Journal of Feline Medicine and Surgery (2011) 13, 508–515

doi:10.1016/j.jfms.2011.05.008
CLINICAL REVIEW

FELINE REPRODUCTION
Problems and clinical challenges

Susan Little

Audience Many Ovarian remnant syndrome

veterinarians are closely
involved with pedigree cat Ovarian remnant syndrome (ORS) is the presence of functional ovari-
breeding and have become an tissue with signs of estrus after ovariohysterectomy or ovariectomy.
familiar with the unique Signs of estrus may occur weeks to many years after surgery and
characteristics of feline include lordosis, vocalizing, rolling on the ground and receptivity to
reproduction and breeding intact males.1 The cause of ORS is failure to remove all or part of an
management. However, even ovary at surgery, or revascularization of ovarian tissue inadvertently
veterinarians who do not have involvement with the dropped into the abdomen during ovariohysterectomy/ovariectomy.2,3
pedigree cat fancy require a basic knowledge of Neoplasia in ovarian remnants, such as granulosa cell tumor, is a rare
the reproductive problems that are most likely to be cause of ORS. Age at the time of surgery and the breed of cat do not
encountered in working with non-breeding pet cats appear to influence the risk of ORS, although one report did not find
as well as stray and feral cats. any cases in queens spayed before 4 months of age.1
Clinical challenges This article reviews
reproductive problems and challenges in both Diagnostic methods
sexes – namely, ovarian remnant syndrome, ✜ Diagnosis is most commonly made by observing signs of estrus in
mammary fibroadenomatous hyperplasia, a spayed cat with coincident vaginal cytology (Fig 1) consistent with
congenital anomalies of the reproductive tract estrus (cornified epithelial cells, absence of red/white blood cells,
and pregnancy diagnosis in the queen, and clear background).
cryptorchidism and low libido in the tom.
Evidence base Feline reproduction has not
received the amount of investigation and attention
that has been directed at canine reproduction. FIG 1 Taking a sample for vaginal cytology.
The result is that less data is available both The swabbed sample should be spread across
the slide for examination
for description of normal reproduction and for
management of common problems. This article
reviews most of the available evidence for the
conditions discussed. Efforts should focus on
making information more readily available to the
practitioner and expanding the knowledge base
in this important area of feline medicine.

Whether or not involved

with pedigree cat breeding,
veterinarians require knowledge
of the unique characteristics of
feline reproduction and common Susan Little
DVM DABVP (Feline Practice)
reproductive problems. Bytown Cat Hospital, 422 McArthur Avenue,
Ottawa, Ontario, Canada K1K 1G6
Email: susanlittledvm@gmail.com Clinical Practice

508 JFMS CLINICAL PRACTICE

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© 2011 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.
 R E V I E W / Feline reproductive problems and challenges

The most common location for ovarian remnants are the ovarian pedicles.
Other common sites are the omentum and peritoneal walls.
Remnants may be unilateral or bilateral.

✜ Documentation of serum estradiol levels Mammary fibroadenomatous

>20 pg/ml (>73.4 pmol/l) while signs of hyperplasia
estrus are occurring is also consistent with
ORS, although the diagnosis cannot be ruled Approximately 80% of feline mammary mass-
out if estradiol levels are low. es are neoplastic, most commonly adenocarci-
✜ Another method involves inducing nomas. The remaining 20% are benign and are
ovulation of mature ovarian follicles during predominantly mammary fibroadenomatous
estrus with gonadotropin-releasing hormone hyperplasia (MFH; also called fibroepithelial
(GnRH) (Cystorelin; Merial, 25 µg IM) and hyperplasia). MFH is most commonly seen in
documenting elevated serum progesterone young cycling queens, but may also be seen in
(>2 ng/ml [6.4 mmol/l]) 2 weeks later. pregnant queens, and in male or female cats
✜ Detection of ovarian activity when a treated with progestins (eg, megestrol acetate,
queen is not in estrus has been described by medroxyprogesterone acetate).6,7 Typically
administering the GnRH analogue buserelin most or all of the glands are affected. The
(Receptal; Intervet/Schering-Plough Animal hyperplasia can be severe, leading to tissue
Health, 0.4 µg/kg IM), with measurement of necrosis, ulceration and infection (Fig 2).
serum estradiol 2 h later.4 Serum estradiol
concentrations >3 pg/ml (>11 pmol/l) were Etiology and diagnosis
consistent with the presence of ovarian tissue. MFH is often mistaken for neoplasia on gross
No adverse effects from administration of appearance. Histologically, the lesions consist of
buserelin were noted. benign, unencapsulated, fibroglandular prolif-
Note that care must be exercised when inter- eration. Progesterone receptors have been com-
preting baseline estradiol and progesterone monly found in MFH samples, while estrogen
concentrations, as they are known to exhibit receptors have been found in only 50% of cases.8
considerable fluctuation over time. Also, while The etiology is suspected to be an exaggerated
evaluation of luteinizing hormone (LH) concen- response to natural progesterone or synthetic
trations has been used successfully to determine
if a female cat has been spayed or is intact,5 this
assay has not been evaluated in queens with
ORS and so should be used with caution.

Surgical treatment
Once ORS is confirmed, the ovarian tissue
should be surgically removed. Queens with
ovarian remnants may be at increased risk of
mammary and ovarian neoplasia. Moreover,
many owners will not be tolerant of the estrous
behavior. Exploratory laparotomy is required
to remove the ovarian remnant. A thorough
search of the peritoneal cavity is necessary,
starting at the most common location for
remnants, the ovarian pedicles. Other common
sites for ovarian remnants are the omentum
and the peritoneal walls. Remnants may be
unilateral or bilateral. Surgery is most reward-
ing if performed when the cat is in diestrus or
has been induced to ovulate. The corpora lutea
are visible as yellow–orange structures against
the red background of ovarian tissue. Excised
tissue should be submitted for histopathology
to confirm ovarian tissue has been removed.
In some cases, queens have undergone more
than one laparotomy in an attempt to resolve a b
ORS; failed attempts to locate ovarian rem- FIG 2 (a) Mammary hyperplasia in a young late-gestation pregnant queen. A litter of kittens
nants are a common reason for referral to a was born 12 days later. The queen was treated with cabergoline, broad-spectrum antibiotics
and analgesics. The kittens were hand-raised. (b) The same queen approximately 2 months
board-certified surgeon. later, after ovariohysterectomy. Courtesy of Dr Shelagh Morrison

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R E V I E W / Feline reproductive problems and challenges

progestins, but the disease is also occasionally

reported in sterilized male or female cats with Occasionally, mammary hyperplasia will resolve
no history of progestin therapy. In spayed
queens, ORS may be the initiating cause. spontaneously, but it typically takes several weeks
A diagnosis of MFH is suspected on the to several months to resolve, even with treatment.
basis of clinical signs, patient signalment and
history. Biopsy of affected tissue and
histopathology is confirmatory. However, sur-
gical biopsy of markedly swollen mammary
glands may create incisions that heal poorly
due to wound tension. mg/kg/day SC, days 1, 2 and 7).9,10 One study
monitored 14 queens with MFH for 12 months
Treatment approaches following treatment with aglepristone.11
Treatment varies with the underlying cause. Remission of clinical signs occurred in
Intact queens should be spayed, and a flank an average of 4 weeks. Cats that had been
approach is most appropriate (Fig 3). If the cat treated with long-acting medroxyproges-
is being treated with progestins, treatment terone acetate required treatment for 5 weeks.
should be stopped. The drug of choice for Six of the queens were subsequently bred and
treatment of MFH is the progesterone receptor four delivered normal litters. Aglepristone
blocker aglepristone (Alizin; Virbac, 10–15 may not be available or licensed for cats in
every country.
Anecdotal information suggests other treat-
ment choices include dopamine agonists that
reduce prolactin levels, such as cabergoline
(5 µg/kg/day PO, 5–7 days) or bromocriptine
(0.25 mg/cat/day PO, 5–7 days). Prolactin
appears to be necessary for the maintenance
of the corpora lutea, which produce proges-
terone. For cats that have not received exo-
genous progestins, dopamine agonists may be
useful to reduce endogenous progesterone
levels. In most countries, these drugs are not
licensed in the cat and must be obtained from
a compounding pharmacy. Infections should
be treated with broad-spectrum antibiotics.
Occasionally, MFH will resolve sponta-
neously, but it typically takes several weeks
FIG 3 The flank approach to ovariohysterectomy is useful
to several months to resolve, even with
in cases of mammary hyperplasia treatment.

Spayed or intact?
It may be difficult to determine if an adult queen with unknown shows a positive result when serum LH level is >1 ng/ml
history has been previously spayed. Traditional methods to (Witness-LH; Synbiotics Corporation). The test was developed
determine reproductive status include observing for signs of for timing of canine ovulation and has been validated in the
estrus and examining the ventral abdomen (or flank) for a queen – test sensitivity and specificity for determination of
surgical scar that may be due to reproductive status were determined to be
ovariohysterectomy/ovariectomy. Surgical Surgical scars will not be 100% and 92%, respectively.5 A single
scars will not be evident on all cats – and, negative test is highly likely to indicate a
if a scar is found, there is no guarantee it evident on all cats sexually intact queen. A single positive test
is from surgical sterilization. suggests a spayed queen, although
– and, if a scar is found,
Serum LH can be used to determine false-positives may occur if an episodic
reproductive status. LH is released from there is no guarantee it is LH surge is sampled or the queen is in
the anterior pituitary gland in response to estrus. The manufacturer recommends
copulation. LH stimulates ovulation and from surgical sterilization. that positive tests be confirmed with
luteinisation of mature ovarian follicles. In a second sample taken 2 h later.
intact queens, serum LH is maintained at basal levels through Anecdotally, equivocal test results have been reported in some
the negative feedback provided by ovarian estradiol secretion. spayed cats. Some commercial laboratories offer LH testing to
Following ovariohysterectomy/ovariectomy, this negative feed- veterinarians, but these assays may not have been validated
back is lost and serum LH levels elevate persistently. for the dog or cat, so investigation to determine validity
A rapid, semi-quantitative colorimetric assay is available that is recommended.

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Pregnancy diagnosis
Clinical signs
Failure of a queen to come back into heat after breeding is one of
the most obvious signs of pregnancy, but pseudopregnancy will
produce the same effect. However, queens experiencing a pseudo-
pregnancy will usually return to heat within 50–60 days of the last
estrus. One of the first physical indications of pregnancy is ‘pinking’
A pregnant
of the nipples, which occurs around days 15–18 after ovulation. This queen at term.
change in the nipples, which become noticeably pinker and easier Radiography
is useful for
to see as they increase in size and the hair around them recedes determining
somewhat, is most obvious in maiden queens. It can be recognised the number of
fetuses, simply
with experience in queens that have had several litters as well. by counting
the number of
Palpation skulls present

The developing fetuses can be palpated in the abdomen as early as

14–15 days after breeding, but most easily at about 21–25 days. They Ultrasonography
remain distinctly palpable up to about 35 days, at which point the Ultrasound is a more sensitive test for pregnancy than radiography.
fetuses and placentas are sufficiently large that they cannot easily be The gestational sac, a spherical anechoic structure slightly com-
distinguished individually. Towards the end of pregnancy, the heads pressed at the pole, can be detected at 11–14 days, and the embryo
of fetuses may be very easy to palpate. at 15–17 days post-breeding.14 From day 30, it is possible to identify
fetal organs. Details on the time of ultrasound appearance of
Hormonal assay various fetal and extra-fetal structures in the cat have been pub-
Traditionally, there has been no blood test available in the cat to lished.15,16 A benefit of ultrasound is the ability to determine fetal
detect pregnancy. Cats do not produce a placental hormone simi- viability through detection of a beating heart (about 16 days) and
lar to human chorionic gonadotropin (hCG), which is the basis for fetal movement (about 32 days). Fetal heart rate in the cat averages
some human pregnancy tests. However, the hormone relaxin is about 230 beats per min (range 193–263 beats per min) and remains
produced primarily by the placenta and is, therefore, a useful constant throughout gestation, unlike the dog.17 Gender determina-
marker for pregnancy. Relaxin levels increase in pregnancy but tion is even possible, at about days 38–43 post-breeding.18
not in pseudopregnancy. An in-clinic test kit (Witness Relaxin; Early fetal death is also identifiable – ultrasound exams performed
Synbiotics) has been developed as a rapid means of pregnancy on consecutive days will show that the gestational sacs decrease in
detection in cats and dogs. The test requires a small volume of size. However, ultrasound may not be as good as radiography for
plasma and results are available in about 10 mins. determining the number of fetuses present. The ultrasound exam
In a study designed to evaluate the commercially available relax- views each fetus individually and movement of the queen or the
in test kit, 11 queens were mated and monitored for pregnancy.12 uterus makes identification of individual fetuses confusing.
All queens were confirmed pregnant and delivered kittens. An addi- Ultrasound pregnancy diagnosis is 99% accurate at 28 days.
tional 13 pregnant queens undergoing ovariohysterectomy were
also tested. A group of 23 non-pregnant cats were tested as con-
trols. The kit was able to detect pregnancy between days 20–25 of Gestational age and due date
gestation. All pregnant queens tested negative within 5 days post- Prediction of gestational age (GA) and date of parturition is
partum. In the control group, two cats tested false-positive, both possible using fetal ultrasound measurements of head (HD)
of which had large ovarian cysts. This suggests another possible or body diameter (BD).19
source of relaxin production in some queens. The test was estimat-
ed to have 100% sensitivity and 91% specificity in cats after day 25 GA (days) = 25 x HD + 3 or 11 x BD + 21
of gestation, with a positive predictive value of 93%.
Days before parturition = 61 – GA
Radiography
Radiography may be used to detect pregnancy once fetal bones Using these formulae, the due date can be estimated ± 2 days
begin to mineralize, as early as 25–29 days before parturition.13 about 75% of the time. Ideally, the measurements should be
Until this time, only uterine enlargement may be detected. It is not taken 23–28 days post-breeding.
possible to distinguish pregnancy from uterine disease (eg, pyome-
tra) at this point. There is a predictable sequence of radiographic Many sonographers prefer that the hair coat is clipped as this
bone mineralization in the cat, similar to that of the dog, but begin- gives the best image quality. If the hair coat is not going to be
ning about 1 week earlier in gestation.13 In one study, prediction of clipped, alcohol or another wetting agent can be used in addition
date of parturition within 3 days was possible for 75% of 32 cats to acoustic coupling gel to decrease the amount of air between
(and within 7 days in all cats) using references for bone mineraliza- the transducer and the skin, and thereby improve image quality.
tion.13 Not all structures were reliable for prediction of parturition, However, it is still possible to get a false-negative pregnancy diag-
however. Mineralization of the humerus and femur occurs over the nosis early in pregnancy if the hair coat is not clipped. Ideally, the
narrowest range, while the ulna, fibula and pelvic bones have more queen should have a full bladder to move the bowel out of the way
variable mineralization times. The fibula, calcaneus and phalanges and also to move the uterine body out of the pelvic canal so it is
may not become visibly mineralized before parturition. Another use more readily imaged. It also helps to fast the queen for 12 h before
of radiography is in determining the number of fetuses, simply by the ultrasound examination so that intestinal gas is less likely to
counting the number of skulls present. obscure the views, especially in early pregnancy.

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Congenital anomalies in the

reproductive tract of the queen

Congenital anomalies of the queen’s reproduc-

tive tract are not common and are poorly
described in the literature. Segmental aplasia/
hypoplasia/agenesis of the uterine horn, often
called uterus unicornis, may be encountered
occasionally and can present difficulties for
veterinarians when found incidentally during
ovariohysterectomy/ovariectomy (Fig 4). FIG 4 (a) Uterus unicornis
discovered in a young queen
Anecdotally, this condition appears to be more at ovariohysterectomy.
common in Ragdoll cats than in other breeds (b) Although one uterine
horn may be hypoplastic or
or non-pedigree cats. One uterine horn may be missing, the ipsilateral ovary
missing or reduced to a thread-like remnant, a
is almost always present.
Courtesy of Dr Jim Sweetman
and the ipsilateral kidney is often absent.20–24
However, both ovaries are typically present
and the surgeon must ensure the ipsilateral Failure to
ovary is found and removed during neutering
surgery. Failure to remove the ipsilateral ovary remove the
is likely to result in ORS and necessitate an
exploratory laparotomy at a later date.
ipsilateral
When one normal uterine horn and ovary ovary is likely
are present, the queen may have normal
estrous cycles and may become pregnant. to result in
However, segmental aplasia may cause failure
to conceive associated with fluid accumula-
ovarian
tion in the uterine lumen, depending on the remnant
location of lumen occlusion.20,25
Ultrasonography may be a useful tool for syndrome.
diagnosis of uterine abnormalities in some b
infertile queens.

Cryptorchidism
Cryptorchid configuration
The testes are normally descended into the Most cryptorchids are unilateral (78–90%),
scrotum by birth or shortly afterwards. The with left and right sides equally affected. In
testes may move freely up and down in the one study where the location of the retained
inguinal canal prior to puberty, however. testis was recorded, 49% were inguinal,
Cryptorchidism is failure of one or both 33% were abdominal and 14% were with-
testes to descend into the scrotum and in the inguinal ring.26 In the author’s
remain there by 7–8 months of age. It is practice, 87% of 72 cats had unilateral
uncertain if cryptorchidism is linked to cryptorchidism and the most
Terminology
other congenital defects in cats. Cryptorchidism is the most common congenital
common configuration was the uni-
The prevalence of cryptorchidism in defect of the feline urogenital system. The term lateral inguinal cryptorchid (51.6%
cats has been reported as 1.3–3.8%, ‘monorchid’ refers to total absence of one testis. of cases). Bilateral cryptorchids are
which is generally lower than the Monorchidism is very uncommon in cats. likely to have abdominally retained
prevalence in dogs.26–28 In one study Unilateral testicular agenesis has been report-
ed, with the finding of a rudimentary spermat-
testes. If one testis is in the scrotum, it
of over 100,000 feral cats admitted to ic cord and no associated testis. 26 may be difficult to determine if it is on
trap–neuter–return programs, 1.3% of The term ‘anorchid’ refers to the total the left or right side. Pushing the scro-
male cats were cryptorchid.29 In another absence of both testes, and is an tal testis dorsally and cranially toward
study of over 5000 free-roaming cats admitted exceedingly rare event. the inguinal canal can help determine its
to a trap–neuter–return program, 1.9% of the
males were cryptorchid.30 In the author’s prac-
tice, records of 4140 cats presented for castration
over a 10-year period were reviewed. Seventy- In the author’s practice, 72 of 4140 cats (1.7%)
two cats (1.7%) were identified as cryptorchid.
presented for castration over a 10-year period
Of the cats presented for castration, 10.5% were
of a pedigree breed, with a total of 22 breeds were cryptorchid. Of these, the most common
represented. Among the pedigree cats, 6.2%
were identified as cryptorchid. The highest configuration was the unilateral inguinal
incidence was in the Ragdoll breed (>18%). cryptorchid (51.6%).

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Abdominally retained testes have been examined histologically and

typically no sperm are found. Cats with retained testes located
outside the abdomen may, however, be fertile.

location.31 It may be difficult to palpate an There is no treatment proven to cause a

inguinal testis if the cat has large inguinal fat retained testis to descend into the scrotum.
pads, unless the testis is located caudal to the Attempting treatment in an animal intend-
fat pad. The inguinal lymph node and fat pad ed for breeding is considered unethical.
are commonly confused with inguinal testes Treatment with gonadotropins has not been
on palpation. successful. In other species, surgical
Abdominally retained testes have been removal of the retained testis is routinely
examined histologically and typically no recommended because the retained testis is
sperm are found. The higher temperature at risk of neoplasia or torsion. Torsion of the
inside the body suppresses development of spermatic cord has not been documented in
sperm. Cats with retained testes located out- the cat and testicular tumors are very rare.
side the abdomen, however, may be fertile. Cryptorchid cats that have only the
These testes produce testosterone so that scrotal testis removed will, however,
affected cats have the typical male pheno- display all the normal behaviors of
type (thick skin on neck/shoulders, an intact male. Case studies on
Protocols for provocative
broad face) and behaviors (libido, cryptorchid cats mostly report
testosterone testing
aggression, urine marking, etc). ✜ Obtain baseline serum testosterone sample; unsuccessful attempts to locate the
administer 25 µg GnRH IM (Cystorelin; Merial); undescended testis; owners sub-
Confirmation of cryptorchidism obtain second sample for testosterone sequently seek veterinary care
In one study, only 22% of cat owners concentration 1 h later because of odoriferous urine and
Obtain baseline serum testosterone
were aware their pet was cryptorchid.28 ✜sample; administer 250 IU hCG IM;
unwanted behaviors (eg, urine
All male cats should be examined for obtain second sample for testosterone spraying, aggression, seeking
cryptorchidism during wellness visits. If a concentration 4 h later32 females). Therefore, it is important that
retained testis is suspected, there are two both testes are removed to avoid unwant-
ways to confirm the condition. The simplest is ed behaviors that may provoke abandon-
to check for testosterone-dependent penile ment or relinquishment to a shelter.
spines (Fig 5). Penile spines will atrophy by 6
weeks following complete castration. Cryptorchidectomy
Gonadotropin stimulation testing has also Testes that are palpable in the inguinal
been used to detect retained testes. subcutaneous tissue can be removed via a
Testosterone levels fluctuate in the cat, so rest-
ing samples are not very informative and
provocative testing must be used. Various All male cats should be examined for
protocols have been described, two examples
of which are shown above right. Resting
cryptorchidism during wellness visits.
testosterone levels in intact male cats are If a retained testis is suspected, the simplest way
<3.0 ng/ml. Provocative testing will induce a
marked elevation of serum testosterone in the to confirm the condition is to check for
intact male. testosterone-dependent penile spines.
The mode of inheritance is suggested to be
recessive and polygenic, and cryptorchid
males should not be used for breeding.26
Cryptorchidism is an example of a sex-limited
trait: the trait is physically expressed only in
the male even though it can be carried by
females. Both the sire and dam of an affected
cat should be considered to be carriers. Some
full siblings of an affected cat will also be
carriers. A reduction in the number of cryp-
torchid cats in a breeding program can be
achieved by removing affected males and car-
rier parents from breeding. If the problem is
widespread in a family line, full siblings of an a b
affected cat should also be eliminated from FIG 5 Glans of the penis of (a) an intact tom cat with penile spines and (b) a castrated cat
the breeding program. without penile spines

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Poor libido
Poor libido in the breeding tom cat is a common complaint and It is preferable to bring the queen to the tom, as many toms will
may be associated with a variety of factors. Successful breeding not breed successfully when outside their own territory. In pedi-
tom cats must be physically, socially and sexually mature. Ideally, gree catteries, tom cats may be housed separately in cages or
a young inexperienced tom should be paired with a calm, mature enclosures because of urine marking behavior and to control
and experienced queen. In some late-maturing breeds, libido reproduction. Tom cats often dislike changes to their territory,
cannot be assessed properly until 2–3 years of age. even changes in odor such as when scented cleaners are used.
Poor libido is often caused by management problems or The enclosure for a breeding tom cat must provide enough
underlying medical conditions. Investigation requires a thorough space to allow for normal exercise. Cats value vertical space, so
physical examination, a medical history and collection of a provision of areas to climb, or shelving, is very important. It also
minimum database (complete blood count, serum chemistry, provides a way for the tom to retreat from the post-coital reac-
urinalysis and feline leukemia virus and feline tion of the queen to avoid being swatted.
immunodeficiency virus testing). Non- The tom cat’s Inadequate housing may inhibit the breeding
reproductive disease, such as dental disease behavior of normal tom cats.
or degenerative joint disease, may influence environment is very Measurement of baseline testosterone in
willingness or ability to mate. Chronic illness, tom cats with poor libido is not informative;
important . . .
such as upper respiratory tract infection or provocative testing must be used (see
diarrhea, may lead to poor body condition and Inadequate housing discussion on diagnosis of cryptorchidism).
diminished libido. Administration of supplemental testosterone
Information should also be obtained on the may inhibit the in an attempt to correct poor libido is inappro-
cat’s housing, diet (including nutritional sup- breeding behaviour priate. Exogenous testosterone may suppress
plements) and medications (both prescription release of GnRH and LH, thereby interrupting
and non-prescription). The tom cat’s environ- of normal tom cats. testosterone synthesis by the interstitial cells
ment is very important for breeding success. of the testes.

It is not appropriate simply to ligate the damage to the ureters.26 Abdominal testes are
often located near the bladder (Fig 6), but can
vas deferens and testicular vessels in the hope be present in the internal inguinal ring or in
the inguinal canal. The best procedure is to
a retained testis will atrophy. The blood supply can find the vas deferens and follow it caudally to
re-establish and the testis remain functional. the testis. Applying gentle traction to the vas
deferens may facilitate location of the testis by
detecting its movement. While it can be frus-
trating trying to locate the retained testis in
simple incision. In other cases, a caudal mid- some cases, it is not appropriate simply to
line incision and dissection deep to the ligate the vas deferens and testicular vessels in
inguinal fat pad is required. The external the hope the testis will atrophy. It is possible
inguinal ring should be examined but care for the blood supply to re-establish and the
should be taken not to damage structures in testis to remain functional.
the femoral triangle. For abdominally retained
testes, laparotomy via a midline approach
is required, although laparoscopic-assisted
cryptorchidectomy has also been
described.33–35 Advantages of a laparoscopic
technique over laparotomy include minimal
invasiveness, reduced tissue trauma and,
potentially, reduced postoperative pain and
fewer complications. The principal disadvan-
tage is the need for specialized equipment,
with the associated costs and expertise
required. Initially, the laparoscopic approach
may take longer to perform than a traditional
laparotomy until the practitioner gains experi-
ence with the technique.
Surgical techniques for removal of abdomi-
nal testes have been described elsewhere.31 FIG 6 The retained testis
Use of a spay hook to retrieve the vas deferens in cats with abdominal
cryptorchidism is often found
is not recommended because of the risk of near the bladder

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[abstract]. J Vet Intern Med 2003; 17; 432. urogenital abnormalities in a Persian cat. J Feline
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