Refinement Database

Database on Refinement of Housing, Husbandry, Care, and Use of Animals in Research

This database, created in 2000, is updated every four months with newly published scientific articles, books, and other publications related to improving or safeguarding the welfare of animals used in research.

Tips for using the database:

  • This landing page displays all of the publications in the database.
  • Use the drop-down menus to filter these publications by Animal Type, Setting, and/or Topic.
  • Clicking on a parent category (e.g., Rodent) will include publications relating to all the items in that category (e.g., Chinchilla, Gerbil, Guinea Pig, etc.).
  • You may also add a keyword to further narrow your search.
  • Please note that at this time, only publications dated 2010 or later (with some exceptions) can be filtered by Animal Type and Topic, and only publications dated 2020 or later (with some exceptions) can be filtered by Setting. Most publications older than 2010 can only be searched by keyword. 
Chrzanowska, A., Modlinska, K., Goncikowska, K. et al. 2022. Rat’s response to a novelty and increased complexity of the environment resulting from the introduction of movable vs. stationary objects in the free exploration test. PLOS ONE 17(12), e0279006.

Most animals, including rats, show a preference for more complex environments. This is demonstrated particularly well when complexity increases due to the addition of new elements to the environment. The aim of the study was...

Mieske, P., Hobbiesiefken, U., Fischer-Tenhagen, C. et al. 2022. Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice. Frontiers in Veterinary Science 9, 899219.

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans...

O’Malley, C. I., Hubley, R., Tambadou, H. et al. 2022. Refining restraint techniques for research pigs through habituation. Frontiers in Veterinary Science 9, 1016414.

Pigs are common research models and are strong animals that can be difficult to restrain. Improper restraint can put pigs and research personnel at risk for injury and induce stress, which can affect research outcomes...

Parois, S. P., Van Der Zande, L. E., Knol, E. F. et al. 2022. A multi-suckling system combined with an enriched housing environment during the growing period promotes resilience to various challenges in pigs. Scientific Reports 12(1), 6804.

Little is known about the impact of social and environmental enrichment on improving livestock resilience, i.e. the ability to quickly recover from perturbations. We evaluated the effect of an alternative housing system (AHS) on resilience...

Pedersen, K., Kruhøffer, L. L., Lykkesfeldt, J. et al. 2022. Comparison of the neuromuscular effects of two infusion rates of rocuronium in anesthetized pigs. Acta Veterinaria Scandinavica 64(1), 38.

Neuromuscular blocking agents are frequently administered to pigs used for research. In humans, administration of the drugs is not without risk and may result in accidental awareness under general anaesthesia and postoperative residual neuromuscular blockade...

Reifenrath, J., Heider, M., Kempfert, M. et al. 2022. Buprenorphine in rats: Potent analgesic or trigger for fatal side effects? Acta Veterinaria Scandinavica 64(1), 37.

With ongoing animal welfare efforts, multimodal analgesia is often recommended to implement in study protocols. Buprenorphine with very potent analgesic effect is a standard opioid for the use in this context in rats. In this...

Wahltinez, S. J., Stacy, N. I., Hadfield, C. A. et al. 2022. Perspective: Opportunities for advancing aquatic invertebrate welfare. Frontiers in Veterinary Science 9, 973376.

Welfare considerations and regulations for invertebrates have lagged behind those for vertebrates, despite invertebrates comprising more than 95% of earth’s species. Humans interact with and use aquatic invertebrates for exhibition in zoos and aquaria, as...

Cait, J., Cait, A., Scott, R. W. et al. 2022. Conventional laboratory housing increases morbidity and mortality in research rodents: Results of a meta-analysis. BMC Biology 20(1), 15.

Over 120 million mice and rats are used annually in research, conventionally housed in shoebox-sized cages that restrict natural behaviours (e.g. nesting and burrowing). This can reduce physical fitness, impair thermoregulation and reduce welfare (e.g...

Giral, M., Armengol, C., Gavaldà, A. 2022. Physiologic effects of housing rats in metabolic cages. Comparative Medicine 72(5), 298–305.

Currently, metabolic cages (MC) are the only way to achieve serial sampling of urine and feces in rodents. However, the use of this caging creates a dramatic change from an animal’s usual microenvironment. Here we...

Zhang, H., Zhu, B., Yu, L. et al. 2022. Shelter color selection of juvenile swimming crabs (Portunus trituberculatus). Fishes 7(5), 296.

Color preference testing for animals is a prerequisite for optimizing facilities and ensuring animal welfare in aquaculture. Swimming crabs (Portunus trituberculatus) are aggressive, and shelters are often installed in ponds to reduce the high mortality...

Molina, S. J., Lietti, Á. E., Carreira Caro, C. S. et al. 2022. Effects of early noise exposure on hippocampal-dependent behaviors during adolescence in male rats: Influence of different housing conditions. Animal Cognition 25(1), 103–120.

Central nervous system (CNS) development is a very complex process that can be altered by environmental stimuli such as noise, which can generate long-term auditory and/or extra-auditory impairments. We have previously reported that early noise...

Whitbread, S. 2022. Some observations on the use of transparent barriers. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 49(3), 9-13.

What follows are some case studies in which solid but transparent barriers have been used successfully to provide a sense of security to three different mammal taxa (three-banded armadillo; Kirk’s dikdik; black rat) to reduce...

Costa, R., Carvalho, M. S. M., Brandão, J. D. P. et al. 2021. Modulatory action of environmental enrichment on hormonal and behavioral responses induced by chronic stress in rats: Hypothalamic renin-angiotensin system components. Behavioural Brain Research 397, 112928.

Environmental enrichment (EE) has been studied as a protocol that can improve brain plasticity and may protect against negative insults such as chronic stress. The aim of this study was to evaluate the effects of...

Wallgren, T., Gunnarsson, S. 2021. Effect of straw provision in racks on tail lesions, straw availability, and pen hygiene in finishing pigs. Animals 11(2), 379.

Unfulfilled exploratory behavior in pigs has been linked to tail biting, which causes reduced performance and welfare. Provision of straw can reduce tail biting, but large straw rations can cause poor hygiene in pens. This...

Pol, F., Huneau-Salaün, A., Gallien, S. et al. 2021. Compressed brown algae as a potential environmental enrichment material in growing pigs. Animals 11(2), 315.

In barren housing conditions, enrichment materials are given to pigs to improve their welfare. Here, we assessed the suitability of an algae-based cylinder as an enrichment material on the behavioral, physiological, health and productivity welfare...

Lambert, K. 2021. DIY: Ice cream cone spiced foraging cups. Laboratory Animal Science Professional 9(1) (January/February), 36.

This DIY snack is great for NHPs and can be customized in a variety of ways.

Lambert, K. 2021. DIY: Ice produce blocks. Laboratory Animal Science Professional 9(2) (March/April), 41.

This great cool-down snack is ideal for group or singly housed swine or nonhuman primates (particularly in larger pen-style housing). This item can be customized for canines as well by modifying the liquid used and/or...

Monnas, J. 2021. DIY: Creating a rat play cage. Laboratory Animal Science Professional 9(2) (March/April), 46-48.

To provide extra enrichment for our training rats (Sprague Dawley; CRL: SD), our team discussed the idea of developing a rat play cage. Animals are housed in the Comparative Bioscience Center at The Rockefeller University...

Guisnet, A., Maitra, M., Pradhan, S. et al. 2021. A three-dimensional habitat for C. elegans environmental enrichment. PLOS ONE 16(1), e0245139.

As we learn more about the importance of gene-environment interactions and the effects of environmental enrichment, it becomes evident that minimalistic laboratory conditions can affect gene expression patterns and behaviors of model organisms. In the...

Katz, E. M., Huss, M. K., Jampachaisri, K. et al. 2021. Buprenorphine, but not lidocaine, effectively attenuates post-operative thermal hypersensitivity in an incisional model in neonatal rats (Rattus norvegicus). Scandinavian Journal of Laboratory Animal Science 47(1), 1-11.

There is limited information on safe and effective neonatal rodent analgesia. The aim of this study was to evaluate the efficacy and duration of analgesia provided by buprenorphine (Bup) and lidocaine (Lid) in an incisional...

Li, J.-Y., Kuo, T. B. J., Hung, C.-T. et al. 2021. Voluntary exercise enhances hippocampal theta rhythm and cognition in the rat. Behavioural Brain Research 399, 112916.

Regular exercise promotes learning and memory functions. Theta activity is known to relate to various cognitive functions. An increase in theta power may be related to higher cognitive functioning and learning functions. However, evidence is...

Swan, K.-M., Telkänranta, H., Munsterhjelm, C. et al. 2021. Access to chewable materials during lactation affects sow behaviour and interaction with piglets. Applied Animal Behaviour Science 234, 105174.

We investigated how providing chewable materials to piglets during the early weeks of life affect sow behaviour, sow and piglet interaction and sow health in pens with farrowing crates. We divided 59 pregnant sows into...

Aparecida Martins, R., Ribeiro Caldara, F., Crone, C. et al. 2021. Strategic use of straw as environmental enrichment for prepartum sows in farrowing crates. Applied Animal Behaviour Science 234, 105194.

Sows are highly motivated to build a nest prior to farrowing, but, given the barren environment of farrowing crates, this behaviour is limited and improperly expressed. We aimed to assess the effects of a straw...

Kauselmann, K., Krause, E. T., Glitz, B. et al. 2021. Effect of plant-based enrichment materials on exploration in rearing and fattening pigs (Sus scrofa domesticus). Applied Animal Behaviour Science 236, 105261.

When pigs cannot perform innate species-specific behaviours (e.g. rooting or chewing), behavioural disorders, like tail biting, can occur. However, it seems that various enrichment materials enhance the pigs to perform exploration behaviour and therefore can...

Fischer, M. L., Rodrigues, G. S., Aguero, W. P. et al. 2021. Refinement as ethics principle in animal research: Is it necessary to standardize the environmental enrichment in laboratory animals? Anais da Academia Brasileira de Ciências, 93(1), e20191526.

The Environmental enrichment technique, although scientifically recognized for raising the level of animal welfare, has led to the questioning of its influence on the results of experimental research. Thus, the goal is to promote reflection...