Buscar

Exotic Small Mammal Care and Husbandry

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Você viu 3, do total de 198 páginas

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Você viu 6, do total de 198 páginas

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Você viu 9, do total de 198 páginas

Faça como milhares de estudantes: teste grátis o Passei Direto

Esse e outros conteúdos desbloqueados

16 milhões de materiais de várias disciplinas

Impressão de materiais

Agora você pode testar o

Passei Direto grátis

Prévia do material em texto

Exotic Small Mammal Care 
and Husbandry
Exotic Small Mammal Care 
and Husbandry
Ron E. Banks, DVM, DACLAM, DACVPM, CPIA
Julie M. Sharp, DVM
Sonia D. Doss, M.Ed., RLATG
Deborah A. Vanderford, DVM
All authors are staff at the Offi ce of Animal Welfare Assurance, Duke University, 
Durham, North Carolina
A John Wiley & Sons, Inc., Publication
Edition fi rst published 2010
© 2010 Ron E. Banks, Julie M. Sharp, Sonia D. Doss, Deborah A. Vanderford
Blackwell Publishing was acquired by John Wiley & Sons in February 2007. Blackwell’s publishing program has 
been merged with Wiley’s global Scientifi c, Technical, and Medical business to form Wiley-Blackwell.
Editorial Offi ce
2121 State Avenue, Ames, Iowa 50014-8300, USA
For details of our global editorial offi ces, for customer services, and for information about how to apply for 
permission to reuse the copyright material in this book, please see our website at www.wiley.com/wiley-blackwell.
Authorization to photocopy items for internal or personal use, or the internal or personal use of specifi c clients, is 
granted by Blackwell Publishing, provided that the base fee is paid directly to the Copyright Clearance Center, 222 
Rosewood Drive, Danvers, MA 01923. For those organizations that have been granted a photocopy license by 
CCC, a separate system of payments has been arranged. The fee codes for users of the Transactional Reporting 
Service are ISBN-13: 978-0-8138-1022-5/2010.
Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and 
product names used in this book are trade names, service marks, trademarks or registered trademarks of their 
respective owners. The publisher is not associated with any product or vendor mentioned in this book. This 
publication is designed to provide accurate and authoritative information in regard to the subject matter covered. 
It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional 
advice or other expert assistance is required, the services of a competent professional should be sought.
Disclaimer
The contents of this work are intended to further general scientifi c research, understanding, and discussion only and 
are not intended and should not be relied upon as recommending or promoting a specifi c method, diagnosis, or 
treatment by practitioners for any particular patient. The publisher and the author make no representations or 
warranties with respect to the accuracy or completeness of the contents of this work and specifi cally disclaim all 
warranties, including without limitation any implied warranties of fi tness for a particular purpose. In view of 
ongoing research, equipment modifi cations, changes in governmental regulations, and the constant fl ow of 
information relating to the use of medicines, equipment, and devices, the reader is urged to review and evaluate the 
information provided in the package insert or instructions for each medicine, equipment, or device for, among other 
things, any changes in the instructions or indication of usage and for added warnings and precautions. Readers 
should consult with a specialist where appropriate. The fact that an organization or Website is referred to in this 
work as a citation and/or a potential source of further information does not mean that the author or the publisher 
endorses the information the organization or Website may provide or recommendations it may make. Further, 
readers should be aware that Internet Websites listed in this work may have changed or disappeared between when 
this work was written and when it is read. No warranty may be created or extended by any promotional statements 
for this work. Neither the publisher nor the author shall be liable for any damages arising herefrom.
Library of Congress Cataloging-in-Publication Data
Exotic small mammal care and husbandry / Ron E. Banks . . . [et al.].
p. ; cm.
Includes bibliographical references and index.
ISBN 978-0-8138-1022-5 (pbk. : alk. paper) 1. Exotic animals. 2. Pets. I. 
Banks, Ron E. [DNLM: 1. Animal Welfare. 2. Veterinary Medicine. 3. Animal Husbandry. 4. 
Animals, Domestic. SF 745 E96 2010]
SF413.E96 2010
636–dc22
2009041421
A catalog record for this book is available from the U.S. Library of Congress.
Set in 9.5 on 11.5 pt Sabon by Toppan Best-set Premedia Limited
Printed in Singapore
1 2010
www.wiley.com/wiley-blackwell
Contents
Acknowledgments vii
 1 Introduction 3
 2 Enrichment 11
 3 Preventive Medicine 21
 4 Rabbits 49
 5 Ferrets 61
 6 Mice 73
 7 Rats 81
 8 Gerbils 93
 9 Hamsters 103
10 Guinea pigs 115
11 Chinchillas 125
12 Degus 137
13 Hedgehogs 143
14 Sugar Gliders 157
15 Opossums 169
Index 175 
Color plate appears between pages 80 and 81 
v
 Acknowledgments 
 The authors acknowledge the many unnamed 
and on occasion unknown contributors to our 
education and training in the fi eld of husbandry 
and veterinary medicine. No accomplishment 
is a singular achievement, and without the 
assistance of many this book would not have 
been possible. Thank you. 
 It is the desire and hope of the authors that 
this text will be used for the betterment of the 
animals with which we share this globe and for 
improvement of the condition and environ-
ment in which they live. Our commitment to 
strong and effective stewardship of the condi-
tions in which we and animals live is the highest 
ideal one can assign to a human - and - animal 
relationship; the engaged manner of our com-
passionate care and our progressive husbandry 
is the best refl ection of our humaneness. 
 The authors wish to acknowledge Mr. Ian 
Thomas for all line drawing illustrations as 
well as the following individuals for assistance 
with photographs: Amy M. McArdle, CVT, 
LATG; Dan Johnson, DVM; Judi Fox, Cynthia 
Prevost, and Dorcas O ’ Rourke, DVM. 
vii
Exotic Small Mammal Care 
and Husbandry
 Introduction 1
 The role of the veterinary technician continues 
to develop and mature. Although historically 
the duties allotted to the veterinary technician 
have been supportive and responsive — that is, 
do what you are told when you are told to do 
it — the current, progressive veterinary climate 
offers increasing levels of responsibility for 
engagement. Principal to the modern veteri-
nary technician is the ability to have a dramatic 
impact on the well - being of the pet by educat-
ing the pet owner and assisting with building 
and maintaining a strong relationship of stew-
ardship and compassion of the pet owner with 
the pet. To best accomplish this task, the vet-
erinary technician must clearly understand the 
impact of a variety of factors, both intrinsic 
and extrinsic, and the role each factor may play 
in the health and well - being of the small 
mammal pet. 
 Any list of factors that affect the well - being 
of a pet would be incomplete, but to provide 
an outline for this discussion we should con-
sider those in the following list as having the 
potential to affect the pet ’ s well - being: 
 • Genetics 
 • Age 
 • Gender 
 • Immune status 
 • Circadian rhythms 
 • Endocrine system 
 • Cage design 
 • Bedding choices 
 • Cage accessories 
 • Enrichment strategies 
 • Watering options 
3
 • Feeding options 
 • Temperature 
 • Humidity 
 • Thermal neutral zones 
 • Ventilation 
 • Illumination 
 • Noise 
 • Transportation 
 • Overcrowding 
 • Isolation 
 • Social ranking 
 • Handling 
 • Chemicals used in sanitation 
 • Air quality 
 • Water intake 
 • Feeds and diets 
 • Adventitial diseases 
 The take - home questions for any discussion 
such as this are: 
 • What is the pet owner doing that may impact 
the well - being of the pet? 
 • Is theimpact of those actions improving or 
detracting from the well - being of the pet? 
 We will discuss the factors affecting the pet ’ s 
well - being by considering those which are 
 intrinsic and those which are extrinsic . 
 INTRINSIC FACTORS AFFECTING 
WELL - BEING 
 Intrinsic factors are those that are inherent to 
the animal, including genetics, age, sex, health, 
4 Exotic Small Mammal Care and Husbandry
immune function is important as neither the 
very young nor the very old can successfully 
mount a strong immune challenge to infection. 
The geriatric animal is prone to increased 
disease states as the organ systems begin to fail; 
the young animal is prone to similar concerns, 
but because of physiologic systems that are not 
fully functional at the time of birth. This is 
often species dependent: a guinea pig is “ preco-
cious ” and ready for all that life can throw at 
it, whereas a ferret requires weeks of nurturing 
and care to survive to healthy adulthood. 
 Gender 
 Gender may also mark an important considera-
tion for animal well - being. For example, 80% 
of New Zealand White female rabbits will have 
uterine adenocarcinoma by 4 years of age; 
males are not affected (as they obviously lack 
a uterus). Biomedical research has shown a 
clear distinction between the susceptibility of 
mammary tumors to certain chemicals and 
gender. In the Wistar - Furth rat, 100% of 
females, but only 19% of males, will develop 
mammary tumors to DMBA (a carcinogenic 
chemical used in breast tumor research). 
 Immune s ystem 
 Immunologic dysfunction (including hypersen-
sitivity and allergy, autoimmunity, and immu-
nodefi ciency) may infl uence experimental 
outcome. A litany of agents or situations can 
alter immune function, such as age, nutritional 
status, a host of chemicals, various drugs, select 
food additives, many metals, and specifi c 
microbes. In certain circumstances, the immune 
response may be decreased (most common) or 
increased in response to the interference of 
outside agents. 
 Circadian r hythms 
 Many behavioral, biochemical, and physiologic 
parameters (daily, rhythmic, minima and 
maxima) occur at specifi c times. For example, 
blood counts and coagulation times, plasma 
steroid, body temperature, sensitivity to audio-
genic seizure induction (in gerbils), drug 
metabolism and toxicity (e.g., anesthesia and 
analgesia), and susceptibility to neoplasia are 
infl uenced by circadian rhythms. Although the 
veterinary technician may not be able to impact 
most of these items by modulating circadian 
nutritional status, immune status, circadian 
rhythms, and endocrine factors. 
 Genetics 
 Although genetic factors generally are not a 
concern for small mammal species, excessive 
inbreeding may present a spectrum of disease 
states which interfere with the well - being of the 
pet. For example, malocclusion in a rabbit is 
highly heritable, especially in selected lines, and 
will interfere with normal nutrition and regular 
animal - initiated activities. Malocclusion may 
interfere with grooming, and it will interfere 
with selecting and chewing preferred food-
stuffs. Pet owners should be discouraged from 
breeding their own pets because they generally 
do not have suffi cient numbers of animals to 
provide a varied genetic stock and because 
additional animals may also add to the abun-
dance of unwanted pets. Breeders must have 
genetic diversity if they are to maximize a 
strong and healthy population of pet animals. 
Even in the best of circumstances, mismating, 
spontaneous mutations, chromosomal aberra-
tions, and residual heterozygosity may result in 
undesirable offspring. Affl icted offspring 
should be neutered; if not, at least they should 
be prevented from mating. 
 Age 
 Neonatal animals have an immature immune 
system. That may oversimplify the situation, 
but it is important to note that the very young 
are susceptible to conditions or circumstances 
which would not be important to older animals. 
Rodents less than 1 week of age are exother-
mic , which means they cannot control their 
body temperature. Neonatal pups or kittens, 
when removed from the nest, will become 
hypothermic relatively quickly. As a general 
statement, these young animals begin to 
develop their “ internal furnace ” around 1 
week of age, and by 6 – 8 weeks of age are fully 
capable of maintaining a steady core body tem-
perature. Age becomes critically important 
when considering placement of the cage in a 
room where the windows allow sunlight and 
there is variable air fl ow. A stable, and even 
warm, place is important for the well - being of 
neonatal animals. Although not as pronounced, 
the same kinds of concerns exist for the very 
old animal too. In both cases the status of 
Introduction 5
approach is generally desirable (e.g., rodents ’ 
preference for solid fl oors over wire fl oors), it 
must be managed for its effectiveness (e.g., a 
preference for sunfl ower seeds may interfere 
with generalized nutrition and well - being). 
 Cage d esign 
 The style or design of the cage used for housing 
the animal affects its well - being. All other 
factors being the same, cage design can deter-
mine the amount of air, light, and sound the 
animal receives. Cage design can also impact 
the amount of heat, humidity, and gaseous 
waste dissipated into the macroenvironment. 
Again, all items being equal, plastics or poly-
carbonate caging materials tend to be an 
acceptable compromise for most situations. 
Plastics fi lter the light, diminish the sound, and 
foster a stable microenvironment (heat or 
cool). However, if not properly ventilated, 
plastics may also limit the amount of fresh air 
available and thus increase ammonia level, 
humidity, and the risk of airborne infection. 
 Studies generally indicate that static (plastic -
 walled) caging is preferable to slatted wire -
 walled caging for most small mammals. Many 
pet owners choose slatted wire - walled cages 
because it allows for increased “ communica-
tion and interaction ” with their pet, but such 
caging can have signifi cant disadvantages. For 
example, a slatted wire - walled cage will allow 
free exchange of air, but air fl ow through an 
accumulation of fecal matter is not a good idea. 
The preferred caging design is one that pro-
vides for normal physiologic and behavioral 
needs, allows conspecifi c social interaction, 
facilitates development of hierarchies within or 
between enclosures, remains clean and dry, has 
adequate ventilation, assures access to food 
and water, serves as a secure environment, is 
free of sharp edges, and allows an animal to be 
observed with minimal disturbance. 
 Cage accessories should receive the same 
general consideration as caging materials. 
Items that come in direct contact with the pet 
should be nonreactive, nonpalatable, smooth 
and impervious, durable, corrosion resistant, 
and sturdy. In certain specifi c situations natural 
materials such as wood may be used, although 
the wood should be in the form of branches 
from pesticide - free trees, without signs of tree 
disease or damage, and replaced frequently to 
rhythms, it is worthwhile to recognize that cir-
cadian rhythms may impact therapies, enrich-
ment strategies, and outcomes of the pet 
patient. 
 Endocrine f actors 
 Sex hormones are important determinants of 
hepatic cytochrome P450 enzyme activity. Cas-
trating male rats decreases the ability to 
biotransform xenobiotics and, by extension, 
can affect the required amount of anesthetic for 
subsequent events (i.e., castration may extend 
the effectiveness and duration of anesthesia). 
Neonatal gonadectomy of select strains of mice 
leads to high incidence of estrogen - secreting 
adrenal tumors; so if small mammals are to be 
neutered, awaiting puberty in the species may 
be worthwhile. 
 EXTRINSIC FACTORS AFFECTING 
WELL - BEING 
 Extrinsic factors are those that are external to 
the animal and include physical factors(mac-
roenvironment vs. microenvironment, cage 
design, caging accessories), chemical factors 
(air, water, diet, and drugs), microbial agents, 
stressors, and environmental factors (tempera-
ture, humidity, ventilation, illumination, and 
noise). 
 Physical f actors 
 The single most important thing a veterinary 
technician can do is to stop thinking of small 
mammals as small humans. Just because 
humans would like something does not mean 
it is a good choice for the small pet. The focus 
of consideration for the pet ’ s well - being is the 
animal ’ s environment: The microenvironment 
is the environment immediately surrounding 
the animal. It may be the cage, the pen, the 
box, or the room. The microenvironment is 
where the animal lives. By extension, the mac-
roenvironment is where the animal ’ s container 
is maintained — the macroenvironment is where 
the humans live. Although the macroenviron-
ment contributes extensively to the microenvi-
ronment, one must be principally focused on 
the “ nose of the beast ” to achieve a preferred, 
healthful, supportive, and enriching microenvi-
ronment. One way to state it is “ what is the 
animal ’ s preference? ” Even though this 
6 Exotic Small Mammal Care and Husbandry
true that variations in relative humidity are 
better tolerated at lower temperatures, due to 
heat loss mechanisms of most animals. Low 
relative humidity may be more associated with 
pollution - (e.g., ozone and dust) associated res-
piratory disease while high relative humidity 
may be more closely linked to infectious disease 
(e.g., fungi and bacteria) transmission. 
 Temperature extremes also have an effect on 
other aspects of animal care and support. 
Lactating rats exposed to 95 ° F (35 ° C) for 6 
hours daily produced less milk than rats housed 
at 72 ° F (22 ° C) Reproduction in rats also 
decreases markedly at 90 ° F (32 ° C) (e.g., 
retarded testicular development). 
 Thermo - n eutral z one 
 The thermo - neutral zone (TNZ) is that range 
of temperatures where no energy is expended 
by an animal to either cool or heat itself. The 
TNZ differs by species and does not necessarily 
relate to the comfort of the animal. As a general 
rule, animals are most comfortable at a tem-
perature toward the low end or just outside of 
the low TNZ temperature. Exposure of unad-
apted animals to temperature higher than 85 ° F 
or lower than 40 ° F without access to shelter 
may produce clinical effects that could be life 
threatening. 
 If the temperature change is of short dura-
tion and low magnitude, then few signs are 
expected and even fewer will be observed. 
However, if the temperature deviation contin-
ues (duration and magnitude), animals will 
exhibit huddling, curling up, nest building, and 
increased general activity (all are signs indicat-
ing a desire to remove itself or protect itself 
from the environment). If the deviation contin-
ues further (duration and magnitude), animals 
will alter their metabolism rate and will 
consume more water and more (or less) food; 
the growth rate will also be affected. In 
cases where the temperature changes are colder, 
animals will enter into hibernation, torpor, 
or aestivation, will begin nonshivering ther-
mogenesis (brown fat utilization), will have 
peripheral vascular changes shunting more 
blood to the core of the body and away 
from the appendages (the tail of rodents is 
used for thermoregulation to eliminate excess 
heat), and will exhibit piloerection (hair 
standing up). 
prevent ingestion or allow for it to become 
unsanitary. Wood of certain trees may have 
undesirable products (e.g., tannins in oak, aro-
matic hydrocarbons in pine and cedar) that 
could negatively impact the pet animals, and 
therefore such wood should not be used. Gal-
vanized metal and rubber stoppers may be 
used, but only if the animal shows no interest 
in chewing or licking the metal or rubber. Both 
the zinc in galvanized metal and the rubber of 
the stopper may have a negative impact on the 
animal ’ s well - being. 
 Water 
 Too little water is not good and too much 
water is not good either. Water should be 
checked daily, as lack of water can kill in as 
little as 24 hours! Many small animals will not 
eat if they are not able to drink; considering 
that most animal feeds are dry kibble, an 
absence of water may also result in feed intake 
concerns. In species with a large cecum or 
appendix (e.g., guinea pigs and rabbits), where 
the microbes are dependent upon a fl uid envi-
ronment, lack of suffi cient water may also 
result in gut dysbiosis and could result in 
disease from microbial toxin production or die -
 off of desirable microorganisms. 
 Feeders 
 The style of feeder used for a species is depen-
dent upon the needs of the species, but all feeders 
have common criteria for selection. A feeder 
should allow access to food, minimize contami-
nation with feces and urine, and accommodate 
group housing considerations, which may 
require multiple feeding and watering points, 
while also optimizing the diet consumption. 
 Temperature and h umidity 
 Species - specifi c temperature and humidity pref-
erences are reviewed in the species chapters, 
but certain generalized concepts and issues 
remain. Management of a stable environment 
is the most critical aspect of temperature and 
humidity. Constantly changing temperature 
and humidity is more harmful to the well - being 
of the animal than any specifi c temperature 
(within reason of course). A general recom-
mendation for all species is 30% to 70% rela-
tive humidity. Although there is little evidence 
for strict control of relative humidity, it is also 
Introduction 7
owner whether the animal is kept exclusively 
indoors (where light and dark are generally the 
same year round) or whether the animal is 
principally an outdoor animal (where light and 
dark cycles may vary signifi cantly over the 
year). As a general guideline, small animals 
require only 325 lux (approximately 30 foot -
 candles) of light for normal function and 
development. 
 Noise 
 Noise is a signifi cant factor for the well - being 
of small animals, but it is rarely considered. 
Small animals tend to hear at a higher fre-
quency compared with humans, but most also 
hear well at the human upper end (yes, heavy 
rock music is heard by the pet rat). Noise levels 
around animals should never exceed 85 dB as 
auditory effects of noise can occur at > 85 dB. 
The effects are dependent upon the intensity of 
the noise and the duration (either point or 
cumulative) of the noise event. Destruction of 
sensory hairs and supporting cells can start at 
90 dB, mechanical damage in rats occurs at 
160 dB, and pain has been reported in rats 
at 140 dB. Rats have developed inner ear 
damage after prolonged exposure to 100 dB. 
 Noise also produces direct physiologic 
effects. Increases in serum cholesterol and in 
adrenal weights occur in rats exposed to 83 dB 
and intermittent sound of 114 dB. Audiogenic 
stress due to pulsed noise exceeding 83 dB may 
cause reduced fertility in rodents, and audio-
genic seizures occur in gerbils and select strains 
of mice. 
 Radios, alarms, and timers should not be 
placed close to small animals. Computer video 
screens, large fans, and other household motors 
frequently have ultrasounds that can be highly 
distressful to small animals. These devices 
should not be used near small animals unless 
they have been checked for ultrasonic frequen-
cies. In some cases, artifi cial background noise 
may be useful in masking sudden unexpected 
noise. 
 Transportation 
 Any time the animal leaves its home cage, it is 
being transported — usually just for a trip to the 
backyard but sometimes much further. Trans-
portation can be a signifi cant stressor for these 
species, requiring an acclimation period after 
 If the temperature deviation (duration 
and magnitude) lasts for 14 – 21 days, then 
the body increasesits fat stores, thickens 
the fur coat, and signifi cantly restricts heat 
radiation. 
 Ventilation 
 The purpose of ventilation in most circum-
stances is to remove thermal loads, dilute 
gaseous and particulate contaminants, and 
adjust moisture content. Few, if any, pet cages 
are so secure that oxygen needs of the animal 
are ever in doubt. 
 The macroenvironment of most homes pro-
vides a fresh air exchange of one to two air 
changes per hour. Adequate room ventilation 
does not necessarily ensure adequate ventila-
tion of the microenvironment! 
 Although not generally a concern, if 
ammonia in the cage is high or the bedding 
remains moist for extended periods, then the 
cage ’ s location should be considered and 
perhaps changed or a supplemental fan should 
be provided to assure a suffi ciently dry cage. 
Because small mammals may also cause an 
allergic response, a response that can be cumu-
lative, it is generally preferable to maintain the 
cage as close to an exhaust air duct as possible, 
but not immediately adjacent to the exhaust 
vent to prevent strong drafts that can stress the 
animal. 
 Illumination 
 Small mammals are generally crepuscular 
(more active at dusk or dawn). They do not 
require light as intense as humans and in fact 
will tend to withdraw from intense light levels. 
They will adjust to the light schedules we use 
in our homes, but left alone small mammals 
prefer 14 : 10 (light/dark) to 10 : 14 (light/dark). 
Increasing or decreasing light levels can affect 
breeding receptivity in some species, but less so 
in others. Albino animals have pink eyes and 
are relatively more susceptible to phototoxic 
retinopathy than pigmented species. Albino 
animals, if maintained in continuous light, can 
develop blindness within 18 months. Illumina-
tion can also affect medicinal treatment through 
hepatic enzyme activation. During the light 
cycle, rodents given a barbiturate will sleep 
longer than rodents given the same dose during 
their dark cycle. It is important to ask the pet 
8 Exotic Small Mammal Care and Husbandry
not genetically placed handholds, and the tail 
of a mouse was not placed there so you could 
safely pick it up. Veterinary technicians have a 
special duty to teach and train pet owners on 
proper methods of restraint and handling. 
 Chemicals 
 The potential list of chemicals that could nega-
tively impact animals would be an entire study 
in toxicology, but we shall concentrate on 
general concepts and issues related to chemical 
exposure. Air, feed, water, bedding, and caging 
materials may all present potential chemical 
concerns. Chemicals may enter via damaged 
skin, the intestinal tract, or the respiratory 
tract. While the list of potential effects of chem-
ical insult is long, the more common outcomes 
are changes in the hepatic microsomal enzymes, 
the biotransformation of medications, and the 
regulation of oxygen radical removal (associ-
ated with cancer development). 
 Chemicals may serve as local irritants, 
produce generalized disease, alter immune 
functions, provide allergen exposure, be a 
source of mutagen, or even function as a 
teratogen. 
 Air q uality 
 Air quality is not simply an argument for clean 
air or suffi cient air, but rather for appropriate 
air. Air can become a disadvantage for these 
small mammal species. 
 At 68 ° F (20 ° C), air moving at 60 linear feet 
per minute has a cooling effect of 45 ° F (7 ° C). 
Air this cold, no matter how clean, can signifi -
cantly stress the animals, especially the neonate 
or the geriatric animal. High airfl ow also has a 
 “ wash - out effect ” upon pheromones. 
 Clean air is not necessarily a good concept 
either. Because animals communicate by phe-
romone, in some cases even to the exclusion of 
verbal communication, elimination of pher-
omones prevents the creation of a “ home sweet 
home ” for the pet and never allows its com-
plete integration into the cage environment. 
 Air can also be excessively dirty. Humans 
can sense airborne ammonia at around 25 ppm 
(parts per million). Animals begin to show res-
piratory impact of elevated ammonia at 10 ppm. 
In some cases, low - level ammonia enhances the 
potential disease impact. Mycoplasma pulmo-
nis , in the presence of low - level ammonia, will 
transportation before “ normal ” signs are once 
again observed. Adolescent rats require 1 – 5 
days for complete physiologic recovery after 
being transported. The use of a similar cage, 
with familiar accessories, the same food, and 
some of the same water can lessen the effect of 
the transport. During transport, animals should 
be protected from sunlight or wind by placing 
an opaque cover over the cage. The vision 
system of animals sees things differently from 
humans, and the rapid and repeated movement 
that occurs during transit can be highly stress-
ful. If transport occurs in a vehicle the cage 
should be secured on the fl oor or seat of the 
car using a bungee cord or similar device to 
prevent tumbling in the event of a quick stop. 
Care should be taken to secure the top and 
bottom of the cage to prevent dislodgement 
and escape of the animal during transit. 
 Overcrowding and i solation 
 Animals are generally social creatures (certain 
exceptions occur during breeding season or due 
to reproductive processes). Animals may expe-
rience adverse conditions from being either 
overcrowded or isolated. Overcrowding can be 
mitigated to some degree by effective utiliza-
tion of enrichment paradigms (e.g., hiding 
boxes, red fi lm). In many cases, aggressive 
behavior will be strain - or even sex - specifi c. 
Group - housed mice show marked adrenal 
response that is directly proportional to the 
animal density. In these conditions, the subor-
dinate animal has the higher adrenal weight 
and plasma cortisone level due to its stress 
associated with being subordinate. 
 Once social groups have been established, 
fi ghting may occur if the groups are reassorted 
or if a new member joins the group. Breeding 
and reproduction can also be infl uenced by 
group housing. Grouped - housed rodents fre-
quently become anestrous and will synchronize 
the estrous cycles in the presence of a male 
(Whitten and Bruce effect). 
 Handling 
 Regular and gentle handling reduces animal 
stress and decreases the risk of fear - provoked 
biting. Correct handling and restraint tech-
niques are critical. Failure to handle gently and 
correctly may result in injury to the animals 
and to the handler. The ears of the rabbit are 
Introduction 9
mins or minerals may alter drug metabolizing 
systems, affect membrane integrity, or predis-
pose to the effects of carcinogens. In certain 
cases, selection of specifi c treats may serve to 
benefi t the animal ’ s well - being, as in the case 
of vitamin C requirements and guinea pigs, or 
roughage requirement and rabbits. In all cases, 
diet milling date and storage conditions should 
be monitored because fat - soluble vitamins will 
be leached when stored at high temperatures 
and other vitamins may lose potency if stored 
for excessive periods of time. Just because it 
looks like a pelleted pet ration doesn ’ t mean it 
is worth feeding to the pet. The most important 
concern for a dietary discussion is to avoid 
abrupt diet changes; when changes are required, 
do so over a period of 2 – 3 weeks if possible. 
Although not as habitual as other animals, 
these small mammals can benefi t from chang-
ing the feed from time to time and familiarizing 
them with alternate feedstuffs. Such planning 
has on occasion facilitated the medical man-
agement of a sick patient when presented 
with diets different from those served at 
home. 
 Adventitial d iseases 
 Diseases common to particular species will be 
addressed in each of the species chapters. 
have an increased severity of lung lesions, 
enhanced growth of the organism, and greater 
adherence (decreased clearance) of secondary 
bacteriain the lungs. 
 Water q uality 
 Most pet animals are provided drinking water 
from the home tap. In some cases, it is wonder-
ful water, but in other cases, it may be a 
concern for the pets and their owners. Although 
most municipal water is treated with chlo-
ramines to discourage bacterial growth, high 
levels of chloramines may affect the immune 
system. Stressed or injured animals may benefi t 
from fi ltered water until their return to a 
healthy state. 
 Diets 
 Dietary requirements are addressed in the 
species chapters of this text, but they deserve a 
general mention in our review of external 
factors that may affect the well - being of the 
pet. Likely the most common cause of dietary 
modifi cation is provision of treats. Many pet 
owners will use treats to encourage specifi c 
behavior to get the pet to eat. Treats should be 
limited and never exceed 5% of the total 
required dietary intake of the animal. Varia-
tions in quantity or quality of essential vita-
 Enrichment 2
 The strong and interactive relationship between 
a pet and its human companion serves to 
benefi t both. If we begin with the premise that 
 “ animals are what make us humane ” (another 
way to say it is “ animals are the basis for our 
compassionate relationships to other creatures, 
including humans ” ), then our desire to maxi-
mize their environment and make their lives as 
comfortable as possible becomes a logical 
reason for considering enrichment of the pets ’ 
environment. Recognizing the bond that exists 
between humans and animals, as well as the 
value animals bring to the human existence, 
makes the desire to enhance the environment 
of animals an easy discussion. 
 Enrichment in many contexts simply means 
creating an environment that both allows and 
encourages species - specifi c activities. For 
example, rodents like to burrow and aquatic 
species like to hide behind or within structures. 
If we provide a deep layer of soft sand for the 
aquatic creatures and a box for the rodent pet, 
we haven ’ t caused any harm, but we have 
missed an opportunity to make their environ-
ments as “ normal ” as possible. 
 “ Normal ” is quite diffi cult to truly assess in 
animals, especially those that have never seen 
the out - of - doors. Our perceptions of normal 
must be guided by the animal ’ s interest in and 
motivation to use the enrichment item. Even 
though many captive animals have never lived 
in the “ wild, ” enrichment strategies can be 
guided by the natural habitats and behaviors 
of their wild counterparts. A clear recognition 
of normal is critical to a complete patient 
assessment as well as selection of enrichment 
11
strategies for the patient under consideration. 
If you are unaware of normal, how will you be 
able to assess a change, either positive or nega-
tive, in the animal you are observing? Knowing 
normal is the key to quality enrichment of the 
animal ’ s life! 
 Development of an ethogram is one way to 
determine normal. An ethogram compares the 
time budgeted by the animal for a given task 
or activity. By observing the actions or activi-
ties from a range of options, one can deduce 
that this animal fi nds greater satisfaction with 
activity A over activity B. The more the obser-
vations, the more confi dence one has in the 
outcomes of animal ethograms. A word of 
caution is necessary at this point: each of us 
would rather eat candy than swim four lengths 
of the pool, but we would all agree that the 
pool exercise would be more benefi cial, espe-
cially if performed daily. Consideration of 
animal “ preferences ” using educated judg-
ments can guide the technician in selecting ben-
efi cial activities or devices for the environmental 
enrichment. 
 The goal of an enrichment strategy is to 
improve (or maintain) the health of the animal. 
Animals that are active and engaged in their 
environment are also generally more healthy 
than those that sit quietly for hours and hours 
with little to do and nothing to explore. 
 “ Doing ” is a part of being healthy. Enrichment 
can also be used as a tool for assessing the 
health and well - being of animals. Animals that 
lack exploratory behavior may be in discom-
fort from osteoarthritis or other disease states. 
Providing enrichment through exploratory 
12 Exotic Small Mammal Care and Husbandry
tecting the individual animals. Although not 
the same as direct contact, being able to hear 
each other and see each other may provide suf-
fi cient interaction to decrease stress and 
improve well - being. Mirrors may be used for 
animals that have well - developed sight, but 
shiny surfaces can also be a detriment, espe-
cially if the animal is frightened by refl ections 
or is an individual that is aggressive toward 
other members of its species. Seeing a refl ection 
in a mirror can stimulate social behavior, 
encourage activity, and even provide for a 
sense of companionship. Exercise can be either 
social or nonsocial. Small mammals may be 
transferred from their home cage to an exercise 
pen for various periods of time. The novelty of 
the exercise pen will stimulate the pet and 
encourage exploration. The use of an exercise 
pen also requires that we consider the advan-
tages and disadvantages of such an arrange-
ment, especially if there are multiple species 
using the same area. The exercise pen should 
be sanitized effectively between uses. Most of 
the small mammal species are either prey or 
predator, depending upon the context of the 
moment. A rat is generally considered a preda-
tor to a mouse, but if a ferret were introduced, 
then the rat could be considered the prey 
species. Placing a ferret in an exercise pen, then 
removing it and placing a rat in the same pen 
without sanitation, would not be a pleasant 
experience for the rat: it would sense the preda-
tor animal and would be more concerned with 
escaping and evading the predator than with 
the novelty of curious exploration. 
 Small rodents, especially gerbils, mice, and 
rats, are thigmotactic , meaning they prefer to 
be near a wall than in an open space. Knowing 
this, one should consider maximizing wall sur-
faces as an enrichment strategy and, to the 
extent possible, minimizing the wide - open 
spaces in the home cage or the enrichment pen. 
This can be accomplished by use of tunnels, 
boxes, or other devices that provide wall 
surfaces. 
 Small mammals (e.g., rodents, rabbits) are 
 crepuscular , a term used to describe animals 
that are primarily active during twilight (either 
or both dawn and dusk). There are two behav-
ioral relationships of such animals that can 
facilitate selection of an appropriate environ-
ment and care strategy. 
behavior (e.g., hiding treats in grass, in hay, 
or inside boxes), especially when provided 
just prior to the dark cycle, will decrease 
stereotypic behaviors common of poorly 
enriched animals. Keen observation of an 
animal during enrichment activities will provide 
several useful clinical tools for assessing the 
condition of the patient. Observation of an 
animal ’ s activity level is one method the veteri-
nary technician may use to “ hear ” what the 
animal is saying. 
 Enrichment falls into two general categories: 
social enrichment and nonsocial enrichment. 
Social enrichment requires interaction of the 
animal with other animals or with humans. 
Social enrichment may include time spent 
holding, petting, walking, or playing with the 
pet. Social enrichment is important to decrease 
the pet ’ s anxiety or “ reactiveness ” to humans. 
Generally speaking, an animal that has spent 
signifi cant quantities of time with humans, and 
has been handled gently during those interac-
tions, is less likely to bite or scratch than one 
that has had limited human contact or rough 
handling. However, having human social inter-
action is not the only way to provide enrich-
ment to the animal. 
 Often, conspecifi c interactions (e.g., interac-
tion with one ’ s own kind) are themost advan-
tageous. Conspecifi cs already understand the 
language of the species; they recognize common 
odors, see common visuals, and react in a 
similar manner to other stimuli. In other words, 
conspecifi cs already know how to read moods, 
respond appropriately, and communicate 
readily. For social species, whenever possible, 
animals should be housed with members of 
their own species. In certain cases, there are 
restrictions on how conspecifi c housing should 
occur. For example, hamsters raised alone and 
then grouped as adults will often attack and 
severely injure each other. Rats, however, are 
highly social animals and, given the option, 
will curl together when sleeping and will be in 
close contact when awake. These are examples 
of direct social enrichment. 
 Social enrichment may also be indirect. 
Animals may be placed nearby, but without the 
ability to touch. Since most small animals com-
municate in a hearing range above human 
hearing (ultrasound), proximity of location 
may provide good social enrichment while pro-
Enrichment 13
sores from the wire surface, the use of wire 
fl ooring in most applications is not recom-
mended. A modifi cation of the wire fl ooring 
concept is the slatted fl oor, where the surface 
is composed of fl at bars approximately ¼ inch 
wide or larger. These fl oors are preferred to 
wire and do assist in keeping the animal dry 
and clean, but they do not allow for bedding 
products and, depending upon the caging type, 
may be drafty for the animal. In most applica-
tions, the preferred outcome is a compromise 
between the most easily sanitizable environ-
ment and the most enriched environment. 
 For burrowing animals, providing clean, 
absorbent, and soft material on a solid nonpo-
rous surface (e.g., plastic) to dig and construct 
nests and passageways allows the animal an 
opportunity to explore, to follow its curiosity, 
and to build its “ home. ” At times, the compro-
mise between providing soft and absorbent 
materials and providing materials that can be 
effectively sanitized becomes troublesome. 
Selection of an appropriate substrate for the 
comfort of the animal while assuring effective 
sanitation often requires the use of different 
materials (e.g., a hard easily sanitizable surface 
for the exterior and a soft absorbent material 
for the interior). 
 For most species, cage placement is a critical 
item. For example, the placement of the cage 
near a window could offer some species an 
enriching atmosphere with novel stimuli during 
the course of the day; for others, especially 
guinea pigs, placement near a drafty window 
would provide short - term enrichment but 
increase the infectious disease potential (e.g., 
guinea pigs are highly stressed by drafty condi-
tions). Placement near a window also requires 
close monitoring of the cage temperature. Sun-
light streaming through on a sunny day can 
increase the cage temperature above the optimal 
range in a very short period of time, even to 
dangerous levels. Small mammals are more tol-
erant of cold than of heat, and they can rapidly 
develop hyperthermia when in direct sunlight. 
When we remember the crepuscular nature of 
many of these species, most will sleep during 
the day; thus the placement near a window for 
novel stimuli becomes more of a health concern 
than an enrichment advantage. 
 The cage environment is another variation 
of nonsocial enrichment. Cages may have 
 First, crepuscular animals have decreased 
bright light vision and enhanced dim light 
vision. The best overall enrichment strategy for 
these animals includes protection from direct 
or intense sunlight. Crepuscular animals will be 
most active when the lights are low. Light in 
most homes is at the high end of the preferred 
intensity for small mammals, so decreasing 
light levels by turning off a light or two may 
increase the pet ’ s activity level. Using a night 
light in the pet ’ s room may simulate a moonlit 
night and, for crepuscular species, may keep 
the animal active most of the night. 
 Second, crepuscular animals lack the ability 
to sense red or yellow light. We can take 
advantage of this knowledge by surrounding a 
sleeping box with red or yellow color (e.g., a 
fi lm or a plastic sheet). The animal will believe 
it is dark, but humans can view the animal 
inside. Using a red or yellow fi lm may allow 
good observation of the patient without the 
patient being aware it is being observed. As an 
aside, the defi nition of crepuscular includes the 
terms matutinal (or matinal, indicating activity 
at dawn) and vespertine (indicating activity at 
dusk). Most small mammals prefer one or the 
other, but will have activity during both time 
periods. 
 In addition to exercise, proper caging selec-
tion can be considered a nonsocial enrichment. 
Sanitizable products (e.g., metal, plastics) are 
generally preferable to nonsanitizable products 
(e.g., wood). Certain metals should be avoided 
(e.g., zinc – coated metals, copper, and iron) as 
these products can be ingested or absorbed into 
the animal ’ s system and cause disease. From a 
sanitary standpoint, the use of hard plastic or 
metal provides an easily sanitizable surface. 
However, from the perspective of an animal ’ s 
well - being, such materials can be highly disrup-
tive to the animal ’ s comfort. Metal is cold and 
hard, and plastic can be too. Both products are 
nonabsorbent, preventing the segregation of 
waste products in the environment. Some have 
suggested the use of wire mesh or screening for 
animals. In theory it allows waste products to 
migrate from the animal ’ s environment and 
keep the animals dry. However, studies have 
shown that animals prefer hard surfaces to 
wire surfaces. When considering that a geriat-
ric animal may have diffi cultly moving on wire 
or that a heavy animal may have ulcers or feet 
14 Exotic Small Mammal Care and Husbandry
from the sharp edges commonly found on the 
chips. 
 Paper products, depending upon the source 
and processing of the paper, may be useful to 
consider, but there may also be disadvantages 
with these products. Paper may have residual 
ink or bleaching agents that may affect their 
use. 
 Fibrous products can be very useful for 
small mammal bedding. The long fi ber length 
facilitates nest building, encourages manipula-
tion, and provides enhanced opportunity for 
foraging. Disadvantages may include the source 
of fi brous products. Corn or beet husks may 
have residual fungal contamination if not prop-
erly treated (generally autoclaved) and managed 
(kept cool and dry). These concerns with fungal 
interference intensify when the fi brous prod-
ucts become wet. 
 Bedding type also affects thermoregulatory 
stability, core temperature, and motor activity. 
Mice housed on deep bedding maintain signifi -
cantly higher core temperatures during the day. 
During the night, however, core temperatures 
and motor activity show no difference, prob-
ably more related to activity on the bedding 
rather than burrowing into the bedding. 
Although deeper bedding has a positive impact 
upon core body temperatures, deep bedding 
can also present a risk of touching the water 
bottle sipper and draining the bottle of water, 
wetting the bedding, and causing hypothermia 
in the caged animals. In this case, the deep 
bedding presents the opportunity to injure the 
animal rather than to support its well - being. 
 Animals do have preferences for certain 
types of bedding. Beddings consisting of rela-
tively small particles (1.2 mm × 1.6 mm) are 
generally avoided by rodents, whereas large 
fi brous bedding materials are preferred by mice 
and rats. Size and manipulability are among 
the main determinants of the appreciation of 
bedding particles by mice and rats. 
 Lastly, when considering the air in the cage, 
ammonia is the single most common and most 
important airborne pollutant in the pet cage. 
Certain beddings have a higher ammonia gen-
eration potential thando other bedding materi-
als. The following bedding materials are ranked 
from highest to lowest in ammonia generation 
potential: aspen shavings; pine shavings; 
reclaimed wood pulp; loose virgin pulp; hard-
hiding places and foraging opportunities 
(hiding feed in burrows, burying feed in Astro-
turf, mixing a desirable feed into the fi bers of 
a sheet of synthetic fl eece, or other similar 
devices that encourage the animal to “ work ” 
for the feed reward). The cage environment 
may also include balls, mobile toys, oddly 
shaped items to chew, natural wood products, 
or even small sections of fabric that were used 
by the human companion (a small square of 
old bedding used by the human companion will 
have residual human scents that can facilitate 
a familiarity between the animal and the 
human). Natural products, such as branches or 
leaves, should be removed and replaced when 
they become excessively soiled with 
excrement. 
 Bedding can serve an enormous role in the 
well - being and enriched environment of these 
animals. The amount of bedding used should 
be suffi cient to keep the animal dry between 
cage changes, without coming into contact 
with watering devices. Bedding selection is also 
an important variable affecting the well - being 
of the pet. 
 Bedding made of softwood products such as 
pine or cedar may affect the animal ’ s metabo-
lism and may in some cases actually interfere 
with recovery from anesthesia or even disease 
states. For example, red cedar shavings are 
commonly used for pet bedding because the red 
cedar smells fresh. That fresh smell is princi-
pally two aromatic hydrocarbons (cedrene and 
cedrol) that induce specifi c liver enzymes, 
which can alter rates of anesthesia and interfere 
with metabolism of certain medications. Like-
wise, spruce and pine shavings contain alpha -
 pinene, another volatile hydrocarbon that also 
induces hepatic enzymes. Heat treatments 
(such as autoclaving) can reduce the concentra-
tion of aromatic hydrocarbons and might 
prevent induction of hepatic microsomal 
enzymes. 
 Hardwood shavings (beech and aspen) or 
corncob chips are generally preferred over the 
softwood beddings. Hardwood products do 
not have the volatile compounds found in soft-
wood products. Hardwood is absorbent and 
can serve as effective bedding material. Hard-
wood bedding is available in a variety of chip 
sizes (to be discussed later). Hardwood may 
also cause injury to the neonate or the infi rm 
Enrichment 15
subsequent gastrointestinal distress). Guinea 
pigs enjoy green leafy vegetables such as kale, 
but should not be given iceberg lettuce since it 
has almost no nutritional value and may cause 
GI distress in large volumes. Hamsters and 
gerbils are hoarders and prefer to hide feed for 
eating at a later time; providing at least some 
of the ration on the fl oor of the cage and mixed 
into clean bedding is a more natural situation 
for these species and will foster positive behav-
iors (as opposed to feeding in a food bowl, or 
especially feeding with a wire - bar hanging lid). 
Rodents enjoy oil seeds (e.g., sunfl ower seeds), 
but the quantity should be restricted since 
given the choice rodents will consume only 
sunfl ower seeds and develop nutritional defi cits 
by failing to consume suffi cient balanced 
ration. 
 At other times, the use of supplementation 
can have medicinal value. Although most 
animals internally manufacture the compo-
nents of vitamin C and therefore do not require 
vitamin C in the diet, guinea pigs are one 
species that cannot, and therefore must 
consume suffi cient quantities of vitamin C or 
they will develop scurvy. Providing guinea pigs 
a small enrichment of a citrus fruit (e.g., orange, 
lemon), especially if the ration being fed is not 
wood chips; recycled paper; pelleted virgin cel-
lulose; and corncobs. We must note, however, 
that routine and regular cage cleaning can 
overcome concerns with ammonia generation 
in any of the bedding products. 
 How then should a bedding product be 
assessed for supporting the well - being of the 
pet? An ideal bedding material should be dust 
free, nonpalatable, absorbent, and free of 
microbial and toxic contaminants. No bedding 
is ideal for all species. No bedding is ideal for 
all care conditions. However, bedding is a con-
trollable environmental factor — one that may 
enrich or detract from the environment! A 
good place to start is with hardwood bedding. 
 Feed products may also be used as a means 
of enrichment, though overfeeding of supple-
ments can have deleterious effects. All pets 
require a nutritious ration. Small pets consume 
small quantities of feed, and provision of too 
much enrichment feed can interfere with the 
required basic nutrition of the pet. As a general 
rule, supplements and food enrichments should 
not exceed 10% of the standard diet. Feed 
supplements must also be selected based upon 
the species. Rabbits enjoy carrot tops, but 
should not be given too many carrots (exces-
sive amounts of carrots can cause gastritis and 
 Table 2.1 Rodents (mice, rats, hamsters, gerbils, degus): These normal behaviors should be considered in 
the development of an overall strategy of enrichment. 
 Gnawing The teeth of many rodents grow continually and, without gnawing, will overgrow and cause 
pain or disease. Gnawing is a critical life behavior for rodents. 
 Burrowing, hiding, 
daylight sleeping 
 Rodent eyes are sensitive to intense light, such as occurs during the day. Burrowing is one 
method of escaping from intense sunlight. 
 Exploring, 
climbing, seeking 
feed 
 Rodents are “ explorers ” ; they prefer to search for their food as a means of “ normal ” food 
acquisition. Hiding feed encourages exploration, increases exercise, and provides normal 
behavior. 
 Grooming Grooming of one ’ s cage mates is a strong social activity that builds bonds of trust and 
relationship. Grooming also serves as basic sanitation for the coat, removing excess debris 
and dander while combing and smoothing the fur. 
 Nesting Nesting is a behavior that consolidates the “ family, ” provides social contact, facilitates 
grooming, and gives a sense of a thigmotactic environment. 
 Thigmotactic Rodents do not have good vision; therefore they depend upon their whiskers and sensory 
fi bers around the head and shoulders. Rodents prefer being next to a wall and will choose a 
close and confi ned space rather than an expanse of fl oor. 
 Neophobia Although novel stimuli are useful, presentation of new - tasting food enrichments will generally 
be met by a small nibble, then restraint from further consumption until time has passed. This 
evolutionary survival mechanism prevents the ingestion of poisonous foodstuffs. Novel 
foodstuffs may initially be rejected but subsequently preferred to another novel introduction. 
 Table 2.4 Ferret: These normal behaviors should be considered in the development of an overall strategy 
of enrichment. 
 Alligator roll This is a behavior important for establishing dominance between two animals. 
Single animals may grab the socks, feet, or loose skin of their human companions 
in an attempt to “ alligator roll ” them. 
 Backing into a corner This is a behavior seen for urinating and defecating, but it may also be a sign of 
fear. If the animal hisses, the fear response is likely. Picking up these animals can 
result in serious injury. 
 Bottle brush, “ puffy ” tail A “ puffy ” tail, or “ bottle brush tail, ” is an indication of fright or excitement. Other 
signs should also be noted (hissing would be fear) to determine the actual meaning 
of this sign. 
 Chasing or lunging This is a playful behavior. 
 “ Dancing ” Jumping from side to side in a playful series of antics, “ dancing ” is generally a sign 
of excitement, but it may also be an indication of aggression. 
 Dooking or chirping This is the sound made while excited.Food, water, litter - pan 
digging 
 This is a normal behavior where the animal digs for its feed or for a place to 
defecate. This can occur at any time and, while not harmful, can be a mess to 
clean up. 
 Food or water bowl tipping This is a behavior probably related to the curious and digging nature of the animal. 
 Hissing Hissing is a behavioral sign of fear or anger or a show of intimidation. 
 Running into things This is not necessarily a behavior of its own; ferrets have poor eyesight and, when 
in a hurry, can run directly into things — or off a balcony or stairs. 
 Table 2.2 Guinea pig: These normal behaviors should be should be considered in the development of an 
overall strategy of enrichment. 
 Scatter, freeze When sensing “ danger, ” the guinea pig will do one of two things: either run 
quickly to a less dense location or freeze in place and hope the danger passes. 
 Linear hierarchies Guinea pigs form strong relationships to other guinea pigs in the area. Separating 
or regrouping animals may engender unnecessary distress. 
 Territorial Guinea pigs are strongly territorial. They do not readily accept newcomers and 
will chase or corner new inhabitants. 
 Vocalizations Guinea pigs have a large repertoire of sounds and infl ections to communicate 
their intentions. This is one species where vision is less important than indirect 
communication such as vocalization. 
 Cover Being a burrow - dwelling rodent, guinea pigs prefer some form of cover to be 
 “ safe. ” Enrichment strategies should always include opportunities to hide. 
 Table 2.3 Rabbit: These normal behaviors should be considered in the development of an overall strategy 
of enrichment. 
 Chewing Rabbits require regular chewing to maintain proper apposition of the front teeth. 
 Thumping Rabbits do not vocalize very well or very frequently, but rather use thumping as a 
means to communicate their message. Often associated with an aggressive posture, 
thumping can be the harbinger of an aggressive action to follow. 
 Locomote (hop or roll) Rabbits use these maneuvers to escape or evade. Rabbits in a playful mood may also 
exhibit these behaviors. 
 Nudging, nose Rabbits use nudging as a softer means of communicating (softer than thumping). The 
rabbit will press its nose in the direction it desires the opponent to move. 
 Fur pulling Does will pull their fur immediately prior to kindling to provide soft down for their kits. 
 Grooming Rabbits groom constantly, never satisfi ed with the present status of things. Rabbits that 
are prevented from grooming may appear depressed. 
16
Enrichment 17
 Table 2.5 Sugar glider: These normal behaviors 
should be considered in the development of an 
overall strategy of enrichment. 
 Nocturnal Sugar gliders have acute night vision, 
but limited day (bright - light) vision. 
 Vocalization They often vocalize for no apparent 
reason, but likely for simple 
communication. 
 Social In nature they may be found in groups 
of 30 – 50. 
 Territorial Sugar gliders use urine and scent glands 
to identify territory (even humans). 
fresh, will prevent the development of this 
disease while also providing a pleasing enhance-
ment to the regular diet. 
 Enrichment strategies should always be 
developed in the context of the natural behav-
ior of the animal. For example, rodents gener-
ally have limited vision but a well - developed 
sense of smell and hearing. Providing visual 
stimulation to the pet rat or gerbil will likely 
not provide an enriching activity. However, 
providing items that stimulate the sense of 
smell or the sense of hearing may be far more 
engaging and satisfying to the animals. 
 All animals have certain behaviors, some-
times based upon physiological needs (e.g., 
gnawing in rodents to keep the teeth trimmed). 
Examples of behaviors include those given in 
Tables 2.1 – 2.7 . 
 Table 2.7 Chinchilla: These normal behaviors 
should be considered in the development of an 
overall strategy of enrichment. 
 Social Chinchillas are highly social and 
active animals that like 
companionship. In their natural 
habitat, they live in herds ranging 
up to 100 or more animals. 
 Nocturnal They are most active at night and 
sleep during the day. Eating occurs 
at night. 
 Fur dropping Frightened animals will “ drop fur ” 
rapidly. 
 Chirps or 
squeaks; barks 
 These are common communication 
sounds indicating any number of 
expressions from play to fear. 
 Table 2.6 Hedgehog: These normal behaviors should be included in an overall strategy of enrichment. 
 Curling This is a behavior to indicate “ enough, ” or simply a need to escape for a time. 
 Anointing, or anting Production of a large amount of foamy saliva when they encounter an unfamiliar 
smell — they will lick at the novel item until frothy saliva develops, then rub the 
saliva on their quills. This is the process of anointing, also called anting. 
 Chirping, whistling, purring These are sounds indicating comfort and contentment — a happy hedgehog. 
 Snorting, hissing, clicking These are sounds indicting discomfort, fear, or aggression — an unhappy hedgehog. 
 Foraging for food Digging and climbing are benefi cial hedgehog behaviors. 
 Solitary These are not social animals and should be housed separately. 
 Diurnal They are most active at dawn and dusk, although some remain on the move until 3 
a.m. Frequent handling during the day can help change the hedgehog ’ s habits and 
help reduce the nighttime activities. 
 ENRICHMENT STRATEGIES 
 Enrichment strategies must be considered spe-
cies by species. The types and styles of enrich-
ment for one species can be inappropriate for 
another species. Enrichment strategies should 
be formulated according to the normal behav-
iors of the pet; therefore it is key to clearly 
recognize normal behavior in a species prior to 
recommending any enrichment strategy. 
 Rodents 
 Almost any item that is nontoxic and safe can 
be used as part of a rodent enrichment strategy. 
These may include the following: 
 • Bedding (burrowing and exploring for 
rodents) 
18 Exotic Small Mammal Care and Husbandry
 • Burrows (generally a plastic product) 
 • Cage dividers (increasing wall surfaces) 
 • Climbing accessories 
 • Exercise devices (running wheels) 
 • Film canisters 
 • Foraging devices 
 • Tunnel (provides closeness and wall surface) 
 • Gnaw blocks or sticks 
 • Group or social housing (not hamsters, adult 
male mice, or female rats) 
 • Hide boxes 
 • Ladders 
 • Mazes 
 • Soft music 
 • Nest boxes or nest - building material (hay, 
tissues, or wood - wool) 
 • Platforms 
 • PVC pipe ( ½ - to 1 - inch diameter is best) 
 • Ramps 
 • Shelves 
 • Shuttle box (also called transport box) 
 • Tubes (such as those from rolls of toilet 
tissue or paper towels) 
 Rabbits 
 Almost any item that is nontoxic and safe can 
be used as part of a rabbit enrichment strategy. 
These include the following: 
 • Balls (hard plastic) 
 • Bedding (straw, wood chips) 
 • Burrows (oatmeal cans, boxes) 
 • Free range (e.g., a clean and pesticide - free 
backyard) 
 • Fresh fruits or vegetables (limit sugary fruits; 
use more vegetables) 
 • Gnawing objects (aspen wood or apple 
wood) 
 • Group housing 
 • Soft music 
 • Nest boxes 
 • Nesting material (tissues, straw, dust - free 
hay) 
 • Pair housing (except adult males) 
 • PVC pipe 
 • Resting shelf 
 • Roughage or forage (limit alfalfa; prefer 
grass hay) 
 • Varied diet 
 • Suspended shiny objects 
 • Brass “ canning rings ”(tough enough to 
chew, soft enough to bend) 
 Ferrets 
 Almost any item that is nontoxic and safe can 
be used as part of a ferret enrichment strategy. 
These include the following: 
 • Balls 
 • Bite cups 
 • Crickets 
 • Foraging devices 
 • Fur - covered movable toys 
 • Hammocks 
 • Hide - and - seek tunnels 
 • Mazes 
 • Moving preymodels 
 • Music 
 • Nest boxes 
 • Plastic burrows 
 • PVC tubes 
 • Shelters 
 • Swimming pans 
 Sugar g lider 
 Almost any item that is nontoxic and safe can 
be used as part of a sugar glider enrichment 
strategy. These include the following: 
 • Bedding 
 • Burrows 
 • Cage dividers 
 • Climbing accessories 
 • Climbing frame 
 • Foraging devices 
 • Group or social housing 
 • Hide boxes 
 • Mazes 
 • Soft music 
 • Nest boxes or nest - building material (hay, 
tissues, or wood - wool) 
 • Platforms in cages 
 • PVC pipe (2 - to 3 - inch diameter is best) 
 • Ramps 
 • Shelves 
 • Shuttle box (also called transport box) 
 • Tubes (such as those from rolls of toilet 
tissue or paper towels) 
 Hedgehog 
 Almost any item that is nontoxic and safe can 
be used as part of a hedgehog enrichment strat-
egy. These include the following: 
Enrichment 19
 • Bedding 
 • Burrows 
 • Cage dividers 
 • Dust baths 
 • Foraging devices 
 • Group or social housing 
 • Hide boxes 
 • Ladders 
 • Mazes 
 • Soft music 
 • Nest boxes or nest - building material (hay, 
tissues, or wood - wool) 
 • Platforms 
 • PVC pipe (2 - to 3 - inch diameter is best) 
 • Ramps 
 • Sand bath 
 • Shelves 
 • Shuttle box (also called transport box) 
 • Tubes (such as those from rolls of toilet 
tissue or paper towels) 
 
 
 • Bedding 
 • Burrows 
 • Cage dividers 
 • Foraging devices 
 • Group or social housing 
 • Hide boxes 
 • Ladders 
 • Mazes 
 • Soft music 
 • Nest boxes or nest - building material (hay, 
tissues, or wood - wool) 
 • Platforms 
 • PVC pipe (2 - to 3 - inch diameter is best) 
 • Ramps 
 • Shelves 
 • Shuttle box (also called transport box) 
 • Tubes (such as those from rolls of toilet 
tissue or paper towels) 
 Chinchilla 
 Almost any item that is nontoxic and safe can 
be used as part of a chinchilla enrichment strat-
egy. These include the following: 
 Preventive Medicine 3
 Veterinary technicians are often required to 
consult and advise clients concerning the 
health of their pets and the potential diseases 
that may be transmitted to the client ’ s family. 
Even more frequently, veterinary technicians 
work alongside the veterinarian in diagnosing 
and treating communicable diseases. A clear 
understanding of the potential diseases that our 
pets, or our patients, may share is crucial for 
the veterinary technician to achieve maximum 
impact. Let ’ s begin, therefore, with the recogni-
tion that we have a closely intertwined rela-
tionship with our pets and our animal charges. 
We live with animals and we work with 
animals. Diseases that we may pick up at work 
can affect our pets at home, and diseases at 
home can affect the health of our patients at 
work. Animals can carry a number of diseases 
that are important to our pets — and our family 
members. 
 The term for diseases transmitted between 
animals and humans is “ zoonoses. ” The World 
Health Organization defi nes zoonoses (zoono-
sis, sing .) as “ Those diseases and infections 
which are naturally transmitted between verte-
brate animals and man. ” The effects of zoo-
notic disease may be direct illness, negative 
feelings of family members about the pet, mon-
etary cost of treating the disease, potential legal 
implications if the animal infects or injures a 
neighbor child, and the loss of the friendship 
and companionship of the animal due to 
unmitigated disease. Recognizing zoonotic 
disease and the potential for zoonoses is an 
important aspect of quality medical service. 
However, before discussing specifi c zoonoses, 
21
we must understand a few basic concepts about 
zoonotic disease. 
 There are fi ve primary modes of zoonotic 
disease transmission: fecal material, urine, 
blood, saliva, and milk. Certain of these modes 
of transmission are easy to envision. For 
example, fecal contamination has and will 
make people ill; parasites and other disease -
 causing agents are often transmitted in fecal 
material. Other methods of transmission may 
not be as obvious; for example, saliva is not 
something we think we are sharing with our 
patients, but as they groom themselves they are 
spreading their saliva on their fur coat. We 
then pet them or brush them, and in addition 
to removing loose fur we are also removing 
dried saliva proteins or potentially infectious 
particles. Recognizing the mode of disease 
transmission is important to understanding 
how to limit the spread of disease. 
 Each of these primary modes of transmis-
sion may be further subdivided according to 
the specifi c route by which a contagion gains 
admittance to the body: aerosolization (breath-
ing in airborne contaminants), mucous mem-
brane (touching our mouth, eyes, or nose with 
contaminants on our hands), or contact with 
the bedding or animals (this route may include 
direct contact with the skin). Considering these 
routes of infection, and adding the modes of 
transmission, we can see that washing our 
hands to protect ourselves from fecal or urinary 
output may not be suffi cient. Fecal material 
may dry out, releasing small particulate matter 
that becomes airborne and is subsequently 
inhaled. 
22 Exotic Small Mammal Care and Husbandry
 H. Route of transmission: Viral infections 
more readily result from mucous membrane 
contact than “ palm of the hand ” contact. 
 Zoonoses may also be classifi ed in a number 
of ways. A useful system of classifi cation is 
based on the type of life cycle of the infective 
organism. This system is most practical and 
seems the most useful in planning a preventive 
medicine program. The following categories 
are recommended by the World Health Orga-
nization Expert Committee on Zoonoses: 
 A. Direct zoonoses: Agent is transmitted from 
infected vertebrate host to a susceptible ver-
tebrate host by direct contact, fomite, or a 
mechanical vector. No developmental 
change or propagation of the organism 
occurs during the transmission. Examples 
are rabies, trichinosis, and brucellosis. 
 B. Cyclozoonoses: Agent requires more than 
one vertebrate host, but no invertebrate 
host. Examples are human taeniasis, echi-
nococcosis, and pentastome infections. 
 C. Metazoonoses: Agent multiplies, develops, 
or both in an invertebrate host before trans-
mission to a vertebrate host is possible. 
(This means that a defi nite prepatent or 
incubation period must be completed before 
transmission.) Examples are arboviruses, 
plague, and schistosomiasis. 
 D. Saprozoonoses: Transmission of these 
infections requires a nonanimal develop-
ment site or reservoir, such as food plants, 
soil, or other organic material. Examples 
are larva migrans and some of the mycotic 
diseases. 
 The direction of disease transmission is also 
worthwhile knowing. For example, if a disease 
is common in animals and easily transmitted 
among animals but only rarely infects humans, 
then the control and prevention measures are 
very different from a disease that is shared 
readily and equally between humans and 
animals. The manners of describing the direc-
tion oftransmission are as follows: 
 Anthropozoonoses: Infections transmitted to 
humans from lower vertebrates. 
 Zooanthropozoonoses: Infections transmitted 
from humans to animals. 
 Knowing the mode and route of infection is 
not suffi cient alone to clearly understand the 
probability of disease transmission from 
animals to humans. The probability of devel-
oping a disease is infl uenced by several factors, 
including the following: 
 A. Length of time the animal is infec-
tive: Animals with parasitic diseases often 
are infective for years. Animals with viral 
diseases often are infective for days to 
weeks. 
 B. Length of the incubation period in 
animals: For diseases with long incubation 
periods, infected animals may be observed 
as “ normal ” for long periods of time, 
because the animals may move housing 
locations or even die before becoming infec-
tive for humans. 
 C. Stability of the agent in the environ-
ment: Enveloped viruses (e.g., canine coro-
navirus, murine hepatitis virus) are less 
hardy and can be more easily destroyed by 
common disinfectants than nonenveloped 
viruses (e.g., feline leukemia, parvovirus, 
rabies), which are very hardy and may 
persist for long periods of time. This factor 
is most important in direct transmission, 
where the virus may be exposed to environ-
mental changes. 
 D. Population density of the animals in 
the home or clinic: Large concentra-
tions of animals spread disease more 
rapidly than few animals in a common 
location. 
 E. Husbandry practices: Daily sanitation, 
especially when tied to an appropriate dis-
infecting chemical, can disrupt or break the 
infectious cycle and prevent transmission of 
disease. 
 F. Control of wild rodents and insects: Gener-
ally, wild animals have a variety of infec-
tious agents, some of which may be 
signifi cant to the pet or the client. 
 G. Virulence of the agent: Another way to 
think of virulence is how “ hot ” is the agent, 
or how “ aggressive ” is it, or how “ rapidly 
will it spread? ” For example, Coxiella bur-
netti requires only 10 organisms to cause 
disease, whereas Pasteurella generally 
requires thousands of organisms to cause 
disease. 
Preventive Medicine 23
sionally it has been transmitted to humans. 
Veterinarians and veterinary technicians 
exposed to the blood of infected animals are 
the primary risk populations; pet owners are 
generally considered not at risk of this disease, 
except in the cases where there are immune -
 compromised people (e.g., cancer patients, 
HIV - infected individuals, transplantation 
patients). These groups should not handle 
infected dogs. 
 Transmission: There are two recognized 
modes of transmission of B. canis : 
 1. Most likely cause for technicians — contact 
with infected animals, especially aborted 
fetuses, fl uids or membranes, or urine 
 2. More likely cause for pet 
owners — airborne 
 Disease in a nimals: In animals, the disease 
may cause the following: 
 1. Abortions 
 2. Infertility, testicular abnormalities, poor 
semen quality in dogs 
 3. Inapparent infection, which may also be 
common, as indicated by seropositivity 
(presence of antigen or antibody) 
 Disease in h umans: In the few human cases 
recorded, bacteremia was a fairly common 
fi nding, along with lymphadenopathy, spleno-
megaly, fever, headache, chills, orchitis, weak-
ness, nausea, and weight loss. However, many 
of these same symptoms could be caused by the 
annual fl u outbreak or any number of other 
minor diseases. 
 Diagnosis: A rapid slide agglutination test is 
available. Standard tube agglutination has been 
used, and a 2 - mercaptoethanol test can distin-
guish an active disease from a recovery from 
earlier illness. In certain cases, blood cultures 
and additional serologic tests may be used to 
confi rm slide test results. 
 Treatment: The therapy varies by geography. 
Generally, tetracycline/streptomycin combina-
tion has been used in the United States, whereas 
doxycycline/rifampin combination has been 
the preferred option in Europe. 
 Amphixenoses: Infections maintained in both 
humans and lower vertebrates; may be natu-
rally transmitted in either direction. 
 Zoonoses may also be organized by etiologic 
(causative) agent. This is the structure we will 
follow for our continuing review: 
 A. Bacterial 
 1. Bacteria 
 2. Spirochetes 
 3. Chlamydia 
 4. Rickettsia 
 5. Mycoplasmas 
 B. Fungal 
 C. Viral 
 D. Parasitic 
 1. Protozoan 
 2. Helminth 
 a. Nematode 
 b. Cestode 
 BACTERIAL DISEASES 
 Systemic i nfections 
 Brucellosis 
 Agent: Brucellosis is caused by the following 
organisms: 
 Brucella abortus — cattle, sheep 
 Brucella canis — dogs 
 Brucella melitensis — sheep, goats 
 Brucella suis — swine 
 Reservoir and i ncidence: Of the preceding 
species, we will only casually recognize the sig-
nifi cance of the agricultural impact of B. 
abortus . Instead we will focus our attention on 
 B. canis , once considered the most likely zoo-
notic agent, due to extensive numbers of 
roaming animals. Even today, the prevalence 
of Brucella may be as high as 10% in dogs in 
the US and the UK, and substantially higher in 
other parts of the world (e.g., Mediterranean 
and Arabian Gulf regions, Latin America, 
Africa, and Asia). Brucella canis is well 
adapted to dogs and is not the subject of any 
large - scale eradication program in the general 
dog population, as Brucella has been in agri-
cultural animals. Humans appear to be quite 
resistant to B. canis infection, although occa-
24 Exotic Small Mammal Care and Husbandry
reservoir is swine (pharynx may be heavily 
colonized), so veterinary care of swine —
 whether farm - reared or pet pigs — should 
include consideration of this agent. There have 
also been cases of this disease associated with 
caring for sick puppies and kittens but without 
a clear connection to swine. 
 Y ersiniosis — Y . p estis 
 Agent: Yersinia pestis is a gram - negative rod -
 shaped bacteria and is the causative agent of 
plague. 
 Reservoir and i ncidence: This disease is 
endemic in certain wild rodent populations in 
southwestern United States as well as in Africa 
and Asia. Plague surveys have also found evi-
dence of this agent widespread in wild animal 
populations all across the western Great Plains 
region of the United States. Whereas prairie 
dogs and select peromyscus (deer mouse) and 
related species are reservoirs in the United 
States, the more important reservoirs world-
wide are the roof rat, Rattus rattus , and the 
urban rat (sometimes also called the Norwe-
gian rat), R. norvegicus . In the United States, 
from 1970 to 1995, a total of 341 cases of 
human plague (average, 13 cases per year) were 
reported (CDC, 1996 ). The disease is also asso-
ciated with cats, goats, camels, rabbits, dogs, 
coyotes, prairie dogs, and fox squirrels. Cats 
have been the source of infection in several 
human cases. Domestic cats are a principal 
cause of human pneumonic plague in the 
United States. Persons working in veterinary 
practices should be especially aware of the risks 
involved in handling Y. pestis – infected cats. 
Dogs and cats may serve as passive transport-
ers of infected rodent fl eas into the home. 
 Transmission: The primary method of trans-
mission involves contact with infected rodent 
fl eas (over three - quarters of human cases) or 
direct rodent contact. Fleas may remain infected 
for months, so the disease may be apparent, go 
into “ hiding, ” and recur at a later time. A 
protein secreted by Yersinia serves as a coagu-
lase that causes blood ingested by the fl ea to 
clot in the proventriculus. The bacillus prolifer-
ates in the proventriculus,

Outros materiais