The Case of an Sry‐Negative XX Male Pug With an Inguinal Gonad

A case of intersexuality in a Pug that was bought as a male in a pet shop is described. The dog was presented at the Veterinary Teaching Hospital, University of Turin, for a reddish mass protruding from the prepuce. The mass had the aspect of an enlarged clitoris, with a caudoventral direction and a dorsal urethral ostium. A gonad was palpable in the left inguinal region. Laparotomy confirmed ultrasound detection of an abdominal uterine structure together with the right gonad. The histology of both gonads was similar, showing an exclusively masculine character, with seminiferous tubules lined only by Sertoli cells; the uterus showed a normal histological structure. Karyological analysis revealed a female karyotype (78,XX), and polymerase chain reaction showed the absence of Sry. The diagnosis was an XX male. The pathogenesis of the XX sex reversal syndrome in dogs is not completely understood, as Sry, the master gene regulating testis differentiation, is not present; to date, no genetic cause has been identified for this phenotypic condition in dogs. This case is unusual because the dog showed an inguinal testis, implying a partial activity of the mechanisms leading to abdominal testis translocation along a gubernaculum and transinguinal migration.     

Cytogenetic and histologic examination of four tortoiseshell cats

Tortoiseshell colored tomcats are very uncommon. In most cases their phenotype is caused by an aberration of sex chromosomes. In this study, we carried out cytogenetic investigations in four tortoiseshell tomacats. In two cases, an XXY syndrome could be proven. Another tortoiseshell tomcat had an XX/XY chromosomal constitution. One tomcat showed an exclusively male XY karyotype. In two cases the testes were histologically examined. In one XXY phenotypically male cat there was no spermatogenesis present. In the tomcat with XX/XY-chimerism spermatogenesis was seen in some testicular tubules.     

Congenital retroflexion of the penis and inguinal cryptorchidism in a presumptive bovine twin with a 60,XY/60,XX/61,XX,+cen chromosome constitution.

Studies were carried out on a yearling Holstein with external genitalia resembling those of a freemartin whose birth and developmental history was unknown. Dissection following slaughter showed testes close to the external inguinal rings, an underdeveloped penis coiled up subcutaneously in the perineum and terminating in a deep fossa at the level of the ischial arch and no evidence of a female genital tract. Chromosome analyses showed 60,XY cells in the blood and 60,XX and 61,XX,+cen cells in other tissues. It is postulated that the animal had a basic 60,XX/61,XX+cen mixoploid chromosome constitution, that the centric fragment functioned as a Y chromosome or as an autosomal modifier of the X chromosome in sex determination which accounted for the animal's Klinefelter syndrome-like abnormalities, and that animal was also twin to a bull which accounted for the presence of 60,XY cells in the blood.     

Infertile mares with chromosome abnormalities

Chromosomal abnormalities have been detected in five mares identified by their poor reproductive performance. All had small gonads and absent or irregular oestrous cycles. One mare was 65, XXX, two were 64, XY sex-reversal females and two were sex chromosome mosaics with karyotypes of 63, XO/64, XX/64, XY and 63, XO/64, XX respectively. This report supports the suggestion made in earlier studies that sex chromosome abnormalities may be a significant cause of sterility in the mare.     

78,XX testicular DSD syndrome in a mongrel dog

Because of an apparent sexual ambiguity (enlarged clitoris), a 1-year-old mongrel dog was presented to the clinic. A positive result on a GnRH stimulation test revealed the existence of functional testicular tissue. A midline laparotomy was performed, and gonads resembling testes were resected along with the adherent parts of the uterine horns. Microscopic examination confirmed that the sampled gonads were testes. Cross-sections of the head and tail of the epididymis revealed their typical structures. All layers of the uterine wall were well-developed. The lumen was stellar, covered by columnar cylindrical epithelium, although locally some epithelial cells had changed in height from columnar to flat. The uterine glands were distributed in functional layer of endometrium in a non-uniform way. Cytogenetic analysis based on the evaluation of metaphase plates of blood lymphocytes showed a female karyotype, 78,XX. PCR amplification of the SRY gene was negative in the studied mongrel dog. This canine disorder may be genetically heterogeneous, potentially with a different mutation in different breeds. An autosomal recessive inheritance for the XX male is suggested in such cases. The present case of sex reversal syndrome concerns a non-purebred dog. In mongrels, it is definitely less likely for the defect to be inherited because of a recessive disorder. According to the recently proposed nomenclature, the described case should be classified as 78,XX testicular DSD syndrome.     

Karyotype evaluation among young horse populations in Poland

Five hundred young horses of the following breeds: Thoroughbred, Silesian, Malopolska, Wielkopolska, Polish Konik, Hutsul, Shetland Pony, Half-bred Anglo-Arabian, Noble Half-bred, Fjord and crosses were cytogenetically investigated. Chromosome preparations obtained after lymphocyte culture were analysed using conventional Giemsa staining and CBG-banding methods. In the case of abnormalities GTG-banding as well as FISH technique were applied. In ten mares different karyotypic abnormalities were diagnosed. One mare showed chromosome chimerism (64,XX/64,XY), eight had sex chromosomal aneuploidy (one in pure line 63,X and seven in mosaic form 63,X/64,XX) and one presented autosomal aneuploidy with mosaicism (64,XX/65,XX,+31). The influence of sex chromosome abnormalities on fertility and the possible utilisation of karyotypic control in any selection programme are discussed.     

Congenital adrenal hyperplasia secondary to 11beta-hydroxylase deficiency in a domestic cat

A calico-colored domestic shorthair cat was examined because of possible cryptorchidism. The cat had a fully formed penis, prepuce, and scrotum, but no descended testes, and exploratory laparotomy revealed a grossly normal female internal genital tract (ie, 2 ovaries, 2 uterine horns, and uterine body). Chromosomal analysis revealed a normal female (38,XX) karyotype. Four months later, the cat was examined because of polyuria, polydipsia, and inappropriate urination. Serum cortisol and aldosterone concentrations were low, and results of an ACTH stimulation test were suggestive of decreased adrenal gland function. Serum ACTH, testosterone, androstenedione, progesterone, 17-hydroxyprogesterone, 11-deoxycortisol, and deoxycorticosterone concentrations were high, and a diagnosis of congenital adrenal hyperplasia secondary to 11beta-hydroxylase deficiency was made. Treatment with prednisone diminished clinical signs but had a variable effect on corticosteroids hormone concentrations. To the author's knowledge, this is the first report of congenital adrenal hyperplasia in a cat.     

Pathological changes of renal tubular dysplasia in Japanese black cattle

Pathological studies were conducted on 91 Japanese Black cattle with a hereditary disease which induced growth retardation, long hooves and renal failure. In calves one to two months old, no gross abnormalities were observed in the kidneys, but microscopical examinations revealed immature epithelia which were arranged irregularly and not attached to the basement membranes in some proximal tubules. In animals three to 36 months old, the kidneys had shrunk perceptibly and had grey-white radial streaks; microscopically they showed severe interstitial fibrosis with round-cell infiltration in the outer zone of the medulla and cortex, and reductions in the numbers of glomeruli and tubules. In the fibrotic areas there were immature epithelia with an irregular arrangement, and the basement membrane of the tubules was thickened. It was concluded that renal tubular dysplasia was the primary lesion of the disease, and that interstitial fibrosis and reductions in the numbers of nephrons were secondary lesions.     

Disorder of sex development (XX male, SRY negative) in a French bulldog

A female French bulldog was presented with an enlarged clitoris. Abdominal surgery revealed a normal uterus and gonads resembling testes. Histologically, the gonads contained seminiferous tubules. The karyotype was XX, and the SRY gene was not detected. A diagnosis of XX male, SRY negative disorder of sexual development was made.     

Naturally occurring lesions of the uterine tube in sheep and serologic evidence of exposure to Chlamydophila abortus.

The uterine tubes from 405 ewes, collected at an abattoir, were assessed grossly and microscopically for abnormalities that correlated with serological evidence of exposure to Chlamydophila abortus. Gross lesions were found in 41 ewes and 86 had microscopic lesions. Enzyme immunoassay (EIA) of serum was used as an indication of exposure of individual ewes to C. abortus; 52 were found to be positive. Chi-squared analysis indicated no association between EIA-positive animals and lesions of the uterine tube.     

Expression of Steroid Hormone Receptors in the Genital Structures of a True Hermaphrodite Pug Dog

Hermaphroditism is a rare and a not well‐understood disordered sexual development (DSD) in dogs. The objective of the study was to analyse the sex steroid hormone receptor (STHR) expression patterns in the internal genital structures, because the responsiveness of the different tissue types to the steroid hormones may have a key role in pathological alterations based on DSDs. Furthermore, the adhesion molecule β‐catenin was investigated by means of immunohistochemistry because of its important role in development, tissue integrity and disease. Molecular sexing was performed via PCR targeting DBX/DBY genes to identify the pug dog as a true XX hermaphrodite. The portions of uterine tissue revealed comparable expression patterns for STHRs as investigated in normal female reproductive tissue. In the male parts, β‐catenin showed strong expression in the Sertoli cells of the seminiferous tubules; this was in contrast to normal testicular tissue. Likewise, the layers of smooth muscle actin‐positive cells surrounding the seminiferous tubules were reduced in the hermaphrodite. The results of this study deepen the knowledge of tissue characteristics in a hermaphrodite dog and highlight the importance of early diagnosis because the STH responsiveness in maldeveloped reproductive tissue might lead to serious problems for the dog.     

Presumptive Sry-negative XX sex reversal in a llama with multiple congenital anomalies.

Multiple congenital abnormalities of the external genitalia consistent with XX sex reversal were detected in a juvenile llama. The llama had a typical female karyotype (74, XX) and did not have a Y chromosome, but a minute chromosome was detected. To determine whether a piece of Y chromosome containing the Sry gene might be located in a small translocation, DNA analysis by polymerase chain reaction was performed; the Sry gene was not detected. Histologic examination revealed ovarian tissue, whereas testicular tissue was not found. External genitalia were partially masculinized, indicating that the urogenital sinus, genital tubercle, and genital swellings had been exposed to androgens during development, although the dam had not received exogenous androgens. Testicular tissue in the ovaries may have been undetected or had regressed prior to birth, as has been reported in sex reversal in mice.     

A survey of malformed aborted bovine fetuses, stillbirths and nonviable neonates for abnormal karyotypes.

Postmortem examinations were performed on 30 morphologically abnormal aborted bovine fetuses, stillbirths and nonviable neonates. Fibroblasts from the pericardium were cultured for chromosome analysis. Karyotypes were successfully completed on 18 animals, of which three were trisomic, one was mosaic monosomic and one was chimeric. All aneuploid calves had multisystemic anomalies. Using chromosomal banding techniques, the abnormal karyotypes were determined to be: 61,XY,+27; 61,XX,+21; 61,XY,+?; 59,XY,-?/60,XY; and 60,XX/60,XY. Bacterial contamination or nonviability of tissues prevented the growth of fibroblasts in culture and cytogenetic analysis of the other 12 animals. It was estimated that 2.0% of all late gestation abortuses and stillbirths may have chromosomal abnormalities characterized by aneuploidy. The findings of this study suggest chromosomal abnormalities characterized by aneuploidy are a significant cause of multisystemic anomalies in aborted bovine fetuses and nonviable neonates.     

SRY negative 64,XX intersex phenotype in an American saddlebred horse

A female American saddlebred horse was presented for surgical correction of a possible pseudohermaphrodite condition. The horse had abnormal external genitalia and exhibited stallion-like behaviour. No evidence of uterine or ovarian tissue was identified on laparoscopic examination, but hypoplastic testicular-like tissue was removed, although this was found to contain no spermatogonia upon histopathological examination. A karyotype was performed and showed the normal chromosomal complement for a female horse (64,XX). Polymerase chain reaction to detect the SRY gene was negative in peripheral blood as well as the testicular-like tissue. This case represents the first report of an SRY negative XX-male sex reversal intersex phenotype, which is a potentially inherited condition, in an American saddlebred horse.     

Endometrial biopsy technique and uterine pathologic findings in llamas

Uterine tissue specimens from 90 llamas with history of infertility were examined and graded microscopically; 83 specimens were obtained by endometrial biopsy and 7 specimens were obtained at necropsy. Fifteen llamas (16.7%) had a normal uterus, which was graded 1A. Twenty-three llamas (25.6%) had minor uterine abnormalities that were graded 1B. Forty-five llamas (50.0%) had appreciable endometritis that was graded 2A. Three llamas (3.3%) had endometritis with gland fibrosis that was graded 2B. Two llamas (2.2%) had notable uterine gland fibrosis that was graded 3A. Two llamas (2.2%) had uterine neoplasia that was graded 3B. Thirty-six llamas had follow-up evaluation; 22 became pregnant, most after some form of treatment. Uterine biopsy in llamas was readily performed without complications and was valuable in identifying a wide range of uterine diseases, most of which were amenable to treatment.     

A hermaphrodite dog with bilateral ovotestes and pyometra

Hermaphroditism was identified in a 3-year-old American Cocker spaniel with an enlarged os clitoridis that was shown as reddish finger-like structure protruding from the vulva. The urethral orifice was located cranially to the base of the os clitoridis. The gonads were situated caudal to the kidneys at the cranial tips of the uterine horns, and were composed mainly of seminiferous tubules and interstitial cells and had ovarian follicles in the cortices. The uterus was enlarged and revealed pyometra. Gross and histopathological findings of the dog suggested hermaphroditism with bilateral ovotestes and pyometra.     

Triploidy (117,XXX) in a stillborn canine pup conceived with frozen semen

Analysis of skin fibroblast cultures from a deformed stillborn female Alaskan Malamute pup revealed a 3n = 117,XXX (normal, 2n = 78,XX) chromosome count. The triploid pup was delivered by cesarean section 5 days after estimated date of parturition, because the bitch failed to start labor. The bitch had been inseminated with thawed frozen semen deposited into the lumen of the uterus approximately 4 days after ovulation. Gross anatomic abnormalities of the pup included omphalocele, diaphragmatic hernia, persistent right aortic arch, atresia ani, and no right forelimb distal to the scapula. The pup also had arthrogryposis of the left carpus, kyphosis of the thoracic vertebrae, widely separated cranial sutures, open fontanelles, hydrocephalus, and cleft palate. Suspected cause of the triploidy was dispermy of an aged oocyte after intrauterine deposition of the thawed frozen semen. Numeric chromosome abnormalities may be causes of fetal deformity or death that can be detected by fetal karyotype.     

First case of sterility associated with sex chromosomal abnormalities in a jenny

Chromosomal abnormalities are one of the main causes of genetic infertility in horses. Currently, their detection rate is rising due to the use of new diagnostic tools employing molecular markers linked to the sex chromosome pair. Despite genetic similarities, there are no previous reports of sterility associated with chromosomal abnormalities in the domestic donkey (Equus asinus). Hereby, we determined the presence of a chromosomal mosaicism in a female donkey with reproductive problems using molecular methodologies developed for horses. A two‐and‐a‐half‐year‐old jenny characterized by morphological abnormalities of the reproductive tract was cytogenetically analysed using conventional and fluorescent techniques and a group of microsatellite markers (short tandem repeat, STR). At the same time, five ultrasound measures of the reproductive tract were taken and compared with eight contemporary jennies of the same breed. After slaughter, morphological examinations showed that the case study had a blind vaginal vestibule defining an empty pouch that covered the entrance of the cervical os. Histopathological studies demonstrated that this abnormal structure was compatible with a remnant hymen. Molecular markers, STR and fluorescent in situ hybridization determinations revealed that the animal was a 62, XX/61,X mosaic and, therefore, the first case of chromosomal abnormalities in the sex pair reported in donkeys.     

Further cases of equine sex chromosome abnormalities

Sex chromosome abnormalities have been detected in a further five mares with clinical histories of small ovaries and absent or irregular oestrous cycles. Three mares had 63,XO karyotypes (X monosomy) and two were sex chromosome mosaics with karyotypes of 63,XO/64,XY and 63,XO/64,XX/64,XY respectively. A sex chromosome abnormality (X monosomy) has also been found in a filly where it was suspected because of her short stature.     

Further cases of equine sex chromosome abnormalities

Sex chromosome abnormalities have been detected in a further five mares with clinical histories of small ovaries and absent or irregular oestrous cycles. Three mares had 63,XO karyotypes (X monosomy) and two were sex chromosome mosaics with karyotypes of 63,XO/64,XY and 63,XO/64,XX/64,XY respectively. A sex chromosome abnormality (X monosomy) has also been found in a filly where it was suspected because of her short stature.