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. 
Jones, P., Tahamtani, F., Pedersen, I. et al. 2020. The productivity and financial impacts of eight types of environmental enrichment for broiler chickens. Animals 10(3), 378.

Reduced mobility in broilers can contribute to leg health problems. Environmental enrichment has been suggested as one approach to combat this through stimulating increased physical activity. Past studies have tested the effect of environmental enrichments...

Baker, S. L., Robison, C. I., Karcher, D. M. et al. 2020. Keel impacts and associated behaviors in laying hens. Applied Animal Behaviour Science 222, 104886.

Factors contributing to the development of keel bone damage are not well understood. This study aimed to identify behaviors and cage structures associated with acceleration events experienced by individual hens at their keels as the...

van den Oever, A. C. M., Rodenburg, T. B., Bolhuis, J. E. et al. 2020. Relative preference for wooden nests affects nesting behaviour of broiler breeders. Applied Animal Behaviour Science 222, 104883.

Optimising nest design for broiler breeders has benefits for both the animals and the producers. The welfare of the hens will increase by providing preferred housing, while also reducing eggs laid outside the nests. These...

Thøfner, I., Hougen, H. P., Villa, C. et al. 2020. Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause. PLOS ONE 15(3), e0229735.

Keel bone fractures in laying hens have been described with increasing prevalence from several countries over the last twenty years and are considered one of the greatest welfare problems to the layer industry. In Denmark...

Armstrong, E. A., Rufener, C., Toscano, M. J. et al. 2020. Keel bone fractures induce a depressive-like state in laying hens. Scientific Reports 10(1), 3007.

In commercial flocks of laying hens, keel bone fractures (KBFs) are prevalent and associated with behavioural indicators of pain. However, whether their impact is severe enough to induce a depressive-like state of chronic stress is...

Oczak, M., Maschat, K., Baumgartner, J. 2020. Dynamics of sows’ activity housed in farrowing pens with possibility of temporary crating might indicate the time when sows should be confined in a crate before the onset of farrowing. Animals 10(1), 6.

One way to reduce the negative impact of farrowing crates on sow welfare is to limit confinement of sows from the onset of farrowing until the end of the critical period of piglets’ life a...

Kress, K., Weiler, U., Schmucker, S. et al. 2020. Influence of housing conditions on reliability of immunocastration and consequences for growth performance of male pigs. Animals 10(1), 27.

Immunocastration is a sustainable alternative to piglet castration but faces limited market acceptance. The phenomenon of non-responders has not to date been examined in detail, but adverse and stressful housing conditions (e.g., mixing of groups)...

Zhang, X., Li, C., Hao, Y. et al. 2020. Effects of different farrowing environments on the behavior of sows and piglets. Animals 10(2), 320.

We investigated the effect of different farrowing systems on the behavior of sows and piglets. In total, 22 hybrid sows (Yorkshire × Landrace) were randomly assigned into three farrowing systems, farrowing crate (FC), free farrowing...

Leonard, S., Xin, H., Brown-Brandl, T. et al. 2020. Effects of farrowing stall layout and number of heat lamps on sow and piglet production performance. Animals 10(2), 348.

Most farrowing facilities in the United States use stalls and heat lamps to improve sow and piglet productivity. This study investigated these factors by comparing production outcomes for three different farrowing stall layouts (traditional, expanded...

Chou, J.-Y., D’Eath, R. B., Sandercock, D. A. et al. 2020. Enrichment use in finishing pigs and its relationship with damaging behaviours: Comparing three wood species and a rubber floor toy. Applied Animal Behaviour Science 224, 104944.

Environmental enrichment in pig housing is a legal requirement under current EU legislation, but some recommended loose materials may cause obstructions in fully-slatted systems. Wood is an organic material that could be compatible with slatted...

Wendler, P., Ertl, N., Flügger, M. et al. 2020. Influencing factors on the foot health of captive Asian elephants (Elephas maximus) in European zoos. Zoo Biology 39(2), 109-120.

Pathological lesions of feet occur frequently in captive elephant populations. To improve foot health, it is important to identify risk factors associated with such pathologies. Several previous studies have analyzed potentially influencing factors but were...

O’Leary, N. W., Byrne, D. T., Garcia, P. et al. 2020. Grazing cow behavior’s association with mild and moderate lameness. Animals 10(4), 661.

Accelerometer-based mobility scoring has focused on cow behaviors such as lying and walking. Accuracy levels as high as 91% have been previously reported. However, there has been limited replication of results. Here, measures previously identified...

Bøgh, N., Agger, P., Omann, C. et al. 2020. New device for noninvasive telemetric monitoring of vital signs in healthy and newly operated piglets. JAALAS 59(1), 90–93.

Measuring vital signs is central to medical practice, but they are difficult to monitor in awake laboratory animals. We examined the feasibility of a noninvasive device [Cortrium C3 device] for telemetric assessment of respiration rate...

Hambrecht, S., Oerke, A.‐K., Heistermann, M. et al. 2020. Diurnal variation of salivary cortisol in captive African elephants (Loxodonta africana) under routine management conditions and in relation to a translocation event. Zoo Biology 39(3), 186–196.

The present study assessed the diurnal variation in salivary cortisol in captive African elephants during routine management (baseline) and in relation to a potential stressor (translocation) to evaluate to what extent acute stress may affect...

Parois, S. P., Duttlinger, A. W., Richert, B. T. et al. 2020. Effects of three distinct 2-week long diet strategies after transport on weaned pigs' short and long-term welfare markers, behaviors, and microbiota. Frontiers in Veterinary Science 7, 140.

Alternative feed supplements have shown promising effects in terms of performance, but their effects on welfare have had little evaluation. In the present study, we aimed at evaluating the effect of diet supplementation on welfare...

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...

Maschat, K., Dolezal, M., Leeb, C. et al. 2020. Duration of confinement and pen-type affect health-related measures of welfare in lactating sows. Animal Welfare 29(3), 339-352.

Temporary crating is considered as a step towards improved welfare in lactating sows. Therefore, the aim of this study was to investigate effects of confinement period (CP) and farrowing pen-type (PT) on health-related measures. Four...

Stracke, J., Klotz, D., Wohlsein, P. et al. 2020. Scratch the surface: Histopathology of foot-pad dermatitis in turkeys (Meleagris gallopavo). Animal Welfare 29(4), 419-432.

Foot-pad dermatitis (FPD) is an important indicator of animal welfare in turkeys (Meleagris gallopavo). The present study aimed to evaluate the reliability and validity of a commonly used five-point visual score (VC), assessing FPD based...

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...

Gebhardt-Henrich, S. G., Jordan, A., Toscano, M. J. et al. 2020. The effect of perches and aviary tiers on the mating behaviour of two hybrids of broiler breeders. Applied Animal Behaviour Science 233, 105145.

Broiler breeders are kept for the production of fertile eggs. They face serious welfare problems like aggressive behaviour of the males towards females during mating. Furthermore, broiler breeders are usually kept without perches which are...

Ipema, A. F., Gerrits, W. J. J., Bokkers, E. A. M. et al. 2020. Provisioning of live black soldier fly larvae (Hermetia illucens) benefits broiler activity and leg health in a frequency- and dose-dependent manner. Applied Animal Behaviour Science 230, 105082.

Fast-growing broilers spend most their time inactive and are therefore prone to experience leg problems. Environmental enrichment that facilitates intrinsically motivated behaviours can potentially promote activity and reduce leg problems, thereby improving broiler welfare. A...

Kobek-Kjeldager, C., Moustsen, V. A., Theil, P. K. et al. 2020. Effect of litter size, milk replacer and housing on behaviour and welfare related to sibling competition in litters from hyper-prolific sows. Applied Animal Behaviour Science 230, 105032.

Litter sizes where piglets are supernumerary to teats leads to the practice of fostering to nurse sows or to artificial rearing systems, which is associated with compromised welfare. An alternative strategy is to leave the...

Bernhard, J. K., Vidondo, B., Achermann, R. L. et al. 2020. Slightly and moderately lame cows in tie stalls behave differently from non-lame controls. A matched case-control study. Frontiers in Veterinary Science 7, 594825.

Lameness affects dairy cows worldwide and is usually associated with pain. Behavioral differences in lame compared to non-lame tie-stall-housed dairy cows might be less pronounced than in free-stall-housed, since the principle demands to a cow's...

Borell, E. V., Bonneau, M., Holinger, M. et al. 2020. Welfare aspects of raising entire male pigs and immunocastrates. Animals 10(11), 2140.

For a long time, scientists assumed that newborns have a severely limited sense of pain (if any). However, this assumption is wrong and led to a “start of the exit” from piglet surgical castration. Some...

Contreras-Aguilar, M. D., Vallejo-Mateo, P. J., Želvytė, R. et al. 2020. Changes in saliva analytes associated with lameness in cows: A pilot study. Animals 10(11), 2078.

The possible changes in a panel of 21 salivary analytes on a population of cows with lameness before and after treating lameness by hoof trimming were analyzed. Then, the analytes that showed significant changes were...