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. 
Martini, A., Huysseune, A., Witten, P. E. et al. 2021. Plasticity of the skeleton and skeletal deformities in zebrafish (Danio rerio) linked to rearing density. Journal of Fish Biology 98(4), 971-986.

The teleost zebrafish (Danio rerio), an established model for human skeletal diseases, is reared under controlled conditions with defined parameters for temperature and photoperiod. Studies aimed at defining the proper rearing density have been performed...

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)...

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...

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...

de A. P. Ramos, G., de Azevedo, C. S., Jardim, T. H. A. et al. 2021. Temperament in captivity, environmental enrichment, flight ability, and response to humans in an endangered parrot species. Journal of Applied Animal Welfare Science 24(4), 379-391.

Temperament assessment is useful in reintroduction programs. Reactivity to humans and flight ability are also important behavioral aspects for captive parrots candidates to reintroduction. The study aimed: a) to evaluate if behavioral responses to environmental...

Andersson, M., Kettunen, P. 2021. Effects of holding density on the welfare of zebrafish: A systematic review. Zebrafish 18(5), 297-306.

The zebrafish is becoming an increasingly popular research animal around the world. Its welfare is affected by an array of environmental factors, such as food access and water quality. Holding density is an important welfare...

Padalino, B., Raidal, S. 2020. Effects of transport conditions on behavioural and physiological responses of horses. Animals 10(1), 160.

The regulations for minimal space and direction of travel for land transport in horses vary worldwide and there is currently no definitive guidance to promote equine health and welfare. This study evaluated the effects of...

Raspa, F., Tarantola, M., Bergero, D. et al. 2020. Stocking density affects welfare indicators in horses reared for meat production. Animals 10(6), 1103.

Horses kept for meat production are reared in intensive breeding farms. We employed a checklist adapted from the Animal Welfare Indicators (AWIN) assessment protocol. Our evaluation aims to assess whether welfare indicators are influenced by...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Acharya, R., Rault, J.-L. 2020. Risk factors for feather-damaging behavior in companion parrots: A social media study. Journal of Veterinary Behavior 40, 43-49.

Studies on the etiology of behavioral problems often involve interference in the animal's routine or reliance on owners' self-reports like surveys. Gathering data from videos posted on social media, a technique coined ‘video mining’, offers...

Rankins, E. M., Wickens, C. L. 2020. A systematic review of equine personality. Applied Animal Behaviour Science 231, 105076.

Examining the literature suggests equine personality is of interest to behavior and welfare scientists and those involved in the equine industry. Study and assessment of personality is critical because of the profound implications certain traits...

Raspa, F., Tarantola, M., Bergero, D. et al. 2020. Time-budget of horses reared for meat production: Influence of stocking density on behavioural activities and subsequent welfare. Animals 10(8), 1334.

Horses reared for meat production can be kept in intensive breeding farms where they are housed in group pens at high stocking densities. The present study aimed to evaluate whether the expressed behaviours correlated with...

Pedersen, I. J., Forkman, B. 2019. Improving leg health in broiler chickens: A systematic review of the effect of environmental enrichment. Animal Welfare 28(2), 215-230.

Leg problems are highly prevalent in modern broiler production and provision of environmental enrichment could be a strategy to improve leg health. Different types of environmental enrichment have undergone evaluation. Our objective was to conduct...

Solås, M. R., Skoglund, H., Salvanes, A. G. V. 2019. Can structural enrichment reduce predation mortality and increase recaptures of hatchery-reared Atlantic salmon Salmo salar L. fry released into the wild? Journal of Fish Biology 95(2), 575-588.

Captive-reared fish often have poor survival in the wild and may fail to boost threatened populations. Enrichment during the nursery period can in some circumstances generate a broader behavioural repertoire than conventional hatchery production. Yet...

Ijichi, C., Green, S., Squibb, K. et al. 2019. Zylkéne to load? The effects of alpha-casozepine on compliance and coping in horses during loading. Journal of Veterinary Behavior 30, 80-87.

Horses are routinely transported for access to safe off-road riding, veterinary care, breeding, sale, or moving to a new home environment. However, transport is a known stressor in horses. For this reason, problem behavior when...

Jung, L., Knierim, U. 2019. Differences between feather pecking and non-feather pecking laying hen flocks regarding their compliance with recommendations for the prevention of feather pecking – A matched concurrent case-control design. Applied Animal Behaviour Science 219, 104839.

Feather pecking (FP) is a multifactorial problem in all housing systems. Using a case-control design we wanted to determine a set of variables which may be decisive for a flock to become case or control...

Sanchez-Casanova, R., Sarmiento-Franco, L., Segura-Correa, J. et al. 2019. Effects of outdoor access and indoor stocking density on behaviour and stress in broilers in the subhumid tropics. Animals 9(12), 1016.

Studies investigating the welfare of commercial-line broiler chickens raised in houses with outdoor access in the tropics are scarce, and none have investigated whether responses vary according to indoor conditions. Hence, we assessed the effects...

Riddle, E. R., Ali, A. B. A., Campbell, D. L. M. et al. 2018. Space use by 4 strains of laying hens to perch, wing flap, dust bathe, stand and lie down. PLOS ONE 13(1), e0190532.

The laying hen industry is implementing aviary systems intended to improve welfare by providing hens with more space and resources to perform species-specific behaviors. To date, limited research has examined spatial requirements of various strains...

Santurtun, E., Broom, D. M., Phillips, C. J. C. 2018. A review of factors affecting the welfare of Atlantic salmon (Salmo salar). Animal Welfare 27(3), 193-204.

In the expanding salmon industry, many farmers use production methods that could result in poor welfare of the fish at various points of their lifecycle. We have reviewed methods used for producing salmon for food...

Champneys, T., Castaldo, G., Consuegra, S., et al. 2018. Density dependent changes in neophobia and stress-coping styles in the world’s oldest farmed fish. Royal Society Open Science 5(12), 181473.

Farmed fish are typically reared at densities much higher than those observed in the wild, but to what extent crowding results in abnormal behaviours that can impact welfare and stress coping styles is subject to...

Zepp, M., Louton, H., Erhard, M. et al. 2018. The influence of stocking density and enrichment on the occurrence of feather pecking and aggressive pecking behavior in laying hen chicks. Journal of Veterinary Behavior 24, 9-18.

The housing conditions and environments experienced during the rearing period can influence the development of feather pecking in chickens during this time and in the subsequent laying period. The aim of this study was to...

Mortell, D., Moores, S. 2017. Increasing survival rates in the Zebrafish (Zebra danio) at the University of Manchester. Animal Technology and Welfare 16(3), 214-215.

The average survival rate for our Zebrafish (ZF) embryos was 65%. When it was time to create our next generation of Wild Type (WT) (used for embryo production), we decided to run a trial focussing...

Vargas-Galicia, A. J., Sosa-Montes, E. Rodríguez-Ortega, L. T. et al. 2017. Effect of litter material and stocking density on bone and tendon strength, and productive performance in broilers. Canadian Journal of Animal Science 97(4), 673-682.

Litter material and stocking density were evaluated on welfare-related variables and productive performance in broilers. Male chicks (n = 744, “Ross 308” strain) were raised on either tezontle (TEZ) or wood shavings (WS) litter, with...

Yin, L., Yang, H., Xu, L. et al. 2017. Feather performance, walking ability, and behavioral changes of geese in response to different stocking densities. Applied Animal Behaviour Science 196, 108-112.

In recent decades, goose production has become more specialized and widespread, and rearing geese in plastic wire-floor pens is common in China. This type of rearing pattern is more productive than other rearing patterns since...

Marino, L. 2017. Thinking chickens: A review of cognition, emotion, and behavior in the domestic chicken. Animal Cognition 20(2), 127–147.

Domestic chickens are members of an order, Aves, which has been the focus of a revolution in our understanding of neuroanatomical, cognitive, and social complexity. At least some birds are now known to be on...