Topic:Uterine Health
Uterine health in horses pertains to the condition and functionality of the uterus, an essential component of the mare's reproductive system. The uterus is responsible for supporting the development of the embryo and fetus during gestation. Various factors, such as infections, inflammation, and anatomical abnormalities, can impact uterine health, potentially affecting fertility and reproductive performance. Common conditions affecting the equine uterus include endometritis, pyometra, and uterine cysts. Assessment of uterine health often involves diagnostic tools like ultrasonography, endometrial biopsies, and cytological evaluations. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, pathology, diagnostic techniques, and treatment options related to uterine health in horses.
Dynamics of the acute uterine response to infection, endotoxin infusion and physical manipulation of the reproductive tract in the mare. The uterine responses after the infusion of saline (PBS), a bacterial suspension, or lipopolysaccharide derived from Escherichia coli, and after stimulation of the reproductive tract were compared. All infusions provoked a response involving both serum proteins and leucocytes. Protein levels peaked within a few hours of infusion, whereas leucocyte concentration peaked later at around 6 h. Bacterial recovery from the uterus followed a similar pattern, with recovery falling dramatically by 12 h. In mares known to be susceptible to infection large numbers of bacteria were again recovered after 24...
[Endometrial cysts in the mare. 1. Post-mortem studies: occurrence and morphology]. During macroscopic post-mortem examinations of the genital tract in 104 mares endometrial cysts occurred in 14 (13%) cases. Whereas in mares up to the age of 10 years cystic changes were absent, endometrial cysts occurred in 19% of the animals above the age of 10 years. In 6 mares only 1-2 cysts per uterus were found, and in 8 animals there were between 5 and 18 cystic changes per organ. The cysts were equally distributed in the uterus body and horns. Sporadically occurring cysts were about 11 mm in diameter with a decreasing size to a mean value of 5 mm in multiple cysts. Predominantly in the...
Role of anaerobic bacteria in equine endometritis. This study, performed over 3 breeding seasons, surveyed anaerobic and aerobic bacterial isolates from 362 clitoral and endometrial swabs and uterine washes from 263 Thoroughbred maiden, foaling, foal heat and barren mares, and from 113 urethral, urethral fossa, preputial and pre-ejaculatory fluid swabs from 29 Thoroughbred stallions. The significance of isolates was determined by their association with acute endometritis, as determined by concurrent endometrial smear results and by consideration of age and reproductive status before and after the survey. The results suggest that the horse uter...
Factors affecting uterine clearance of inoculated materials in mares. Twelve acyclic mares of various ages (2-29 years) and parity (maiden-multiparous) were given oestradiol-17 beta i.m. (winter 1982) or progesterone i.m. (winter 1983) to induce changes in the endometrium consistent with oestrus and dioestrus, respectively. After hormone treatment, mares were inoculated intrauterine with 50 ml saline containing 5 X 10(5) Streptococcus zooepidemicus bacteria, 51Cr-labelled 15-micron microspheres, and 500 mg charcoal (Groups E + B and P + B) or microspheres and charcoal only (Groups EC and PC). At 5 h after inoculation uteri were flushed with 50 ml saline containi...
Effect of uterine inflammation and ultrasonically-detected uterine pathology on fertility in the mare. The incidence of intrauterine fluid collections during dioestrus (12/43, 28%) and uterine cysts throughout the oestrous cycle (11/73, 15%) found in this study indicates that these ultrasonically detectable abnormalities are prevalent in mares. The hypothesis that uterine cysts do not affect pregnancy was not supported. Intrauterine fluid collections at dioestrus represented the presence of an inflammatory process as indicated by a high biopsy score, reduced progesterone concentrations, and a shorter interovulatory interval. Mares with fluid collections at dioestrus had a lower pregnancy rate a...
Comparison of progesterone and progesterone + oestrogen on total and specific uterine proteins in pony mares. Eight ovariectomized pony mares were used to test the effect of various doses of progesterone (0, 50, 150, 450 mg/day, in oil, i.m., for 10 days) on progesterone and LH in the peripheral circulation, and on total protein and uteroferrin in uterine secretions. Progesterone increased uteroferrin, but there were no differences amongst doses of progesterone. Progesterone treatment decreased LH, and tended to increase total protein. Eighteen ovariectomized mares were given vehicle, oestradiol (10 mg/day, in oil, i.m.), progesterone or progesterone + oestradiol for 28 days. Both the last two steroid...
Hormonal changes associated with induced late abortions in the mare. Two mares received PGF-2 alpha twice daily until abortion and 2 mares received a combined treatment with oestradiol benzoate and oxytocin. The mares were about 150 days pregnant. The PG-treated animals aborted after 37 and 61 h, respectively, and the fetuses were expelled in intact fetal membranes. The other 2 mares aborted 13 and 27 h after the first oxytocin injection, respectively, and showed strong uterine contractions and expelled the fetuses in disrupted fetal membranes. Concentrations of 15-ketodihydro-PGF-2 alpha increased both after PG and oxytocin injections and in association with t...
Concentrations of uterine luminal prostaglandins in mares with acute and persistent endometritis. Intrauterine infusion of 1 per cent oyster glycogen solution was used to induce acute endometritis in four genitally normal mares. Numbers of viable neutrophils recovered in uterine washings had increased by 1 h after infusion and remained elevated for at least 72 h. There was a significant correlation between numbers of viable neutrophils and total protein concentrations and between prostaglandin (PG)F and PGE2 concentrations in washings. There was also a significant relationship between concentrations of 15-keto-13, 14-dihydro PGF2 alpha in plasma and PGF in washings. Intrauterine concentrat...
The functional competence of uterine-derived polymorphonuclear neutrophils (PMN) from mares resistant and susceptible to chronic uterine infection: a sequential migration analysis. The functional competence of uterine-derived polymorphonuclear neutrophils (PMNs) from 28 mares was measured for migration responsiveness by use of a chamber (filter) assay. Uterine infection was induced with Streptococcus zooepidemicus in mares considered resistant to chronic uterine infection (Grade I). In sequential analysis of uterine flushings obtained from these mares 5, 12, 15, 20, and 25 h after infection was induced, PMNs showed an initial rise at 12 h (from 5), then a general decline in migration response and in concentration of cells per ml from 12 through 25 h post-inoculation. In ...
Recovery and evaluation of embryos from normal and infertile mares. To evaluate embryo transfer as a possible method to circumvent infertility in mares, embryos from 14 normal and 14 infertile mares were collected three times and examined. Fewer flushes (p less than 0.05) from normal than infertile mares (1/42 vs 9/42) contained only abnormal embryos whereas more flushes (p less than 0.05) from normal than infertile mares contained one or more normal embryos (28/42 vs 8/42). More flushes (p less than 0.05) from normal than infertile mares contained embryos (29/42 vs 17/42). The embryo diameters (mm) at either day-7 or day-8 post ovulation were greater (p less ...
Diseases of the abdomen. Because the abdomen of the adult horse is too thick to obtain good-quality radiographs, diagnostic ultrasound is a particularly valuable imaging modality in the diagnosis of abdominal disease. The size, shape, position, and texture of the liver, spleen, kidneys, urinary bladder, gravid uterus, and gut wall can be determined by scanning the abdominal surface. The presence or absence of abdominal fluid can be determined efficiently. Gut motility as well as ileus secondary to peritonitis or obstruction can be assessed. Suspected adhesions of the bowel can often be documented, and primary or secon...
Morphologic evaluation of acute endometritis in mares with differing resistance to uterine infections. The study was designed to determine differences between normal mares and mares with endometrial pathology in the inflammatory response after bacterial challenge. Six normal mares (biopsy category I) and 4 mares with pathological endometrial changes (biopsy category II) were given an intrauterine infusion of β-hemolytic streptococci on the second day of estrus. All mares had a similar kind of inflammatory response after the bacterial inoculation as assessed by rectal and vaginal examinations. There were no significant differences in the amount of discharge, uterine tone, uterine size and cervi...
Specific antibody in the equine genital tract following local immunisation and challenge infection with contagious equine metritis organism (Taylorella equigenitalis). Antibody in serum, uterine and vaginal secretions was measured following local immunisation and experimental infection with the organism of contagious equine metritis (Taylorella equigenitalis). Intrauterine immunisation with killed T equigenitalis stimulated a systemic IgG titre and a uterine IgA and IgM response. Subsequent challenge with the organism, however, resulted in a characteristic metritis in both control and vaccinated mares. Antibody in serum and secretions was increased following challenge infection, dwarfing the response to immunisation. The local response was restricted to the ...
Opsonization of bacteria by uterine secretions of cyclic mares. Uterine flushings collected from mares before and after bacterial-induced inflammation were assayed for ability to opsonize Streptococcus zooepidemicus for phagocytosis by polymorphonuclear leukocytes. Opsonization was measured as the peak phagocytic rate of bacteria preincubated with uterine flushings relative to the peak phagocytic rate of unopsonized bacteria. Flushings from four mares with noninfected uteri were unable to opsonize bacteria regardless of whether uteri were flushed at estrus or on day 10 postovulation. In a second experiment, 7 X 10(9) live S. zooepidemicus were inoculated i...
Effects of 6-MBOA on reproductive function in ponies, mice, rats and mink. The effect on reproduction of the plant derivative 6-methoxybenzoxazolinone (6-MBOA), which stimulates reproductive function in voles, was tested in pony mares, laboratory mice and rats, and mink. There was not a significant effect of intravenous injections of 6-MBOA on the ovarian follicles during the transition between the anovulatory and ovulatory seasons in mares. No significant effect of intraperitoneal injections of 6-MBOA on the weight of uterus or ovaries was found in eight-week-old mice, failing to confirm the results of an earlier report. In immature white rats, 6-MBOA treatment resu...
Effect of cycle stage on immunoglobulin concentrations in reproductive tract secretions of the mare. The effect of cycle stage on immunoglobulin and albumin levels in serum, follicular fluid, oviductal, uterine and vaginal secretions was measured. There was no variation in serum immunoglobulin levels during the oestrous cycle, although IgM levels were elevated in cyclic mares compared to non-cyclic (immature and anoestrous) animals. Similarly, there was no cyclical variation in follicular or oviductal protein concentrations. In the uterus, IgG and IgA levels relative to total protein were higher in oestrogenic than in progestagenic secretions, while the trend in relative IgM concentrations wa...
Uterine involution in mares treated with progesterone and estradiol-17 beta. Bacteriology, histology, and scanning electron microscopy were used to evaluate uterine involution in 27 mares treated with daily injections of 150 mg of progesterone and 10 mg of estradiol-17 beta, commencing within 18 hours of parturition. These findings were compared with those for 24 untreated mares at postpartum day 10 or 11. The treatment resulted in significantly (P less than 0.05) greater uterine gland proliferation. Gland density was significantly (P less than 0.05) greater in mares treated for 6 to 10 days than in those treated 2 to 5 days. The proportion of ciliated cells to secreto...
Quantitation of the immunoglobulins in reproductive tract secretions of the mare. IgG, IgA, IgM and albumin concentrations were measured in serum, follicular fluid and oviductal, uterine and intestinal secretions of the horse. Follicular protein concentrations were found to be dependent on serum concentration and molecular size. Of the immunoglobulins only IgG was detectable in oviductal secretions, but IgG:albumin ratios did not differ significantly from those in serum. IgG, IgA and IgM were measured in uterine secretions, with IgG predominant. Serum transudation into uterine secretions was minimal. In intestinal secretions, IgA levels were slightly higher than IgG, with a...
Endometritis in the mare caused by a Coryneform organism–a case report and experimental studies. Persistent purulent endometritis in a mare was attributed to an unclassified species of Corynebacterium. Following intrauterine infusions of 20% betadine for 5 days the purulent vulval discharge ceased and the mare appeared clinically normal. Based on histological examination of endometrial biopsy samples, the severe acute inflammatory reaction had largely resolved 2 days after therapy. Three maiden mares considered resistant to bacterial endometritis received single intrauterine inoculations of 1.8 X 10(9) colony-forming units of the Corynebacterium species. The uterine response was followed ...
Antibacterial activity of mare uterine fluid. Luminal fluid from the mare uterus was used to investigate its relation to antibacterial defenses. Uterine flushings were collected at Day 3 of estrus, Day 8 postovulation and Day 15 postovulation. Uterine proteins were concentrated by ultrafiltration, dialyzed and examined for chemotactic activity to neutrophils and for antibacterial properties. Serum taken at the time of flushing was dialyzed and studied in a similar manner. Neutrophil migration in response to serum from Day 3 estrus and Day 8 postovulation was increased (P less than 0.05) above controls. Uterine protein from Day 8 postovula...
Chemotactic properties and protein of equine uterine fluid. Forty uterine fluid samples were obtained from 4 mares classified as resistant to uterine bacterial infection. The uterus of each mare was flushed with 50 ml of saline solution during estrus and diestrus of successive estrous cycles. Bacteria or fungi were isolated from 4 samples, and 7 additional samples were obtained from a mare with active intrauterine infection. Fluid volumes obtained during estrus (means = 40.3 +/- 11 ml) tended to be greater than those recovered during diestrus (means = 36.8 +/- 7.9 ml), but the difference was not significant. Concentrations and yields of protein in reco...
Uterine culture in mares. A guarded, sterile swab is used to obtain samples for uterine culture. With the mare in stocks, the tail bandage and the perineum washed, the culture rod is introduced into the vagina with a gloved hand. After the rod is guided through the cervix, the guard cap is dislodged and the swab is rubbed along the endometrium, after which the rod is extracted. Samples for uterine culture should only be obtained during full estrus. Swabs should be directly plated onto agar within 2 hours of collection. Blood agar is appropriate for initial screening, but use of specialized types of agar expedites ident...