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. 
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...

Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

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...

Hubert, S., Al-Ajeeli, M., Bailey, C. et al. 2019. The role of housing environment and dietary protein source on the gut microbiota of chicken. Animals 9(12), 1085.

The gut microbiota of chicken has received much attention due to its importance for bird health, food safety, and performance. In the United States, the impending transition to cage-free housing environments has raised many questions...

Fischer, C. P., Romero, L. M. 2019. Chronic captivity stress in wild animals is highly species-specific. Conservation Physiology 7(1), coz093.

Wild animals are brought into captivity for many reasons—conservation, research, agriculture and the exotic pet trade. While the physical needs of animals are met in captivity, the conditions of confinement and exposure to humans can...

Eusemann, B. K., Baulain, U., Schrader, L. et al. 2018. Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems. PLOS ONE 13(5), e0194974.

A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period...

Toscano, M., Booth, F., Richards, G. et al. 2018. Modeling collisions in laying hens as a tool to identify causative factors for keel bone fractures and means to reduce their occurrence and severity. PLOS ONE 13(7), e0200025.

Keel fractures represent a major productivity and welfare issue for the laying hen industry with greater than 50% of birds in recent surveys across various commercial operations and nations exhibiting some form of damage by...

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...

Kallio, P. A, Janczak, A. M., Valros, A. E. et al. 2018. Case control study on environmental, nutritional and management-based risk factors for tail-biting in long-tailed pigs. Animal Welfare 27(1), 21-34.

A case control study with a questionnaire was carried out to compare feeding practices, diet composition, housing and management in 78 herds with or without a history of tail-biting in undocked pigs (Sus scrofa) in...

Jansson, D.S. 2018 Gaining insights into the health of non-caged layer hens. Veterinary Record 182(12), 347-349.

To prevent injuries and mortality in commercial non-caged laying hens a range of strategies should be used, including vaccination, effective biosecurity routines, optimal management and nutrition. Injurious pecking, footpad lesions, keel bone fractures, reproductive and...

Fels, M., Lüthje, F., Faux-Nightingale, A. et al. 2018. Use of space and behavior of weaned piglets kept in enriched two-level housing system. Journal of Applied Animal Welfare Science 21(3), 267-282.

In this study, the possibility of introducing an elevated platform to a piglet pen was explored as a way of increasing available space and creating functional areas. On the platform, nine different manipulable materials were...

Chen, S., Xiang, H., Zhu, X. et al. 2018. Free dietary choice and free-range rearing improve the product quality, gait score, and microbial richness of chickens. Animals 8(6), 84.

Poultry welfare has been extensively studied; however, there is a lack of rigorous scientific knowledge relating to the different aspects of welfare factors and how this may contribute to the production quantity and product quality...

Chuppava, B., Visscher, C., Kamphues, J. 2018. Effect of different flooring designs on the performance and foot pad health in broilers and turkeys. Animals 8(5), 70.

Litter quality has a significant influence on the performance and foot pad health in poultry. The objective of this study was to evaluate the effects of different types of flooring designs on the performance and...

Sirovnik, J., Stratmann, A., Gebhardt-Henrich, S. G. et al. 2018. Feeding from perches in an aviary system reduces aggression and mortality in laying hens. Applied Animal Behaviour Science 202, 53-62.

Some commercial aviary systems for laying hens allow birds to access feed by standing on perches instead of platforms. Despite reports that providing laying hens with perches relates to reduced aggression and cannibalism, and increased...

Jung, L., Knierim, U. 2018. Are practice recommendations for the prevention of feather pecking in laying hens in non-cage systems in line with the results of experimental and epidemiological studies? Applied Animal Behaviour Science 200, 1-12.

Feather pecking (FP) in laying hens is an important animal welfare problem in practice, despite extensive research and increasing sources of advice for farmers. We aimed to give an overview over results from experimental and...

Gebhardt-Henrich, S. G., Toscano, M. J., Würbel, H. 2018. Use of aerial perches and perches on aviary tiers by broiler breeders. Applied Animal Behaviour Science 203, 24-33.

Perching, especially during the night, is an innate behaviour of chickens and the provision of perches is mandatory for laying hens in multiple countries. We examined whether broiler breeders of the fast (Ross 308) and...

Bailie, C. L., Baxter, M., O’Connell, N. E. 2018. Exploring perch provision options for commercial broiler chickens. Applied Animal Behaviour Science 200, 114-122.

Two related experiments involving broiler chickens are presented. Experiment 1 evaluated the use of six perch types: (1) an A-frame design (incorporating a platform and ramps), (2) a ‘flat top’ ramp, (3) a curved ramp...

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...

Kittelsen, K. E., Granquist, E. G., Aunsmo, A. L. et al. 2018. An evaluation of two different broiler catching methods. Animals 8(8), 141.

Catching is the first step in the pre-slaughter chain for broiler chickens. The process may be detrimental for animal welfare due to the associated handling. The aim of this pilot study was to compare two...

Campbell, D. L. M., Horton, B. J., Hinch, G. N. 2018. Using radio-frequency identification technology to measure synchronised ranging of free-range laying hens. Animals 8(11), 210.

Free-range laying hen systems provide individuals a choice between indoor and outdoor areas where range use may be socially influenced. This study used radio-frequency identification technology to track the ranging of individually-tagged hens housed in...

King, R. L., Baxter, E. M., Matheson, S. M. et al. 2018. Sow free farrowing behaviour: Experiential, seasonal and individual variation. Applied Animal Behaviour Science 208, 14-21.

Although sow confinement at farrowing is inherently stressful, farrowing crates remain in widespread commercial use. Sows adapt to their environment, however adaptation may be counter-productive if the farrowing system changes. The current study observed the...

Norman, K. I., Weeks, C. A., Pettersson, I. C. et al. 2018. The effect of experience of ramps at rear on the subsequent ability of layer pullets to negotiate a ramp transition. Applied Animal Behaviour Science 208, 92-99.

In commercial situations, laying hens must negotiate levels to reach resources such as food, water and litter. Providing ramps in aviary systems reduces collisions and resultant keel bone fractures in adults. We investigated whether providing...

Schild, S.-L. A., Rangstrup-Christensen, L., Bonde, M. et al. 2018. The use of a shaded area during farrowing and lactation in sows kept outdoors. Applied Animal Behaviour Science 209, 22-29.

The hut temperature in outdoor pig production during summer can exceed the upper critical temperature of lactating sows. Therefore, sows may experience hyperthermia, a condition which has several adverse consequences for the welfare of both...

Edwards, G. L., Michael, J. A., Parks., A. 2018. Agricultural animals as biomedical models: Occupational health and safety considerations. ILAR Journal 59(2), 161-167.

The use of agricultural animals in biomedical research is increasing. Their overall size and metabolic rate, organ size, longer gestation period, and other physiological similarities make them good candidates for animal models of human disease...

O’Rourke, D. P., Baccanale, C. L., Stoskopf, M. K. 2018. Nontraditional laboratory animal species (cephalopods, fish, amphibians, reptiles, and birds). ILAR Journal 59(2), 168-176.

Aquatic vertebrates and cephalopods, amphibians, reptiles, and birds offer unique safety and occupational health challenges for laboratory animal personnel. This paper discusses environmental, handling, and zoonotic concerns associated with these species.