Objective—To compare the efficacy of a Salmonella
bacterin and a modified live Salmonella ser.
Choleraesuis vaccine on a commercial dairy.
Animals—450 cows in late gestation and 80 calves.
Procedure—Group-1 cows (n = 150) were vaccinated
once with a modified live S Choleraesuis (serogroup
C1) strain 54 (SC54) vaccine, group-2 cows (150) were
vaccinated on enrollment and 30 days later with a
Salmonella ser. Montevideo (serogroup C1) bacterin,
and group-3 cows (150) served as unvaccinated controls.
One gallon of colostrum harvested from the first
80 cows to calve was fed to each calf. Outcome
assessments included fecal shedding of Salmonella
spp for the first 10 days after parturition (cows) or birth
(calves), milk production, involuntary culling rate, mastitis
incidence, antimicrobial use, and mortality rate.
Results—Salmonellae were isolated from 306 of 309
(99%) cows and 64 of 74 (86.5%) calves. Shedding
frequency was less in SC54-vaccinated cows and
calves that received colostrum from those cows,
compared with the other groups, and vaccination was
specifically associated with less shedding of
serogroup C1 salmonellae. Production data were similar
Conclusions and Clinical Relevance—Vaccination of
pregnant cows with an autogenous Salmonella bacterin
had no effect on fecal shedding of salmonellae,
whereas vaccination with a modified live
S Choleraesuis vaccine reduced the frequency of
fecal shedding of serogroup C1 salmonellae during
the peripartum period. A commercial S Choleraesuis
vaccine licensed for use in swine may be more efficacious
than autogenous Salmonella bacterins on
dairies infected with serogroup C1 salmonellae. (Am
J Vet Res 2001;62:1897–1902)
Objective—To evaluate the efficacy of ceftiofur crystalline-
free acid (CCFA) administered into the posterior
aspect of an ear for treatment of corneal ulceration
associated with naturally occurring infectious bovine
Animals—78 beef calves located at Sierra Foothills
Field Station (SFS) and 52 calves located at a commercial
dairy (CD). All calves were from 3 to 9
Procedure—At each site, calves were randomly allocated
to 1 of 2 treatment groups by use of a block
design determined by corneal ulcer size. A single
dose of CCFA (6.6 mg of ceftiofur equivalents/kg, SC)
was administered into the posterior aspect of a pinna.
A second group of calves received a single dose of
vehicle (0.03 mL/kg, SC; controls). Corneal ulcers
were photographed, and clinical signs were assessed
in calves every 3 to 4 days for 21 days.
Results—A positive treatment effect was detected
at SFS. Results at the CD were inconclusive
because ulcer healing occurred rapidly in control and
CCFA-treated calves. At SFS, treatment with CCFA
resulted in shorter mean healing times, smaller
corneal ulcer surface area measurements, amelioration
of ocular discharge and photophobia, and a 50%
increase in the percentage of calves healed by day
14. After adjustment for initial corneal ulcer size,
treatment with CCFA resulted in a 4-fold increase in
the odds of corneal ulcer healing by day 14, compared
Conclusions and Clinical Relevance—A single dose
of CCFA administered into the posterior aspect of a
pinna had a positive treatment effect against naturally
occurring IBK in calves with corneal ulcerations . (Am J Vet Res 2004;65:1185–1188)
Objective—To determine the efficacy of florfenicol
for treatment of calves with naturally occurring infectious
bovine keratoconjunctivitis (IBK).
Design—Randomized controlled field trial.
Animals—63 beef calves and 80 dairy calves
between 4 and 12 months of age.
Procedure—Calves were randomly assigned to 1 of 3
treatment groups. Calves in the SC treatment group
received a single dose of florfenicol (40 mg/kg [18.2
mg/lb] of body weight), SC, on day 0. Calves in the IM
treatment group received florfenicol (20 mg/kg [9.1
mg/lb]), IM, on days 0 and 2. Calves in the control
group received injections of saline solution (0.9%
NaCl), IM, on days 0 and 2. Calves were reevaluated
every other day for 20 days after treatment.
Results—Corneal ulcers healed by day 20 in 48 of 49
(98%) calves treated with florfenicol IM, 39 of 42
(93%) calves treated with florfenicol SC, and 33 of 52
(63%) control calves.
Conclusions and Clinical Relevance—Florfenicol
administered SC (1 dose) or IM (2 doses 48 hours
apart) was effective for treatment of calves with naturally
occurring IBK. ( J Am Vet Med Assoc 2000;216: