Naturally occurring compounds that can reduce methane production in anaerobic conditions have been studied for quite some time as feasible approaches to mitigate methane production in ruminant animals, especially those of commercial importance. Asparagopsis taxiformis (red algae) and Dictyota bartayresii (brown algae) are effective inhibitors of methane synthesis under in vitro anaerobic fermentation systems (Machado et al., 2014) likely because of their high concentration of secondary metabolites that are toxic to the typical rumen microbiota, including protozoa. In addition to phytoplankton (Palmer and Reason, 2009), Asparagopsis contains a high concentration of haloform compounds (e.g., bromoform, chloroform) while Dictyota has a high concentration of isoprenoid terpenes. Despite the economic and biological impact of diverse phytochemicals on reducing methane production in ruminant animals (Tedeschi et al., 2021), haloform compounds’ environmental impact and safety, in particular, are still unclear. In the present study, Munõz-Tamayo and collaborators (2021) listed relevant literature about the impact of A. taxiformis on ruminal methane production.

Concurrent to the understanding of mechanisms and biology behind the reduction of ruminal methane, mathematical models can lead the way to enhance the effectiveness of feeding A. taxiformis under commercial applications. Thus, in the present study, Munõz-Tamayo and collaborators (2021) sought to develop a mathematical model to understand the rumen fermentation changes in vitro experimentation containing extract of A. taxiformis by adapting a previously documented model by Muñoz-Tamayo et al. (2016).

Modeling development, calibration, and evaluation steps should be independent of each other, requiring complete, distinct, and separate databases (Tedeschi, 2006). However, in rare circumstances where such requirements cannot be met because data availability is scarce, the cross-validation technique, when possible, should be considered to assess data dispersion’s effects on model adequacy. In other situations, clear reasoning for failing to do so must be addressed in the paper. In the present paper, Munõz-Tamayo and collaborators (2021) explained the limitations in their modeling efforts were primarily due to the lack of ideal data: “experiments with simultaneous dynamic data of bromoform, volatile fatty acids, hydrogen, and methane.” Regardless of the availability of ideal data, improvements in the conceptual model are warranted to include amino acids and branched-chain fatty acids fermentation dynamics in the rumen and the fluctuations in ruminal pH.

References

Machado L, Magnusson M, Paul NA, Nys R de, Tomkins N (2014) Effects of Marine and Freshwater Macroalgae on In Vitro Total Gas and Methane Production. PLOS ONE, 9, e85289. https://doi.org/10.1371/journal.pone.0085289

Muñoz-Tamayo R, Chagas JC, Ramin M, Krizsan SJ (2021) Modelling the impact of the macroalgae Asparagopsis taxiformis on rumen microbial fermentation and methane production. bioRxiv, 2020.11.09.374330, ver. 4 peer-reviewed and recommended by PCI Animal Science. https://doi.org/10.1101/2020.11.09.374330

Muñoz-Tamayo R, Giger-Reverdin S, Sauvant D (2016) Mechanistic modelling of in vitro fermentation and methane production by rumen microbiota. Animal Feed Science and Technology, 220, 1–21. https://doi.org/10.1016/j.anifeedsci.2016.07.005

Palmer CJ, Reason CJ (2009) Relationships of surface bromoform concentrations with mixed layer depth and salinity in the tropical oceans. Global Biogeochemical Cycles, 23. https://doi.org/10.1029/2008GB003338

Tedeschi LO (2006) Assessment of the adequacy of mathematical models. Agricultural Systems, 89, 225–247. https://doi.org/10.1016/j.agsy.2005.11.004

Tedeschi LO, Muir JP, Naumann HD, Norris AB, Ramírez-Restrepo CA, Mertens-Talcott SU (2021) Nutritional Aspects of Ecologically Relevant Phytochemicals in Ruminant Production. Frontiers in Veterinary Science, 8. https://doi.org/10.3389/fvets.2021.628445

The predominant form of agriculture in sub-Saharan Africa is mixed crop and livestock production, typically in extensive systems characterised by low productivity and little input (Tui et al., 2021). Such extensive systems experience many challenges, including access to rangeland and other sources of livestock feed, loss of soil quality, increasingly unpredictable climate but also operational constraints such as access to markets and veterinary care.

The work by Gobvu and collaborators (2025) addresses livestock farming sustainability specifically in the context of a Transfrontier Conservation Area (TFCA). A TFCA is defined as part of an ecological region reaching across boundaries of two or more countries and in which there are protected areas as well as resource use areas. TFCAs are founded to facilitate collective management of resources for the benefit of biodiversity as well as socio-economic development (SADC, 2025).

Livestock farming in TFCAs face additional challenges arising from the tension between biodiversity protection and resource use, such as wildlife predation on livestock, competition between livestock and wildlife for feed and water as well as spread of infections between livestock and wild animals (Matseketsa et al., 2019; Caron et al., 2013; Cumming, 2011).

The paper reports a study that was part of a larger project (EU-ProSuLi project, Caron et al.,  2022) aiming at promoting local development and well-being of residents in the Great Limpopo TFCA, with focus on the Sengwe Communal Area in Zimbabwe. The specific aim was to test a methodology for identifying interventions that are aligned with the needs of the local stakeholders (demand-driven interventions. Anticipatory scenario building in the context of workshops was used in combination with individual questionnaires.

Community representatives (n=31) were purposefully selected for their expected ability to act as knowledge brokers. A team of 10 facilitators supported the discussion through plenary and group work sessions. The participants were asked to identify factors of change with impact on local community livelihood, and subsequently to vote to select the most influential factors. Different future states for the year 2038, resulting from the impact of the factors of change, were discussed. In a follow-up workshop, participants were asked to propose activities that would support the development towards the most desirable scenario. In addition, a questionnaire was distributed through semi-structured/structured interviews to 126 households in nine villages.

Results were largely similar and complementary between the two approaches. Preferred interventions were: restocking herds with locally adapted breeds, training in livestock management, marketing support, feed development and value addition, loan schemes for investment in livestock production and support for animal health interventions to reduce the heavy disease burden. Whereas the participatory process is time consuming and requires considerable human resources, it is important to ensure locally relevant interventions are chosen, and it is in itself part of the process towards successful implementation of these interventions.

The study is thoughtfully designed based on previous work by the authors. The paper is well written and has been further improved through the reviewer feedback and revision process.

References

Caron, A., Miguel, E., Gomo, C., Makaya, P., Pfukenyi, D.M., Foggin, C., Hove, T. and de Garine-Wichatitsky, M., 2013. Relationship between burden of infection in ungulate populations and wildlife/livestock interfaces. Epidemiology & Infection, 141 (7), pp.1522-1535. https://doi.org/10.1017/S0950268813000204

Caron, A., Mugabe, P., Bourgeois, R., Delay, E., Bitu, F., Ducrot, R., Fafetine, J., Fynn, R., Guerbois, C., Motsholapheko, M. and Daré, W., 2022. Social-ecological System Health in  Transfrontier Conservation Areas to Promote the Coexistence Between People and Nature. One Health Cases. https://doi.org/10.1079/onehealthcases.2022.0005 

Cumming, D. H. M. 2011. Constraints to conservation and development success at the wildlife-livestock-human interface in southern African transfrontier conservation areas: a preliminary review. Wildlife Conservation Society, New York.  http://www.wcs-ahead.org/workinggrps_kaza.html

Gobvu, V. Ncube, S. Imbayarwo-Chikosi, V.E., Bourgeois, R. Mugabe, P.H. and Caron A. 2025. Preferred livestock interventions for small-scale farmers in the Great Limpopo Transfrontier Conservation Area: a demand-driven and participatory approach. HAL, ver.5 peer-reviewed and recommended by PCI Animal Science. https://hal.science/hal-04060712

Matseketsa, G., Muboko, N., Gandiwa, E., Kombora, D.M. and Chibememe, G., 2019. An assessment of human-wildlife conflicts in local communities bordering the western part of Save Valley Conservancy, Zimbabwe. Global Ecology and Conservation, 20, p.e00737. https://doi.org/10.1016/j.gecco.2019.e00737 

Tui, S.H.K., Descheemaeker, K., Valdivia, R.O., Masikati, P., Sisito, G., Moyo, E.N., Crespo, O., Ruane, A.C. and Rosenzweig, C., 2021. Climate change impacts and adaptation for dryland farming systems in Zimbabwe: a stakeholder-driven integrated multi-model assessment. Climatic Change, 168 (1-2), p.10. https://doi.org/10.1007/s10584-021-03151-8 

South African Development Community. 2025. Transfrontier Conservation Areas.  . Consulted 7 January 2025. https://www.sadc.int/pillars/transfrontier-conservation-areas

Many cognitive studies use paradigms based on active decision-making, that require that animals are motivated to participate and interested in the reward (e.g. Rivas-Blanco et al., 2023). By contrast, looking time paradigms, in which the visual attention of an animal to a stimulus is measured, requires little training and little action from the subject, and can be used without reinforcement (e.g. Wilson et al., 2023). 

In this methodological paper, Jana Deutsch and her collaborators investigated the possibility of using a looking time paradigm to study perception and cognition in goats. The advantage of such a paradigm would be that it requires little training and can be used with no reinforcement. Goats were observed in front of two video screens presenting pictures of goats (familiar or not), of humans (familiar or not), or remaining white. The authors hypothesised that goats would pay more attention to pictures than to a white screen, would pay more attention to goats than to humans, and would discriminate familiar vs. unfamiliar beings. The goats had received previous positive contacts with the familiar humans. The goats were extensively habituated to the experimental set-up so that stress did not interfere in responses to testing. The stimuli were presented on the screens in a pseudorandomized and counterbalanced order.

As hypothesised, goats looked longer at screen with pictures, and longer when the picture was that of another goat (familiar or not) than of a human being. Goats however did not seem to discriminate between familiar and unfamiliar being, or were equally motivated by the two types of beings. Ear postures were also recorded but did not show a relation with looking time and were not related to the type of picture shown on screens. Therefore, the authors argue that looking time but not ear posture is considered appropriate to test discrimination abilities or preferences in goats. More studies are needed to check if goats can differentiate familiar vs. unfamiliar beings.

The experimental design is sound. The statistical analyses are rigorous and very relevant.  The paper is clearly written.

I recommend the manuscript for publication for its originality and its quality; In addition, the paper bring findings – that looking time is an adequate paradigm in goats to analyse how they pay attention to stimuli – that have potential impacts on further studies in animal cognition.

References

Deutsch, J., Lebing, S., Eggert, A., Nawroth, C. (2024). Goats who stare at video screens – assessing behavioural responses of goats towards images of familiar and unfamiliar con- and heterospecifics. OSF, ver.4 peer-reviewed and recommended by Peer Community In Animal Science. https://doi.org/10.31219/osf.io/d4nzk

Rivas-Blanco, D., Monteiro, T., Virányi, Z., Range, F. (2024). Going back to “basics”: Harlow’s learning set task with wolves and dogs. Learning & Behavior. https://doi.org/10.3758/s13420-024-00631-6 

Wilson, V. A. D., Bethell, E. J., Nawroth, C. (2023). The use of gaze to study cognition: limitations, solutions, and applications to animal welfare. Frontiers in Psychology, 14:1147278. https://doi.org/10.3389/fpsyg.2023.1147278 

In production animals, behavioural activity plays a crucial role across a wide range of scientific disciplines and is often measured for various purposes depending on the field: ethology, animal welfare, reproduction, animal production, and so on. Historically, direct observation was the primary method of collecting such data, a process that was time-consuming and prone to possible observer bias. With the advent of automated systems and sensors, behavioural activity can now be recorded continuously and non-invasively, leading to a growing body of more reliable data  (1). However, the lack of standardisation in how these data are calculated and interpreted has created challenges for cross-study comparisons. To fully harness the potential of studying behavioural activity, scientific studies must harmonise the methods used to calculate this measure. Standardising these methods would make it easier to compare results and identify possible gaps in knowledge.

In the work by van Dixhoorn et al.(2), the authors examine the various metrics most commonly used to study behavioural activity. Through a series of examples, they address the definitions, calculation methods, and biological significance of metrics such as overall activity, fluctuations around mean activity, cyclicity of activity, and synchrony between animals. The authors suggest how these different metrics can be applied in specific contexts and guide readers in using appropriate terminology to ensure future studies are more easily comparable. In addition, by clarifying these concepts, the authors provide researchers with the tools to make informed decisions about which metric best suits their study's objectives.

A key contribution of this work is its emphasis on standardising the metrics and terminology used in behavioural activity studies. Studies using different metrics may arrive at conclusions that appear contradictory, not because of actual differences in animal behaviour, but due to inconsistencies in how behaviour is quantified. By advocating for a common framework, the authors aim to improve the replicability of studies, facilitate meta-analyses, and allow for a more cohesive understanding of animal behaviour across different research groups. This, in turn, could accelerate the identification of key behavioural indicators, ultimately leading to better animal management practices and welfare assessments.

This article provides a timely and valuable contribution to the field of animal science. As technology continues to evolve, so too must our methods for interpreting the vast amounts of data it generates (3). By ensuring that studies are comparable and data is interpreted consistently, the research community can work towards more meaningful discoveries in animal behaviour. I highly recommend this paper to researchers looking to deepen their understanding of activity metrics in animal behaviour studies.

References

1. Rushen J, Chapinal N, de Passilé AM (2012). Automated monitoring of behavioural-based animal welfare indicators. Animal Welfare 21(3):339-50. https://doi.org/10.7120/09627286.21.3.339 

2. van Dixhoorn IDE, Aubé L, van Zyl C, de Mol R, van der Werf J, Lardy R, Mialon MM, van Reenen CG, and Veissier I (2024). From data on gross activity to the characterization of animal behaviour: which metrics for which purposes?. Zenodo, 10420600, ver.5 peer-reviewed and recommended by PCI Animal Science. https://doi.org/10.5281/zenodo.10420600 

3. Riaboff L, Shalloo L, Smeaton AF, Couvreur S, Madouasse A, Keane MT (2022). Predicting livestock behaviour using accelerometers: A systematic review of processing techniques for ruminant behaviour prediction from raw accelerometer data. Computers and Electronics in Agriculture 192:106610. https://doi.org/10.1016/j.compag.2021.106610 
 

"Ensuring ethical animal welfare research: Are more ethics review committees the solution?" by Birte Nielsen and colleagues [1] provides food for thought on the ethical assessment of experiments involving farm animals. While regulations can provide a precise framework, they differ from country to country and do not consider several cases, mainly when the experimentation involves non- or minimally invasive manipulations. It is also the case when research projects use farmed animals that do not fall within the scope of the regulations on animal experimentation but have undergone practices that can be authorised on farms but may raise ethical questions (tail docking, live castration, tooth filing, beak trimming, dehorning). On the other hand, the heterogeneity of the criteria taken into account by the ethics committees, when they exist (and this can differ greatly from one country to another), do not necessarily correspond to the criteria of the journals, the reviewers and the bodies brought in to evaluate the research project, or to the regulations specific to each country.  

All these paradoxes lead the authors to propose solutions, the most straightforward and spontaneous of which is to ask ourselves questions about this issue upstream of the experimental design required to answer a given scientific question. While increasing the number of ethical review committees may be an insufficient option, the authors insist on the importance of improving committee members' training, taking into consideration jurisdictions' differences between countries and spending more time on ethics evaluation during manuscripts' reviewing. In addition, the upstream assessment of research projects by ethics committees, specific to an institution (research institute, universities, companies), a scientific publisher or even a dedicated international ethical review board may also be a good option.

The ethical evaluation of research projects is a question at the heart of our research activities, for which we do not have all the answers. As with scientific reviewing, we must take on the role of evaluator or be evaluated ourselves, using criteria and feelings that are not always consensual. The heterogeneity of evaluation systems within the scientific community, the lack of training for scientists in the fundamentals of ethical evaluation, and the different perceptions of the animal condition between countries and cultures can lead to a reciprocal lack of understanding between evaluator and evaluated, and sometimes a feeling of injustice, as some research may be easy to conduct in one country but difficult in another. Indeed, it is exciting to read the exchanges between the authors and the three reviewers who assessed this opinion paper to appreciate the diversity of points of view and see specific points of divergence.

In addition to animal experimentation, the judgment handed down on 30 June 2023 by the French court penalising a pig farmer for the abusive use of an authorised breeding practice (tail docking) is a perfect illustration of the fact that the ethical assessment of practices and handling of farm animals now extends far beyond the scientific world and is becoming an increasingly important factor in the relationship between society and animal breeding. Failure to consider this evolution, whether in experimentation or animal husbandry, may have legal consequences and increase the lack of understanding between our practices and how society perceives them. The questions raised and the solutions proposed in the article by Nielsen et al. are central to our concerns, not only for the scientific community but also to meet the expectations of all stakeholders.

Finally, although the authors do not directly address the question of genome editing and research using edited farm animals, this is and will be at the heart of future issues concerning the ethical evaluation of research projects. As with practices and manipulations, the intentionality of the modifications induced leads us to question and evaluate, in farmed species, their consequences on animal welfare and their relevance to society and the development of more sustainable and socially accepted animal husbandry.

Reference

[1] Nielsen, B. L., Golledge, H. D. R., Chou, J., Camerlink, I., Pongrácz, P., Ceballos, M., Whittaker, A. L., Olsson, I. S. (2023) Ensuring ethical animal welfare research: Are more ethics review committees the solution? OSF Preprints. Ver. 3 peer-reviewed and recommended by Peer Community in Animal Science. https://doi.org/10.31219/osf.io/s6459