Objective—To evaluate equine IgG as a treatment for
kittens with failure of passive transfer of immunity
Animals—13 specific pathogen-free queens and their
Procedure—Kittens were randomized at birth into 9
treatment groups. One group contained colostrumfed
(nursing) kittens; the other groups contained
colostrum-deprived kittens that were administered
supplemental feline or equine IgG PO or SC during
the first 12 hours after birth. Blood samples were collected
at serial time points from birth to 56 days of
age for determination of serum IgG concentrations.
The capacity of equine IgG to opsonize bacteria for
phagocytosis by feline neutrophils was determined
via flow cytometry.
Results—Kittens that received feline or equine IgG
SC had significantly higher serum IgG concentrations
than those of kittens that received the supplements
PO. In kittens that were administered supplemental
IgG SC, serum IgG concentrations were considered
adequate for protection against infection. The half-life
of IgG in kittens treated with equine IgG was shorter
than that in kittens treated with feline IgG. Feline IgG
significantly enhanced the phagocytosis of bacteria
by feline neutrophils, but equine IgG did not.
Conclusions and Clinical Relevance—Serum concentrations
of equine IgG that are considered protective
against infection are easily attained in kittens, but
the failure of these antibodies to promote bacterial
phagocytosis in vitro suggests that equine IgG may
be an inappropriate treatment for FPT in kittens.
(Am J Vet Res 2003;64:969–975)
Objective—To compare castration of dogs by use of intratesticular injection of zinc gluconate with traditional surgical procedures in terms of acceptance by pet owners, ease of use, and short-term outcomes on Isabela Island of the Galápagos Islands.
Animals—161 privately owned male dogs admitted to a neuter program.
Procedures—Medical records of male dogs neutered during a 4-week animal control campaign were reviewed to collect information regarding signalment, method of castration, complication rate, and treatment outcomes.
Results—Of the 161 dogs admitted for castration, 58 were surgically castrated and 103 were treated with zinc gluconate. Dogs were returned to their owners for observation following castration. Wound dehiscence occurred in 2 skin incisions, representing 3.4% of the 58 dogs that underwent bilateral orchiectomy. Necrotizing zinc-gluconate injection-site reactions occurred in 4 dogs receiving injection volumes near the maximum label dose (0.8 to 1.0 mL), representing 3.9% of the zinc-gluconate procedures. Surgical wound complications were treated by superficial wound debridement and resuturing, in contrast to zinc-gluconate injection-site reactions, which all required orchiectomy and extensive surgical debridement, including scrotal ablation in 2 dogs.
Conclusions and Clinical Relevance—Low cost, ease of use, and cultural acceptance of a castration technique that does not require removal of the testes make zinc gluconate a valuable option for large-scale use in dogs, particularly in remote locations lacking sophisticated clinical facilities or skilled surgeons and staff. Further investigation is needed to identify risk factors in dogs for adverse reactions to zinc gluconate and to develop strategies for avoidance.
Objective—To determine the prevalence and severity
of pulmonary arterial lesions in cats seropositive for
heartworms (Dirofilaria immitis) but lacking adult
heartworms in the heart and lungs during necropsy.
Animals—630 adult cats from an animal control shelter
Procedure—Cats were tested for adult heartworms
in the heart and pulmonary arteries and antibody
against heartworms in the serum. Histologic examination
was conducted on the right caudal lung lobe of
24 heartworm- and antibody-positive cats; 24 heartworm-negative and antibody-positive cats; and 24
heartworm-, antibody-, and antigen-negative cats.
Wall areas of 10 small to medium-sized pulmonary
arteries of each cat were measured and expressed as
a proportion of total cross-sectional area.
Results—Heartworm infection or seropositive status
was significantly and strongly associated with severity
of medial hypertrophy of pulmonary arterial walls.
Heartworm- and antibody-positive cats and heartworm-negative and antibody-positive cats had a significant
increase in wall thickness, compared with
wall thickness for heartworm- and antibody-negative
cats. Heartworm- and antibody-positive cats had the
most severe hypertrophy. The proportion with occlusive
medial hypertrophy was significantly higher in
heartworm- and antibody-positive cats (19/24 [79%])
and heartworm-negative and antibody-positive cats
(12/24 [50%]), compared with heartworm- and antibody-negative cats (3/24 [13%]).
Conclusions and Clinical Relevance—Cats with
serologic evidence of exposure to heartworms,
including those without adult heartworms in the lungs
and heart, have a greater prevalence of pulmonary
arterial lesions than heartworm-negative cats without
serologic evidence of exposure. Additional studies are
needed to define the pathogenesis, specificity, and
clinical importance of these lesions. (Am J Vet Res
Objective—To determine whether passive transfer of
IgG in neonatal kittens affects plasma opsonic capacity
and neutrophil phagocytic and oxidative burst
responses to bacteria in vitro.
Animals—22 kittens from 6 specific pathogen-free
Procedure—Kittens were randomized at birth into the
following treatment groups: colostrum-fed,
colostrum-deprived, or colostrum-deprived supplemented
with feline or equine IgG. Blood samples
were collected at intervals from birth to 56 days of
age. Plasma IgG concentrations were determined by
radial immunodiffusion assay. Neutrophil function
was assessed by a flow cytometry assay providing
simultaneous measurement of bacteria-induced
phagocytosis and oxidative burst. The opsonic capacity
of kitten plasma was determined in an
opsonophagocytosis assay with bacteria incubated in
untreated or heat-inactivated plasma.
Results—Among treatment groups, there were no
significant differences in neutrophil phagocytic and
oxidative burst responses to bacteria or opsonic
capacity of plasma. In all samples of plasma, inactivation
of complement and other heat-labile opsonins
significantly reduced the opsonic capacity. Plasma
IgG concentrations in kittens did not correlate with
neutrophil function or plasma opsonic capacity before
or after inactivation of complement.
Conclusions and Clinical Relevance—The plasma
opsonic capacity and neutrophil phagocytic and oxidative
burst responses in vitro of kittens receiving passive
transfer of IgG via colostrum intake or IgG supplementation
and those deprived of colostrum were similar.
The alternate complement pathway or other heat-labile
opsonins may be more important than IgG in bacterial
opsonization and phagocytosis. ( Am J Vet Res
Objective—To determine the pharmacokinetics of
enrofloxacin in neonatal kittens and compare the pharmacokinetics
of enrofloxacin in young and adult cats.
Animals—7 adult cats and 111 kittens (2 to 8 weeks
Procedure—A single dose of 5 mg of enrofloxacin/kg
was administered to adults (IV) and kittens (IV, SC, or
PO). Plasma concentrations of enrofloxacin and its
active metabolite, ciprofloxacin, were determined.
Results—The half-life of enrofloxacin administered IV
in 2-, 6-, and 8-week-old kittens was significantly
shorter and its elimination rate significantly greater
than that detected in adults. The apparent volumes of
distribution were lower at 2 to 4 weeks and greater at
6 to 8 weeks. This resulted in lower peak plasma concentration
(Cmax) at 6 to 8 weeks; however, initial plasma
concentration was within the therapeutic range
after IV administration at all ages. Compared with IV
administration, SC injection of enrofloxacin in 2-weekold
kittens resulted in similar Cmax, half-life, clearance,
and area under the curve values. Enrofloxacin administered
via SC injection was well absorbed in 6- and 8-
week-old kittens, but greater clearance and apparent
volume of distribution resulted in lower plasma concentrations.
Oral administration of enrofloxacin resulted
in poor bioavailability.
Conclusions and Clinical Relevance—In neonatal
kittens, IV and SC administration of enrofloxacin provided
an effective route of administration. Oral administration
of enrofloxacin in kittens did not result in
therapeutic drug concentrations. Doses may need to
be increased to achieve therapeutic drug concentrations
in 6- to 8-week-old kittens. ( Am J Vet Res 2004;65:350–356)
Objective—To characterize the biological effects of
IM administration of a recombinant adeno-associated
virus serotype 2 (rAAV2) vector containing feline
erythropoietin (fEPO) cDNA and determine
whether readministration of the vector or removal
of muscle tissue at the injection sites alters those
Animals—10 healthy 7-week-old specific pathogenfree
Procedure—Cats received 1 × 107 infective units (iU;
n = 3), 1 × 108 iU (3), or 1 × 109 iU (2) of rAAV2-fEPO
vector IM (day 0). Two control cats received an
rAAV2 vector containing the LacZ gene (1 × 109 iU,
IM). In all cats, hematologic variables and serum
fEPO concentration were measured at intervals;
anti-rAAV2 antibody titer was measured on day 227.
In cats that did not respond to treatment, the rAAV2-
fEPO vector was readministered. Injection sites
were subsequently surgically removed.
Results—Compared with control cats, cats treated
with 1 × 109 iU of rAAV2-fEPO vector had increased
Hct and serum fEPO concentrations. One of these
cats developed pure RBC aplasia; its Hct normalized
following injection site excision. Cats receiving lower
doses of vector had no response; on retreatment, 1 of
those cats developed sustained erythrocytosis that
persisted despite injection site removal and the others
did not respond or responded transiently. Antibodies
against rAAV2 were detected in all vector-treated cats.
Conclusions and Clinical Relevance—Gene therapy
may be an effective treatment for cats with hypoproliferative
anemia. However, rAAV2-fEPO vector administration
may result in pure RBC aplasia or pathologic erythrocytosis,
and injection site removal does not consistently
abolish the biological response. (Am J Vet Res 2005;66:450–456)
As community efforts to reduce the overpopulation and euthanasia of unwanted and unowned cats and dogs have increased, many veterinarians have increasingly focused their clinical efforts on the provision of spay-neuter services. Because of the wide range of geographic and demographic needs, a wide variety of spay-neuter programs have been developed to increase delivery of services to targeted populations of animals, including stationary and mobile clinics, MASH-style operations, shelter services, community cat programs, and services provided through private practitioners. In an effort to promote consistent, high-quality care across the broad range of these programs, the Association of Shelter Veterinarians convened a task force of veterinarians to develop veterinary medical care guidelines for spay-neuter programs. These guidelines consist of recommendations for general patient care and clinical procedures, preoperative care, anesthetic management, surgical procedures, postoperative care, and operations management. They were based on current principles of anesthesiology, critical care medicine, infection control, and surgical practice, as determined from published evidence and expert opinion. They represent acceptable practices that are attainable in spay-neuter programs regardless of location, facility, or type of program. The Association of Shelter Veterinarians envisions that these guidelines will be used by the profession to maintain consistent veterinary medical care in all settings where spay-neuter services are provided and to promote these services as a means of reducing sheltering and euthanasia of cats and dogs.
As efforts to reduce the overpopulation and euthanasia of unwanted and unowned dogs and cats have increased, greater attention has been focused on spay-neuter programs throughout the United States. Because of the wide range of geographic and demographic needs, a wide variety of programs have been developed to increase delivery of spay-neuter services to targeted populations of animals, including stationary and mobile clinics, MASH-style operations, shelter services, feral cat programs, and services provided through private practitioners. In an effort to ensure a consistent level of care, the Association of Shelter Veterinarians convened a task force of veterinarians to develop veterinary medical care guidelines for spay-neuter programs. The guidelines consist of recommendations for preoperative care (eg, patient transport and housing, patient selection, client communication, record keeping, and medical considerations), anesthetic management (eg, equipment, monitoring, perioperative considerations, anesthetic protocols, and emergency preparedness), surgical care (eg, operating-area environment; surgical-pack preparation; patient preparation; surgeon preparation; surgical procedures for pediatric, juvenile, and adult patients; and identification of neutered animals), and postoperative care (eg, analgesia, recovery, and release). These guidelines are based on current principles of anesthesiology, critical care medicine, microbiology, and surgical practice, as determined from published evidence and expert opinion. They represent acceptable practices that are attainable in spay-neuter programs.