The effects of diet on anatomy, physiology and health in the guinea pig

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Volume 1 • Issue 1 • 1000103J Anim Health Behav Sci, an open access journal
OMICS International
Review Article
Journal of
Animal Health and Behavioural Science
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Witkowska et al., J Anim Health Behav Sci 2017, 1:1
Keywords: Guinea-pig; Anatomy; Physiology; Diet; Nutrition;
Health; Genetics
Background to the Guinea Pig
e domestic guinea pig, Cavia porcellus, also known colloquially
as the ‘cavy’ belongs to the Caviidae family of rodents, originating
from the grasslands and Andes Mountains of South America [1].
Following its domestication in 500-1000 AD, the guinea pig has been
kept as an important source of food and is still eaten in many parts
of South America today [2,3]. Since being introduced to Europe by
Spanish colonialists in the 16th century, they have been commonly
kept as pets, as well as used extensively in medical research with the
rst documented experiments performed on guinea pigs dating back
to 1780 [1,4]. Since that time guinea pigs have played a pivotal role in
epidemiological study and pharmaceutical development [1]. eir use
in research has been declining rapidly since its peak in the 1960s, from
around 2.5 million annually in the USA, to just over 200,000 in 2010
[5,6]. As the population of guinea pigs used in research declined, the
popularity of the guinea pig as a pet has soared. In 2012 around 13,000
guinea pigs were being used in UK laboratories, yet approximately 1
million were being kept as pets in UK households, an equal number to
that of rabbits [7,8]. Indeed the Pet Food Manufacturer’s Association
have reported the guinea pig as the UK’s 7th most popular pet, kept in
more households than any other pet rodent [8].
Anatomy and Physiology of the Guinea Pig
Although there is wide variability across the literature, it is
generally believed that sow pups reach sexual maturity earlier than
boars, with puberty reached at around six weeks in sows and nine to
ten weeks in boars [9]. Upon reaching sexual maturity, females come
into oestrus approximately every 16 days [10]. If breeding is desired, it
is important to do so before the sow reaches six to seven months of age,
to prevent the permanent fusion of the pubic symphysis and resultant
dystocia [11]. Adult weight is reached at eight to 12 months of age, with
boars weighing up to 1200 g and sows up to 900 g [2]. Despite reaching
adult weight at this age, CT scanning has evidenced that bone growth
and development are still occurring beyond 12 months [12]. Life
expectancy varies broadly across the literature from two to eight years
but is generally considered to be between around ve or six years [13].
As a hystricomorph, or ‘porcupine-like’ rodent alongside chinchillas
and degus, the guinea pig sow has a characteristically long gestation
period of between 59 and 72 days, approximately double that of the
rabbit, and gives birth to precocial young [2]. Litter size varies from two
to six, with an average of three or four pups, each weighing between
60 and 120 g [1]. e young pups are born mobile, fully-furred, with
their eyes open and teeth present, and are, therefore, able to consume
solid food within a few hours, although will still suckle for two to three
weeks [2,10].
e literature is divided as to how the circadian rhythm of guinea
pigs can be classied [14]. Some authors have categorised guinea pigs
as diurnal, being most active during daylight hours, whilst others have
found them to show no circadian rhythm at all, instead having two
to three hour periods of activity followed by a short period of rest
[2,10,11,15]. Whilst this discord is seen across literature covering both
domesticated pet guinea pigs and those used in research laboratories,
it is generally agreed that wild guinea pigs tend to be crepuscular, with
most activity seen at dawn and dusk [1,10]. It has also been found that
the majority of behaviour of domesticated guinea pigs is similar to that
of their wild counterparts [10]. In the wild, guinea pigs are sociable,
rarely aggressive, vocal animals, living in groups of ve to ten animals
[16]. ey have a good sense of sight and smell, although primarily
use sound/language to communicate, being capable of producing up
to 11 dierent vocalisations for specic situations [11,17]. However,
their excellent hearing does mean that they are particularly sensitive
to, and easily distressed by, loud or sudden noises, and tend to freeze
in response [11]. In distinct contrast to other rodents, guinea pigs do
not dig burrows or build nests [18]. Wild guinea pigs favour tunnels
or nests made by other animals as well as the protection provided
naturally by vegetation [19].
*Corresponding author: Rutland CS, School of Veterinary Medicine and Science,
The University of Nottingham, Sutton Bonington Campus, Loughborough, UK, Tel:
0115 9516573; E-mail: Catrin.rutland@nottingham.ac.uk
Received November 21, 2016; Accepted December 22, 2016; Published
December 28, 2016
Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The
Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig. J Anim
Health Behav Sci 1: 103.
Copyright: © 2017 Witkowska A, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Abstract
Given the increasing popularity of the guinea pig as a pet it is, perhaps, surprising that relatively little is published
as to their husbandry and dietary requirements. Indeed, a review of the literature currently available to owners,
scientists and clinicians alike has found it to be scarce, highly variable and, at times, overtly contradictory. This review
and data collection collates the husbandry and dietary information available and discusses the variable information
available and the differing practices published in the literature in relation to the guinea pig. A questionnaire was
also used to gather owner-reported data on feeding regimens from both the UK and Poland in order to better
understand the range of feeding habits that owners employ. Despite the lack of information available in comparison
with that available for other companion and livestock animals advances in knowledge are being made. With guinea
pig numbers increasing in many countries and owners seeking husbandry and veterinary advice and interventions it
is imperative that we understand guinea pig health and welfare issues. The data and review gives novel insights into
how guinea pig husbandry affects health and welfare.
The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig
Witkowska A, Price J, Hughes C, Smith D, White K, Alibhai A and Rutland CS*
School of Veterinary Medicine and Science, The University of Nottingham, Loughborough LE12 5RD, UK

Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig.
J Anim Health Behav Sci 1: 103.
Page 2 of 6
Volume 1 • Issue 1 • 1000103J Anim Health Behav Sci, an open access journal
that articial UVB given to guinea pigs could be a good way to raise
and maintain vitamin D levels but that longer term studies would be
advisable. Guinea pigs do not respond well to change and enjoy a set
daily routine [10]. In particular, they can become distressed following
movement of housing or changes in food and water containers, and as
such, must be slowly habituated to any changes [10,26].
Dietary Requirements of the Guinea Pig
e guinea pig is an obligate herbivorous hindgut fermenter
and practises caecotrophy, consuming its own pellets [1,2,27]. is
is to ensure maximal nutrient absorption from the caecal digesta,
particularly vitamins K and B12 produced by the bacterial ora of the
gut [24]. e guinea pig gastrointestinal tract is dominated by a large
caecum which breaks down the cellulose content of the diet [28].
Dental care and diet
e hypsodont dentition of the guinea pig is designed to deal with
large amounts of brous plant material with the open-rooted teeth
erupting continuously throughout life [10,29]. It has been suggested
that, if there is insucient bre in the diet, the teeth are not adequately
worn down and severe malocclusions can occur, resulting in an inability
to eat and starvation [2]. erefore timothy or grass hay should make
up the majority of the diet and be fed ad libitum [2]. Müller investigated
the eect of dierent pelleted diets on incisor wear and tooth length in
female juvenile guinea pigs (mean starting body mass 488 g ± 22 g, aged
9–11 weeks) [30]. Four dierent complete pelleted diets of increasing
abrasiveness were tested, based on Lucerne, grass, grass with the
addition of rice hulls and grass with the addition of rice hulls and sand
respectively and a control of grass hay as a h diet. e study found
a positive relationship between tooth growth and wear of upper and
lower incisors in guinea pigs, indicating than in ever-growing teeth,
the growth rate is regulated to compensate for wear, in common with
a similar study on rabbits [31]. Contradictory to previous suggestions
that internal abrasives cannot wear down tooth enamel or can only
cause limited damage, the study indicates that internal abrasives do
actually wear down teeth [32,33]. It was found that adding whole hay
to the diet had a signicant eect on tooth length of the upper incisors
and cheek teeth but not the lower incisors or lower cheek teeth, and
only dietary eects on wear and growth could be shown in the lower
incisors [30,31]. Upper cheek tooth wear was highest using grass
with the addition of rice hull and sand, and upper cheek teeth were
aected more by abrasives than lower cheek teeth, with both of these
characteristics similar to results in rabbits. is suggests that there is a
similar mechanism of incisal gnawing and chewing in both species and
suggest that feeding whole forages, while important when increased
wear of incisors is aimed at, will not dier in the wear eect on cheek
teeth when compared to high-bre pellets. Tooth angle of cheek teeth
diered signicantly across diets, regardless of the diet abrasiveness,
also adding to the suggestion that diet abrasiveness plays only a minor
role in dental abnormalities observed in this species [30,31]. erefore
mineral imbalances or genetic predisposition may be a more likely
cause of malocclusion and it should also be noted that these were not
long term diet trials and only juveniles were investigated. e longest
genetics study indicating that breeding may play a role on malocclusion
was carried out in an inbred colony of strain-2 guinea pigs over four
years. Aer each generation of breeding, future breeding stock were
selected from animals which had siblings with no malocclusion
problems noted and preferably no other close relatives aected [34].
e incidence of malocclusion was signicantly reduced (P<0.001) by
breeding from animals with no aected siblings, indicating that the
Husbandry of the Guinea Pig
Due to the highly sociable nature of guinea pigs, most literature
aimed at pet owners advises keeping guinea pigs in groups of at least
two [2]. It has been established that keeping an animal with at least
one other compatible individual signicantly reduces stress in many
species of mammals [20]. Despite the recognition that isolation can
compromise an animal’s welfare, scientic needs can justify laboratory
guinea pigs being kept solitarily, in order that interaction between
animals does not interfere with the research being carried out [10]. In
such cases it is the needs of the research that lead housing and husbandry
decisions, rather than simply the welfare of the animal [11]. As a result,
laboratory-targeted literature should be referenced with caution by
domestic owners and by the breeders and practitioners advising them.
Traditionally guinea pigs and rabbits have been housed together, and
up to even the late 1980s owners were advised that cohabiting guinea
pigs and rabbits did not pose a problem [21]. However, it is now
recognised both in the literature targeted at professionals and in advice
aimed at lay owners that rabbits do not make suitable companions for
guinea pigs. A number of concerns have been raised about housing the
two species together, such as their dierent dietary requirements, the
risk of stress to the guinea pig due to bullying, and the risk of injury due
to the powerful kick of rabbits and potential attempts at mating [22,23].
Unsurprisingly it has been demonstrated that guinea pigs actively seek
out fellow guinea pig company in preference to that of rabbits [24].
Additionally rabbits can carry subclinical Bordetella bronchisepta
which can cause pneumonia in guinea pigs [11].
A solid-bottomed enclosure with dust-free bedding such as wood
shavings or shredded paper is the preferred housing, as wire mesh
cages can result in limb lacerations and fractures [11]. Pododermatitis
(also known as bumble foot) can also result from the use of wire mesh
cages, with the development of pressure sores as the bodyweight of the
guinea pig is concentrated on to its relatively small feet [1]. Guinea
pigs do not tolerate high temperatures or humidity well, and therefore
an ambient temperature of around 21˚C, with draughts minimised
should be maintained [11]. Environmental enrichment is important,
in particular the provision of hiding spots such as large bore pipes that
function as tunnels [9].
More recently the question of UVB light requirement in the
guinea pig has been studied in order to ascertain whether there are
any clinical or physiological complications linked to this practice or,
indeed, whether it can improve their health. ere were previously
no recommendations for guinea pig owners in relation to the type of
lighting that should be provided and whether too much, or too little,
UVB caused lasting clinical complications, especially in animals kept
inside. It was postulated that guinea pigs should be used to higher levels
of UVB as in their native environment they are used to high altitudes,
in addition UVB in most other vertebrates is utilized to create vitamin
D but it was not known whether this was essential for guinea pigs
[25]. In this study guinea pigs received either UVB supplement or no
additional UVB and it was observed that 25 hydroxyvitamin D levels
did dier, with higher values being seen in the treatment group (120
mmol/L to just under 80 mmol/L) in comparison to control animals
(20 mmol/L to 40 mmol/L). Ionised calcium was signicantly increased
(1.52 mmol/L in controls and 1.58 mmol/L in supplemented animals,
p<0.0001). e treatment group also had slightly thicker corneas than
controls, but a number of other factors such as prevalence of ocular
disorders, skin abnormalities and dental abnormalities, bone density,
plasma parathyroid hormone, sodium, albumin and total blood protein
levels were not altered between the groups [25]. e authors indicated

Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig.
J Anim Health Behav Sci 1: 103.
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Volume 1 • Issue 1 • 1000103J Anim Health Behav Sci, an open access journal
malocclusion has a genetic basis at least in that strain.
Vitamin C
Another key dietary need of guinea pigs is that of vitamin C or
ascorbic acid as, like humans, they lack the enzyme L-gulonolactone
oxidase that is necessary to synthesise ascorbic acid from
L-gulonolactone [28]. Hypovitaminosis C, also known as scurvy,
usually presents following two to three weeks of insuciency as
lameness or pain due to intra-articular haemorrhage, anorexia, weight
loss and general unthriiness, progressing to death if le untreated
[1,28,35]. Occasionally diarrhoea is also seen [11]. Sub-clinical scurvy
presents as a generalised decrease in immune function, with increased
incidence of bacterial pneumonia, acute enteritis and skin infections
[28].
Guinea pigs need to consume 10 mg/kg of vitamin C daily, which
can be achieved through a balanced diet (with many commercial
guinea pig complete pellet diets containing plentiful vitamin C) or by
adding to the drinking water [28]. Vitamin C degrades faster at higher
temperatures, especially once 30°C is reached and a concentration
dependent degradation is observed when added to water by between
20-50% depending on the dosage given [36,37]. erefore although
vitamin C can be relatively stable, it is suggested that water is changed
every day in order to ensure an appropriate concentration for guinea
pigs, but if well controlled, this could be extended. Shelf lives of pellets
and vitamin C supplements must be adhered to Terril et al. [1]. Other
good dietary sources of vitamin C include roots such as carrots and
beetroot, and leafy greens such as kale, cabbage and dandelions, which
also help to provide guinea pigs with environmental enrichment [2,28].
Since rabbits and other rodents can make their own vitamin C, it is
not added to their pelleted feed and, therefore, rabbit and other rodent
diets are unsuitable for guinea pigs [1]. Moreover, exclusively feeding
a pelleted rat diet to a guinea pig can result in death due to vitamin C
deciency within 14 days [24]. It should be noted that breeding females
require additional nutritional supplementation during pregnancy due
to their two to three fold increase in vitamin C requirement and their
inability to practise coprophagy as the abdomen expands [1,28]. Guinea
pigs also require higher amounts of folic acid and lower amounts
of vitamin D than rabbits and rodents and thus feeding guinea pigs
rabbit or rodent food is likely to result in folic acid deciency and
hypervitaminosis D [9].
Macronutrients
Much work has been carried out by researchers and commercial
feed companies in order to ascertain the appropriate levels of
macronutrients within guinea pig diets. In addition to vitamin C there
are a number of very important factors involved when designing an
appropriate diet. Highlighted throughout the years has been the need
for appropriate levels of n-6 fatty acids, especially in young males [38].
Using linoleic acid as the source of n-6 fatty acids, they concluded that
although 0.24% of total caloric intake was sucient for growth, 0.88-
1.04 percent was optimum in reducing dermatitis levels. e protein
content is also important and within that arginine has been shown to
improve growth [39]. Tryptophan has also been shown to promote
growth and prevent cataracts; the ideal requirement was 1.6-2.0 g/kg
diet [40]. Other minimum amounts of amino acids to enable maximal
growth and nitrogen retention, especially in young guinea pigs include
crystalline L-amino acid 14.2 MJ ME/kg; lysine 8.4 g/kg; 5.4 g/kg each
of phenylalanine and tyrosine; threonine, 5 g/kg; histidine, 3 g/kg;
isoleucine, 5 g/kg; leucine, 9 g/kg; arginine 12 g/kg and valine 7 g/kg
[41-49]. In relation to minerals 8 g calcium/kg and 4 g phosphorus/kg
diet are suggested with low levels particularly aecting bones of younger
animals [50,51]. Magnesium and potassium levels are dependent on
the levels of both calcium and potassium but generally 1-4 g/kg of each
is sucient [52,53]. Many commercially available feeds are available
specically for guinea pigs based on the bulk of research carried out
over the years, it should be noted that much research is also carried out
by the commercial companies in addition to the peer reviewed works
available. Guinea pig requirements oen dier from those observed in
other species such as rats and rabbits. It is essential that care should be
taken when purchasing/developing a suitable guinea pig diet, especially
in the young, pregnant and/or lactating animal.
Fruit and vegetables
e advice regarding whether or not fruit should be fed to
guinea pigs is somewhat conicting. In literature aimed at veterinary
professionals, some authors state that no fruit whatsoever should be
provided, as its sugar content is too high, whereas others maintain that
the feeding of fruits such as kiwi and orange is appropriate [2,9,11].
Dierences in advice directed at owners are also apparent, with some
organisations advocating the feeding of small amounts of virtually all
fruits, some advising unlimited feeding specically of citrus fruits,
whilst others declare that no citrus fruits should be given at all, with
small quantities of apple being the only suitable fruit [54-56].
In order to understand the variability in feeding habits, owners
in the UK and Poland completed an online questionnaire (under
institutional ethical approval, n=197 respondents caring for 500 guinea
pigs). Among the 84 Polish respondents, the English Short-haired and
Abyssinian breeds were the most commonly kept, making up 43%
and 30% respectively of the surveyed animals. In the British survey,
the English Short-haired was again the most popular breed, making
up 41.8% of the guinea pigs kept, with the Abyssinian being the second
most popular breed, but making up just 15.6% of the cohort.
In the UK cohort there was a smaller proportion of owners that
fed commercial guinea pig dry food, just 73.5% compared to 83% of
Polish owners, with 3% of British owners feeding rabbit food and a
further 3% feeding rodent muesli, neither of which meet the guinea
pig’s unique dietary requirements. e UK owners were also less likely
to feed vegetables daily 77% in compared to 98% of Polish respondents
(P<0.0001 chi-square). e frequencies which respondents fed their
guinea pigs fruit and vegetables are shown in Table 1. Interestingly, the
two guinea pigs that were being fed vegetables the least frequently the
UK cohort (weekly and several times per month) were both showing
signs of diculty walking and bunny hopping, which are symptoms
consistent with hypovitaminosis C.
Responses were even more variable on the subject of feeding fruit,
which is perhaps not surprising given the disparity in advice available
to owners in the literature and online. 99% of Polish owners did feed
fruit, but on the whole, much less oen than vegetables. Notably of the
ve animals within this cohort reported to have cataracts, four of them
were fed fruit on a weekly basis, and may therefore have a diet higher
in sugar and at greater risk of diabetes. 83.2% of UK owners surveyed
feed their guinea pigs fruit which is fewer than the Polish owners, and
with much greater variation in frequency (P<0.0001) (Table 1). Of the
264 UK guinea pigs that were fed fruit, eight had been diagnosed with
cataracts (3.03%), whereas only one guinea pig out of the 133 not fed
fruit (0.75%) had cataracts. Of those fed fruit, the highest proportion
of cataracts (15%) was seen in the group that were given fruit several
times per week. Greater sample sizes and further investigation into
the glycaemic levels seen in guinea pigs with cataracts alongside their

Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig.
J Anim Health Behav Sci 1: 103.
Page 4 of 6
Volume 1 • Issue 1 • 1000103J Anim Health Behav Sci, an open access journal
dietary history is now needed to determine how much of a risk factor
fruit is for cataract development.
When looking at potential breed predispositions amongst the
British cohort, the majority of cataracts were seen in the English Short-
haired breed, with 3.4% of this breed being aected. Bone problems
were also seen in the same percentage of English Short-haired animals.
Bunny hopping was much more widely reported among the British
cohort, recorded in 9.3% of English Short-haired, 11.4% of Abyssinian,
40% of Sheltie and 100% of the Satin breed guinea pigs. Intriguingly it
is the Satin breed that has been most closely associated with the bone
disorder osteodystrophia brosa, of which bunny-hopping could be
a manifestation. It would be interesting to follow these cases up and
undertake further investigations to see if they do indeed have this
condition [57,58].
ese data demonstrate the variation in feeding practices across
guinea pig owners. is may be explained by the wide variety of advice
available to owners, both in books, online and in the scientic literature.
Additionally, nding information specically on guinea pigs can be
challenging as it is oen amalgamated into that concerning other small
mammals such as rabbits and hamsters. For example the management
of y strike in rabbits is oen discussed in detail in the literature, but
very little is available with regard to guinea pigs specically [29].
Of greatest concern are the owners that are not feeding a guinea
pig-specic dry food or not feeding vegetables regularly, as this advice
seems to be quite consistent in the literature. Indeed some of the
guinea pigs which were not receiving regular vegetables in their diet
were described as displaying signs consistent with hypovitaminosis C. It is
possible that the UK owners are probably following the latest advice in not
feeding fruit as oen as the Polish owners are, although since sugar content
between fruits can be variable, without knowing the type of fruit being fed
it is dicult to know how much sugar the animal is receiving.
Another study investigated the role of dietary sucrose and fat/
cholesterol on the development of dyslipidemia and non-alcoholic
fatty liver disease (NAFLD). Seventy 10 week old female guinea pigs
were block randomised (on body weight) into 5 groups (n=14). Aer
one week of acclimatisation they were each fed one of ve diets. e
control group were fed chow only and the other groups fed a chow
based diet with either very high-sugar, high-fat, high-fat/high-sugar or
high-fat/very high-sugar respectively [59]. Hepatic steatosis was found
in most guinea pigs fed the high-fat diet but not in the control or very
high-sugar diet group. is suggests that showed that feeding diets high
in cholesterol and fat are the main contributing factors to dyslipidemia
and NAFLD to non-alcoholic steatohepatitis (NASH) in guinea pigs.
Water and changes to diet
eir aversion to change can make guinea pigs very fastidious eaters,
with the slightest alteration in diet resulting in a complete refusal to eat
or drink [11]. erefore any changes in diet, water supply or feeding
receptacles should be introduced very gradually, for example, mixing a
new bag of pellets with the old bag, rather than abruptly nishing one
and then starting another [2].
One study investigated the water delivery system (open dish vs.
nipple/bottle feeders) under diering dietary regimes. On all four diets,
mean water intake was higher when a nipple drinker/water bottle was
available. It was also important to note that water amount varied across
diets (mean water consumption on hay diet from bowls=115.1 g/kg0.75,
nipple drinkers 120.6 g/kg0.75. Parsley diet from bowls=30.1 g/kg0.75,
nipple drinkers=50.6 g/kg0.75. Pellet diet bowls=101.8 g/kg0.7, nipple
drinkers at 138.0 g/kg0.75. Seed mix diet bowls=63.6 g/kg0.75, nipple
drinkers=130.5 g/kg0.75). erefore diet and water delivery method
aected water uptake, high dry matter diets and nipple drinkers
increased mean water uptake [60].
Understanding water consumption is important clinically because a
common problem in guinea pigs is uroliths or kidney stones, commonly
composed of calcium carbonate [61]. e calcium component comes
from excessive calcium in the diet which is ltered out in the kidneys.
If insucient water is consumed this leads to more concentrated urine
sitting in the bladder and, therefore this, contributes to the formation
of stones. Conversely more diluted urine dilutes the calcium carbonate
making larger stones less likely to form, as has been suggested in rabbits
[62]. is demonstrates the importance of the need for guinea pigs to drink
a sucient amount therefore it is clearly a husbandry issue if the water isn’t
provided in the manner that guinea pigs nd best suits them.
Conclusions
Given the wide array of advice available to guinea pig owners, it is
important that practitioners ensure they are up to date with the most
current information when advising owners how to feed their animals.
Of utmost importance is a balanced guinea pig-specic dry food,
with ad libitum forage and daily provision of fresh vegetables rich in
vitamin C. Seemingly fruit should be fed in moderation, perhaps just
as an occasional treat, however if a sucient diverse selection of fresh
vegetables is available, then it may be best avoided entirely. It is also of
note that much of the research into guinea pig diet is many decades old
and whilst much work has been carried out in the commercial arena,
little of the research has been published. is therefore highlights the
potential for more research into guinea pig diet, husbandry and disease.
In order to minimise the propagation of genetic defects, the same
common sense approach used in other species of not breeding from
animals who have a congenital condition, or who have produced
ospring with a congenital defect in the past should be employed.
Further work is needed to fully understand the impact of diet on the
development of conditions such as bone and ocular disorders in the
guinea pig, and perhaps most importantly of all, to ensure that those
ndings are eectively communicated to owners so that they may act
on them.
Frequency of Feed/Country Daily Weekly Fortnightly Several times a
month Monthly Never NR
Poland n=84 Vegetables 82 (98%) 2 (2%) 0 0 0 0 0
Fruit 52 (63%) 25 (30%) 3 (4%) 0 (0%) 2 (2%) 2 (1%) 1
UK n=113 Vegetables 69 (77%) 20 (22%) 0 1 (1%) 0 0 23
Fruit 12 (11%) 40 (37%) 23 (21%) 5 (5%) 10 (9%) 18 (17%) 5
Table 1: Frequency with which Polish and UK owners feed their guinea pigs vegetables and fruit (n=84 and 113 respectively). Number and percentage (adjusted for non-
respondents). NR denotes not responded to that question. Chi square showed signicant differences in the numbers of people that fed their guinea pigs daily vs. weekly or
less both vegetables P<0.0001 and fruit P<0.0001.

Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig.
J Anim Health Behav Sci 1: 103.
Page 5 of 6
Volume 1 • Issue 1 • 1000103J Anim Health Behav Sci, an open access journal
Acknowledgements
The authors would like to thank the owners of the guinea pigs for donating
their time to complete questionnaires and Rutland P for manuscript appraisal.
Ethical permission to undertake the questionnaire was given by The University
of Nottingham. Funding (BB/J014508/1) was provided to CSR by The School
of Veterinary Medicine, University of Nottingham. BBSRC summer studentship
funding was also awarded to CSR to give CH, JP and AW research training.
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Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig.
J Anim Health Behav Sci 1: 103.
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Citation: Witkowska A, Price J, Hughes C, Smith D, White K, et al. (2017) The
Effects of Diet on Anatomy, Physiology and Health in the Guinea Pig. J Anim
Health Behav Sci 1: 103.