As in humans, the Angiotensin I Converting Enzyme 2 (ACE2) receptors of hamsters naturally permit binding of the SARS-CoV-2 virus spike protein. This suggests that hamsters are an important model for infectious disease research against this virus as infection, clinical signs of disease, transmission to conspecifics and antibody mobilization in hamsters is demonstratable1,2. As a relatively uncommon research model, they do present novel requirements when compared to more standard pre-clinical rodent models, such as mice, that do not act as natural SARS-CoV-2 hosts.
Hamsters live as solitary, wide-ranging, deep burrowing animals in nature3,4. Although bedding depth of 80cm is ideal, even providing half of this depth results in improved welfare on a variety of measures such as body condition and frequency of cage gnawing. Housing without adequate burrowing depth is known to cause stress5. As the species is very scent-dependant it is also advised to retain some housing material during regular housing cleaning to reduce the stress that occurs when they are placed into a scent novel environment6. There is some debate about whether communal housing with conspecifics (as commonly used for mice) versus the more natural condition of solitary housing can also cause stress6,7. Ideally, hamsters should be housed singly or in small numbers with a large cage of a size usually used for rats, and include plenty of nesting material and access to an exercise wheel6
As mentioned previously, hamsters have a very acute sense of smell; scent marking is an important communication tool and they can distinguish between other hamsters as well as kin from non-kin8. To reduce the impact of other hamsters or human scent on research findings, it is important that gloves are always used when handling the animals. Additionally, removal of the scent of other hamsters from conserved laboratory equipment is strongly advised. In their study, Todrank et al. addresses the confounding factor of scent between subjects with a washing with a common laboratory glassware cleaner8. After washing, items are rinsed in hot water and air-dried. This cleaning regimen is adequate to remove scents of previous hamsters from the equipment.
The vivoFlow is designed to be cleaned easily by any laboratory members, using a wide variety of common household and laboratory cleaners. Since scent is an important modality for hamsters, this easy cleaning is a key element to achieve accurate data in all rodent studies.
In addition to scent, visual cues can have an impact on the resulting data. Hamster vision is very similar to mouse vision, although species to species variation is noted. Mice have two cone types, demonstrating peak vision sensitivities at 359 nm (ultraviolet) and 511 nm (blue) wavelengths9. Siberian dwarf hamsters also have two cones and are most sensitive to wavelengths of 360 and 49 8nm. The popular Golden Syrian hamster has a single cone and responds maximally to a wavelength of approximately 506 nm10 (see Figure 1 adapted from these publications). As these animals do not see yellows, the amber tint of the vivoFlow is used to induce a feeling of safety which in turn leads to quicker acclimation times smoother breathing and more natural behaviour during data collection.
The vivoFlow is an excellent tool to monitor breathing changes that develop over time, with or without interventions such as infection, drug responses, gas or aerosol challenges. SCIREQ is committed to providing solutions for novel research at the forefront of respiratory research including this new trend of hamsters as an infectious disease model, such as COVID-19.
Contact us today to learn about how our solutions can provide detailed pulmonary insights that could enrich your next research endeavour!
1Imai et al. 2020. Syrian hamsters as a small animal model for SARS-CoV-2 infection and countermeasure development. PNAS; 117(28): 16587–16595. DOI: 10.1073/pnas.2009799117
2Sia et al. 2020. Pathogenesis and transmission of SARS-CoV-2 in golden hamsters. Nature 583, 834–838. DOI: 10.1038/s41586-020-2342-5
3Gattermann et al. 2001. Notes on the current distribution and the ecology of wild golden hamsters (Mesocricetus auratus). J. Zool., Lond.; 254: 359-365.
4Murry, M. 2012. The Hamster: Reproduction and Behavior. Chapter 1: History of the Capture and Domestication of the Syrian Golden Hamster (Mesocricetus auratus Waterhouse). Springer Publishing
5Hauzenberger et al. 2006. The influence of bedding depth on behaviour in golden hamsters (Mesocricetus auratus). Applied Animal Behaviour Science 100: 280–294. DOI:1 0.1016/j.applanim.2005.11.012
6Cunnen, M. 2015. Comfortable Quarters for Laboratory Animals; 10th ed. Liss et al.. Chapter 4: Hamsters. Animal Welfare Institute
8Todrank et al. 1998. Kin recognition in golden hamsters: evidence for kinship odours. Anim. Behav., 55: 377–386.
9Jacobs et al. 1991, J. Retinal receptors in rodents maximally sensitive to ultraviolet light. Nature 353: 655–656. DOI:10.1038/353655a0
10Calderone and Jacobs. 1999. Cone receptor variations and their functional consequences in two species of hamster. Visual Neuroscience; 16(1):53-63. DOI: 10.1017/S0952523899161029