Objective—To determine relationships between fecal
consistency and colonic microstructure and absorptive
function in dogs with and without nonspecific
Animals—12 dogs with nonspecific dietary sensitivity
(affected) and 9 healthy dogs (controls).
Procedure—Affected dogs were fed 4 test diets and
control dogs, 3 diets for 4 weeks each in a crossover
design. Fecal consistency was assessed daily. At the
end of each feeding period, electrolyte and water
transport were assessed, and colonic biopsy specimens
were obtained for histologic examination and
measurement of crypt water uptake by use of confocal
Results—Feces were consistently looser in affected
dogs. In control dogs, we detected net colonic
absorption of sodium and chloride and secretion of
potassium and bicarbonate. Absorption of sodium
and chloride was less in affected dogs, compared
with controls, indicating that electrolyte transport was
disrupted in affected dogs. This disruption was accentuated
during feeding of diets associated with significantly
poorer fecal consistency (ie, loose feces). Fecal
consistency was inversely correlated with crypt water
absorption, which was reduced in affected dogs.
Colonic crypts were shorter and less dense in affected
dogs fed diets associated with poor fecal consistency,
compared with affected dogs fed other diets or
with control dogs.
Conclusions and Clinical Relevance—Colonic transport
function is a major determinant of fecal consistency
in dogs. Dogs with nonspecific dietary sensitivity
are particularly susceptible to diet-induced
changes in absorptive function. Such changes are
associated with damage to colonic microstructure,
disrupted electrolyte transport, and failure to dehydrate
luminal contents. (Am J Vet Res 2002;
Objective—To determine effects of oral administration
of metronidazole on the number and species of
duodenal bacteria and selective nutrients of cats.
Animals—6 healthy domestic shorthair cats.
Procedure—Undiluted duodenal fluid was obtained
for quantitative and qualitative bacterial culture to
determine species and number of bacteria in healthy
cats. Blood samples were assayed for taurine, total
protein, albumin, cobalamin, and folate concentrations.
Cats then were given metronidazole (20 mg/kg
of body weight, PO, q 12 h) for 1 month, after which
bacterial cultures and serum assays of nutrients were
repeated. Nine months after cessation of antibiotic
treatment, duodenal bacteria were re-evaluated and
serum was assayed for total protein, albumin, cobalamin,
and folate concentrations.
Results—Oral administration of metronidazole
caused a significant decrease in aerobic and anaerobic
bacterial counts in the duodenum of healthy cats,
accompanied by emergence of Streptococcus spp
and Corynebacterium spp. Serum concentrations of
cobalamin and albumin increased when duodenal
bacterial counts were decreased, although changes in
folate or taurine concentrations were not detected.
Measured variables did not differ, when comparing
results obtained before and 9 months after cessation
Conclusions and Clinical Relevance—Oral administration
of metronidazole decreased the number of
aerobic bacteria and altered indigenous flora in the
small bowel of cats. Normal duodenal flora appeared
to be stable, because species of bacteria were reestablished
by 9 months after cessation of metronidazole.
Bacterial flora appeared to have an impact
on nutrients, because albumin and cobalamin
increased during antibiotic administration and
returned to preadministration concentrations after
cessation of the antimicrobial. (Am J Vet Res
Objective—To evaluate intestinal permeability and
absorption in healthy cats in association with diet and
normal intestinal microflora.
Animals—6 healthy domestic shorthair cats.
Procedure—A sugar solution containing D-xylose, 3-
0-methyl-D-glucose, L-rhamnose, lactulose, and 51Cr-
EDTA was administered intragastrically to healthy
cats, and urinary excretion of ingested sugars was
determined 5 hours after administration. After the
same cats had received metronidazole for 1 month,
the study was repeated. A final study was performed
while cats were maintained on a new diet differing in
composition and processing.
Results—Lactulose-to-rhamnose ratios, reflecting
intestinal permeability, were higher in cats, compared
with values for humans or dogs, and values obtained
before and after metronidazole administration (mean
± SEM; before, 0.40 ± 0.08; after, 0.45 ± 0.09) were
not significantly different. Intestinal absorption also
was unaltered after antibiotic administration, and the
xylose-to-glucose ratio was 0.70 ± 0.03 before and
0.71 ± 0.06 after metronidazole administration. Sugar
recovery did not differ significantly while cats were
maintained on canned or dry food.
Conclusions and Clinical Relevance—Reference
ranges were established for the percentage urinary
recovery of orally administered D-xylose, 3-0-methyl-Dglucose,
L-rhamnose, lactulose, and 51Cr-EDTA
obtained after 5 hours in healthy cats. The intestines of
cats appear to be more permeable than those of other
species, although the normal bacterial microflora does
not appear to influence the integrity or function of the
feline intestine, because values obtained for the measured
variables before or after antibiotic administration
were not significantly different. In addition, differences
were not detected when the diet was completely
altered. ( Am J Vet Res 2001;62:111–118)
Objective—To develop a noninvasive method for the
in vivo assessment of flatulence in dogs.
Animals—8 adult dogs.
Procedure—Rectal gases were collected via a perforated
tube held close to each dog's anus and attached
to a monitoring pump fitted with a sensor that recorded
hydrogen sulfide concentrations every 20 seconds.
Patterns of flatulence were monitored for 14
hours after feeding on 4 days, and within- and
between-dog variation was assessed over 4 hours on
4 consecutive days. Rate of hydrogen sulfide production
(flatulence index) and frequency and number of
emissions were evaluated as potential indicators of
flatus characteristics. An odor judge assigned an odor
rating to each flatulence episode, and the relationship
between that rating and hydrogen sulfide concentration
Results—Flatulence patterns varied within and
between dogs. Variation was most pronounced for flatulence
index; mean coefficients of variance within
dogs over time and between dogs on each day were
75 and 103%, respectively. Flatus with hydrogen sulfide
concentrations > 1 parts per million could be
detected by the odor judge, and severity of malodor
was highly correlated with hydrogen sulfide concentration.
Odor ratings were accurately predicted by use of
the equation 1.51 × hydrogen sulfide concentration0.28.
Conclusions and Clinical Relevance—The technique
described in this report appears to provide sensitive,
reliable, and relevant data and will enable further
studies of the factors that influence flatulence in
dogs. Use of this technique also has the potential to
aid in investigations of colonic physiology and pathology.
(Am J Vet Res 2001;62:1014–1019).
Objective—To establish a model for inheritance of
gluten-sensitive enteropathy (GSE) in Irish Setters.
Animals—44 dogs of a 6-generation family of Irish
Setters with GSE and 7 healthy Irish Setters.
Procedure—Phenotype of each dog was determined
after oral administration of gluten in the weaning diet,
using morphometric evaluation of jejunal biopsies (all
generations) and measurement of small intestinal
permeability by use of a lactulose-rhamnose permeation
test (generations 1, 2, and 3). Overall probability
for each of 4 genetic models of inheritance (autosomal
recessive, autosomal dominant, sex-linked recessive,
and sex-linked dominant) accounting for segregation
of partial villus atrophy within the entire family
Results—The autosomal recessive model was most
tenable and was 56,250 times more likely to
account for segregation of partial villus atrophy than
the autosomal dominant model, assuming disease
prevalence of 0.8%. Both sex-linked models were
untenable. These conclusions were robust to the
error attached to estimation of disease prevalence.
High intestinal permeability without morphometric
jejunal abnormalities in 4 of 20 dogs in the 3
youngest generations suggested heterogeneity of
lesions associated with GSE.
Conclusions—Genetic transmission of GSE is under
the control of a single major autosomal recessive
locus. (Am J Vet Res 2000;61:462–468)
Objective—To determine whether feeding activated
charcoal, Yucca schidigera, and zinc acetate would
ameliorate the frequency and odor characteristics of
flatulence in dogs.
Design—In vitro screening of active agents followed
by a randomized controlled trial.
Animals—8 adult dogs.
Procedure—A fecal fermentation system was used
to assess the effects of activated charcoal, Yucca
schidigera, and zinc acetate alone and in combination
on total gas production and production of hydrogen
sulfide, the primary determinant of flatus malodor in
dogs. All 3 agents were subsequently incorporated
into edible treats that were fed 30 minutes after the
dogs ate their daily rations, and the number, frequency,
and odor characteristics of flatulence were measured
for 5 hours, using a device that sampled rectal
gases and monitored hydrogen sulfide concentrations.
Results—Total gas production and number and frequency of flatulence episodes were unaffected by any
of the agents. Production of hydrogen sulfide in vitro
was significantly reduced by charcoal, Yucca schidigera,
and zinc acetate by 71, 38, and 58%, respectively,
and was reduced by 86% by the combination of
the 3 agents. Consumption of the 3 agents was associated
with a significant decrease (86%) in the percentage
of flatulence episodes with bad or unbearable
odor and a proportional increase in the percentage
of episodes of no or only slightly noticeable odor.
Conclusions and Clinical Relevance—Results suggest that activated charcoal, Yucca schidigera, and
zinc acetate reduce malodor of flatus in dogs by altering
the production or availability of hydrogen sulfide in
the large intestine. (J Am Vet Med Assoc 2001;218:
Objective—To determine whether a colony environment predisposes healthy cats to high bacterial counts, including counts of obligate anaerobes, in the duodenum and whether increased numbers of bacteria could be found in the duodenum of cats with signs of chronic gastrointestinal tract disease.
Animals—20 healthy control cats (10 from a colony environment and 10 pet cats) and 19 cats with a history of chronic gastrointestinal tract disease.
Procedure—Undiluted duodenal fluid was quantitatively and qualitatively assessed by bacteriologic culture under aerobic and anaerobic conditions. Serum concentrations of cobalamin and folate were also measured.
Results—Significant differences were not detected in the numbers of bacteria found in the duodenum of cats housed in a colony environment, compared with pet cats fed an identical diet prior to sampling. All healthy cats were, therefore, combined into 1 control group. Compared with healthy cats, cats with clinical signs of gastrointestinal tract disease had significantly lower counts of microaerophilic bacteria, whereas total, anaerobic, and aerobic bacterial counts were not significantly different. None of the cats with disease had total bacterial counts higher than expected from the range established in the control cats. Differences were not detected in regard to serum folate or cobalamin concentrations between diseased and healthy cats.
Conclusions and Clinical Relevance—These findings indicated that healthy colony cats and pet cats have high numbers of bacteria in the duodenum, including high numbers of obligate anaerobes. Our findings also suggest that bacterial overgrowth in the small intestine is not a common clinical syndrome in cats with chronic nonobstructive gastrointestinal tract disease. ( J Am Vet Med Assoc 2001;218:48–51)