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. 
Sen Sarma, O., Frymus, N., Axling, F. et al. 2023. Optimizing zebrafish rearing−Effects of fish density and environmental enrichment. Frontiers in Behavioral Neuroscience 17, 1204021.

Despite its popularity in research, there is very little scientifically validated knowledge about the best practices on zebrafish (Danio rerio) husbandry, which has led to several facilities having their own husbandry protocols. This study was...

Lupfer, G., Brandenburger, A., Machado, M. et al. 2023. Ultrasonic vocalizations near 30 kHz may indicate excitement rather than distress in female Wistar rats. Applied Animal Behaviour Science 261, 105881.

Rats emit ultrasonic vocalizations (USVs), sometimes referred to as 50-kHz vocalizations, during activities such as play and lower-frequency USVs, sometimes referred to as 22-kHz vocalizations, when experiencing distress. Definitions of 22-kHz vocalizations vary in terms...

Broadfoot, C. K., Lenell, C., Kelm-Nelson, C. A. et al. 2023. Effects of social isolation on 50-kHz ultrasonic vocalizations, affective state, cognition, and neurotransmitter concentrations in the ventral tegmental and locus coeruleus of adult rats. Behavioural Brain Research 437, 114157.

Vocal communication, cognition, and affective state are key features of sustained health and wellness, and because vocalizations are often socially-motivated, social experience likely plays a role in these behaviors. The monoaminergic systems of the ventral...

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...

Schnaider, M. A., Heidemann, M. S., Pescatori Silva, A. H. et al. 2022. Vocalization and other behaviors indicating pain in beef calves during the ear tagging procedure. Journal of Veterinary Behavior 47, 93-98.

Vocalization and other behavior signals are used as tools to assess animal welfare in beef calves. This paper aimed to compare vocal parameters and behavior signals expressed by beef calves submitted either to ear tagging...

Schnaider, M. A., Heidemann, M. S., Silva, A. H. P. et al. 2022. Vocalization and other behaviors as indicators of emotional valence: The case of cow-calf separation and reunion in beef cattle. Journal of Veterinary Behavior 49, 28-35.

Vocalization may communicate the emotional state in vocal animals. We aimed to describe and compare vocalization and other behavioral signs of cow-calf pairs in emotionally negative and positive situations, and the potential influence of genetic...

Tivey, E. K. L., Martin, J. E., Brown, S. M. et al. 2022. Sex differences in 50 kHz call subtypes emitted during tickling-induced playful behaviour in rats. Scientific Reports 12(1), 15323.

‘Tickling’ induces positive affective states in laboratory rats as evidenced by the production of 50-kHz ultrasonic vocalisations (USVs), although this has mostly been investigated in males. Juvenile rats emit distinctive 50-kHz USV subtypes. Frequency-modulated (FM)...

Thompson, J. S., Hudson, C. D., Huxley, J. N. et al. 2022. A randomised controlled trial to evaluate the impact of indoor living space on dairy cow production, reproduction and behaviour. Scientific Reports 12(1), 3849.

As a global society, we have a duty to provide suitable care and conditions for farmed livestock to protect animal welfare and ensure the sustainability of our food supply. The suitability and biological impacts of...

Saraiva, J. L., Rachinas-Lopes, P., Arechavala-Lopez, P. 2022. Finding the “golden stocking density”: A balance between fish welfare and farmers’ perspectives. Frontiers in Veterinary Science 9, 930221.

The effects of stocking density on fish welfare are complex and involve many interacting parameters. This complex relationship between fish welfare, stocking density and influencing factors make it challenging to define a specific optimal (“golden”)...

Laurijs, K. A., Briefer, E. F., Reimert, I. et al. 2021. Vocalisations in farm animals: A step towards positive welfare assessment. Applied Animal Behaviour Science 236, 105264.

Public concern for farm animal welfare is increasing. Animal welfare is defined as the balance of positive and negative emotions, where positive emotions are key to a good animal life. Emotion is defined as an...

Seidisarouei, M., van Gurp, S., Pranic, N. M. et al. 2021. Distinct profiles of 50 kHz vocalizations differentiate between social versus non-social reward approach and consumption. Frontiers in Behavioral Neuroscience 15, 693698.

Social animals tend to possess an elaborate vocal communication repertoire, and rats are no exception. Rats utilize ultrasonic vocalizations (USVs) to communicate information about a wide range of socially relevant cues, as well as information...

Martini, A., Huysseune, A., Witten, P. E. et al. 2021. Plasticity of the skeleton and skeletal deformities in zebrafish (Danio rerio) linked to rearing density. Journal of Fish Biology 98(4), 971-986.

The teleost zebrafish (Danio rerio), an established model for human skeletal diseases, is reared under controlled conditions with defined parameters for temperature and photoperiod. Studies aimed at defining the proper rearing density have been performed...

Andersson, M., Kettunen, P. 2021. Effects of holding density on the welfare of zebrafish: A systematic review. Zebrafish 18(5), 297-306.

The zebrafish is becoming an increasingly popular research animal around the world. Its welfare is affected by an array of environmental factors, such as food access and water quality. Holding density is an important welfare...

Park, R. M., Foster, M., Daigle, C. L. 2020. A scoping review: The impact of housing systems and environmental features on beef cattle welfare. Animals 10(4), 565.

Housing systems and environmental features can influence beef cattle welfare. To date, little information has been synthesized on this topic. The aim of this scoping review was to examine the relationship between housing and welfare...

Cortese, M., Brščić, M., Ughelini, N. et al. 2020. Effectiveness of stocking density reduction on mitigating lameness in a Charolais finishing beef cattle farm. Animals 10(7), 1147.

This study aimed at assessing whether a reduction in stocking density (SKD) would mitigate lameness and positively affect the performance and health of Charolais bulls in an Italian commercial farm. Bulls were distributed in groups...

Lutz, J., Burla, J.-B., Gygax, L. et al. 2019. Horned and dehorned dairy cows differ in the pattern of agonistic interactions investigated under different space allowances. Applied Animal Behaviour Science 218, 104819.

Limited space in dairy cattle farming is associated with frequent encounters between cows, often resulting in agonistic interactions and injuries, especially in horned cows. Previous studies with dairy cows investigated space allowances in the waiting...

Brudzynski, S. M. 2019. Emission of 22 kHz vocalizations in rats as an evolutionary equivalent of human crying: Relationship to depression. Behavioural Brain Research 363, 1-12.

There is no clear relationship between crying and depression based on human neuropsychiatric observations. This situation originates from lack of suitable animal models of human crying. In the present article, an attempt will be made...

Green, A., Clark, C., Favaro, L. et al. 2019. Vocal individuality of Holstein-Friesian cattle is maintained across putatively positive and negative farming contexts. Scientific Reports 9, 18468.

Cattle mother-offspring contact calls encode individual-identity information; however, it is unknown whether cattle are able to maintain individuality when vocalising to familiar conspecifics over other positively and negatively valenced farming contexts. Accordingly, we recorded 333...

Witaifi, A. A., Ali, A. B. A., Siegford, J. M. 2018. Stall and feed bunk stocking rates impact cows' diurnal behavior and activity in automatic milking system farms. Journal of Veterinary Behavior 24, 48-55.

High stall stocking rates have been shown to alter behavior of cows in parlor-milked systems; however, no studies have examined stocking rates for cows milked with automatic milking systems (AMSs). Therefore, we examined the influence...

Barker, T. H., George, R. P., Howarth, G. S. et al. 2017. Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare. PLOS ONE 12(9), e0185135.

Minimum space allowances for laboratory rats are legislated based on weight and stocking rates, with the understanding that increased housing density encourages crowding stress. However, there is little evidence for these recommendations, especially when considering...

Burke, C. J., Kisko, T. M., Swiftwolfe, H. et al. 2017. Specific 50-kHz vocalizations are tightly linked to particular types of behavior in juvenile rats anticipating play. PLOS ONE 12(5), e0175841.

Rat ultrasonic vocalizations have been suggested to be either a byproduct of physical movement or, in the case of 50-kHz calls, a means to communicate positive affect. Yet there are up to 14 distinct types...

Pinelli, C., Leri, F., Turner, P. 2017. Long term physiologic and behavioural effects of housing density and environmental resource provision for adult male and female Sprague Dawley rats. Animals 7(6), 44.

There is considerable interest in refining laboratory rodent environments to promote animal well-being, as well as research reproducibility. Few studies have evaluated the long term impact of enhancing rodent environments with resources and additional cagemates...

Jones, T., Robinson, M., Leach, M. et al. 2017. Ultrasonic vocalisation as a measure of positive welfare in rats. Animal Technology and Welfare 16(2), 127-129.

Studies of animal welfare in laboratory animals have historically relied on the measurement of negative indicators rather than the assessment of positive indicators of welfare. Practical methods of welfare assessment are required to allow refinement...

Mortell, D., Moores, S. 2017. Increasing survival rates in the Zebrafish (Zebra danio) at the University of Manchester. Animal Technology and Welfare 16(3), 214-215.

The average survival rate for our Zebrafish (ZF) embryos was 65%. When it was time to create our next generation of Wild Type (WT) (used for embryo production), we decided to run a trial focussing...

Kisko, T. M., Himmler, B. T., Himmler, S. M. et al. 2015. Are 50-kHz calls used as play signals in the playful interactions of rats? II. Evidence from the effects of devocalization. Behavoural Processes 111, 25-33.

During playful interactions, juvenile rats emit many 50-kHz ultrasonic vocalizations, which are associated with a positive affective state. In addition, these calls may also serve a communicative role – as play signals that promote playful...