CVJ / VOL 48 / JANUARY 2007
The risk of salmonellae shedding by dogs fed Salmonella-contaminated
commercial raw food diets
Rita Finley, Carl Ribble, Jeff Aramini, Meredith Vandermeer, Maria Popa, Marcus Litman,
Abstract — Twenty-eight research dogs were enrolled to determine the prevalence of salmonellae shedding after
consumption of 1 Salmonella-contaminated commercial raw food diet meal. Sixteen dogs were exposed to
Salmonella-contaminated commercial raw food diets and 12 to Salmonella-free commercial raw food diets. Seven
of the exposed dogs shed salmonellae 1–7 days after consumption of Salmonella-contaminated raw food diets.
None of the dogs fed Salmonella-free diets shed salmonellae. No clinical signs were observed in either group. Five
of the 7 dogs shed the same serotypes as those recovered from food samples used for feeding. Results showed the
same serotypes and antimicrobial resistance pattern in 2 of the 7 shedders. Dogs fed Salmonella-contaminated raw
food diets can shed salmonellae and may, therefore, be a source of environmental contamination potentially leading
to human or animal illness.
Résumé — Risque d’excrétion de salmonelles chez des chiens soumis à un régime alimentaire commercial
composé d’aliments crus contaminés aux salmonelles. Vingt-huit chiens de recherche ont été utilisés pour
déterminer la prévalence de l’excrétion de salmonelles après la consommation d’une ration de nourriture commerciale
crue contaminée aux salmonelles. Seize chiens ont reçu une ration contaminée aux salmonelles et 12 une ration
exempte de salmonelles. Sept des chiens ayant consommé la ration contaminée ont excrété des salmonelles de
1 à 7 jours plus tard alors qu’aucun des chiens ayant reçu la ration non contaminée n’en a excrétées. Aucun signe
clinique n’a été observé tant dans un groupe que dans l’autre. Cinq des 7 chiens ont excrété les mêmes sérotypes
que ceux retrouvés dans les aliments contaminés. Les résultats ont montré les mêmes sérotypes et les mêmes profils
de résistance antimicrobienne chez 2 des 7 excréteurs. Les chiens nourris d’aliments crus contaminés aux salmonelles
peuvent excréter des salmonelles et peuvent ainsi constituer une source de contamination environnementale
conduisant potentiellement à des maladies humaines ou animales.
(Traduit par Docteur André Blouin)
Can Vet J 2007;48:69–75
Salmonella infection for dog owners and their communities
(1–3). The prevalence of salmonellae in dogs in the community
is not well established, as dogs can be asymptomatic carriers,
capable of shedding the organism without exhibiting signs
of illness. The prevalence of Salmonella isolation from clini-
eterinarians and public health officials have recognized
shedding salmonellae by dogs as a possible source of
cally healthy and hospitalized dogs has been estimated to be
between 1% and 35% (4,5). Clinical salmonellosis is rare in
dogs, but clinical signs include fever (40°C–41.1°C), anorexia,
diarrhea, bloody diarrhea, abdominal pain, and abortion (5,6).
Asymptomatic dogs can shed salmonellae for 6 wk or more, con-
tinuously during the 1st week, and then intermittently (5,6).
There are various potential sources of salmonellae for dogs,
including unprocessed or raw dog food or pet treats of animal
Foodborne, Waterborne and Zoonotic Infections Division (Finley, Aramini) and Laboratory for Foodborne Zoonoses (Reid-Smith),
Public Health Agency of Canada, 160 Research Lane Unit 206, Guelph, Ontario N1G 5B2.
Department of Population Medicine, Ontario Veterinary College (Finley, Ribble, Aramini, Vandermeer, Popa, Reid-Smith), and
Animal Care Services (Litman), University of Guelph, Guelph, Ontario N1G 2W1.
Address all correspondence to Dr. Carl Ribble; e-mail: firstname.lastname@example.org
Dr. Ribble’s current address is Faculty of Veterinary Medicine, University of Calgary, G380, 3330 Hospital Drive, NW, Calgary,
Alberta T2N 4N1.
Reprints will not be available from the authors.
Funding for this research was obtained from the Ontario Veterinary Pet Trust, Public Health Agency of Canada.
CVJ / VOL 48 / JANUARY 2007
origin. Raw meat obtained from rendering plants and used
to feed dogs can be contaminated with salmonellae and has
been associated with canine salmonellosis (7–9). Raw meat is
the main ingredient in “raw food diets,” a relatively new and
increasingly popular type of dietary trend in dogs. In addition
to raw meat, these diets contain vegetables, grains, and fruit;
they may also include ground bones and are served raw to
dogs as their main meal (10). Raw food diets can be purchased
frozen at pet stores and some veterinary clinics, or they can be
homemade by following recipes found on the Internet (11,12)
or in books (13–17).
Regardless of the possible benefits of raw food diets claimed
by advocates, dogs that consume them are at some risk of
Salmonella infection. Raw meat used for the production of these
diets can originate from several sources, including human-food
grade processing plants, rendering plants, and products no
longer deemed suitable for human consumption (18). As these
diets do not undergo any type of heat processing or steriliza-
tion, existing bacteria and parasites can be present at the time
Joffe and Schlesinger (19) enrolled 20 client-owned dogs at a
veterinary clinic to investigate the risk of Salmonella infections
in dogs consuming raw chicken diets. Ten dogs with previous
exposure to raw food were fed homemade raw food diets and
10 dogs were fed commercial dry dog food. Eight (80%) of the
10 homemade diets tested positive for salmonellae. Three of
the 10 dogs (30%) fed these diets had salmonellae organisms
isolated from samples of their feces. None of the dogs fed com-
mercial diets shed Salmonella in their feces.
The purpose of this study was to further investigate the health
risks that commercial raw food diets pose to the dogs consum-
ing these products and to their owners. The study was linked
to a retail survey (20) of raw food diets that was conducted
in 3 Canadian cities to assess the prevalence of salmonellae in
frozen, commercially available, raw food diets. The objectives
of the study were to determine if dogs shed salmonellae after
consuming a Salmonella-contaminated commercial raw food
diet, and if so, to determine how long it would take them to
stop shedding after a single exposure. A further objective was to
determine whether or not the serotype and resistance phenotype
found in the contaminated raw food diet matched the serotype
and resistance phenotype of the salmonellae isolated from the
Materials and methods
Salmonella-contaminated raw food diets
Commercially available raw food diets were sampled in
Mississauga and Guelph, Ontario, and in Calgary, Alberta, as
part of a study assessing the prevalence of Salmonella in these
products (20). Frozen samples were forwarded to the Canadian
Research Institute for Food Safety (CRIFS) laboratory at the
University of Guelph for testing. One half of each raw food
diet sample was tested for salmonellae and the other half of the
sample was kept frozen. Selection of the samples used in this
study was based on culture results.
Three methods were used in parallel format for the isolation of
salmonellae from commercially available raw food diets (20). The
1st method followed the FDA Bacteriological Analytical Manual
(21). The 2nd and 3rd methods were derived specifically for the
study in consultation with Salmonella experts at the Ontario
Veterinary College, University of Guelph and the Laboratory for
Foodborne Zoonoses, Public Health Agency of Canada (LFZ-
Guelph), Guelph. All Salmonella isolates cultured from the raw
food diet samples were submitted to the LFZ-Guelph for sero-
typing and for antimicrobial susceptibility testing. Antimicrobial
susceptibility testing was conducted by using broth microdi-
lution (Sensititre®; Trek Diagnostics, Westlake, Ohio, USA)
and a panel of 16 antimicrobials (amikacin, amoxicillin/
clavulanic acid, ampicillin, cefoxitin, ceftriaxone, ceftiofur, ceph-
alothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin,
nalidixic acid, streptomycin, sulfamethoxazole, tetracycline,
and trimethoprim/sulphamethoxazole). The resistance break-
points were those used by the Canadian Integrated Program
for Antimicrobial Resistance Surveillance, which are derived
from Clinical Laboratory Standards Institute (CLSI, formerly
Sample size for the feeding trial
A sample size was calculated by using a statistical package
(MiniTab Release B; Mini Tab, State College, Pennsylvania,
USA), based on the highest available prevalence estimate for
salmonellae in dogs, 35%. In order to detect a difference in
Salmonella status between dogs fed contaminated raw food diets
and those fed noncontaminated raw food, the total sample size
required, with Type I and Type II error rates set at 5% and 20%,
respectively, was 46 dogs, 23 exposed and 23 unexposed.
Purpose bred beagle dogs were acquired from a reputable com-
mercial source. Five dogs, 1 more than needed, were randomly
selected prior to each individual trial period. Only dogs that had
stool samples that tested negative for salmonellae for 3 consecu-
tive days were eligible for enrollment. Four dogs, if all 5 were
negative, were randomly selected for inclusion. Information on
age, sex, spay/neuter status, and prior antimicrobial usage was
collected for each dog.
An Animal Utilization Protocol was reviewed and approved
by the Animal Care Committee, University of Guelph. This
committee follows the guidelines established by the Canadian
Council on Animal Care.
The 4 dogs for each trial run were housed in an isolation unit
in individual kennels. Groups consisted of either 3 exposed and
1 unexposed, or 2 exposed and 2 unexposed dogs.
On the 1st 2 d, dogs were fed their normal commercial dog
food to allow an acclimation period to the isolation unit. On the
3rd d, the exposed group was fed Salmonella-positive raw food
diets, while the unexposed group was fed Salmonella-free raw
food diets. All dogs were fed Salmonella-free raw food diets on the
4th and 5th d. From the 6th d until the end of their observation
period, all 4 dogs were fed their normal commercial dog food. All
commercial dog food products fed during the feeding trial were
tested for Salmonella contamination throughout the study.
CVJ / VOL 48 / JANUARY 2007
Dogs remained in their kennels at the isolation unit until
8 consecutive Salmonella-negative fecal samples had been
obtained, at which point they were released from the study and
returned to the Central Animal Facility. Each dog was social-
ized individually for 20 min in the morning and 10 min in the
afternoon while in the isolation unit. Unexposed dogs were
socialized prior to exposed dogs to minimize environmental con-
tamination. A plastic guard was placed on the bottom kennels to
prevent nose-to-nose contact between dogs in kennels and the
dog in socialization. During socialization, dogs were taken out
of their kennels to play, fecal samples were collected, kennels
were cleaned, and the health status of each dog was observed
and recorded on a health-monitoring form. Information on
dog attitude, amount of food intake, presence of vomit, and
appearance of feces was noted. After each individual animal
had been socialized, floors were cleaned with a diluted mixture
of a quaternary detergent/disinfectant (Ascend®; Huntington
Professional Products; St. Paul, Minnesota, USA) and left to
dry for 10 min. Animal handlers wore full protective clothing.
Protective gowns and gloves were changed and boots disinfected
Salmonella isolation from fecal samples
From each fecal sample, 10 g of fresh feces was transferred into
a sterile stomacher bag filled with 90 mL of buffered peptone
water (BPW). Contents were emulsified and incubated at 37°C
for 18 to 24 h. A portion (0.1mL) of the BPW was transferred
into 10 mL of Rappaport Vassiliadis (RV) broth and incubated
at 42°C for 24 h. Following incubation, a loopful of RV broth
was plated onto 3 selective media: xylose lysine tergitol 4 (XLT4)
agar, brilliant green sulfa (BGS) agar, and bismuth sulfite (BS)
agar. The selective media plates were then incubated at 37°C
for 18 to 24 h. After incubation, the plates were examined for
colonies suggestive of salmonellae. If there were any colonies
present, at least 2 typical colonies, as well as 2 atypical colonies,
from each selected plate were plated onto MacConkey agar and
incubated at 37°C for 18 to 24 h.
From each MacConkey plate, presumptive salmonellae were
plated onto nutrient agar plates (NAP) and incubated at 37°C
for 18 to 24 h. From these, biochemical testing was conducted
by using triple sugar iron (TSI) agar and urea slants. Isolates
were incubated at 37°C for 18 to 24 h. If TSI slants were posi-
tive for salmonellae and urea slants were negative, indole testing
followed. If the indole test was negative, then agglutination was
performed by using Salmonella O Antiserum Poly A-I and Vi.
If results from the agglutination test were positive, a loopful of
growth was inoculated onto tripticase-soy agar (TSA) slants.
All Salmonella isolates were forwarded to the LFZ-Guelph for
serotyping and antimicrobial susceptibility testing, as described
above for the raw food samples.
Comparison of the risk of Salmonella isolation from the feces of
dogs in the exposed and unexposed groups was conducted by using
a 2-tailed Fisher’s exact test (22) run on 2 statistical programs
(DISTRIB; William Sears, Department of Population Medicine,
Ontario Veterinary College, University of Guelph, and SAS V8.2;
SAS Institute, Cary, North Carolina, USA). A correction factor of
0.5 was added to all cells in the 2 3 2 table in order to estimate
the relative risk when any of the cells were zero (23).
None of the 50 dogs that were screened tested positive for
salmonellae prior to enrolment in the feeding trial. Because of
welfare concerns associated with having dogs housed in isolation
for extended periods of time, and because the objective of the
study was to detect a significant difference in Salmonella shed-
ding status, not to produce a stable estimate of that difference,
Salmonella prevalence results were assessed periodically, with a
decision to stop the trial early based on achievement of a signifi-
cant difference of P , 0.05. The feeding trial was terminated
early with 28 dogs enrolled in the study from February 18, 2004,
to July 8, 2004. This included 16 exposed and 12 nonexposed
dogs in 7 groups of 4.
The control group averaged 21 mo of age (range: 9–31 mo)
and consisted of 8 males and 4 females. The exposed group
averaged 20 mo (range: 9–33 mo) and consisted of 9 males
and 7 females.
Of the 16 dogs exposed to Salmonella-contaminated com-
mercial raw food diets, 7 (44% with 95% CI: 21%–69%) shed
salmonellae in their feces. None (0/12) of the control dogs
shed salmonellae. The exposed group’s shedding rate (44%)
was significantly different (RR $ 11.4; P = 0.01) from the
zero shedding rate found in the unexposed group. The dogs
in the exposed group started to shed salmonellae 1 to 7 d
after consuming Salmonella-positive raw food diets. Total days
shedding ranged from 1 to 11 d, with a mean of 3.9 d. Five
of 7 dogs had more than 1 d of shedding and days between
shedding ranged from 1 to 9 d (Table 1). None of the 7 dogs
that shed salmonellae had any prior antimicrobial treatment.
None of the exposed dogs developed diarrhea or showed any
Table 1 shows the serotypes and antimicrobial susceptibility
patterns of salmonellae recovered from exposed dogs compared
with the Salmonella isolates obtained from the raw food diets
they consumed. Five of 7 dogs shed the same serotypes as found
in their food. Of these 5, 2 shed only the serotype found in
its food, 1 had 2 serotypes in its food but only 1 in its feces,
1 had 1 serotype in its food but shed 3 serotypes, and 1 had
2 serotypes in its food but shed 3 serotypes. Two dogs shed a dif-
ferent serotype from that identified in its food. One of the dogs
was fed a raw food diet containing S. Thompson, and then shed
S. Typhimurium, while another dog was fed S. Typhimurium,
and then shed S. Thompson.
In most cases, where serotypes matched between food and
feces, the antimicrobial susceptibility pattern also matched. In
dog Devon, the food isolate (S. Heidelberg) was resistant to
ampicillin alone, but the fecal isolate was resistant to ampicillin
and cephalothin. Dog O’Henry was exposed to food containing
S. Heidelberg with 3 patterns and shed S. Heidelberg with the
same patterns plus 2 other patterns, and dog Dundas exposed to
CVJ / VOL 48 / JANUARY 2007
Table 1. Comparison of Salmonella isolates recovered from fecal samples and raw food diets in the canine feeding trial
Days on which feces
were Salmonella positive
(Exposure day = Day 0)
resistance in food
in fecal samples
in food fed to dogs
AMP, CEP, STR
AMC, AMP, CEP, FOX, TIO
AMC, AMP, CEP, FOX, TIO
AMP, CEP, STR, TCY
GEN, SMX, STR, TCY
AMP, CEP, STR, TCY
AMP, CEP, STR, TCY
1 S. Heidelberg
AMP, CEP, SXT
AMP, CEP, STR
AMC, AMP, FOX, TIO, CEP
IV ROUGH-O :- :-
AMC, AMP, FOX,
TIO, CEP, CHL, GEN,
STR, SMX, TCY, SXT
AMC, AMP, FOX,
TIO, CEP, CHL, GEN,
STR, SMX, TCY, SXT
a Raw food diet meals fed on Day 1 were Salmonella-negative
b Susceptible to all 16 tested antimicrobials
*Dogs returned to their normal diets of commercial dog food
**Not serotyped or tested for antimicrobial susceptibility
AMP = Ampicillin, AMC = Amoxicillin/Clavulanic Acid, CEP = Cephalothin, CHL = Chloramphenicol, FOX = Cefoxitin, GEN = Gentamicin, SMX = Sulfamethoxazole,
STR = Streptomycin, SXT = Trimethoprim/Sulphamethoxazole, TCY = Tetracycline, TIO = Ceftiofur
CVJ / VOL 48 / JANUARY 2007
a susceptible strain of S. Agona shed that strain plus a susceptible
strain of S. Tennessee and an S. Heidelberg strain resistant to
Our results showed that Salmonella infections tend to be non-
clinical and that shedding can occur for almost 2 wk following a
single meal in dogs not previously fed raw food diets. Although
no dogs became ill, they were easily colonized, if only transiently,
and therefore at risk of developing salmonellosis.
People who feed dogs commercial raw food diets should be
aware that the products are often contaminated with salmonellae
(24) and that dogs consuming them have a high probability of
shedding the organism. The shedding rate (44%) in this study
was higher than that (30%) observed by Joffe and Schlesinger
(19) in dogs fed homemade raw food diets. This difference may
have been due to the differences in length of time that dogs
were exposed to raw food diets in the 2 studies. The difference
may also have resulted if the total load of salmonellae present
in the commercial diets was greater than that in the homemade
diets. Determining this would have required a quantitative
measure of salmonellae organisms in the 2 types of diet, which
was not done in either study. However, one might expect the
microbial load to be lower in the commercial diets, since they
are frozen, a process that should kill some of the salmonellae
(25). Finally, the difference may simply have been a sample
size artefact. Sample sizes in both trials were relatively small,
and in this study, the 95% confidence interval for the shed-
ding rate (21%–69%) included the 30% found by Joffe and
In a previous study, the prevalence of Salmonella-contaminated
raw food diets in Calgary was 37% (20). Dogs in Calgary that
were fed these diets during the same time, therefore, could have
been exposed to salmonellae, on average, once every 3 feedings.
Our results indicated that dogs can shed salmonellae shortly
after ingestion of a single contaminated meal, with shedding
lasting up to 1.5 wk. The results of Joffe and Schlesinger’s trial
indicated that this shedding can be prolonged in dogs fed the
raw food diets over a longer period of time.
Clinical salmonellosis in dogs as a result of raw food diet
consumption has not been reported in the literature; however,
Siver et al (24) recently reported 2 cases of septicemic salmonel-
losis in cats fed raw food diets. Salmonellae were isolated from
several organs in both cats, and the isolates obtained from the
cats were identical to those isolated from raw beef that had been
incorporated into the diet of 1 of the cats. Salmonella Newport
originating from the meat used in their meals was found to be
the cause of death for both cats.
Salmonella Heidelberg was the most common serotype found
in positive diets, most of which contained chicken as the
main ingredient (Table 1). Salmonella Heidelberg was also the
most common serotype isolated from the feces of dogs in this
study. Results of a retail surveillance conducted in Canada in
2003, showed S. Heidelberg to be the most prevalent serovar
(73%) in 16% of chickens purchased from retail stores and
markets, followed by S. Kentucky (11%) (26). In Canada,
S. Heidelberg was the most common cause of human salmonel-
losis, accounting for 26% of all Salmonella isolates obtained from
human cases through enhanced passive surveillance in 2003.
Salmonella Typhimurium was the second most common sero-
type (25%) associated with human salmonellosis, followed by
S. Enteritidis (15%) (26). Public health officials should, there-
fore, ask about exposure to raw food diets and dogs that con-
sume these products when interviewing possible human cases of
Several isolates recovered from both the food samples and
the canine fecal samples were found to have different serotypes
and to carry different antimicrobial susceptibility patterns as
compared with the isolates from the corresponding raw food
samples. Two dogs were found to carry serotypes not recovered
from the raw food diet they received during the feeding trial.
Both of these dogs were in the same feeding trial group of
4 animals and received their contaminated portion of raw food
diet on the same morning at the same time. A possible explana-
tion for the apparent “cross-over” in serotypes that the 2 dogs
shed in their feces was that documentation of which diet was fed
to which dog was mixed up. Review of the data sheets yielded
no evidence of a recording error and all of the remaining fecal
shedding results were consistent with the documented dietary
Additional serotypes could have been present in the raw food
diets and not recovered despite the use of 3 methods and 3 selec-
tive media in parallel. Some dogs in the research colony from
which our trial dogs were sourced were apparently given pig
ear dog treats sometime prior to the feeding trial. Salmonellae
have been recovered from pig ear dog treats in the past (27,28);
however, recent retail sampling suggests the prevalence of
Salmonella contamination of pig ear treats sold in Ontario is
low (20). Three days of negative tests used for screening dogs
may not have been sufficient to completely rule out pretrial
Salmonella carriage. However, if prior exposure to pig ears was
the true source of Salmonella serotypes for dogs in our trial, we
would have expected some of the control dogs also to have shed
during the trial, which did not occur. The regular, heat processed
commercial food that was given to the trial dogs as their normal
diet was not a likely source, because all samples tested during
the feeding trial were negative for salmonellae.
Some Salmonella serotypes were more likely to be shed than
others. The majority of dogs that were fed raw food diets con-
taminated with S. Heidelberg and S. Infantis had Salmonella
isolates recovered from their fecal samples. However, dogs fed
raw food diets contaminated with S. Hadar and S. Meleagridis,
and some fed S. Infantis, S. Thompson, and S. Heidelberg, did
not shed salmonellae during the feeding trial period. It is pos-
sible that there really is a difference in the likelihood of shedding
related to serotype, which could be related to differences in
factors like inoculum size, survival in the frozen raw food diet
matrix, or ability to colonize the canine gut. It is also possible
that some of the Salmonella-negative dogs were false negatives,
either because the sampling frequency (once a day) was inad-
equate or because of methodological issues.
Antimicrobial resistance was similar in isolates recovered from
the raw food and the fecal isolates of the Salmonella-positive
dogs. One strain recovered from dog O’Henry was resistant
CVJ / VOL 48 / JANUARY 2007
to ampicillin, cephalothin, cefoxitin, and ceftiofur, which may
indicate that this isolate was an extended spectrum b-lactamase
producer. The source of the extra resistance is unclear; however,
transfer of genes from other bacteria, such as Escherichia coli is
a possibility. Testing of generic E. coli was also performed in
both food and canine fecal samples (data not shown). Generic
E. coli isolated from the food fed to O’Henry included resistance
to all 3 additional antimicrobials (data not shown). Resistance
genes can be transferred by viruses or taken up by bacteria
after another bacterium dies and releases its contents into the
environment (29). Although these mechanisms are possible,
transfer of resistance through conjugation is more likely (30).
Further investigation of the raw food samples and canine fecal
samples from this study will include an examination of the
antimicrobial susceptibility pattern of E. coli isolates. If there is
concordance between E. coli and Salmonella isolates, molecular
techniques will be used to investigate the possibility of exchange
of antimicrobial resistance genes between E. coli and Salmonella
in the dogs’ intestinal tracts.
To date, this is the 1st study conducted to investigate the
prevalence and antimicrobial resistance patterns of salmonellae
in dogs after consumption of Salmonella-contaminated commer-
cial raw food diets and the 1st study investigating the shedding
in dogs previously unexposed to raw food diets. It complements
and expands on the earlier study of homemade raw food diets
by Joffe and Schlesinger (19). As commercial raw food diets
are relatively new, one of the main unknowns is the number
of dogs currently consuming these products. Without these
data, it is difficult to estimate the risk to human and canine
populations. However, it is clear that dogs that eat Salmonella-
contaminated raw food diets can shed the bacteria, increasing
the risk of salmonellosis for dogs and dog owners. The diets
are a potential source of salmonellae resistant, in some cases, to
multiple antimicrobials, and to antimicrobials of importance
in human medicine, including third generation cephalosporins.
Furthermore, there is evidence, albeit unproven, of acquisition
of new resistance by salmonellae in the canine gut.
As the main objective of this study was to determine whether
or not dogs consuming Salmonella-contaminated raw food diets
would shed salmonellae, dogs enrolled in the study were not
followed after their 8th-consecutive Salmonella-negative fecal
sample. It is unknown how long Salmonella-positive dogs can go
between episodes of shedding. Anecdotally, 5 d of consecutive
negative tests has been thought sufficient to assume a negative
status. However, 1 dog at the end of the study was kept an
extra day in isolation because she could not be relocated on
the scheduled day. A Salmonella isolate was recovered on that
day, 9 d after the previous positive fecal sample. Future studies
should include a longer surveillance period to verify Salmonella-
Since this study was an experimental trial with laboratory
beagles, results may not be completely indicative of what would
be experienced with owned dogs of various breeds. Determining
that the raw food diet was the main source of salmonellae shed-
ding in owned dogs would be more complicated, as they could
be exposed to several other possible sources of salmonellae,
including other animals; other food items, including treats;
the environment; and their owners. There is also the need to
investigate the effects of multiple exposures to raw food diets
in dogs and to compare shedding in naïve dogs exposed to a
single meal with those exposed to multiple meals to determine
To minimize the risk of canine and human salmonellosis,
regulations governing the manufacture and sale of commercial
raw food diets should be established and enforced. Better labels
should be placed on packages containing commercial raw food
diets warning dog owners of the probability of the products
being contaminated with harmful bacteria. Organizations that
take dogs to seniors’ homes, long-term care hospitals, or other
hospital areas for therapeutic visits should not feed these diets,
because of the risks posed by bacterial pathogens and anti-
microbial resistant bacteria. Dog owners, especially those at
higher risk of developing acute salmonellosis, should be warned
about the risks of handling raw food diets.
We thank Nicol Janecko, Heather Lim, and all the labora-
tory staff for the help they provided with the microbiological
analysis of the samples and socialization of the dogs. We also
thank Dr. Anne Muckle, Betty Wilkie, Linda Cole, Andrea
Desruisseau, Ketna Mistry and Abigail Crocker at the Laboratory
for Foodborne Zoonoses, Public Health Agency of Canada for
the serotyping and antimicrobial susceptibility testing conducted
on the Salmonella isolates.
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Infectious Diseases of the Dog and Cat,
Greene CE. Elsevier, St. Louis, Missouri, USA, 2006, 1387 pp.
ISBN 1-4160-3600-8, US$199.
prehensive source of information on infectious diseases of the
dog and cat. Published 7 years after the previous version, the
3rd edition has incorporated a variety of pathogens that have
emerged or been recognized as of concern in dogs and cats
during this period.
The book is divided into sections on viral, rickettsial,
chlamydial, and mycoplasmal diseases; bacterial diseases; fun-
gal diseases; and protozoal diseases. There is also a large section
on clinical problems that addresses individual body systems,
plus other areas such as fever, prevention and management of
infectious diseases in different environments (i.e., multiple cat
environments, kennels), zoonoses, and immunoprophylaxis.
There are over 200 pages of appendices, covering topics such
as vaccination recommendations, laboratory testing, diagnostic
test kits, and formularies.
The accompanying CD contains full citations for all of the
references, but no additional material, and is not likely to be
frequently used by most individuals.
One of the strengths of this book is its comprehensive nature.
Almost all pathogens are covered under headings of etiology, epi-
he 3rd edition of this book builds on the strengths of
the previous edition and is undoubtedly the most com-
demiology, pathogenesis, clinical findings, diagnosis, pathologic
findings, therapy, and public health considerations. Important
issues regarding sample collection, diagnostic test selection,
and test interpretation are introduced at the beginning of the
major sections. There are numerous color images and tables that
complement the text; an improvement from the previous ver-
sion. Practical clinical information, including drug and dosage
recommendations, is readily available, often in clear tables.
As with most books, there are some factual errors that mostly
involve recent information and likely relate to the inherent lag
time from writing to publication. These are, in general, minor
and of little concern. One area, that may not receive adequate
attention relative to other topics, is the prudent use of antimi-
crobials. This is an important topic in veterinary medicine but
does not receive specific coverage. While certain section authors
mention the issue briefly, there is a lack of a comprehensive
overview of the subject. This concern is highlighted in Appendix
9, where various important human antimicrobials and recom-
mended uses are included, but there is little to no discussion
of prudent use.
Overall, this book is a very comprehensive guide to infectious
diseases of the dog and cat, and is a useful resource to the general
practitioner and specialist alike.
Reviewed by J Scott Weese, DVM, DVSc, DipACVIM, Associate
Professor, Department of Clinical Studies, Ontario Veterinary
College, University of Guelph, Guelph, Ontario N1G 2W1.
Compte rendu de livre