Since alternative methods (AAs), such as in vitro cultures, organs in silico, or mathematical methods, are not fully able to reproduce the complexity of the human organism, particularly neu-ral processes, and brain structures, animal experimentation remains the only way in which re-search can obtain the necessary knowledge to suggest drug therapies or targeted therapeutic in-terventions. Particularly in neuroscience, transgenic animals allow us to model neurological dis-eases, study the relationship between the brain and behavior, and decipher the function of genes involved in pathological conditions. However, it should never be forgotten that animals are "sen-tient beings" capable of feeling pleasure and pain (Art. 13 of the 2007 Lisbon Treaty). For this rea-son, it is crucial to prioritize the welfare of animals involved in testing by considering their phys-ical, psychological, adaptive, and relational well-being. This is where the concept of a Culture of Care comes in, where the responsibility of care extends beyond the veterinary aspects to include everything that can safeguard the welfare of animals before, during, and after experimentation. This chapter explains the advantages of using the animal model while practicing the culture of care in neuroscience, as both animals and research outcomes benefit from this approach.

Malignant pleural mesothelioma (MPM) has limited treatment options and poor prognosis. Frequent inactivation of the tumour suppressors BAP1, NF2 and P16 may differentially sensitise tumours to treatments. We have established chick chorioallantoic membrane (CAM) xenograft models of low-passage MPM cell lines and protocols for evaluating drug responses. Ten cell lines, representing the spectrum of histological subtypes and tumour suppressor status, were dual labelled for fluorescence/bioluminescence imaging and implanted on the CAM at E7. Bioluminescence was used to assess viability of primary tumours, which were excised at E14 for immunohistological staining or real-time PCR. All MPM cell lines engrafted efficiently forming vascularised nodules, however their size, morphology and interaction with chick cells varied. MPM phenotypes including local invasion, fibroblast recruitment, tumour angiogenesis and vascular remodelling were evident. Bioluminescence imaging could be used to reliably estimate tumour burden pre- and post-treatment, correlating with tumour weight and Ki-67 staining. In conclusion, MPM-CAM models recapitulate important features of the disease and are suitable to assess therapies using a broad range of MPM cell lines that allow histological or genetic stratification. They are amenable to multi-modal imaging, offering a time and cost-efficient, 3Rs-compliant alternative to rodent xenograft models to prioritise candidate compounds from in vitro studies.

The Developing Countries Vaccine Manufacturing Network coordinated a multi-laboratory study funded by the US National Institute for Innovation in Manufacturing Biopharmaceuticals to assess the performance of the Pertussis Serological Potency Test (PSPT) in the laboratories of seven whole-cell pertussis vaccine (wP) manufacturers and three National Control Laboratories based in Southeast Asian countries. To this end, common protocols for the immunization of mice and serological testing by ELISA were shared with all laboratories. Each laboratory used their own wP vaccines and the reference vaccine routinely used in the regulatory required mouse protection test (MPT) and assayed the products both in the MPT and PSPT. Whereas in all laboratories the PSPT showed decreased serum IgG levels after immunization with sub-potent compared to potent final batches, some issues were encountered during execution of the assay, which prevented drawing of definitive conclusions on assay performance. Nevertheless, the study provided the participants with the opportunity to familiarize themselves with the PSPT protocols and revealed the next steps to be addressed for implementation of the method.

Testing in animals is mandatory in drug testing and the gold standard for evaluation of toxicity. This situation is expected to change in the future because the 3Rs principle, which stands for replacement, reduction and refinement of the use of animals in science, is reinforced by many countries. On the other hand, technologies for alternatives to animals experiments have increased. The necessity to develop and use of alternatives is influenced by the complexity of the research topic and also by the fact, to which extent the currently used animal models can mimic human physiology and/or exposure. Rodent lung morphology and physiology differs markedly for that of humans and inhalation exposure of the animals are challenging. In vitro and in silico methods can assess important aspects of the in vivo action, namely particle deposition, dissolution, action at and permeation across the respiratory barrier and pharmacokinetics. Out of the numerous homemade in vitro and in silico models some are available commercially or open access. This review discusses limitations of animal models and exposure systems and proposes a panel of in vitro and in silico techniques that, in the future, may replace animal experimentation in inhalation testing.

Perinatal mortality is a major issue in laboratory mouse breeding. We compared a counting method using daily checks (DAILY_CHECK) with a method combining daily checks with detailed video analyses to detect cannibalisms (VIDEO_TRACK) for estimating the number of C57BL/6 pups born, died and weaned in 193 litters from trios with (TRIO-OVERLAP) or without (TRIO-NO_OVERLAP) the presence of another litter. Linear mixed models were used at litter level. To understand if cannibalism was associated with active killing (infanticide), we analysed VIDEO_TRACK recordings of 109 litters from TRIO-OVERLAP, TRIO-NO_OVERLAP or SOLO (single dams). We used Kaplan-Meier method and logistic regression at pup level. For DAILY_CHECK, the mean litter size was 35% smaller than for VIDEO_TRACK (P<0.0001) and the number of dead pups was twice lower (P<0.0001). The risk of pup loss was higher for TRIO-OVERLAP than TRIO-NO_OVERLAP (P<0.0001). A high number of pup losses occurred between birth and the first cage checking. Analyses of VIDEO_TRACK data indicated that pups were clearly dead at the start of most of the cannibalism events and infanticide was rare. As most pups die and disappear before the first cage check, many breeding facilities are likely to be unaware of their real rates of mouse pup mortality.