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. 
Kalies, A., Baumgartner, J., Beyerbach, M. et al. 2021. Interactive rooting towers and behavioural observations as strategies to reduce tail biting on conventional pig fattening farms. Animals 11(11), 3025.

Eight pens (25 pigs/pen; n = 200) provided with an interactive straw-filled rooting tower (experimental group) and five pens (25 pigs/pen; n = 125) with a stationary (fixed) tower without straw (control group) were compared...

de Jong, I. C., Blaauw, X. E., van der Eijk, J. E. J. et al. 2021. Providing environmental enrichments affects activity and performance, but not leg health in fast- and slower-growing broiler chickens. Applied Animal Behaviour Science 241, 105375.

Effects of environmental enrichment on activity, behaviour, walking ability, contact dermatitis and performance were investigated in fast- and slower-growing broiler chickens. A total of 840 day-old male broilers, 420 of a fast-growing strain (Ross 308)...

Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

Sirovnik, J., Euteneuer, P., König von Borstel, U. 2021. An attempt to use sound-imprinting to attract broilers onto elevated platforms for night-time roosting. Applied Animal Behaviour Science 243, 105448.

Welfare of fast growing broilers is often compromised due to leg health issues. A more complex environment such as the provision of elevated platforms facilitates activity and improves leg health in fast growing broilers. Thus...

Fynn, M., Crow, G., Connor, L. 2021. Pre-farrow enrichment with burlap sheet: potential benefit for sow performance. Canadian Journal of Animal Science 101(4), 781-787.

Burlap has been proposed as an enrichment option for the conventional farrowing crate environment. Our objectives were to determine if burlap sheets hung in farrowing crates were used by sows and piglets and had any...

Campbell, D. L. M., Lee, C. 2021. A perspective on strategic enrichment for brain development: Is this the key to animal happiness? Frontiers in Veterinary Science 8, 720422.

Livestock animals are sentient beings with cognitive and emotional capacities and their brain development, similar to humans and other animal species, is affected by their surrounding environmental conditions. Current intensive production systems, through the restrictions...

Dalmau, A., Sánchez-Matamoros, A., Molina, J. M. et al. 2021. Intramuscular vs. intradermic needle-free vaccination in piglets: Relevance for animal welfare based on an aversion learning test and vocalizations. Frontiers in Veterinary Science 8, 715260.

The aim of the present study was to compare intramuscular injection with a needle and intradermic needle-free vaccinations against porcine reproductive and respiratory syndrome (PRRS) in piglets at 28 days old by studying behavioral and...

Schodl, K., Wiesauer, L., Winckler, C. et al. 2021. Reduced stocking density and provision of straw in a rack improve pig welfare on commercial fattening farms. Frontiers in Veterinary Science 8, 656211.

The aim of this study was to investigate the impact of reduced stocking density in combination with provision of additional enrichment material on pig welfare on-farm. On three growing-finishing farms in Austria, in total 974...

Vinícius dos Santos, J., de Souza Farias, S., Pereira, T. L. et al. 2021. Preference for and maintenance of interest in suspended enrichment toys in confined growing pigs. Journal of Veterinary Behavior 45, 68-73.

The objective of the present study was to evaluate the preference for, interest in, and behavior of growing pigs provided with three different suspended enrichment toys in a four-compartment environmental preference chamber (EPC). Sixty pigs...

Thomson, A. J. C., Bannister, C. C., Marshall, R. T. et al. 2021. Interest in coloured objects and behavioural budgets of individual captive freshwater turtles. Journal of Zoo and Aquarium Research, 9(4), 218-227.

Recent studies showed that freshwater turtles display inter-individual differences in various behavioural traits, which may influence their health and welfare in captivity due to differences in response to husbandry and enrichment strategies and in ability...

Monreal-Pawlowsky, T., Vaicekauskaitė , R., Palencia Membrive, G. et al. 2021. Goal-oriented behavioural and environmental enrichment in aquarium species. Journal of Zoo and Aquarium Research, 9(4), 273-280.

Environmental enrichment is a common tool used in zoo and aquarium settings to provide mental and physical stimulation to animals under human care. This paper aims to present a primary approach to goal-oriented environmental and...

Lambert, K. 2021. DIY: Acacia gum hanging saucer. Laboratory Animal Science Professional 9(5) (September/October), 50.

This article describes the ingredients, supplies, and directions to make this DIY hanging item, which is great for NHP and swine.

Merley, A. L., Duke Boynton, F. D. 2021. Design and construction of a low-cost mirror for enrichment of socially isolated pigs. Laboratory Animal Science Professional 9(5) (September/October), 56-57.

Due to their social needs, every effort should be made to house pigs with compatible conspecifics; however, there may be instances where due to experimental or veterinary concerns, single housing is necessary. In those situations...

Lambert, K. 2021. DIY: Busy boxes. Laboratory Animal Science Professional 9(6) (November/December), 32.

This article describes the ingredients and directions to make this simple DIY destructible enrichment for NHP and swine.

Lourenço da Silva, M. I., Almeida Paz, I., Chaves, G. et al. 2021. Behaviour and animal welfare indicators of broiler chickens housed in an enriched environment. PLOS ONE 16(9), e0256963.

The present study aimed to assess the influence of adding straw bales, step platforms, and laser projectors as environmental enrichment resources on the behaviour and welfare indicators of broiler chickens (Gallus gallus domesticus). A sample...

Vining, A. Q., Nunn, C. L., Samson, D. R. 2021. Enriched sleep environments lengthen lemur sleep duration. PLOS ONE 16(11), e0253251.

Characteristics of the sleep-site are thought to influence the quality and duration of primate sleep, yet only a handful of studies have investigated these links experimentally. Using actigraphy and infrared videography, we quantified sleep in...

Janhunen, M., Piironen, J., Vainikka, A. et al. 2021. The effects of environmental enrichment on hatchery-performance, smolt migration and capture rates in landlocked Atlantic salmon. PLOS ONE 16(12), e0260944.

Enrichment of rearing environment with natural elements has been suggested to improve the welfare and post-release survival of cultured fish. We studied the combined effects of shelter structures, periodical water flow and water level changes...

Kanghae, H., Thongprajukaew, K., Inphrom, S. et al. 2021. Enrichment devices for green turtles (Chelonia mydas) reared in captivity programs. Zoo Biology 40(5), 407-416.

Environmental enrichment supports the well-being and welfare of captive animals. In the current study, the most suitable form of enrichment device for captive green turtles (Chelonia mydas) was investigated, to support head-start programs rearing turtles...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Environmental complexity positively impacts affective states of broiler chickens. Scientific Reports 11(1), 16966.

Affective state can bias an animal’s judgement. Animals in positive affective states can interpret ambiguous cues more positively (“optimistically”) than animals in negative affective states. Thus, judgement bias tests can determine an animal’s affective state...

Misra, S., Bokkers, E., Upton, J. et al. 2021. Effect of environmental enrichment and group size on the water use and waste in grower-finisher pigs. Scientific Reports 11(1), 16380.

The grower-finisher stage accounts for 64% of the total on-farm herd water use. Part of this is consumed by the pigs, but a part is also wasted. Drinking water usage and wastage is affected by...

Wood, B., Rufener, C., Makagon, M. M. et al. 2021. The utility of scatter feeding as enrichment: Do broiler chickens engage with scatter–fed items? Animals 11(12), 3478.

In recent years, welfare certification companies have encouraged the use of scatter feeding as enrichment material, though there is little scientific evidence to support a scatter feeding program. This study aimed to understand the impact...

Ciborowska, P., Michalczuk, M., Bień, D. 2021. The effect of music on livestock: Cattle, poultry and pigs. Animals 11(12), 3572.

The welfare of animals, especially those kept in intensive production systems, is a priority for modern agriculture. This stems from the desire to keep animals healthy, to obtain a good-quality final product, and to meet...

Güz, B. C., de Jong, I. C., Da Silva, C. S. et al. 2021 Effects of pen enrichment on leg health of fast and slower-growing broiler chickens. PLOS ONE 16(12), e0254462.

Pen enrichment for broiler chickens is one of the potential strategies to stimulate locomotion and consequently contribute to better leg health and welfare. This study was designed to evaluate effects of using a plethora of...

Laméris, D. W., Verspeek, J., Depoortere, A. et al. 2021. Effects of enclosure and environmental enrichment on the behaviour of ring-tailed lemurs (Lemur catta). Journal of Zoological and Botanical Gardens 2(2), 164–173.

Environmental enrichment is widely used to improve the quality of life of animals under human care. To successfully implement enrichment programs, it is important to evaluate their effect in different enclosure types since housing conditions...

Waterman, J. O., McNally, R., Harrold, D. et al. 2021. Evaluating environmental enrichment methods in three zoo-housed varanidae lizard species. Journal of Zoological and Botanical Gardens 2(4), 716–727.

Environmental enrichment has been shown to enhance the behavioural repertoire and reduce the occurrence of abnormal behaviours, particularly in zoo-housed mammals. However, evidence of its effectiveness in reptiles is lacking. Previously, it was believed that...