Laboratory Animals - June Issue - 256

256

Laboratory Animals 53(3)

result in the modiﬁcation of the microbiota.
Clearly, such variation in diet is not a feature of
laboratory animal studies, though their diet can obviously be experimentally manipulated. Understanding
the dynamic aspects of the biology of the microbiota
(and perhaps temporally changing the heritability of
aspects of the microbiota too) would appear to be
best achieved by studying these phenomena in wild,
rather than laboratory animals.

Declaration of Conflicting Interests

Measuring the microbiota

ORCID iD

Sequence-based characterisation of the microbiota enumerates operational taxonomic units (OTU), from
which the relative proportions of diﬀerent taxa are
calculated, so quantifying the microbiota diversity.
Recent work in humans casts doubt on the validity of
this approach.37 Speciﬁcally, a comparison of people
shows that they diﬀer very signiﬁcantly in the number
of bacteria they have in their gut microbiota.
Accounting for this when describing the bacterial taxa
present (so-called 'quantitative microbiome proﬁling'
(QMP)) shows that individuals diﬀer quantitatively in
their bacterial microbiome diversity.37 Critically, this
QMP approach gives very diﬀerent answers than the
standard proportional approach. Cleary these results
are relevant to studies in laboratory and wild animals,
though this now needs to be studied in these systems
directly. This is also directly relevant to the immunological interface between the microbiota and the host,
given that the host immune response may play a critical
role in controlling both the number and the type of
bacteria present in a host's gut.

Summary
Fundamental to the approach of using laboratory animals to understand biological phenomena is allowing
the variable under investigation to be manipulated
while all other sources of variation are minimised.
With this perspective, the genotypic and phenotypic
heterogeneity within wild animal populations would
seem an unhelpful situation. In fact, this heterogeneity
is a powerful research opportunity that can be
exploited to rigorously explore microbiota biology
and the eﬀects of it on its host. Critically, by studying
heterogeneous wild systems, the results are directly
relevant to real-world settings rather than being
models which can clearly diverge from that which
they aim to model.
Study of wild rodents' gut microbiota is still in its
infancy, but this ﬁeld must rapidly mature to validate,
or not, the utility of studies that use laboratory animals
to seek an understanding of the important eﬀects that
the gut microbiota has in animal biology.

The author(s) declares no potential conﬂicts of interest with
respect to the authorship and/or publication of this article.

Funding
The author(s) disclosed receipt of the following ﬁnancial support for the research, authorship, and/or publication of this
article: This work was supported by NERC.

Mark Viney

http://orcid.org/0000-0002-4857-1238

References
1. Ericsson AC, Gagliadri J, Bouhan D, et al. The influence
of caging, bedding, and diet on the composition of the
microbiota in different regions of the mouse gut. Sci Rep
2018; 8: 4065.
2. Ericsson AC, Davis JW, Spollen W, et al. Effects of
vendor and genetic background on the composition of
the fecal microbiota of inbred mice. PLoS One 2015;
10: e0116704.
3. Abolins S, King E, Lazarou L, et al. The comparative
immunology of wild and laboratory mice Mus musculus
domesticus. Nat. Commun 2017; 8: 14811.
4. Viney ME and Riley EM. The immunology of wild
rodents: current status and future prospects. Front.
Immunol 2017; 8: 1481.
5. Linnenbrink M, Wang J, Mardouin EA, et al. The role of
biogeography in shaping diversity of the intestinal microbiota in house mice. Mol. Ecol 2013; 22: 1904-1916.
6. Weldon L, Abolins S, Lenzi L, et al. The gut microbiota
of wild mice. PLoS One 2015; 10: e0134643.
7. Williams SH, Che X, Paulick A, et al. New York City
house mice (Mus musculus) as potential reservoirs for
pathogenic bacteria and antimicrobial resistance determinants. mBio 2018; 9: e00624-18.
8. Suzuki TA and Nacman MW. Spatial heterogeneity of
gut microbial composition along the gastrointestinal
tract in natural populations of house mice. PLoS One
2016; 11: e0163720.
9. Kohl KD, Miller AW, Marvin JE, et al.
Herbivorous rodents (Neotoma spp.) harbour abundant
and active foregut microbiota. Environ. Microbio 2014;
16: 2869-2878.
10. Kreisinger J, Cˇı´ zˇkova´ D, Voha´nka J, et al.
Gastrointestinal microbiota of wild and inbred individuals of two house mouse subspecies assessed using highthroughput parallel pyrosequencing. Microb. Ecol 2014;
23: 5048-5060.
11. Wang J, Kalyan S, Stecj N, et al. Analysis of intestinal
microbiota in hybrid house mice reveals evolutionary
divergence in a vertebrate hologenome. Nat. Commun
2015; 6: 6440.
12. Kohl KD and Dearing MD. Wild-caught rodents retain a
majority of their natural gut microbiota upon entrance
into captivity. Environ. Microbiol 2014; 6: 191-195.

http://www.orcid.org/0000-0002-4857-1238 http://www.orcid.org/0000-0002-4857-1238

Laboratory Animals - June Issue

Table of Contents for the Digital Edition of Laboratory Animals - June Issue