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)...

Rogers, L. J. 2023. Knowledge of lateralized brain function can contribute to animal welfare. Frontiers in Veterinary Science 10.

The specialized functions of each hemisphere of the vertebrate brain are summarized together with the current evidence of lateralized behavior in farm and companion animals, as shown by the eye or ear used to attend...

Hanh, H. Q., Phuong, N. T., Tien, N. D. et al. 2023. Effects of stocking density in group cages on egg production, profitability, and aggressive pecking of hens. Journal of Applied Animal Welfare Science 26(3), 374–385.

There is an increasing concern about welfare issues related to battery cages, which are commonly used in Vietnam, and requires a modified cage that improves hen welfare while retaining its economic and management advantages. We...

Webb, J. K., Keller, K. A., Chinnadurai, S. K. et al. 2023. Use of alfaxalone in bearded dragons (Pogona vitticeps): Optimizing pharmacodynamics and evaluating cardiogenic effects via echocardiography. Journal of the American Veterinary Medical Association 261(1), 126–131.

OBJECTIVE Bearded dragons (Pogona vitticeps), a popular zoological companion species, frequently require sedation for procedures. A novel formulation of alfaxalone with preservatives was FDA approved for 28-day use after the vial is breached. Research has...

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...

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...

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...

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...

Young, T., Whiteside, T., Locklear, J. 2020. What is your tattoo ink telling you? Laboratory Animal Science Professional 8(2) (March/April), 62-65.

Tattooing traumatizes the skin, which can result in microbial infections with the severity ranging from minor to life-threating septicemia. Additionally, the metals in colored tattoo ink are known to cause dermal inflammation in some people...

Zemanova, M. A. 2020. Towards more compassionate wildlife research through the 3Rs principles: Moving from invasive to noninvasive methods. Wildlife Biology 2020(1), no page numbers.

Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive...

Larson, C. M., Wilcox, G. L., Fairbanks, C. A. 2019. Defining and managing pain in stroke and traumatic brain injury research. Comparative Medicine 69(6), 510–519.

Neurologic conditions such as stroke and traumatic brain injury are challenging conditions to study in humans. Animal models are necessary to uncover disease processes and develop novel therapies. When attempting to model these or other...

Rasys, A. M., Divers, S. J., Lauderdale, J. D. et al. 2020. A systematic study of injectable anesthetic agents in the brown anole lizard (Anolis sagrei). Laboratory Animals 54(3), 281–292.

Anolis lizards have served as important research models in fields ranging from evolution and ecology to physiology and biomechanics. However, anoles are also emerging as important models for studies of embryo development and tissue regeneration...

Clutton, R. E. 2020. An Anglocentric history of anaesthetics and analgesics in the refinement of animal experiments. Animals 10(10), 1933.

Previous histories of animal experimentation, e.g., Franco (2013) have focused on ethics, the law and the personalities involved, but not on the involvement of anaesthetics or analgesics. Given that these were major subjects of (UK)...

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...

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...

Bressan, T. F., Sobreira, T., Carregaro, A. B. 2019. Use of rodent sedation tests to evaluate midazolam and flumazenil in green iguanas (Iguana iguana). JAALAS 58(6), 810–816.

This study aimed to evaluate the applicability of rodent behavioral tests to assess the effects of midazolam and flumazenil in green iguanas. Four tests commonly used to assess sedation in rodents—the open field test, forced...

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...

Buijs, S., Booth, F., Richards, G. et al. 2018. Behavioural and physiological responses of laying hens to automated monitoring equipment. Applied Animal Behaviour Science 199, 17-23.

Automated monitoring of behaviour can offer a wealth of information in circumstances where observing behaviour is difficult or time consuming. However, this often requires attaching monitoring devices to the animal which can alter behaviour, potentially...

Fink, D. M., Doss, G. A., Sladky, K. K. et al. 2018. Effect of injection site on dexmedetomidine-ketamine induced sedation in leopard geckos (Eublepharis macularius). Journal of the American Veterinary Medical Association 253(9), 1146-1150.

OBJECTIVE To evaluate whether the sedative effects of a combination of dexmedetomidine and ketamine differed when it was administered IM in a hind limb versus a forelimb of leopard geckos (Eublepharis macularius). DESIGN Randomized crossover...

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...

Chatigny, F., Kamunde, C., Creighton, C. M. et al. 2017. Uses and doses of local anesthetics in fish, amphibians, and reptiles. JAALAS 56(3), 244-253.

Local anesthetics are an integral part of routine pain management in mammals, yet their use is relatively limited in fish, amphibians and reptiles. These animals frequently undergo potentially painful surgical procedures and therefore could possibly...

Reed, B., Beatham, S., Carter, S. et al. 2017. Report of a RSPCA/APHA meeting on the welfare of wild animals used in research. Animal Technology and Welfare 16(1), 13-25. [Meeting Report]

This is a report of a one-day meeting jointly convened by the RSPCA and the Animal and Plant Health Agency (APHA), which brought together around 70 researchers, veterinarians, animal technologists, regulators and others with an...