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. 
Evans, L., Brooks, G. C., Anderson, M. G. et al. 2023. Environmental complexity and reduced stocking density promote positive behavioral outcomes in broiler chickens. Animals 13(13), 2074.

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD)...

Hube, D., Bill, J., Knop, E. S. et al. 2023. Physical injuries and hair corticosterone concentration in rabbit kits from single- and group-housed does kept on a commercial farm. Animals 13(2), 196.

In intense breeding programs, rabbits are exposed to numerous stress factors which could affect their welfare and health. It has been suggested that group housing is more comfortable for does and similar to the living...

Krunt, O., Zita, L., Kraus, A. et al. 2023. Effects of genotype and housing system on rabbit does’ aggressive behaviors and injuries in smallholding conditions. Animals 13(8), 1357.

The objective of the study was to investigate the effects of housing (deep litter + concrete floor vs. deep litter + ground soil with the possibility to dig burrows), and genotype (Mecklenburg or Hyplus) on...

Papakitsos, G., Assouad, S., Papageorgiou, M. et al. 2023. Regrouping in dairy ewes—Effects on productive performance and specific behavioral traits. Animals 13(7), 1163.

The regrouping of ruminants is a common practice in dairy farms and is targeting at the improvement of milk production efficiency. However, changing the established hierarchy in a group affects both productivity and behavioral attributes...

Mocz, F., Michel, V., Janvrot, M. et al. 2022. Positive effects of elevated platforms and straw bales on the welfare of fast-growing broiler chickens reared at two different stocking densities. Animals 12(5), 542.

In conventional rearing systems, fast-growing broiler chickens commonly experience welfare issues, such as contact dermatitis, walking difficulties or a lack of expression of species-specific behaviours. Enriching their environment may be a way to improve their...

Orient, E., Guillén‐Salazar, F. 2022. Evaluation of social compatibility in an all‐male group of chimpanzees (Pan troglodytes) by means of social network analysis. Zoo Biology 41(1), 84-93.

The study here presented provides preliminary data regarding social compatibility of an all-male group of five chimpanzees (Pan troglodytes), assessed by means of a social network analysis (SNA). The study was conducted at the Fundació...

Fultz, A., Yanagi, A., Breaux, S. et al. 2022. Aggressive, submissive, and affiliative behavior in sanctuary chimpanzees (Pan Troglodytes) during social integration. Animals 12(18), 2421.

Chimp Haven is a sanctuary for chimpanzees being retired from biomedical research and from facilities that can no longer care for them. Chimpanzees often live in smaller groups in captive settings; however, Chimp Haven integrates...

Lee, V. E., Arnott, G., Turner, S. P. 2022. Social behavior in farm animals: Applying fundamental theory to improve animal welfare. Frontiers in Veterinary Science 9, 932217.

A fundamental understanding of behavior is essential to improving the welfare of billions of farm animals around the world. Despite living in an environment managed by humans, farm animals are still capable of making important...

Escribano, D., Doldán-Martelli, V., Cronin, K. A. et al. 2022. Chimpanzees organize their social relationships like humans. Scientific Reports 12(1), 16641.

Human relationships are structured in a set of layers, ordered from higher (intimate relationships) to lower (acquaintances) emotional and cognitive intensity. This structure arises from the limits of our cognitive capacity and the different amounts...

Mayes, B. T., Tait, L. A., Cowley, F. C. et al. 2022. Stocking density, restricted trough space, and implications for sheep behaviour and biological functioning. Frontiers in Veterinary Science 9, 965635.

Stocking density and trough space allowance can potentially impact sheep welfare during live export voyages. The aim of this study was to assess the welfare implications for sheep housed at five allometric stocking densities, with...

Schwarzer, A., Erhard, M., Schmidt, P. et al. 2022. Effects of stocking rate and environmental enrichment on the ontogeny of pecking behavior of laying hen pullets confined in aviary compartments during the first 4 weeks of life. Animals 12(19), 2639.

The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first...

van der Eijk, J. A. J., Gunnink, H., Melis, M. et al. 2022. Reducing stocking density benefits behaviour of fast- and slower-growing broilers. Applied Animal Behaviour Science 257, 105754.

The broiler industry has come under sustained pressure from welfare organizations to improve broiler welfare. Breed and stocking density are important factors for broiler welfare and are often specified as criteria for higher welfare systems...

Funkhouser, J. A., Mayhew, J. A., Mulcahy, J. et al. 2021. Human caregivers are integrated social partners for captive chimpanzees. Primates 62(2), 297–309.

In a captive environment, it is challenging to ensure the highest level of social and psychological well-being for species with naturally complex social organizations and structures. There is a growing need to meet the social...

Leeds, A., Boyer, D., Ross, S. R. et al. 2021. Patterns of wounding in mixed-sex social groups of western lowland gorillas (Gorilla gorilla gorilla). Applied Animal Behaviour Science 236, 105226.

Long-term, multi-institutional assessments have become a reliable tool for evaluating patterns of wounding in zoo-living primates, with results informing on best practices for species-specific care protocols and population management strategies. For western lowland gorillas (Gorilla...

Sørensen, D., Cloutier, S., Gaskill, B. (Eds.). 2021. Animal-centric Care and Management - Enhancing Refinement in Biomedical Research. CRC Press, Boca Raton, FL.

The concept of the 3Rs (Refinement, Reduction and Replacement) has been used as a framework for improving the welfare of laboratory animals for the last half century. By establishing an animal-centric view on housing and...

Phillips, H. N., Heins, B. J. 2021. Effects of outdoor stocking density on growth, feather damage and behavior of slow-growing free-range broilers. Animals 11(3), 688.

Access to pasture is a main benefit of free-range broiler housing systems, yet the level of outdoor stocking density on broiler animal welfare remains unsettled. The growth, feather damage, pasture ranging and behaviors were assessed...

Wilson-Welder, J. H., Frank, A. T. 2021. Use of food enrichment for medication delivery in large groups of sheep. Laboratory Animal Science Professional 9(3) (May/June), 40-43.

In a 2018 AALAS webinar on Sheep and Goat Analgesia, Dr. Susie Vogel, a small ruminant expert, introduced the concept of getting sheep and goats to willingly take medication by putting it in a tasty...

Kimm, S., Rauterberg, S. L., Bill, J. et al. 2021. Use of space, active and resting behaviour in fattening rabbits (Oryctolagus cuniculus) housed in a combi park system: A case study. Animal Welfare 30(4), 493-506.

In this case study, a housing system for rabbits (Oryctolagus cuniculus) was developed, complying with the new German Welfare Regulation, and evaluated on-farm with regard to the rabbits' behaviour during four fattening periods. The housing...

Onozawa, E., Azakami, D., Seki, S. et al. 2021. Effect of an insulation device in preventing hypothermia during magnetic resonance imaging examinations for dogs and cats under general anesthesia. Animals 11(8), 2378.

Dogs and cats under general anesthesia may develop hypothermia. When performing a magnetic resonance imaging (MRI) examination, it is not possible to place a magnetic material in the MRI room, and MRI equipment requires a...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Effect of environmental complexity and stocking density on fear and anxiety in broiler chickens. Animals 11(8), 2383.

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers’ attention bias (measure of anxiety)...

Gartland, K. N., Carrigan, J., White, F. J. 2021. Preliminary relationship between overnight separation and wounding in bachelor groups of western lowland gorillas (Gorilla gorilla gorilla). Applied Animal Behaviour Science 241, 105388.

Despite no significant difference in wounding between bachelor and mixed-sex groups of western lowland gorillas (Gorilla gorilla gorilla) in zoological settings, anecdotal concerns around the frequency and severity of wounding in bachelor groups have perpetuated...

Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

Zemanova, M. A. 2021. Noninvasive genetic assessment is an effective wildlife research tool when compared with other approaches. Genes 12(11), 1672.

Wildlife research has been indispensable for increasing our insight into ecosystem functioning as well as for designing effective conservation measures under the currently high rates of biodiversity loss. Genetic and genomic analyses might be able...

da Silva Medeiros Elidio, H., Coelho, J. W. R., Cavalcanti Pereira da Silva, L. C. et al. 2021. Housing density and aggression in Syrian hamsters. JAALAS 60(5), 506-509.

The Syrian hamster (Mesocricetus auratus) is a solitary and naturally territorial animal, with female hamsters being more aggressive than males. This behavior makes handling difficult because they are usually housed in groups, which can lead...

Pfoh, R., Tiddi, B., Di Bitetti, M. S. et al. 2021. Grooming site preferences in black capuchin monkeys: Hygienic vs. social functions revisited. American Journal of Primatology 83(12), e23336.

When primates groom each other, they tend to concentrate on those parts of the body they cannot efficiently self-groom (i.e., not visually accessible), and prefer to intensify grooming in areas with high hair density, thus...