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. 
Çavuşoğlu, E., Rault, J.-L., Gates, R. et al. 2020. Behavioral response of weaned pigs during gas euthanasia with CO2, CO2 with butorphanol, or nitrous oxide. Animals 10(5), 787.

The swine industry is often forced to euthanize pigs in the first few weeks of life due to injuries, hernias, or unthriftiness. The majority of pigs are euthanized using carbon dioxide (CO2) gas asphyxiation but...

Watson, H. A study into viable wooden enrichment objects for Syrian hamsters. Animal Technology and Welfare 19(1), 86-88.

Failing to provide hamsters with a method to wear down their teeth can lead to detrimental behaviour such as bar chewing, and health issues, for example, overgrown teeth and tooth loss. However, hamsters use their...

Kauselmann, K., Krause, E. T., Glitz, B. et al. 2020. Short-term choice of fattening pigs for additional plant-based materials. Applied Animal Behaviour Science 226, 104975.

A major problem in conventional pig production systems is the occurrence of abnormal behaviours such as tail biting. Tail biting is a multifactorial problem, but it seems that a lack of proper enrichment materials prevents...

Hagemeister, K., Ernst, L., Kadaba Srinivasan, P. et al. 2020. Severity assessment in pigs after partial liver resection: Evaluation of a score sheet. Laboratory Animals 54(3), 251–260.

Severity assessment in biomedical research is required by the European authorities. Therefore, a variety of score sheets are available. The first score sheets were designed and introduced by Morton and Griffith (M&G) in 1985, to...

Chu, D. 2020. Malawi cichlids: A colorful 4th R story. Laboratory Animal Science Professional 8(3) (May/June), 24-25.

This article describes the successful rehoming of 60 Malawi cichlids from a vivarium at Stanford University to San Diego Zoo and the California Academy of Sciences.

Saller, A. M., Werner, J., Reiser, J. et al. 2020. Local anesthesia in piglets undergoing castration—A comparative study to investigate the analgesic effects of four local anesthetics on the basis of acute physiological responses and limb movements. PLOS ONE 15(7): e0236742.

Surgical castration of male piglets without analgesia is a painful procedure. This prospective, randomized and double-blinded study aimed to evaluate the analgesic effects of four different local anesthetics for piglet castration during the first week...

Arechavala-Lopez, P., Caballero-Froilán, J. C., Jiménez-García, M. et al. 2020. Enriched environments enhance cognition, exploratory behaviour and brain physiological functions of Sparus aurata. Scientific Reports 10, 11252.

Environmental enrichment is considered as a recommended tool to guarantee or improve the welfare of captive fish. This study demonstrates for the first time that structural environmental enrichment enhances cognition, exploratory behaviour and brain physiological...

Matrai, E., Ng, A. K. W., Chan, M. M. H. et al. 2020. Testing use of a potential cognitive enrichment device by an Indo‐Pacific bottlenose dolphin (Tursiops aduncus). Zoo Biology 39(3), 156–167.

Cognitive enrichment aims to provide animals with opportunities to use their cognitive skills and to promote behaviors associated with positive wellbeing. Cooperation in mammals has been recorded during various behavioral contexts such as hunting, mating...

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...

Luo, L., Reimert, I., Middelkoop, A. et al. 2020. Effects of early and current environmental enrichment on behavior and growth in pigs. Frontiers in Veterinary Science 7, 268.

Enriched environments are known to beneficially affect the behavior of pigs, as compared with barren pens. The influence of enrichment may, however, depend on pigs' early life housing experiences. The aim of this study was...

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...

Lauderdale, L. K., Miller, L. J. 2020. Efficacy of an interactive apparatus as environmental enrichment for common bottlenose dolphins (Tursiops truncatus). Animal Welfare 29(4), 379-386.

Environmental enrichment is a key component in improving the psychological and physiological well-being of animals under professional care. Environmental enrichment involves the addition of stimuli, including objects and cognitive challenges, into the environment in order...

Shomer, N. H., Allen-Worthington, K. H., Hickman, D. L. et al. 2020. Review of rodent euthanasia methods. JAALAS 59(3), 242–253.

The optimal choice of euthanasia method for laboratory rodents depends on a number of factors, including the scientific goals of the study, the need to minimize animal pain and/or distress, applicable guidelines and laws, the...

Thoré, E. S. J., Brendonck, L., Pinceel, T. 2020. Conspecific density and environmental complexity impact behaviour of turquoise killifish (Nothobranchius furzeri). Fish Biology 97(5), 1448–1461.

Fish models are essential for research in many biological and medical disciplines. With a typical lifespan of only 6 months, the turquoise killifish (Nothobranchius furzeri) was recently established as a time- and cost-efficient model to...

Rydén, A., Manell, E., Biglarnia, A. et al. 2020. Nursing and training of pigs used in renal transplantation studies. Laboratory Animals 54(5), 469-478.

The pig is commonly used in renal transplantation studies since the porcine kidney resembles the human kidney. To meet the requirements of intense caretaking and examination without stress, a 2-week socialisation and training programme was...

Chou, J., O’Driscoll, K., Sandercock, D. A. et al. 2020. Can increased dietary fibre level and a single enrichment device reduce the risk of tail biting in undocked growing-finishing pigs in fully slatted systems? PLOS ONE 15(10), e0241619.

This study evaluated the effectiveness of combined dietary and enrichment strategies to manage tail biting in pigs with intact tails in a conventional fully-slatted floor housing system. A 2 × 2 × 2 factorial design...

Ko, H., Chong, Q., Escribano, D. et al. 2020. Pre-weaning socialization and environmental enrichment affect life-long response to regrouping in commercially-reared pigs. Applied Animal Behaviour Science 229, 105044.

Weaning and other regrouping events as routine work in commercial farms cause stress to pigs and compromise their welfare. Several studies found positive outcomes to mitigate weaning stress when piglets were socialized (i.e. co-mingled) or...

Ocepek, M., Goold, C. M., Busančić, M. et al. 2020. Maize silage as enrichment material improves the welfare of growing-finishing pigs in environmentally-friendly pens. Applied Animal Behaviour Science 230, 105043.

Provision of enrichment in welfare- and environmentally-friendly pig pens is important for sustainable pig production. The primary aim of the present experiment was to investigate the effects of maize silage as a singular enrichment compared...

Ocepek, M., Newberry, R. C., Andersen, I. L. 2020. Which types of rooting material give weaner pigs most pleasure? Applied Animal Behaviour Science 231, 105070.

Provision of rooting material as enrichment for pigs has been primarily oriented towards reducing negative affect (suffering). Information is also needed on the impact of different types of rooting materials in promoting positive affect (pleasure)...

Rault, J.-L., Lai, A., Hemsworth, L. et al. 2020. Wireless ‘under the skull’ epidural EEG and behavior in piglets during nitrous oxide or carbon dioxide gas euthanasia. Physiology & Behavior 227, 113142.

Consciousness is central to animal welfare concerns. Its assessment is most often conducted based on behavior, with a poor understanding of the correspondence between behavior and the neurobiological processes that underlie the subjective experience of...

Telkanranta, H., Valros, A. 2020. Pigs with but not without access to pieces of recently harvested wood show reduced pen-mate manipulation after a provision of feed and straw. Applied Animal Behaviour Science 232, 105103.

In barren environments of commercial farms, pig often redirect their rooting and chewing behaviours at other pigs, which can lead to tail biting. When materials such as straw are provided, the quantity is usually too...

Arruda, A. G., Beyene, T. J., Kieffer, J. et al. 2020. A systematic literature review on depopulation methods for swine. Animals 10(11), 2161.

Swine mass depopulation refers to the destruction of large numbers of pigs and may include not only animals affected with a disease but also healthy pigs in a facility or surrounding areas. Emerging applications of...

Chou, J.-Y., Sandercock, D. A., D'Eath, R. B. et al. 2020. A High Enrichment replenishment rate reduces damaging behaviors and increases growth rate in undocked pigs kept in fully slatted pens. Frontiers in Veterinary Science 7, 584706.

One of the difficulties in complying with the prohibition of routine tail docking is a lack of effective alternative solutions to prevent tail biting, especially in fully slatted systems. This study compared three slat-compatible enrichment...

Fanning, L., Larsen, H., Taylor, P. S. 2020. A preliminary study investigating the impact of musical concerts on the behavior of captive Fiordland penguins (Eudyptes pachyrhynchus) and collared peccaries (Pecari tajacu). Animals 10(11), 2035.

Captive animal welfare is important for establishments that exhibit species for education, conservation, and research. However, captive animals are often exposed to a number of potential stressors, such as visitors and anthropogenic noise. We aimed...