Objective—To determine risk factors associated with
hemorrhagic bowel syndrome (HBS) among dairy cattle
in the United States and identify characteristics of
HBS in individual cows.
Design—Cross-sectional, population-based survey.
Sample Population—A stratified random sample of
1,013 dairy operations with ≥ 30 cows located in 21
Procedure—Information on management and animal
health-related topics was collected with a questionnaire.
Results—HBS was estimated to have been observed
on 9.1% of operations during the preceding 5 years and
on 5.1% of operations during the preceding 12 months.
Factors found in multivariable analysis to be associated
with the occurrence of HBS during the preceding 12
months were large herd size, administration of bovine
somatotropin, and routine use of milk urea nitrogen
concentration to determine ration composition. Use of
pasture as part of the lactating cow ration during the
growing season was associated with decreased odds
of HBS in operations with rolling herd average milk production
≤ 20,000 lb, whereas in operations with higher
milk production, use of pasture was not associated with
occurrence of HBS. For individual cows with signs consistent
with HBS, the third lactation was the median of
the parity distribution and the median time between
parturition and the onset of clinical signs was 104 days.
Conclusions and Clinical Relevance—Results suggest
that management practices implemented to achieve
high milk production may increase the risk of developing
HBS in dairy cattle. Increased consumption of a high-energy
diet seems to be the most plausible common
pathway for all of the risk factors that have been
described. (J Am Vet Med Assoc 2005;226:1700–1706)
Objective—To determine clinicopathologic and radiographic
features and etiologic agents in cats that died
as a result of infectious pneumonia.
Procedure—Medical records of cats in which infectious
pneumonia was confirmed by histologic examination
of necropsy specimens were reviewed.
Signalment, clinical signs, and results of a CBC, viral
serologic tests, and thoracic radiography were evaluated.
Infectious agents were classified as bacterial,
viral, fungal, protozoal, or parasitic. Histologic features
(severity, duration, anatomic location, and distribution)
Results—Clinical signs referable to the respiratory
tract were not detected in 14 of 39 (36%) cats, and
results of a CBC (4/18 cats) and radiography (3/13)
were unremarkable. Sixteen of 39 (41%) cats lacked
clinical signs of systemic illness. Etiologic agents
identified included bacteria (n = 21), viruses (11), fungi
(6), protozoa (2), and parasites (1). Cats with clinical
signs related to the respiratory tract (19/24 [79%]
cats) were more likely to have severe histologic
changes than cats without signs related to the respiratory
system (6/14). Twenty-nine of 38 (76%) cats
had histologic evidence of systemic disease, whereas
the remaining cats had lesions limited to the respiratory
Conclusions and Clinical Relevance—Infectious
pneumonia is uncommon in cats. Cats with infectious
pneumonia may lack clinical signs and have
unremarkable results for a CBC and thoracic radiography,
yet frequently have systemic infections.
Therefore, clinicians should maintain an index of suspicion
for pneumonia and evaluate the respiratory
tract when infection is detected in other organ systems.
(J Am Vet Med Assoc 2003;223:1142–1150)
Objective—To compare the effects of an orally administered
corticosteroid (prednisone), an inhaled corticosteroid
(flunisolide), a leukotriene-receptor antagonist
(zafirlukast), an antiserotonergic drug (cyproheptadine),
and a control substance on the asthmatic phenotype
in cats with experimentally induced asthma.
Animals—6 cats with asthma experimentally
induced by the use of Bermuda grass allergen (BGA).
Procedures—A randomized, crossover design was
used to assess changes in the percentage of
eosinophils in bronchoalveolar lavage fluid (BALF); airway
hyperresponsiveness; blood lymphocyte phenotype
determined by use of flow cytometry; and serum
and BALF content of BGA-specific IgE, IgG, and IgA
determined by use of ELISAs.
Results—Mean ± SE eosinophil percentages in BALF
when cats were administered prednisone (5.0 ±
2.3%) and flunisolide (2.5 ± 1.7%) were significantly
lower than for the control treatment (33.7 ± 11.1%).
We did not detect significant differences in airway
hyperresponsiveness or lymphocyte surface markers
among treatments. Content of BGA-specific IgE in
serum was significantly lower when cats were treated
with prednisone (25.5 ± 5.4%), compared with values
for the control treatment (63.6 ± 12.9%); no other
significant differences were observed in content of
BGA-specific immunoglobulins among treatments.
Conclusions and Clinical Relevance—Orally administered
and inhaled corticosteroids decreased
eosinophilic inflammation in airways of cats with
experimentally induced asthma. Only oral administration
of prednisone decreased the content of BGAspecific
IgE in serum; no other significant local or systemic
immunologic effects were detected among
treatments. Inhaled corticosteroids can be considered
as an alternate method for decreasing airway
inflammation in cats with asthma. (Am J Vet Res
Objective—To evaluate changes in cysteinyl
leukotriene (LT) concentrations in urine and bronchoalveolar
lavage fluid (BALF) in cats with experimentally
Animals—19 cats with experimentally induced asthma
and 5 control cats.
Procedure—Cats were sensitized to Bermuda grass
or house dust mite allergen, and phenotypic features
of asthma were confirmed with intradermal skin testing,
evaluation of BALF eosinophil percentages, and
pulmonary function testing. A competitive ELISA kit
for LTC4, LTD4, and LTE4 was used for quantitative
analysis of LTs. Urinary creatinine concentrations and
BALF total protein (TP) concentrations were measured,
and urinary LT-to-creatinine ratios and BALF LTto-
TP ratios were calculated.
Results—Mean urinary LT-to-creatinine ratios did not
differ significantly between control cats and allergensensitized
cats before or after sensitization and challenge
exposure with saline (0.9% NaCl) solution or
allergen, respectively. In BALF, the mean LT-to-TP ratio
of control cats did not differ significantly before or
after sensitization and challenge exposure with saline.
Asthmatic cats had BALF LT-to-TP ratios that were
significantly lower than control cats at all time points,
whereas ratios for asthmatic cats did not differ significantly
among the various time points.
Conclusions and Clinical Relevance—Although
LTs were readily detectable in urine, no significant
increases in urinary LT concentrations were
detected after challenge in allergen-sensitized
cats. Spot testing of urinary LT concentrations
appears to have no clinical benefit for use in monitoring
the inflammatory asthmatic state in cats.
The possibility that cysteinyl LTs bind effectively to
their target receptors in BALF and, thus, decrease
free LT concentrations deserves further study.
(Am J Vet Res 2003;64:1449–1453)
Objective—To identify risk factors associated with
dysautonomia in dogs.
Animals—42 dogs with dysautonomia examined
between October 1988 and January 2000 and 132
control dogs examined during the same period for an
Procedure—Information was gathered from medical
records and surveys mailed to owners of case and
Results—42 case and 132 control dogs were included;
completed surveys were returned by owners of
30 case and 103 control dogs. Dogs with dysautonomia
were significantly younger (median, 18 months)
than control dogs (median, 60 months) and more likely
to come from rural areas and to spend ≥ 50% of
their time outdoors. Compared with rural control dogs
that spent at least some time outdoors, affected dogs
were more likely to have access to pasture land, farm
ponds, and cattle, and to have consumed wildlife, at
least occasionally. The largest numbers of dogs with
dysautonomia were identified during February and
April, with relatively few dogs identified during the
summer and early fall.
Conclusion and Clinical Relevance—Although the
cause of dysautonomia is unknown, results suggest
that dogs with dysautonomia were significantly more
likely to live in rural areas and spend ≥ 50% of their
time outdoors than were control dogs examined for
unrelated diseases. (J Am Vet Med Assoc 2001;218:
Objective—To investigate whether expression of inflammation-associated genes in leukocytes from horses with gastrointestinal tract (GIT) diseases correlated with the type of disease and outcome.
Animals—10 healthy horses and 50 horses with GIT disease.
Procedures—A blood sample was collected from each healthy horse or horse with GIT disease (during admission to the hospital). Leukocytes were isolated, diluted to a standard concentration, and frozen until RNA extraction. Expression of 14 genes associated with inflammation was quantified by use of a real-time quantitative reverse transcription PCR assay. Results were grouped by GIT disease type and disease outcome for comparison.
Results—Horses with GIT disease had colic of unknown etiology (n = 8 horses), GIT inflammation or strangulation (19), or nonstrangulating GIT obstruction (23). Among the 45 horses receiving treatment, 38 were discharged from the hospital, and 7 died or were euthanized. Compared with healthy horses, horses with colic of unknown etiology had similar gene expression. Significant differences in expression of the interleukin-8, leukocyte-selectin molecule, matrix metalloproteinase-9, platelet-selectin molecule, mitochondrial superoxide dismutase, Toll-like receptor 4, and tumor necrosis factor-A genes were detected between healthy horses and horses with GIT disease. Significant differences in expression of the interleukin-1 receptor antagonist, interleukin-8, leukocyte-selectin molecule, matrix metalloproteinase-9, platelet-selectin molecule, mitochondrial superoxide dismutase, Toll-like receptor 4, and tumor necrosis factor-A genes were detected among healthy horses and horses grouped by disease outcome.
Conclusions and Clinical Relevance—Inflammatory gene expression in leukocytes of horses with GIT disease appeared to be related to disease pathogenesis and prognosis.
Objective—To investigate the effect of ex vivo exposure to lipopolysaccharide (LPS) on the expression of inflammatory genes in leukocytes from horses with gastrointestinal (Gl) disease and determine whether the pattern or magnitude of the response to LPS correlated with the type of disease and outcome.
Animals—49 horses with Gl disease and 10 healthy horses
Procedures—Leukocytes were isolated from blood samples and submitted to 3 protocols: immediate freezing, freezing after 4-hour incubation in medium, and freezing after 4-hour incubation in medium containing LPS. Expression of 14 genes associated with inflammation was assessed via PCR assay. Results were compared by disease type and outcome
Results—Horses with Gl disease had colic of unknown etiology (n = 8), Gl inflammation or strangulation (18), or nonstrangulating Gl obstruction (23). Among the 44 horses receiving treatment, 38 were discharged from the hospital and 6 died or were euthanized. Incubation of leukocytes in medium alone changed the expression of several genes. Incubation with LPS resulted in increased expression of interleukin-10 and monocyte chemotactic protein-3 in leukocytes from healthy and sick horses. Leukocytes from horses with nonstrangulating obstruction and horses that survived had less pronounced LPS-induced increases in interleukin-10 expression than did cells from healthy horses. The opposite was evident for monocyte chemotactic protein-3.
Conclusions and Clinical Relevance—No evidence existed for a reduced response of leukocytes from horses with gastrointestinal disease to ex vivo exposure to LPS. Leukocyte expression of inflammatory genes after ex vivo incubation with LPS appeared to be related to pathogenesis and prognosis. (Am J Vet Res 2010;71:1162—1169)
Objective—To determine whether the presence of Chlamydophila psittaci antigen, plasma cholesterol concentration, diet, sex, species, and age are risk factors for the development of atherosclerosis in pet psittacine birds.
Design—Retrospective case-control study.
Animals—31 psittacine birds with atherosclerosis (study birds) and 31 psittacine birds without atherosclerosis (control birds).
Procedures—Necropsy reports were reviewed, birds with a histopathologic diagnosis of atherosclerosis were identified, and available medical records were reviewed. Signalment, history, clinicopathologic findings, and other relevant data were recorded and evaluated. Control birds did not have atherosclerosis and were chosen by both convenience sampling and population demographics. Histologic sections of great vessels from all birds (study and control birds) were reviewed and then submitted for immunohistochemical staining for the presence of C psittaci antigen.
Results—Result of immunohistochemical staining for C psittaci antigen in blood vessels was significantly associated with atherosclerosis. After adjusting for age, species origin, and type of illness, the odds of atherosclerosis was 7 times as high for birds with positive immunohistochemical staining for C psittaci antigen, compared with that of birds with negative immunohistochemical staining. Study birds and control birds differed significantly only with respect to plasma cholesterol concentrations. The median plasma cholesterol concentration of study birds (421 mg/dL) was significantly higher than that of control birds (223 mg/dL).
Conclusions and Clinical Relevance—Infection with C psittaci and a high plasma cholesterol concentration may be risk factors for developing atherosclerosis in pet psittacine birds.
Objective—To evaluate the incidence of colic and risk factors for colic in equids hospitalized for ocular disease.
Design—Retrospective observational study.
Animals—337 equids (317 horses, 19 ponies, and 1 donkey) hospitalized for ocular disease.
Procedures—Medical records of equids hospitalized for > 24 hours for treatment of ocular disease between January 1997 and December 2008 were reviewed. Information from only the first hospitalization was used for equids that were hospitalized for ocular disease on more than 1 occasion. Information gathered included the signalment, the type of ocular lesion and the treatment administered, and any colic signs recorded during hospitalization as well as the severity, presumptive diagnosis, and treatment of the colic. Statistical analysis was used to identify any risk factors for colic in equids hospitalized for ocular disease.
Results—72 of 337 (21.4%) equids hospitalized for ocular disease had signs of colic during hospitalization. Most equids (59.7% [43/72]) had mild signs of colic, and most (87.5% [63/72]) were treated medically. Ten of 72 (13.9%) equids with colic had a cecal impaction. Risk factors for colic in equids hospitalized for ocular disease were age (0 to 1 year and ≥ 21 years) and an increased duration of hospitalization (≥ 8 days).
Conclusions and Clinical Relevance—There was a high incidence of colic in equids hospitalized with ocular disease in this study. Findings from this study may help identify equids at risk for development of colic and thereby help direct implementation of prophylactic measures.
Objective—To compare immune responses following modified-live virus (MLV) vaccination at weaning after intranasal or SC administration of an MLV vaccine to beef calves at 2 or 70 days of age.
Procedures—Calves were allocated to 1 of 5 groups. The IN2 (n = 37) and IN70 (37) groups received an MLV vaccine containing bovine herpesvirus 1 (BHV1), bovine viral diarrhea virus (BVDV) types 1 and 2, bovine respiratory syncytial virus (BRSV), and parainfluenza 3 virus intranasally and a Mannheimia haemolytica and Pasteurella multocida bacterin SC at median ages of 2 and 70 days, respectively. The SC2 (n = 36) and SC70 (37) groups received a 7-way MLV vaccine containing BHV1, BVDV1, BVDV2, BRSV, parainfluenza 3 virus, M haemolytica, and P multocida SC at median ages of 2 and 70 days, respectively; the control group (37) remained unvaccinated until weaning. All calves received the 7-way MLV vaccine SC at median ages of 217 (weaning) and 231 days. Serum neutralizing antibody (SNA) titers against BHV1, BVDV1, and BRSV and intranasal IgA concentrations were determined at median ages of 2, 70, 140, 217, and 262 days. Cell-mediated immunity (CMI) against BHV1, BRSV, BVDV1, and P multocida was determined for 16 calves/group.
Results—At median ages of 140 and 217 days, BVDV1 SNA titers were significantly higher for the SC70 group than those for the other groups. Intranasal IgA concentrations and CMI increased over time for all groups. Vaccination at weaning increased SNA titers and CMI in all groups.
Conclusions and Clinical Relevance—SC administration of an MLV vaccine to 70-day-old calves significantly increased BVDV1 antibody titers before weaning.