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. 
Kalies, A., Baumgartner, J., Beyerbach, M. et al. 2021. Interactive rooting towers and behavioural observations as strategies to reduce tail biting on conventional pig fattening farms. Animals 11(11), 3025.

Eight pens (25 pigs/pen; n = 200) provided with an interactive straw-filled rooting tower (experimental group) and five pens (25 pigs/pen; n = 125) with a stationary (fixed) tower without straw (control group) were compared...

Hakansson, F., Bolhuis, J. E., 2021. Tail-biting behaviour pre-weaning: Association between other pig-directed and general behaviour in piglets. Applied Animal Behaviour Science 241, 105385.

Tail biting in pigs is a damaging behaviour and remains an economic and welfare problem in modern pig production. Although tail biting has been extensively investigated, little is known about the behaviour in piglets. The...

de Jong, I. C., Blaauw, X. E., van der Eijk, J. E. J. et al. 2021. Providing environmental enrichments affects activity and performance, but not leg health in fast- and slower-growing broiler chickens. Applied Animal Behaviour Science 241, 105375.

Effects of environmental enrichment on activity, behaviour, walking ability, contact dermatitis and performance were investigated in fast- and slower-growing broiler chickens. A total of 840 day-old male broilers, 420 of a fast-growing strain (Ross 308)...

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...

Sirovnik, J., Euteneuer, P., König von Borstel, U. 2021. An attempt to use sound-imprinting to attract broilers onto elevated platforms for night-time roosting. Applied Animal Behaviour Science 243, 105448.

Welfare of fast growing broilers is often compromised due to leg health issues. A more complex environment such as the provision of elevated platforms facilitates activity and improves leg health in fast growing broilers. Thus...

Schmid, S. M., Steinhoff-Wagner, J. 2021. Behavior and body temperature alterations in piglets anesthetized for castration during a four-hour recovery phase. Applied Animal Behaviour Science 245, 105497.

One way to eliminate pain during surgical castration is to provide general anesthesia by intramuscular injection. However, its disadvantage is the long recovery phase, during which anesthetized piglets have to be separated from the sow...

MacLellan, A., Fureix, C., Polanco, A. et al. 2021. Can animals develop depression? An overview and assessment of “depression-like” states. Behaviour 158(14/15), 1303–1353.

Describing certain animal behaviours as 'depression-like' or 'depressive' has become common across several fields of research. These typically involve unusually low activity or unresponsiveness and/or reduced interest in pleasure (anhedonia). While the term 'depression-like' carefully...

Fynn, M., Crow, G., Connor, L. 2021. Pre-farrow enrichment with burlap sheet: potential benefit for sow performance. Canadian Journal of Animal Science 101(4), 781-787.

Burlap has been proposed as an enrichment option for the conventional farrowing crate environment. Our objectives were to determine if burlap sheets hung in farrowing crates were used by sows and piglets and had any...

Campbell, D. L. M., Lee, C. 2021. A perspective on strategic enrichment for brain development: Is this the key to animal happiness? Frontiers in Veterinary Science 8, 720422.

Livestock animals are sentient beings with cognitive and emotional capacities and their brain development, similar to humans and other animal species, is affected by their surrounding environmental conditions. Current intensive production systems, through the restrictions...

Dalmau, A., Sánchez-Matamoros, A., Molina, J. M. et al. 2021. Intramuscular vs. intradermic needle-free vaccination in piglets: Relevance for animal welfare based on an aversion learning test and vocalizations. Frontiers in Veterinary Science 8, 715260.

The aim of the present study was to compare intramuscular injection with a needle and intradermic needle-free vaccinations against porcine reproductive and respiratory syndrome (PRRS) in piglets at 28 days old by studying behavioral and...

Schodl, K., Wiesauer, L., Winckler, C. et al. 2021. Reduced stocking density and provision of straw in a rack improve pig welfare on commercial fattening farms. Frontiers in Veterinary Science 8, 656211.

The aim of this study was to investigate the impact of reduced stocking density in combination with provision of additional enrichment material on pig welfare on-farm. On three growing-finishing farms in Austria, in total 974...

Krugmann, K. L., Mieloch, F. J., Krieter, J. 2021. Can tail and ear postures be suitable to capture the affective state of growing pigs? Journal of Applied Animal Welfare Science 24(4), 411-423.

The present study examined whether tail and ear postures in fattening pigs (n = 228) housed in different environments could be suitable for assessing their affective state. In doing so, it investigated the appearance of...

Vinícius dos Santos, J., de Souza Farias, S., Pereira, T. L. et al. 2021. Preference for and maintenance of interest in suspended enrichment toys in confined growing pigs. Journal of Veterinary Behavior 45, 68-73.

The objective of the present study was to evaluate the preference for, interest in, and behavior of growing pigs provided with three different suspended enrichment toys in a four-compartment environmental preference chamber (EPC). Sixty pigs...

Watai, Y., Uchihashi, M. 2021. Group housing procedure of laboratory farm pigs. Laboratory Animal Science Professional 9(5) (September/October), 58-60.

Our initial attempt was to individually place pigs in cages according to the serial numbers assigned by the vendor and remove cage inserts to combine those that happened to be next to each other. Unfortunately...

D'Eath, R. B., Foister, S., Jack, M. et al. 2021. Changes in tail posture detected by a 3D machine vision system are associated with injury from damaging behaviours and ill health on commercial pig farms. PLOS ONE 16(10), e0258895.

To establish whether pig tail posture is affected by injuries and ill health, a machine vision system using 3D cameras to measure tail angle was used. Camera data from 1692 pigs in 41 production batches...

Lourenço da Silva, M. I., Almeida Paz, I., Chaves, G. et al. 2021. Behaviour and animal welfare indicators of broiler chickens housed in an enriched environment. PLOS ONE 16(9), e0256963.

The present study aimed to assess the influence of adding straw bales, step platforms, and laser projectors as environmental enrichment resources on the behaviour and welfare indicators of broiler chickens (Gallus gallus domesticus). A sample...

Fels, M., Schrey, L., Rauterberg, S. et al. 2021. Early socialisation in group lactation system reduces post-weaning aggression in piglets. Veterinary Record 189(12), e830.

Background: Pre-weaning group housing for sows and their litters is expected to enhance animal welfare. However, knowledge of potential benefits of pre-weaning socialisation for piglets after weaning is still lacking. Methods: Weaner pigs were mixed...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Environmental complexity positively impacts affective states of broiler chickens. Scientific Reports 11(1), 16966.

Affective state can bias an animal’s judgement. Animals in positive affective states can interpret ambiguous cues more positively (“optimistically”) than animals in negative affective states. Thus, judgement bias tests can determine an animal’s affective state...

Misra, S., Bokkers, E., Upton, J. et al. 2021. Effect of environmental enrichment and group size on the water use and waste in grower-finisher pigs. Scientific Reports 11(1), 16380.

The grower-finisher stage accounts for 64% of the total on-farm herd water use. Part of this is consumed by the pigs, but a part is also wasted. Drinking water usage and wastage is affected by...

Ludwiczak, A., Skrzypczak, E., Składanowska-Baryza, J. et al. 2021. How housing conditions determine the welfare of pigs. Animals 11(12), 3484.

Humans who care for pigs prefer an environment that not only allows the pigs to express their natural behaviors but also limits the development of aggression and stereotypes. Most of the behavioral and health problems...

Wood, B., Rufener, C., Makagon, M. M. et al. 2021. The utility of scatter feeding as enrichment: Do broiler chickens engage with scatter–fed items? Animals 11(12), 3478.

In recent years, welfare certification companies have encouraged the use of scatter feeding as enrichment material, though there is little scientific evidence to support a scatter feeding program. This study aimed to understand the impact...

Sans, E. C. de O., Tuyttens, F. A. M., Taconeli, C. A. et al. 2021. From the point of view of the chickens: What difference does a window make? Animals 11(12), 3397.

We aimed to investigate what broiler chickens prefer when given free choice between a barn side with artificial lighting only as opposed to the other barn side with natural light through glass windows and artificial...

Ciborowska, P., Michalczuk, M., Bień, D. 2021. The effect of music on livestock: Cattle, poultry and pigs. Animals 11(12), 3572.

The welfare of animals, especially those kept in intensive production systems, is a priority for modern agriculture. This stems from the desire to keep animals healthy, to obtain a good-quality final product, and to meet...

Güz, B. C., de Jong, I. C., Da Silva, C. S. et al. 2021 Effects of pen enrichment on leg health of fast and slower-growing broiler chickens. PLOS ONE 16(12), e0254462.

Pen enrichment for broiler chickens is one of the potential strategies to stimulate locomotion and consequently contribute to better leg health and welfare. This study was designed to evaluate effects of using a plethora of...

Costantino, A., Fabrizio, E., Calvet, S. 2021. The role of climate control in monogastric animal farming: The effects on animal welfare, air emissions, productivity, health, and energy use. Applied Sciences 11(20), 9549.

In the last decades, an engineering process has deeply transformed livestock houses by introducing fine-tuned climate control systems to guarantee adequate indoor climate conditions needed to express the maximum genetic potential of animals and to...