 As most of these species are poikilothermic vertebrates and invertebrates, they present unique issues that should be addressed by comercial aquaculture producers and industries providing farmed seafood for the global market. This presentation will review some of these issues, taking into account that regulation of welfare requires use of scientifically validated welfare criteria. Welfare legislation for these taxa should be enacted with strong scientific evidence to avoid generating significant unintended consequences3, particularly considering the provisions of point 3.1.6.8. of part III to Annex II to Regulation (EU) 2018/848 related to animal welfare in the aquaculture sector. EA and others similar are prohibited in the EU. The relevance of these laws is important for developing countries willing to export animals intended for food to the EU, they must now comply with these regulations. A rigorous science-based approach to the welfare of aquatic organisms should be based on verified, validated, and measurable endpoints that minimize the risk of unintended negative impacts for all stakeholders.5 Important decisions about their welfare should be based on scientifically robust evidence.
We discuss the ten reasons outlined by Benjamin et al.3 to orient legislators, decision makers and the scientific community. Maintaining high scientific standards is required in order to protect not only aquatic animal welfare but also global food security and the welfare of humans. We will address ‘eyestalk ablation’ in Penaeus vannamei, and review ‘sentience and pain perception’ in female broodstock submitted to eyestalk ablation, and the challenge associated with the production of P. vannamei using this technique from a welfare perspective. We will address two major issues: (1) maturation of female broodstock and the production practice of eyestalk ablation; disease susceptibility and stress-immunity mechanisms, and environmental and biological conditions during grow-out: health-stress-disease axis in ponds, and (2) welfare indicators in decapod crustaceans; the current state on physiological biomarkers; and Operational Welfare Indicators (OWIs): individual and group based, direct and indirect and invasive vs. non-invasive.
The research in shrimp hatcheries from Honduras and Thailand led by Zacarias et al.4 from the University of Stirling will be discussed. Researchers prove that eyestalk ablation is unnecessary because it increases vulnerability to disease. However, we should avoid using feeds prepared with glyphosate-based-herbicides (GBHs)-produced soybeans, these may lead to development of antimicrobial resistance in the offspring and food safety issues.6 We suggest that retailers should increase shrimp welfare demands from producers, which may require cooperation across the supply chain. The practice of eyestalk ablation should be avoided to meet increasing consumer demands for traceability, sustainability, and animal welfare in the shrimp-farming industry.
References
1 Pedrazzani et al. 2024. Insights into Decapod Sentience: Applying the General Welfare Index (GWI) for whiteleg Shrimp (Penaeus vannamei—Boone, 1931) reared in aquaculture grow-out ponds. Fishes 9,440. https://doi.org/ 10.3390/fishes9110440.
2 Crump et al. 2022. Sentience in decapod crustaceans: A general framework and review of the evidence. Animal Sentience7(32) DOI: 10.51291/2377-7478.1691.
3 Benjamin et al. 2024. Reasons to be skeptical about sentience and pain in fishes and aquatic invertebrates, Reviews in Fisheries Science & Aquaculture, 32:1, 127-150.
4 https://www.eurogroupforanimals.org/news/new-research-proves-eyestalk-ablation-unnecessary-and-increases-vulnerability-disease.
5 Urdes et al. 2024. How One Health and One Welfare can strengthen the evidence of a management procedure - A case study of eyestalk ablation in farmed shrimp. Scientific Papers. Series D. Animal Science. Vol. LXVII, No. 1, 2024 ISSN 2285-5750; ISSN CD-ROM 2285-5769; ISSN Online 2393-2260; ISSN-L 2285-5750.
6 Rodulfo et al. 2024. A transposable element–epigenetics One Health perspective to understand Antimicrobial Resistance (AMR) and contamination by Endocrine Disrupting Chemicals (glyphosate, metals), microplastics, Bis(2-ethylhexyl) phthalate (DEPH), and Per- and Poly-fluoroalkyl substances (PFAS) - and adaptation to climate change. Proceedings of Aquaculture 2025 meeting held in New Orleans, LA, USA, March 6-10, 2025, abstract #1107.