Objectives—To describe the characteristics of
unowned, free-roaming cats and their caretakers who
participated in a trap-neuter-return (TNR) program and
to determine the effect of the program on free-roaming
Sample Population—101 caretakers of 920
unowned, free-roaming cats in 132 colonies in north
Results—Most (85/101; 84%) caretakers were
female. The median age was 45 years (range, 19 to
74 years). Most (89/101; 88%) caretakers owned pets
and of those, most (67/101; 66%) owned cats. The
major reasons for feeding free-roaming cats were
sympathy and love of animals. Most caretakers
reported that the cats they cared for were too wild to
be adopted, but many also reported that they considered
the cats to be like pets. The total surveyed cat
population was 920 before participation in TNR and
678 after TNR. Mean colony size was 7 cats before
TNR and 5.1 cats after TNR. Most cats lived on the
caretaker's property. At the time of the survey, 70%
(644/920) of the cats had been neutered.
Conclusions and Clinical Relevance—The decrease
in the surveyed free-roaming cat population was
attributed to a reduction in births of new kittens,
adoptions, deaths, and disappearances. Recognition
of the human-animal bond that exists between caretakers
and the feral cats they feed may facilitate the
development of effective control programs for feral
cat populations. (J Am Vet Med Assoc 2002;220:
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 determine the effect of vaccination
against FIV on results of serologic assays for FIV
Design—Prospective clinical trial.
Animals—26 specific-pathogen-free cats, 102 laboratory-
reared cats (42 unvaccinated and uninfected, 41
vaccinated and uninfected, and 19 infected with FIV),
and 22 client-owned cats infected with FIV.
Procedure—To determine the onset and duration of
anti-FIV antibody production in cats following vaccination
with a whole-virus vaccine, serum was obtained
from the 26 specific-pathogen-free cats prior to vaccination
and weekly for 10 weeks, then monthly for 52
weeks, after vaccination; serum was tested for anti-FIV
antibodies with lateral flow and microwell plate ELISAs.
To determine the diagnostic performance of serologic
assays for FIV infection, plasma from uninfected, unvaccinated
cats; uninfected, vaccinated cats; and FIV-infected
cats was tested for FIV antibodies with the 2 ELISAs,
a western blot assay, and an immunofluorescence antibody
assay and for FIV antigen with an ELISA.
Results—Anti-FIV antibodies were detected in all 26
vaccinated cats 1 year after vaccination. Sensitivity of
the antibody assays for FIV infection was high (98%
to 100%). Specificity was high in unvaccinated cats
(90% to 100%) but poor in vaccinated cats (0% to
54%). None of the vaccinated or infected cats had
detectable FIV antigen in plasma.
Conclusions and Clinical Relevance—Results suggest
that vaccination against FIV causes false-positive results
for at least 1 year with currently available serologic
assays for FIV infection. Negative FIV antibody assay
results are highly reliable for detection of uninfected
cats, but positive results should be interpreted with caution.
(J Am Vet Med Assoc 2004;225:1558–1561)
Objective—To determine characteristics of free-roaming
cats evaluated in a trap-neuter-return program.
Animals—5,323 free-roaming cats.
Procedure—Data collected included sex, maturity,
pregnancy status, number of fetuses per pregnancy,
cryptorchidism, and occurrence of complications or
Results—Adult cats represented 85% of the population,
and 57% were female. Overall, 19% of adult
females were pregnant, and mean litter size was 3.6
fetuses. Pregnancy rate peaked at 36 to 47% of all
females evaluated in March and April and decreased to
≤ 4% from October through January. Cryptorchidism
was observed in 1.9% of the males; 0.4% of the adult
females had pyometra. Only 1.9% of the cats were
already neutered. Euthanasia and unexpected death
rates were 0.4 and 0.3%, respectively. The most common
severe problems encountered included pyometra,
neoplasia, surgical complications, diaphragmatic hernia,
debilitation, and chronic inflammatory diseases.
Conclusions and Clinical Relevance—Neutering programs
for free-roaming cats should include preparations
to perform more spays than castrations. Typically,
almost half of the female cats trapped during spring
will be pregnant. Cryptorchidism is uncommon but is
encountered on a consistent basis, so care should be
taken to differentiate previous castration from retained
testicles. Euthanasia of debilitated cats for humane
reasons is rarely necessary, and unexpected deaths
occur at a low rate. It is feasible and safe to neuter
large numbers of free-roaming cats in large-scale clinics.
(J Am Vet Med Assoc 2002;221:1136–1138)
Objective—To determine the sensitivity, specificity,
and overall diagnostic accuracy of polymerase chain
reaction (PCR) assays offered by commercial diagnostic
laboratories for diagnosis of FIV infection in
Design—Prospective clinical trial.
Procedure—Blood was collected from cats that were
neither infected with nor vaccinated against FIV, uninfected
cats that were vaccinated with a licensed FIV
vaccine, and cats experimentally and naturally infected
with FIV representing subtypes A, B, and C. Coded
blood samples were submitted to 3 laboratories in the
United States and Canada offering PCR assays for
diagnosis of FIV infection to veterinary practitioners.
All laboratories tested fresh blood samples, and 1 laboratory
also tested samples submitted as dried blood
smears. The FIV infection status in all cats was confirmed
by virus isolation. Sensitivity, specificity, and
correct results were calculated for each PCR assay.
Results—Sensitivity ranged from 41% to 93%.
Specificity ranged from 81% to 100% in unvaccinated
cats and 44% to 95% in cats vaccinated against FIV.
Correct results were obtained in 58% to 90% of 124
cats tested. All tests misidentified both uninfected
and infected cats. False-positive results by all laboratories
were higher in cats vaccinated against FIV than
in unvaccinated cats, suggesting that vaccination
interferes with the performance or interpretation of
PCR assays used for diagnosis of FIV infection.
Conclusions and Clinical Relevance—PCR assays
used for diagnosis of FIV infection presently marketed
to veterinary practitioners in North America vary significantly
in diagnostic accuracy and did not resolve the
diagnostic dilemma resulting from vaccination of cats
against FIV. (J Am Vet Med Assoc 2005;226:1503–1507)
Objective—To evaluate the effect of a long-term trapneuter-return program, with adoption whenever possible,
on the dynamics of a free-roaming cat population.
Design—Observational epidemiologic study.
Animals—155 unowned free-roaming cats.
Procedures—Free-roaming cats residing on a university
campus were trapped, neutered, and returned to
the environment or adopted over an 11-year period.
Results—During the observation period (January
1991 to April 2002), 75% of the cats were feral, and
25% were socialized. Kittens comprised 56% of the
original population. Male cats were slightly more
numerous (55%) than females. At the conclusion of
the observation period, 47% of the cats had been
removed for adoption, 15% remained on site, 15%
had disappeared, 11% were euthanatized, 6% had
died, and 6% had moved to the surrounding wooded
environment. Trapping began in 1991; however, a
complete census of cats was not completed until
1996, at which time 68 cats resided on site. At completion
of the study in 2002, the population had
decreased by 66%, from 68 to 23 cats (of which 22
were feral). No kittens were observed on site after
1995, but additional stray or abandoned cats continued
to become resident. New arrivals were neutered
or adopted before they could reproduce.
Conclusions and Clinical Relevance—A comprehensive
long-term program of neutering followed by
adoption or return to the resident colony can result in
reduction of free-roaming cat populations in urban
areas. (J Am Vet Med Assoc 2003;222:42–46)
OBJECTIVE To characterize the clients served by and the cats and dogs admitted to nonprofit spay-neuter clinics.
DESIGN Cross-sectional survey.
SAMPLE 2,154 dogs and 1,902 cats that were owned by 3,768 survey respondents and admitted to 22 nonprofit spay-neuter clinics across the United States between April 29, 2013, and January 24, 2014.
PROCEDURES Participating clinics distributed surveys to clients during each of 4 quarterly study weeks. The survey collected descriptive information about clients' pets and households as well as their decision-making regarding sterilization of their pets. For each of the study weeks, clinics reported the total number of surgeries, including those involving shelter animals, feral cats, and other owned animals.
RESULTS Respondents indicated that 49% of dogs and 77% of cats had not been examined previously by a veterinarian, except during vaccine clinics. Among animals ≥ 4 months of age, 1,144 of 1,416 (81%) cats and 572 of 1,794 (32%) dogs had not received a rabies vaccination. Previous litters were reported for 204 of 716 (28%) queens and 153 of 904 (17%) bitches. Most clients' (53%) household income was < $30,000 annually. Common reasons for clinic choice included cost; friend, neighbor, or family recommendation; and good reputation.
CONCLUSIONS AND CLINICAL RELEVANCE Nonprofit spay-neuter clinics predominantly served low-income clients and animals lacking regular veterinary care, in addition to animals from shelters and community cats. These clinics increase access to services needed for animal population control and public health.