Objective—To evaluate the potential of excess
dietary iron to cause hepatic lesions similar to those
described in horses with suspected iron toxicosis or
Animals—6 adult male ponies.
Procedure—4 ponies received 50 mg of iron/kg (22.7
mg/lb) of body weight each day by oral administration
of ferrous sulfate, which contained 20% elemental
iron; 2 ponies received only the carrier (applesauce).
Complete blood counts, serum biochemical analyses,
and hepatic tissue biopsies were performed, and
serum iron concentrations were measured. Blood and
tissue samples were obtained at days 0 and 2, and at
the end of weeks 1, 3, 6, and 8 after administration of
iron was initiated. Treatment was discontinued after 8
weeks, and hepatic iron concentrations were measured
at 28 weeks.
Results—Hepatic iron concentrations, serum iron
concentrations, percentage saturation of transferrin,
and serum ferritin concentrations were increased,
compared with baseline and control concentrations,
by week 8. Adverse clinical signs or histologic lesions
in the liver were not detected in any ponies. At 28
weeks, hepatic iron concentrations had decreased.
Conclusions and Clinical Relevance—Histologic
lesions were not seen in the hepatic biopsy specimens
obtained from the ponies treated with ferrous
sulfate. It was concluded that it would be unlikely for
iron toxicosis to develop in adult ponies or horses during
a period of < 8 weeks when food or water contained
increased amounts of iron. It is suspected that
previous reports of hepatopathies in animals with
hemosiderin accumulation may represent a primary
hepatopathy with secondary hemosiderin accumulation,
especially if the only source of iron is via oral
consumption. (J Am Vet Med Assoc 2001;218:
Objective—To determine whether a nonionic detergent
(Triton WR 1339) can be used in cats to assess
hepatic secretion of triglyceride.
Animals—28 healthy cats.
Procedure—Triton WR 1339 was administered IV
according to the following schedule: 5, 50, 150, and
250 mg/kg of body weight. Control cats did not
receive an injection or received 0.9% NaCl or PBS
solutions at the same osmolarity and volume as the
250 mg/kg group. Blood samples were collected
throughout the 48-hour period after administration for
determination of triglyceride and cholesterol concentrations
and for RBC morphology and osmotic fragility
Results—Administration of Triton WR 1339 at 150
and 250 mg/kg caused profound hypertriglyceridemia.
Triglyceride concentrations increased in a
curvilinear fashion for the first 2 hours and remained
increased for approximately 24 hours. Area under the
time-concentration curve for triglyceride at 5 hours
differed significantly among groups. At 12 and 24
hours, cholesterol was significantly higher in cats
receiving 250 mg/kg. The most dramatic changes in
osmotic fragility and RBC morphology were in cats
receiving 250 mg/kg; 1 of these cats developed
severe icterus and died 5 days later. Feeding rice and
casein before administering Triton WR 1339 at 150
mg/kg did not appear to affect the hypertriglyceridemia
Conclusions and Clinical Relevance—Triton WR 1339
can be administered IV to cats at a rate of 150 mg/kg to
assess hepatic triglyceride secretion, although some
cats may have increased RBC osmotic fragility. Higher
dosages caused substantial adverse effects, whereas
lower dosages did not alter plasma triglyceride concentration.
(Am J Vet Res 2000;61:941–950)
Objective—To develop a method for inducing acute
leptospirosis in dogs.
Animals—31 nine-week-old female Beagles.
Procedure—Beagles were randomly assigned to 2
inoculation groups or a control group. Dogs were
inoculated on 3 successive days by conjunctival instillation
of 5 X 107 cells of Leptospira kirschneri serovar
grippotyphosa strain 82 (12 dogs) or strain RM 52 (14
dogs). Control dogs (n = 5) were similarly inoculated
with sterile leptospiral culture media. Clinical signs,
clinicopathologic variables, anti-leptospiral antibody
titers, and evidence of leptospires in tissues and body
fluids were evaluated. Dogs were euthanatized and
necropsied on days 7, 14, 22, or 28 after inoculation or
as required because of severe illness.
Results—Clinical signs in infected dogs included conjunctivitis,
lethargy, diarrhea, dehydration, vomiting,
and icterus. Consistent clinicopathologic alterations
included azotemia, hyperphosphatemia, increased
anion gap, hyperbilirubinemia, and an increase in alkaline
phosphatase activity. Leptospires were cultured
from the kidneys (11/12), urine (6/9), aqueous humor
(9/12), blood (12/12), and liver (12/12) of dogs inoculated
with strain 82. Only 3 of 14 dogs became infected
after inoculation with strain RM 52.
Histopathologic lesions in infected dogs included
interstitial nephritis, renal tubular degeneration and
necrosis, pulmonary hemorrhage, and hepatic edema
Conclusions and Clinical Relevance—Conjunctival
exposure to L kirschneri serovar grippotyphosa strain
82 resulted in acute leptospirosis in all inoculated
dogs, but only 3 of 14 dogs inoculated with strain RM
52 became infected. This method of infection by
serovar grippotyphosa can be used to study the
pathogenesis and prevention of leptospirosis in dogs.
(Am J Vet Res 2004;65:1100–1107)
Objectives—To determine effects of selectin inhibitor
TBC1269 on neutrophil infiltration, and neutrophilassociated
injury during pneumonia induced by
Mannheimia haemolytica and concentration of antimicrobial
anionic peptide (AAP) in bronchoalveolar
lavage fluid (BALF) as well as antimicrobial activity of
BALF from healthy (control) neonatal calves, neonatal
calves with M haemolytica-induced pneumonia,
neonatal calves with prior treatment with TBC1269,
and adult cattle.
Animals—Eighteen 1- to 3-day-old calves and 9 adult
Procedure—Calves were inoculated with M
haemolyticaor pyrogen-free saline (0.14M NaCl) solution
into the right cranial lung lobe, and BALF was collected
2 or 6 hours after inoculation. Thirty minutes
before and 2 hours after inoculation, 4 calves received
TBC1269. The BALF collected from 9 adult cattle was
used for comparison of BALF AAP concentration and
antimicrobial activity. Protein concentration and neutrophil
differential percentage and degeneration in
BALF were determined. An ELISA and killing assay
were used to determine BALF AAP concentration and
antimicrobial activity, respectively.
Results—Total protein concentration was significantly
decreased in BALF from calves receiving TBC1269.
Similar concentrations of AAP were detected in BALF
from all calves, which were 3-fold higher than those in
BALF from adult cattle. However, BALF from
neonates had little or no anti-M haemolytica activity.
Conclusions and Clinical Relevance—These results
suggest that TBC1269 decreases pulmonary tissue
injury in neonatal calves infected with M haemolytica.
Although AAP is detectable in neonatal BALF at 3
times the concentration detected in adult BALF,
neonatal BALF lacks antimicrobial activity for M
haemolytica. (Am J Vet Res 2001;62:665–672)
Objective—To evaluate gross, histopathologic, and
serum biochemical findings caused by Leptospira
interrogans serovars pomona and bratislava inoculated
Animals—Twenty-seven 8-week-old female Beagles.
Procedure—Dogs were randomly assigned to challenge
or control groups. Challenge groups were conjunctivally
inoculated on 3 successive days with
5 ×107L interrogans serovar pomona (n = 12) or
serovar bratislava (11). Clinical signs were recorded
throughout the experiment, and clinical pathology
assays, bacteriologic culture, and necropsies (6 or 7
dogs necropsied at each time point) were done on
postinoculation day (PID) 7, 10, 14, and 20.
Results—Infection could not be confirmed in any
serovar bratislava–inoculated dog, and control dogs
remained healthy throughout the experiment.
Positive culture and fluorescent antibody test results
were confirmed in 11 of 12 serovar pomona–inoculated
dogs. Fever and lethargy starting at PID 7 were
the most common clinical signs in serovar
pomona–infected dogs. On day 10, gross lesions
included multifocal renal and pulmonary hemorrhage
and perirenal edema. Serovar pomona–inoculated
dogs had histopathologic lesions including hepatitis,
interstitial nephritis, and pneumonia at PID 7, 10, 14,
and 20. Increases in BUN, anion gap, and bilirubin
concentration occurred on PID 10, 14, and 20.
Platelet counts in dogs with positive results of bacteriologic
culture were decreased from baseline values
on PID 10, 12, and 14.
Conclusions and Clinical Relevance—
Conjunctival inoculation with L interrogans serovar
pomona resulted in a high rate of infection with concomitant
hemorrhagic and inflammatory lesions of
the kidneys, liver, and lungs. (Am J Vet Res
Objective—To compare the ease and effects of collecting blood from cats by use of subcutaneous totally implantable vascular access ports (VAPs) with collection via conventional jugular phlebotomy.
Design—Prospective randomized experimental study.
Animals—8 healthy cats.
Procedures—Cats in the port group (n = 4) underwent monthly blood donation by use of VAPs and manual restraint, and cats in the nonport group (4) underwent monthly blood donation by use of conventional jugular phlebotomy and sedation, for 6 months.
Results—Postsurgical VAP-related complications developed in 3 cats and included port erosion (n = 1), disconnection of the port from the catheter (1), and seroma formation (1). Blood was successfully collected 24 of 24 and 20 of 20 times in the nonport and port groups, respectively. Results of bacterial culture of blood were negative in 22 of 24 and 15 of 20 nonport and port collections, respectively. No differences in RBC morphology were observed between groups. Mean blood collection and total donation times were significantly longer for the nonport group. Collection time was more variable in the nonport group, and cats were less tolerant of handling during venipuncture, compared with cats in the port group. Blood collection required a mean of 2.4 persons for the nonport group and 2.1 persons for the port group.
Conclusions and Clinical Relevance—Positive results for blood collections via VAPs were increased donor acceptance, decreased number of personnel required, and decreased collection time. Drawbacks included contamination of blood products and port-related complications.