You and your research report: implementing the ARRIVE reporting guideline

Machine perfusion of the liver and in vivo animal models: A systematic review of the preclinical research landscape

Machine perfusion (MP) is often referred to as one of the most promising advancements in liver transplantation research of the last few decades, with various techniques and modalities being evaluated in preclinical studies using animal models. However, low scientific rigor and subpar reporting standards lead to limited reproducibility and translational potential, hindering progress. This pre-registered systematic review (PROSPERO: CRD42021234667) aimed to provide a thematic overview of the preclinical research landscape on MP in liver transplantation using in vivo transplantation models and to explore methodological and reporting standards, using the ARRIVE (Animal Research: Reporting of In Vivo Experiments) score. In total 56 articles were included. Studies were evenly distributed across Asia, Europe, and the Americas. Porcine models were used in 57.1% of the studies, followed by rats (39.3%) and dogs (3.6%). In terms of graft type, 55.4% of the studies used donation after cardiac death grafts, while donation after brain death grafts accounted for 37.5%. Regarding MP modalities, the distribution was as follows: 41.5% of articles utilized hypothermic MP, 21.5% normothermic MP, 13.8% subnormothermic MP, and 16.9% utilized hypothermic oxygenated MP. The stringent documentation of ARRIVE elements concerning precise experimental execution, group size and selection, the choice of statistical methods, as well as adherence to the principles of the 3Rs, was notably lacking in the majority of publications, with less than 30% providing comprehensive details. Postoperative analgesia and antibiotics treatment were not documented in 82.1% of all included studies. None of the analyzed studies fully adhered to the ARRIVE Guidelines. In conclusion, the present study emphasizes the importance of adhering to reporting standards to promote reproducibility and adequate animal welfare in preclinical studies in machine perfusion. At the same time, it highlights a clear deficiency in this field, underscoring the need for further investigations into animal welfare-related topics.

Publication reform to safeguard wildlife from researcher harm

Despite abundant focus on responsible care of laboratory animals, we argue that inattention to the maltreatment of wildlife constitutes an ethical blind spot in contemporary animal research. We begin by reviewing significant shortcomings in legal and institutional oversight, arguing for the relatively rapid and transformational potential of editorial oversight at journals in preventing harm to vertebrates studied in the field and outside the direct supervision of institutions. Straightforward changes to animal care policies in journals, which our analysis of 206 journals suggests are either absent (34%), weak, incoherent, or neglected by researchers, could provide a practical, effective, and rapidly imposed safeguard against unnecessary suffering. The Animals in Research: Reporting On Wildlife (ARROW) guidelines we propose here, coupled with strong enforcement, could result in significant changes to how animals involved in wildlife research are treated. The research process would also benefit. Sound science requires animal subjects to be physically, physiologically, and behaviorally unharmed. Accordingly, publication of methods that contravenes animal welfare principles risks perpetuating inhumane approaches and bad science.

Conducting and reporting animal experimentation: Quo vadis?

Most scientific journals ask authors to include a statement in their articles that animal studies have been carried out in agreement with international regulations on the use and care of laboratory animals. This statement implies that all the experiments conducted on animals have been evaluated and accepted by an Ethical Committee and, that animal welfare has been put as a priority throughout the experimental protocol. Nevertheless, discrepancies are commonly found between the described procedures and the guidelines that are claimed to have been followed; this reveals a double dilemma. First, animal welfare is not always considered, implicating discomfort or even worse, suffering to animals involved. Secondly, revisions of manuscripts are sometimes done without taking into account ethical and regulatory aspects concerning the use of animals. Underestimation of pain or suffering, disregard for physiological parameters, and other examples recently reported in scientific journals by neuroscientists from all over the world are discussed in this article. In a period of great debate about the ethical use of animals, with society being involved and engaged in the discussion, this Neuro-Opinion intends to call the attention of researchers, ethical committee members, and journal editors about the need of strictly endorsing international regulations and placing animal welfare as the top priority.