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. 
Rørvang, M. V., Blad, M., Lindahl, C. et al. 2024. An added aroma changes the behaviour of domestic pigs in a novel situation aimed for stunning. Applied Animal Behaviour Science 270, 106145.

The currently most widespread stunning method for pigs is high concentration of carbon dioxide (CO2), but this method is under scrutiny due to animal welfare deficits. One alternative method currently under development with potential to...

Alig, B. N., Ferket, P. R., Malheiros, R. D. et al. 2023. The effect of housing environment on commercial brown egg layer production, USDA grade and USDA size distribution. Animals 13(4), 694

Consumer demand for retail cage-free eggs is driving the layer industry towards greater use of extensive housing environments. However, there is limited research on how these environments affect egg production characteristics of brown egg layers...

da Silva, M. I. L., Paz, I. C. de L. A., Jacinto, A. S. et al. 2023. Providing environmental enrichments can reduce subclinical spondylolisthesis prevalence without affecting performance in broiler chickens. PLOS ONE 18(4), e0284087.

Environmental enrichment can increase the occurrence of natural behavior and improve leg health and other animal welfare outcomes in broiler chickens. This study aimed to assess the effects of three environmental enrichments, specifically hay bales...

Evans, L., Brooks, G. C., Anderson, M. G. et al. 2023. Environmental complexity and reduced stocking density promote positive behavioral outcomes in broiler chickens. Animals 13(13), 2074.

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD)...

Foris, B., Sadrzadeh, N., Krahn, J. et al. 2023. The effect of placement and group size on the use of an automated brush by groups of lactating dairy cattle. Animals 13(4), 760.

Mechanical brushes are often provided on dairy farms to facilitate grooming. However, current brush designs do not provide data on their use, and thus little is known about the effects of group size and placement...

Kumar, P., Abubakar, A. A., Imlan, J. C. et al. 2023. Importance of knife sharpness during slaughter: Shariah and Kosher perspective and scientific validation. Animals 13(11), 1751.

Halal and kosher slaughter have given the utmost importance to the sharpness of knives during the slaughter of animals. A sharp knife of appropriate dimension (blade length) makes slaughter less painful during neck severance and...

Palermo Mendes, J., Ribeiro Caldara, F., de Castro Burbarelli, M. F. et al. 2023. Performance and welfare of sows exposed to auditory environmental enrichment in mixed or collective housing systems. Animals 13(7), 1226.

The research aimed to assess the effects of auditory environmental enrichment on sows in mixed housing (caged until 35 days after insemination and then collective pens) or collective housing (caged until 72 h after insemination...

Pereira, E., Nääs, I. de A., Ivale, A. H. et al. 2023. Energy assessment from broiler chicks’ vocalization might help improve welfare and production. Animals 13(1), 15.

Vocalization seems to be a viable source of signal for assessing broiler welfare. However, it may require an understanding of the birds’ signals, both quantitatively and qualitatively. The delivery of calls with a specific set...

Rørvang, M. V., Schild, S.-L. A., Stenfelt, J. et al. 2023. Odor exploration behavior of the domestic pig (Sus scrofa) as indicator of enriching properties of odors. Frontiers in Behavioral Neuroscience 17, 1173298.

Although the sense of smell in pigs is widely recognized as being highly developed, surprisingly little is known about their sensory ability. This study aimed to (a) identify which non-social odors pigs were able to...

Russell, A. L., Randall, L. V., Kaler, J. et al. 2023. Use of qualitative behavioural assessment to investigate affective states of housed dairy cows under different environmental conditions. Frontiers in Veterinary Science 10, 1099170.

In addition to the reduction of suboptimal welfare, there is now a need to provide farmed animals with positive opportunities to provide confidence that they have experienced a life worth living. Diversification of the environment...

Skånberg, L., Newberry, R. C., Estevez, I. et al. 2023. Environmental change or choice during early rearing improves behavioural adaptability in laying hen chicks. Scientific Reports 13(1), 6178.

Laying hens are typically moved to a novel environment after rearing, requiring adaptability to cope with change. We hypothesized that the standard rearing of laying hen chicks, in non-changing environments with limited choices (a single...

Söderquist, A., Wallenbeck, A., Lindahl, C. 2023. Social support in a novel situation aimed for stunning and euthanasia of pigs may be increased by familiar pigs—A behavioural study with weaners. Animals 13(3), 481.

The common method of stunning pigs using high concentration carbon dioxide prior to slaughter poses an animal welfare issue, as the gas is aversive. Proof of concept for using nitrogen gas encapsulated in high-expansion foam...

Alvarez-Hernandez, N., Vallejo-Timarán, D., de Jesús Rodriguez, B. 2023. Adapted original music as an environmental enrichment in an intensive pig production system reduced aggression in weaned pigs during regrouping. Animals 13(23), 3599.

In intensive swine production systems,, the practice of regrouping unfamiliar pigs is common, often leading to aggressive behavior. Although the effect of different musical genres composed for humans has been evaluated in pigs to mitigate...

dos Santos Lemes Lechuga, K. K., Caldara, F. R., de Castro Burbarelli, M. F. et al. 2023. Music and tactile stimuli during daily milking affect the welfare and productivity of dairy cows. Animals 13(23), 3671.

The objective of this study was to evaluate the effects of tactile stimuli and music during daily milking on the productive, physiological, well-being, and health parameters of dairy cows. The experiment, which lasted 39 days...

Ferreira, M. F., Fàbrega, E., Pires, I. et al. 2023. Agonic aspiration of blood: Not useful as an animal-based indicator of electrical stunning ineffectiveness in pigs (Sus scrofa domesticus). Animals 13(14), 2292.

Agonic aspiration of blood (AAB) may result from an inadequate exsanguination with accidental trachea severing, that can be favoured by ineffective stunning of pigs (Sus scrofa domesticus). This study aimed to evaluate AAB as an...

Grandin, T. 2023. A practical approach to providing environmental enrichment to pigs and broiler chickens housed in intensive systems. Animals 13(14), 2372.

In Europe, regulations contain guidance to maintain high standards of animal welfare. In many parts of the world, large buyers for supermarkets or restaurants are the main enforcers of basic animal welfare standards. They can...

Hognestad, B. W., Digranes, N., Opsund, V. G. et al. 2023. CO2 stunning in pigs: Physiological deviations at onset of excitatory behaviour. Animals 13(14), 2387.

Stunning by carbon dioxide (CO2) inhalation is controversial because it is associated with vigorous movements and behaviours which may or may not be conscious reactions. Furthermore, it is unknown whether some behaviours might indicate the...

Olczak, K., Penar, W., Nowicki, J. et al. 2023. The role of sound in livestock farming—Selected aspects. Animals 13(14), 2307.

To ensure the optimal living conditions of farm animals, it is essential to understand how their senses work and the way in which they perceive their environment. Most animals have a different hearing range compared...

Zhao, S., Cui, W., Yin, G. et al. 2023. Effects of different auditory environments on behavior, learning ability, and fearfulness in 4-week-old laying hen chicks. Animals 13(19), 3022.

Environmental enrichment can improve animal welfare. As a method of environmental enrichment, the effect of different auditory stimulations on the behavior response and welfare of laying hen chicks has yet to be investigated. Therefore, this...

Aigueperse, N., Boyer, V., Vasseur, E. 2023. How outing conditions relate to the motivation of movement-restricted cattle to access an outdoor exercise yard. Behavioural Processes 213, 104957.

Assessing animal motivation to access a given resource is one method available to evaluate what to provide in the living environments of captive animals. Providing increased opportunities for movement can be seen as an important...

Crone, C., Caldara, F. R., Martins, R. et al. 2023. Environmental enrichment for pig welfare during transport. Journal of Applied Animal Welfare Science 26(3), 393–403.

This study aimed to assess the effects of environmental enrichment for pigs during transportation in different phases of their productive cycle. Two trials were conducted, the first during transportation of pigs from the piglet production...

Kim, J., Lee, J., Kang, K. et al. 2023. Effects of sling belt provision on behaviour, skin lesions, and salivary cortisol level in growing pigs after transport and regrouping. Applied Animal Behaviour Science 269, 106116.

The provision of enrichment material has been widely recommended to mitigate stress and minimise aggressive behaviour as well as enhance the welfare of pigs after transport and regrouping. In this study, we assessed the effects...

Rørvang, M. V., Schild, S.-L. A., Wallenbeck, A. et al. 2023. Rub ‘n’ roll – Pigs, Sus scrofa domesticus, display rubbing and rolling behaviour when exposed to odours. Applied Animal Behaviour Science 266, 106022.

Pigs are regarded as having a highly developed sense of smell, although scientific information on the topic is sparse. Here, we describe two behaviours unexpectedly observed in a study assessing pigs’ responses to odours and...

Vargas, L. B., Caldara, F. R., Lippi, I. C. de C. et al. 2023. Environmental enrichment strategies for weaned pigs: Welfare and behavior. Journal of Applied Animal Welfare Science 26(2), 205–217.

This research aims to evaluate the effects of different types and strategies of environmental enrichment for weaned pigs on behavior. Forty weaned piglets aged 21 to 28 days were distributed in a completely randomized design...

Zhao, S., Zhang, R., Li, C. et al. 2023. The effect of short-term classical music stimulus on behavior and tonic immobility reaction of pullets. Journal of Applied Animal Welfare Science 26(3), 386–392.

The purpose of this study was to investigate the effect of short-term stimulation of classical music on the behavior of pullets and to explore whether classical music as an auditory enrichment factor reduces the fear...