Endometrial cytology of the normal bitch throughout the reproductive cycle

Samples for endometrial cytology were collected both from live bitches using transcervical uterine cannulation (n=48) and postmortem (n=10). The cells identified were endometrial epithelial cells, leucocytes, erythrocytes, spermatozoa, bacteria and cervical or vaginal cells. The endometrial epithelial cells varied morphologically throughout the reproductive cycle and had signs of degeneration during late dioestrus and during early and mid-anoestrus following dioestrus and postpartum. Neutrophils were the most common leucocytes observed during pro-oestrus, oestrus, dioestrus and early pregnancy, and lymphocytes during anoestrus. Macrophages were frequently seen during anoestrus. Erythrocytes were found in variable numbers at all stages of the reproductive cycle. Spermatozoa were detected in samples collected during oestrus and early pregnancy in bitches which had their last mating one to three days previously. Bacteria were commonly observed during pro-oestrus and oestrus. Cornified cervical or vaginal cells were present during pro-oestrus and oestrus. This study demonstrated that the numbers, types, proportions and morphology of ceils in endometrial cytological samples from normal bitches varied throughout the reproductive cycle.     

Epithelial surface changes and spermatozoa storage in the reproductive tract of the bitch

Spermatozoa are known to bind to the epithelial cells lining the uterine tube in various species, but information in canids is conflicting and sparse. The first aim of this study was to measure the epithelial surface outline (ESO) of different regions of the canine uterine tube in the four stages of the oestrous cycle as an indicator of a changing potential reservoir for spermatozoa. The second aim was to identify the site of sperm storage in the bitch after natural mating. Reproductive tracts were collected from bitches undergoing routine ovariohysterectomy.Histological analysis showed that, when corrected for uterine tube size, the ESO of pro-oestrus (P < 0.005) and oestrus (P < 0.05) tubes were larger than anoestrus, but not metoestrus, tubes. The second study examined reproductive tracts from 12 Beagle bitches at 6, 12, 24 and 48 h after mating. Light and electron microscopy revealed large numbers of spermatozoa in the proximal regions of the uterus and particularly the distal utero-tubal junction (UTJ), with few present in the proximal UTJ or uterine tubes. Spermatozoa were bound by their heads to microvilli on the epithelial surface of the uterine lumen and to ciliated cells in the distal UTJ. This is the first report to measure and document differences in potential epithelial attachment sites of the uterine tubes at different stages of the oestrous cycle and to provide compelling evidence that the main spermatozoal storage site in the reproductive tract of the bitch is the distal UTJ.     

Transport of spermatozoa in the reproductive tract of the bitch: observations through uterine fistula

Using unilateral uterine fistulas, the time required for spermatozoa to reach the end of the fistula after natural mating, artificial insemination (AI) in a normal standing posture (NP), and AI standing on the head (SH) was investigated in each of three stages of estrus. Conceptivity in these bitches was also investigated. Five experimental bitches were tested during a total of 8 estrous periods. The results are as follows; the time required for spermatozoa to reach the end of the fistula was almost the same in the early and middle stages, i.e., 30 sec to 1 min after natural mating and SH and less than 2 min for half the bitches in NP, although no intrauterine transport could be observed in the other half. In most cases of mating during the late stage no spermatozoa were found after any of the 3 methods of insemination. Five animals became pregnant in these experiments, but the other three failed to conceive. The implantation of fertilized ova occurred also in the fistulated uterine horn in all cases of pregnancy.     

Uterine, cervical and vaginal microflora of the normal bitch throughout the reproductive cycle

Samples for microbiological culture were collected from the uterus of bitches using transcervical uterine cannulation (31 samples, 23 bitches) and from the uterus, cervix and vagina post mortem (19 bitches) at all stages of the reproductive cycle. Samples were cultured for aerobic and anaerobic bacteria and for aerobic mycoplasmas. Bacteria were always found in the uterus during prooestrus and oestrus (12 positive in 12 cultures) and rarely at other stages of the reproductive cycle: during anoestrus (one in 14) and other stages (none in 24). When microorganisms were detected at three sites post mortem, those found in the cervix and vagina were always of the same species as those found in the uterus. In six out of 13 instances, microorganisms were found in the cervix or vagina when none were found in the uterus. The mean number of isolates, number of bacteria seen in uterine cytology and bacterial growth were greater (P < 0–005) during oestrus and pro-oestrus than at other stages. Bacteria isolated from the uterus, in order of frequency, were Escherichia coli, Haemophilus species, α-haemo-lytic streptococci, Corynebacterium species, Streptococcus canis, Alcaligenes faecalis, Bac-teroides species, Pasteurella species and Proteus mirabilis. No mycoplasmas were cultured from the samples. This study indicates that the uterus of the normal bitch has a uterine microflora during pro-oestrus and oestrus that is similar to that of the vagina and cervix.     

Immunoglobulins and immunoglobulin-containing cells in the reproductive tract of normal rams

The levels of the immunoglobulins IgA, IgG1, IgG2, and IgM were measured in serum and fluid from various locations in the reproductive tract of normal rams. These fluids included semen, preputial washings, and fluid from the accessory sex glands (ASG), vasa deferens, rete testes, and tissue fluid from the seminal vesicles, bulbourethral glands, epididymal tails and efferent ducts. In addition, the prevalence of specific Ig-containing cells (ICC) was measured in sections of formalin fixed tissues stained by an indirect peroxidase-antiperoxidase labelling technique. Mean IgA levels in semen (1.23 mg/ml) and ASG fluid (0.46 mg/ml), were higher than in serum (0.19 mg/ml) and were at levels higher than IgG1 or IgG2 levels in semen, ASG fluid, and preputial washings, thus confirming the existence of a local immune system primarily in the ASG of ram genitalia. Relatively low concentrations of IgA and IgG in other genital fluids and IgG levels in these fluids were consistent with diffusion from serum. The relatively high prevalence of IgA-containing cells in bulbourethral (56% of all ICC) and prostate (49%) glands confirmed these tissues as major sites of local Ig production. ICC were also found in large numbers beneath pelvic urethral and preputial epithelia, but these were predominantly IgG-containing (88 and 72% respectively).     

Endoscopic examination of the upper respiratory tract and oesophagus in small ruminants: technique and normal appearance

The aim of this study was to describe the technique of rhinolaryngotracheobronchoscopy and oesophagoscopy in small ruminants and to report the normal endoscopic appearance of the structures of the upper respiratory tract and oesophagus. Thirty sheep and 30 goats, all clinically normal, underwent rhinolaryngotracheobronchoscopy and oesophagoscopy using a flexible endoscope (length 100 cm; diameter 4 mm). The anatomical features of the structures and the appearance of the mucosa were investigated. The degree of mucosal pigmentation varied between breeds. The appearance of the pharyngeal tonsil and the shape of the trachea in cross-section showed most individual variation. The technique was easily performed and sedation was necessary in only a few cases. No major complications were encountered. It was concluded that the procedure facilitated more accurate diagnosis and prognosis of conditions of the upper respiratory tract and oesophagus.     

Ultrasonographic appearance of the craniocervical junction in normal brachycephalic dogs and dogs with caudal occipital (Chiari-like) malformation

Ultrasonographic evaluation of the spine, especially of the spinal cord, has been rarely reported in dogs. The atlanto-occipital junction provides a small acoustic window through which examination of the craniocervical transition can be performed. Normal sonographic findings of this region in 10 normal brachycephalic dogs are presented and compared with sonographic findings from 25 Cavalier King Charles Spaniels with the caudal occipital malformation syndrome. Sonographic findings were compared with magnetic resonance imaging findings to determine the extent of cerebellar herniation and syringohydromyelia. Cerebellar displacement into the foramen magnum was clearly identified sonographically; however, syringohydromyelia was not discernable due to bone overlay.     

The effect of phytoestrogens on the reproductive tract

Environmental estrogens may be derived from plants (phytoestrogens), pharmaceuticals or synthetic compounds. They exert estrogenic and/or potentially antiestrogenic effects on farm animals, wildlife and humans. Exposure to these compounds results in some abnormalities in the reproductive tract, changes in the estrous cycle, and possibly protection against the development of hormone-dependent cancer. The data obtained from animal studies suggest that the timing of exposure to phytoestrogens is important, and neonatal exposure causes the most pronounced effects.     

Diagnostic imaging of the reproductive organs of the bitch. Methods and limitations.

This article reviews diagnostic radiology and ultrasonography of the reproductive tract of the bitch. The techniques and limitations of these imaging modalities are described. The applications of these techniques in the bitch for illustrating reproductive disorders are included.     

A contrast radiographic study of the vagina and uterus of the normal bitch

A method is described for investigating radiographically the shape of the bitch's vagina. The intra-pelvic vagina is readily dilated whereas the intra-abdominal vagina is narrow and tortuous, and cranially is typically ‘spoon-shaped’. Contrast medium entered the uterus during pro-oestrus, oestrus and the post-partum period, indicating patency of the cervix at these times. No cervical relaxation was evident at the end of the luteal phase, i.e. during anoestrus. The possible relevance of these findings to the aetiology of pyometra is discussed.     

Echocardiography of the normal bovine heart: technique and ultrasonographic appearance

Fifty-one clinically healthy cows were examined ultrasonographically from the third and fourth intercostal spaces on both sides of the thorax. A 3.0 MHz transducer was used and the heart was examined in the caudal long, caudal short and cranial long axes on the right side, and in the caudal and cranial long axes on the left side. In each position the optimal transducer orientation and the images of the structures were recorded. In the caudal long axis view of the heart on the right (transducer positioned at the fourth intercostal space), all four chambers were visible with the transducer positioned 8 to 10 cm dorsal to the level of the olecranon. The left ventricular outflow tract, consisting of the aortic valve and ascending aorta, were visible in the same position with the transducer rotated 10 to 40 degrees clockwise. In the caudal short axis view of the heart on the right, the left and right ventricles were visible in cross-section with the transducer held at right angles to the ribs in the fourth intercostal space, 3 to 6 cm dorsal to the olecranon and tipped slightly dorsally. In the cranial long axis view of the heart on the right, the right ventricular outflow tract, consisting of the pulmonary valve and pulmonary artery, was visible in the third intercostal space, 8 to 10 cm dorsal to the olecranon with the transducer angled craniodorsally and rotated 10 to 20 degrees clockwise. In the caudal long axis view of the heart on the left, the left and right ventricles and the left ventricular outflow tract were visible with the transducer placed in the fourth intercostal space. In the cranial long axis view on the left, the right ventricular outflow tract was visible.