EDITORIAL published: 11 February 2022 doi: 10.3389/fphys.2022.848955 Editorial: Animal Welfare - Volume II: Using Bio-sensing Devices to Assess Farm Animal Welfare Jeroen Brijs 1 , Andreas Fahlman 2,3,4 , Martin Fore 5 and Xavier Manteca 6* 1 Hawai’i Institute of Marine Biology, University of Hawai’i at Manoa, Honolulu, HI, United States, 2 Fundación Oceanografic de la Comunidad Valenciana, Valencia, Spain, 3 Kolmården Wildlife Park, Kolmården, Sweden, 4 Global Diving Research SL, Valencia, Spain, 5 Department of Engineering Cybernetics, Norwegian University of Science and Technology, Trondheim, Norway, 6 School of Veterinary Science, Universitat Autònoma de Barcelona, Barcelona, Spain Keywords: animal welfare, bio-logging, sensors, precision livestock farming, fish, aquaculture, cattle Editorial on the Research Topic Animal Welfare - Volume II: Using Bio-sensing Devices to Assess Farm Animal Welfare Animal welfare has become an essential element of modern animal production. First and foremost, animal welfare is grounded on ethical concerns that derive from the fact that farm animals are sentient beings (i.e., they are able to suffer and experience emotions; Le Neindre et al., 2017). Societal concern over the welfare of farm animals has increased recently and a growing number of consumers in many countries now demand that farm animals are reared, transported, and slaughtered as humanely as possible. Improving animal welfare may have additional benefits. For example, since many welfare problems can detrimentally affect production (via impaired appetite, growth, immune responses and reproduction), improving farm animal welfare can have positive effects on the quantity and quality of the final marketed product (Ashley, 2007). Improving animal welfare is also one of the strategies that may contribute to reducing the use of antimicrobials in Edited and reviewed by: John D. Imig, farm animals (EMA and EFSA, 2017), which will likely benefit human health in the long-term. Medical College of Wisconsin, Developing and validating science-based tools to objectively assess the welfare of farm animals United States is necessary to identify problems and monitor progress when strategies are being implemented to *Correspondence: enhance and assure welfare. Assessment protocols to improve welfare in farm animals are also Xavier Manteca needed for certification schemes, which have become widespread in many countries. Although xavier.manteca@uab.cat several protocols have been developed to assess the welfare of farm animals (e.g., Botreau et al., 2007), these have several limitations. For example, most current methods to assess welfare can Specialty section: identify existing issues but fail to anticipate future welfare problems and hence are not helpful to This article was submitted to implement preventative measures. Also, existing protocols are typically based on focal assessments Physio-logging, and only provide information for short periods of time. However, the welfare status of animals a section of the journal evolves over time as a dynamic interaction between the animal and its environment, and current Frontiers in Physiology assessment protocols do not enable a life-long evaluation of animal welfare. Finally, most of the Received: 05 January 2022 existing welfare assessment tools are intended to monitor welfare at a group level and limited Accepted: 18 January 2022 attention is given to individual animals. Published: 11 February 2022 This Research Topic includes six studies -one on cattle and five on farmed fish- that show the Citation: potential of using biosensors to overcome the limitations of existing animal welfare assessment Brijs J, Fahlman A, Fore M and Manteca X (2022) Editorial: Animal protocols. In the study on cattle welfare, Palacios et al. use implantable bio-loggers to measure the Welfare - Volume II: Using Bio-sensing effect of high grazing density on the circadian rhythms of temperature, heart rate, and activity. This Devices to Assess Farm Animal Research Topic provides an example of how individual, continuous measurements can provide Welfare. Front. Physiol. 13:848955. information on how animals cope with their environment, and the results suggested that a high doi: 10.3389/fphys.2022.848955 stocking density may exacerbate the competition for valuable resources. Frontiers in Physiology | www.frontiersin.org 1 February 2022 | Volume 13 | Article 848955 Brijs et al. Editorial: Biosensors and Farm Animal Welfare Three of the farmed fish studies focused on quantifying of fish welfare. Heart rate was found to be a reliable indicator swimming activity. Arechavala-Lopez et al. placed gilthead in salmon, as it exhibited variations that were clearly linked to seabream (Sparus aurata) in swim tunnels to investigate whether seasonal/diurnal variations and stress-induced elevations during observed swimming performance and body movements could crowding. Gamperl et al. sought to investigate how summer be assessed as a welfare index using transmitters measuring conditions of warm and potentially hypoxic water affected acceleration. While these devices did not capture all aspects of farmed salmon, and used devices that measured heart rate, depth seabream activity, they showed promise as an efficient tool for and activity to cover both physiological and behavioral aspects detecting behavioral changes during production. Georgopoulou of their responses. These biosensing devices proved useful for et al. studied European seabass (Dicentrarchus labrax) in a monitoring the conditions and states of farmed salmon and recirculation aquaculture facility. The movement was recorded revealed that while the data was not significantly impacted by using video footage and computer vision methods to extract long exposure to high temperatures and moderate hypoxia, it measures of swimming speed and direction, as well as surface seems that high temperatures in combination with biotic factors attraction. Their results implied that this method was suitable for may be the most substantial climate-change related challenge in detecting both speed and direction, and that these parameters salmon aquaculture. could be useful in monitoring behavioral states in seabass. In conclusion, this Research Topic provides a snapshot of how Stockwell et al. studied large-scale spatial movements, such as bio-sensing devices are used as research tools for studying farmed distance to the cage center and depth, movement speeds and animals by observing parameters such as position, acceleration, turning angles in Atlantic salmon (Salmo salar) using 3D- and heart rate. The articles therein also imply how devices that tracking. This method seemed suitable for monitoring farmed are commercially available today can be used for individual based fish, and interestingly the main indicators were susceptible to welfare monitoring in animal production, potentially leading to changes due to both environmental events (e.g., changes in future industrial applications. stratification) and cage management practices (e.g., feeding). The other two Research Topics measured heart rate, providing a AUTHOR CONTRIBUTIONS direct physiological focus, and were both conducted with Atlantic salmon in sea-cages. Warren-Myers et al. set out to explore the All authors listed have made a substantial, direct, and intellectual utility of heart rate as a parameter for long-term monitoring contribution to the work and approved it for publication. REFERENCES The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential Ashley, P. J. (2007). Fish welfare: current issues in aquaculture. Appl. Anim. Behav. conflict of interest. Sci. 104, 199–235. doi: 10.1016/j.applanim.2006.09.001 Botreau, R., Veissier, I., Butterworth, A., Bracke, M., and Keeling, L. J. (2007). Publisher’s Note: All claims expressed in this article are solely those of the authors Definition of criteria for overall assessment of animal welfare. Anim. Welfare and do not necessarily represent those of their affiliated organizations, or those of 16, 225–228. the publisher, the editors and the reviewers. Any product that may be evaluated in EMA and EFSA (2017). EMA and EFSA Joint Scientific Opinion on measures this article, or claim that may be made by its manufacturer, is not guaranteed or to reduce the need to use antimicrobial agents in animal husbandry in endorsed by the publisher. the European Union, and the resulting impacts on food safety (RONAFA). Committee for Medicinal Products for Veterinary Use (CVMP); Panel on Biological Hazards (BIOHAZ). EFSA J. 15:e04666. doi: 10.2903/j.efsa.2017.4666 Copyright © 2022 Brijs, Fahlman, Fore and Manteca. This is an open-access article Le Neindre, P., Bernard, E., Boissy, A., Boivin, X., Calandreau, L., Delon, distributed under the terms of the Creative Commons Attribution License (CC BY). N., et al. (2017). Animal consciousness. EFSA Support. Publ. 14:1196E. The use, distribution or reproduction in other forums is permitted, provided the doi: 10.2903/sp.efsa.2017.EN-1196 original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. Conflict of Interest: AF was employed by Fundación Oceanografic de la No use, distribution or reproduction is permitted which does not comply with these Comunidad Valenciana, Kolmården Wildlife Park, and Global Diving Research SL. terms. Frontiers in Physiology | www.frontiersin.org 2 February 2022 | Volume 13 | Article 848955