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. 
Khonmee, J., Brown, J. L., Pérez, A. L. et al. 2023. Effect of electroejaculation protocols on semen quality and concentrations of testosterone, cortisol, malondialdehyde, and creatine kinase in captive Bengal tigers. Animals 13(12), 1893.

The Bengal tiger (Panthera tigris tigris) is critically endangered, so assisted reproductive technologies, including artificial insemination, are important conservation tools. For wild and domestic felids, electroejaculation (EE) is the most common semen collection method, with...

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...

Chakravarty, S., Donoghue, J., Waite, A. S. et al. 2023. Closed-loop control of anesthetic state in nonhuman primates. PNAS Nexus 2(10), 293.

Research in human volunteers and surgical patients has shown that unconsciousness under general anesthesia can be reliably tracked using real-time electroencephalogram processing. Hence, a closed-loop anesthesia delivery (CLAD) system that maintains precisely specified levels of...

Crawford, C., Rand, J., Rohlf, V. et al. 2023. Solutions-based approach to urban cat management—Case studies of a One Welfare approach to urban cat management. Animals 13(21), 3423.

Urban free-roaming cats create concern about their impacts on wildlife and human health, leading to the use of trap–adopt–kill methods to manage these populations. This method is ineffective at decreasing the free-roaming cat population and...

Imboden, T. J., Pownall, W. R., Rubin, S. et al. 2023. Determination of a safe sedative combination of dexmedetomidine, ketamine and butorphanol for minor procedures in dogs by use of a stepwise optimization method. Acta Veterinaria Scandinavica 65(1), 41.

In veterinary practice, most minor procedures such as radiographs, skin biopsies, and wound treatments require sedation. The combination of butorphanol, ketamine, and dexmedetomidine is commonly used, but the ideal dosages for this combination have not...

Piekarski, N., Hobbs, T. R., Jacob, D. et al. 2023. A comparison of oocyte yield between ultrasound-guided and laparoscopic oocyte retrieval in rhesus macaques. Animals 13(19), 3017.

Obtaining quality oocytes is a prerequisite for ART-based studies. Here we describe a method for transabdominal ultrasound-guided (US) oocyte retrieval in rhesus macaques (Macaca mullata) and compare it to the standard surgical approach using laparoscopy...

Rosales, C., Sands, C. 2022. Confirming sexual maturity in male cynomolgus macaques by urinary spermatozoa microscopic examination. Laboratory Animal Science Professional 10(1) (January/February), 60-61.

Medications often require studies performed in sexually mature cynomolgus macaques. At this time, there are few options available to confirm sexual maturity in male macaques. Electroejaculation and collection of seminal fluid are invasive and require...

Spitzer, H. B., Meagher, R. K., Proudfoot, K. L. 2022. The impact of providing hiding spaces to farmed animals: A scoping review. PLOS ONE 17(11), e0277665.

Many wild animals perform hiding behaviours for a variety of reasons, such as evading predators or other conspecifics. Unlike their wild counterparts, farmed animals often live in relatively barren environments without the opportunity to hide...

de Jong, I. C., Schokker, D., Gunnink, H. et al. 2022. Early life environment affects behavior, welfare, gut microbiome composition, and diversity in broiler chickens. Frontiers in Veterinary Science 9, 977359.

This study aimed to identify whether early-life conditions in broiler chickens could affect their behavior and welfare, and whether or not this was associated with an altered gut microbiome composition or diversity. Broilers were tested...

Argüelles, J., Echaniz, M., Bowen, J. et al. 2021. The impact of a stress-reducing protocol on the quality of pre-anaesthesia in cats. Veterinary Record 188(12), e138.

Introduction: Transport to the clinic is a major source of stress for cats. The process involves being put into a carrier, driven in a car and handled. Cats are therefore removed from the safe-haven of...

Guthrie, A., Strike, T., Patterson, S. et al. 2021. The past, present and future of hormonal contraceptive use in managed captive female tiger populations with a focus on the current use of deslorelin acetate. Zoo Biology 40(4), 306-319.

Tigers (Panthera tigris spp.) are endangered in the wild; ensuring sustainable insurance populations requires careful planning within zoological collections. In captive situations, contraceptives are often used to control breeding and ensure genetically viable populations that...

Penfold, L. M., Norton, T., Asa, C. S. 2021. Effects of GnRH agonists on testosterone and testosterone-stimulated parameters for contraception and aggression reduction in male lion-tailed Macaques (Macaca silenus). Zoo Biology 40(6), 541-550.

Managing social groups in zoos requires controlling reproduction in individuals that do not have a current breeding recommendation, while simultaneously maintaining social harmony and animal well-being. Contraceptives, such as gonadotropin releasing-hormone (GnRH) agonists, that suppress...

Kidd, P., Rose, P. 2021. Influences of rearing environment on behaviour and welfare of captive Chilean flamingos: A case study on foster-reared and parent-reared birds. Journal of Zoological and Botanical Gardens 2(2), 174–206.

Behaviour signals the internal states that relate to an individual’s welfare and its development is influenced by the early social environment that an animal experiences. Husbandry practices can alter this early social environment, for example...

van den Oever, A. C. M., Rodenburg, T. B., Bolhuis, J. E. et al. 2020. Relative preference for wooden nests affects nesting behaviour of broiler breeders. Applied Animal Behaviour Science 222, 104883.

Optimising nest design for broiler breeders has benefits for both the animals and the producers. The welfare of the hens will increase by providing preferred housing, while also reducing eggs laid outside the nests. These...

Arrazola, A., Mosco, E., Widowski, T. M. et al. 2020. The effect of alternative feeding strategies during rearing on the behaviour of broiler breeder pullets. Applied Animal Behaviour Science 224, 104929.

Broiler breeders are feed-restricted during rearing to avoid the negative consequences of obesity during lay due to their genetic potential for fast growth rate. Feed restriction leads to chronic hunger, frustration and lack of satiety...

Yaw, T. J., Mans, C., Johnson,S. et al. 2020. Evaluation of subcutaneous administration of alfaxalone-midazolam and dexmedetomidine-midazolam for sedation of ball pythons (Python regius). Journal of the American Veterinary Medical Association 256(5), 573-579.

OBJECTIVE: To evaluate SC administration of alfaxalone-midazolam and dexmedetomidine-midazolam for sedation of ball pythons (Python regius). ANIMALS: 12 healthy juvenile ball pythons. PROCEDURES: In a randomized crossover study, each snake was administered a combination of...

Schiffmann, C., Hård, T., Hjelm, M. et al. 2020. Soft and persistent—The influence of sand-flooring and calves on the resting behavior of a zoo-kept African elephant (Loxodonta africana) group. Zoo Biology 39(1), 56-62.

Caring for all aspects of zoo elephants’ well-being is considered a major challenge. Providing an appropriate flooring substrate to facilitate lying rest presents a meaningful part of a holistic management concept. Investigating the impact of...

Rasys, A. M., Divers, S. J., Lauderdale, J. D. et al. 2020. A systematic study of injectable anesthetic agents in the brown anole lizard (Anolis sagrei). Laboratory Animals 54(3), 281–292.

Anolis lizards have served as important research models in fields ranging from evolution and ecology to physiology and biomechanics. However, anoles are also emerging as important models for studies of embryo development and tissue regeneration...

Brown, M. E., Torkelson, M. R., Olsen, G. H. et al. 2020. Comparison of fecal glucocorticoid metabolite concentrations in hand‐ versus parent‐reared whooping cranes (Grus americana). Zoo Biology 39(4), 276–280.

Endangered whooping cranes (Grus americana ) have been produced in captivity for reintroduction programs since the 1980s, using techniques such as artificial insemination, multiple clutching, and captive‐rearing to speed recovery efforts. Chicks are often hand‐reared...

Nordquist, R. E., Zeinstra, E. C., Dougherty, A. et al. 2020. Effects of dark brooder rearing and age on hypothalamic vasotocin and feather corticosterone levels in laying hens. Frontiers in Veterinary Science 7, 19.

Chickens cannot independently thermoregulate at hatch and lack opportunity to behaviorally thermoregulate with a hen in the egg layer industry, thus barns are heated to thermoneutral temperatures. Dark brooders are low-energy-consuming hot plates, which may...

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...

Gebhardt-Henrich, S. G., Jordan, A., Toscano, M. J. et al. 2020. The effect of perches and aviary tiers on the mating behaviour of two hybrids of broiler breeders. Applied Animal Behaviour Science 233, 105145.

Broiler breeders are kept for the production of fertile eggs. They face serious welfare problems like aggressive behaviour of the males towards females during mating. Furthermore, broiler breeders are usually kept without perches which are...

Kane, L. P., Chinnadurai, S. K., Vivirito, K. et al. 2020. Comparison of isoflurane, sevoflurane, and desflurane as inhalant anesthetics in prairie rattlesnakes (Crotalus viridis). Journal of the American Veterinary Medical Association 257(9), 945-949.

OBJECTIVE: To characterize induction and recovery characteristics of 3 commonly used inhalant anesthetics in prairie rattlesnakes (Crotalus viridis): isoflurane, sevoflurane, and desflurane. ANIMALS: 12 healthy adult prairie rattlesnakes. PROCEDURES: In a randomized crossover design, snakes...

Kane, L. P., Chinnadurai, S. K., Vivirito, K. et al. 2020. Comparison of isoflurane, sevoflurane, and desflurane as inhalant anesthetics in prairie rattlesnakes (Crotalus viridis). Journal of the American Veterinary Medical Association 257(9), 945-949.

OBJECTIVE: To characterize induction and recovery characteristics of 3 commonly used inhalant anesthetics in prairie rattlesnakes (Crotalus viridis): isoflurane, sevoflurane, and desflurane. ANIMALS: 12 healthy adult prairie rattlesnakes. PROCEDURES: In a randomized crossover design, snakes...

Abayarathna, T., Webb, J. K. 2020. Effects of incubation temperatures on learning abilities of hatchling velvet geckos. Animal Cognition 23(4), 613–620.

Stressful environments in utero can have a profound influence on cognitive functions and learning ability. In lizards, thermal environments experienced by embryos can shape a range of traits, including sex, body size, and locomotor performance...