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. 
Guijarro, A., Mauri, S., Aviles, C. et al. 2020. Effects of two CO2 stunning methods on the efficacy of stunning and blood stress indicators of turkeys under commercial processing conditions. Journal of Applied Animal Welfare Science 23(2), 231-243.

The effect of CO2 gas-stunning methods (G1: 30% CO2 15 sec, 55% CO2 40 sec, 70% CO2 45 sec; G2: 30% CO2 15 sec, 80% CO2 85 sec) on the efficacy of stunning, blood stress...

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...

Friedrich, L., Krieter, J., Kemper, N. et al. 2020. Frothy saliva—A novel indicator to assess stereotypies in sows? Applied Animal Behaviour Science 222, 104897.

The present study aimed at introducing a reliable and more feasible indicator to evaluate stereotypies in sows in comparison with the ‘Welfare Quality® animal welfare assessment protocol for sows and piglets’. Therefore, the indicators for...

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...

Park, R. M., Schubach, K. M., Cooke, R. F. et al. 2020. Impact of a cattle brush on feedlot steer behavior, productivity and stress physiology. Applied Animal Behaviour Science 228, 104995.

The aim of the present study was to investigate the impact of environmental enrichment (EE), in the form of a cattle brush, on feedlot cattle behavior, productivity and stress physiology. Steers were blocked by weight...

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...

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...

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...

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...

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...

Wilder, T., Krieter, J., Kemper, N. et al. 2020. Tail-directed behaviour in pigs – relation to tail posture and tail lesion. Applied Animal Behaviour Science 233, 105151.

Tail-biting in pigs affects the health and welfare of the animals. Different indicators, such as the tail posture, can be used to detect tail-biting at an early stage. The aim of this study was to...

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...

Camerlink, I., Chou, J.-Y., Turner, S. P. 2020. Intra-group lethal gang aggression in domestic pigs (Sus scrofa domesticus). Animals 10(8), 1287.

Intraspecific coalitional aggression is rare among all species, especially within stable social groups. We report here numerous cases of intraspecific lethal gang aggression within stable groups of domestic pigs. The objective was to describe this...

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...

Cohen, S., Kwok, M., Huang, J. 2020. Humane euthanasia of guinea pigs (Cavia porcellus) with a penetrating spring-loaded captive bolt. Animals 10(8), 1356.

Guinea pigs (Cavia porcellus) have been used in research since the 19th century to collect data due to their physiological similarities to humans. Today, animals perform a vital role in experiments and concerns for laboratory...

Gent, T. C., Gebhardt-Henrich, S., Schild, S.-L. A. et al. 2020. Evaluation of poultry stunning with low atmospheric pressure, carbon dioxide or nitrogen using a single aversion testing paradigm. Animals 10(8), 1308.

Low atmospheric pressure stunning (LAPS) has been suggested for use in poultry under 4 kg in the abattoir as a more humane alternative to carbon dioxide (CO2). However, there are currently no studies offering a...

Jung, L., Brenninkmeyer, C., Niebuhr, K. et al. 2020. Husbandry conditions and welfare outcomes in organic egg production in eight European countries. Animals 10(11), 2102.

In the European research project HealthyHens, welfare indicators as well as husbandry and management conditions were recorded in 107 organic laying hen farms in eight countries. Farms were visited at peak and end of lay...

de Castro Travnik, I., de Souza Machado, D., de Silva Gonçalves, L. et al. 2020. Temperament in domestic cats: A review of proximate mechanisms, methods of assessment, its effects on human—cat relationships, and one welfare. Animals 10(9), 1516.

Temperament can be defined as interindividual differences in behavior that are stable over time and in different contexts. The terms ‘personality’, ‘coping styles’, and ‘behavioral syndromes’ have also been used to describe these interindividual differences...

Atkinson, S., Algers, B., Pallisera, J. et al. 2020. Animal welfare and meat quality assessment in gas stunning during commercial slaughter of pigs using hypercapnic-hypoxia (20% CO2 2% O2) compared to acute hypercapnia (90% CO2 in Air). Animals 10(12), 2440.

This study assessed aversion, stunning effectiveness, and product quality of nitrogen and carbon dioxide (CO2) mixtures used for stunning pigs. A total of 1852 slaughter pigs divided into two similar batches was assessed during routine...

Schreiter, R., Damme, K., Freick, M. 2020. Edible environmental enrichments in littered housing systems: Do their effects on integument condition differ between commercial laying hen strains? Animals 10(12), 2434.

The aim of this study was to investigate the effect of additional enrichment materials (EMs; pecking stones and alfalfa bales) on the occurrence of plumage damage, skin injuries, and toe injuries, with an emphasis on...

Wotton, S., Grist, A., O’Callaghan, M. et al. 2020. Head-only stunning of turkeys Part 1: The minimum voltage necessary to break down the inherent high resistance. Animals 10(12), 2427.

Pre-slaughter stunning is required for humane slaughter. For turkeys, head-only electrical stunning is most often used by small scale producers. To ensure immediate and effective stunning, the impedance (resistance) of the tissue of the head...

Lindahl, C., Sindhøj, E., Brattlund Hellgren, R. et al. 2020. Responses of pigs to stunning with nitrogen filled high-expansion foam. Animals 10(12), 2210.

Nitrogen gas (N2) delivered in high expansion foam in a closed container could be a feasible method for humanely stunning pigs. This study aimed to evaluate potential aversion in pigs to the N2 foam method...

Jacobs, L., Bourassa, D. V., Harris, C. E. et al. 2019. Euthanasia: Manual versus mechanical cervical dislocation for broilers. Animals 9(2), 47.

The aim was to assess the onset of brain stem death for two euthanasia methods—manual cervical dislocation (CD) versus the Koechner Euthanizing Device (KED). Over three days broilers of 36 (n = 60), 42 (n...