Hyperplastic polyps seen at sigmoidoscopy are markers for additional adenomas seen at colonoscopy.

Asymptomatic individuals undergoing screening flexible sigmoidoscopy were prospectively studied. Polyps were found in 185 subjects. The endoscopist recorded an opinion on the polyps' histology based on endoscopic appearance. No polyps were removed at sigmoidoscopy. All subjects with rectosigmoid polyps then underwent colonoscopy and polypectomy. Of them, 99 subjects (54%) had at least one rectosigmoid adenoma, 69 (37%) had only hyperplastic polyps, and 17 (9%) had other findings. The endoscopists' opinion of the histopathology of polyps at sigmoidoscopy was correct for 61% of the lesions. Of subjects with adenomatous rectosigmoid polyps, 29% had additional adenomas at more proximal sites. Proximal adenomas were found in 28% of patients with hyperplastic rectosigmoid polyps. Patients with rectosigmoid hyperplastic polyps had the same risk for additional proximal adenomas as patients with rectosigmoid adenomatous polyps.

Genital injuries from mating in the mare.

Minor accidents during natural mating are common occurrences during the breeding of horses. Mares may suffer from a variety of genital injuries including vulval separations, vaginal lacerations and, less commonly, vaginal rupture. Possible sequelae to, and management of, these injuries are described, with additional mention of false entry by the stallion and persistent hymen in maiden mares. Vaginal rupture during natural mating can lead to death of the mare. The implications for litigation involving veterinary surgeons and horse breeders are discussed.

A tubo-ovarian cyst, paraovarian cysts and lesions of the oviduct in the mare.

A tubo-ovarian cyst caused unilateral obstruction of ovum transport in a young Thoroughbred mare. Its effect was a reduction in reproductive efficiency since ovulations from the affected ovary were unproductive. No occluded oviducts were found among 24 pairs of oviducts examined at post mortem. Occlusion of the oviducts in mares is apparently extremely rare. The most common types of cysts found in association with the ovaries in mares are small paraovarian cysts. They are usually found in the fimbriated portion of the oviduct and do not interfere with fertility.

A uterocervical anomaly (Uterus bicorpor bicollis) in a mare, and the manual disruption of early bilateral pregnancies.

A developmental anomaly, resulting from partial segmental aplasia of the Mullerian ducts, was present in a Clydesdale mare. She had complete double cervices and a divided uterine body. In this mare, bilateral pregnancies were destroyed in sequence by squeezing them per rectum 25 and 29 days after insemination.

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 by vaginal speculum examinations, uterine cultures and cytology, and endometrial histology. After an acute inflammatory reaction, each mare had recovered completely within 2 weeks. Most rapid recovery occurred in the mare in estrus at the time of inoculation. Subsequent secondary infections were detected in two mares. The uncertainty of correlations between results obtained by various diagnostic techniques emphasized the problems associated with each. This report illustrates the concept that endometritis in individual mares may relate more to as yet unidentified "mare factors" controlling uterine defense than to primary invasion by bacteria.

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 recovered fluid did not vary significantly with the day of the estrous cycle. Protein concentration was significantly increased in samples from the infected uterus (P = less than 0.001). The ability of uterine fluid samples to attract neutrophils was measured using chemotactic chambers. There was no significant difference between distances migrated by neutrophils toward fluids obtained during estrus or diestrus. Chemotaxis scores tended to be higher with samples from the infected uterus, and the difference was significant for samples from 2 mares. Chemotaxis was neither significantly correlated with protein concentration of uterine fluid, nor with serum estrogens or progesterone.

Mycotic invasion of the mare's uterus.

Uterine infections in three mares following repeated uterine manipulations and antibiotic therapy were caused by Aspergillus fumigatus in two cases and Candida albicans in the third. Two of the infections were noticed during dioestrus and one at oestrus and one mare produced a purulent vulval discharge. Large numbers of neutrophils, increased protein concentrations and the presence of fungal hyphae in flushings from the uterine lumen were indicative of active infection. The mycotic infections caused only transient aberrations of the oestrous cycle and recovery without treatment was completed within 23 days.

Studies on the composition and antibacterial activity of uterine fluid from mares.

Forty uterine fluid samples were obtained during oestrus and dioestrus of successive cycles from 4 mares classified as resistant to bacterial infection of the uterus. The flushings were assayed for peroxidase activity and ability to influence phagocytosis by polymorphonuclear neutrophils. Uterine fluid volumes and protein concentrations and serum oestrogen values were similar during oestrus and dioestrus. Serum progesterone concentrations were depressed during oestrus. Equine neutrophils adherent to glass slides were exposed to a genital strain of Streptococcus zooepidemicus suspended in saline. Neutrophil phagocytosis was significantly higher when cells were incubated with oestrous uterine fluid than with dioestrous fluid. The addition of 5% serum to the incubation medium increased the rates of in-vitro phagocytosis, but these did not differ between oestrus and dioestrus. Rates of phagocytosis with and without serum were not correlated with serum oestrogens or progesterone, or with protein content of uterine fluid. Peroxidase activity of uterine fluid in the absence of infection was negligible throughout the oestrous cycle. There were no significant correlations between peroxidase levels and serum oestrogens or progesterone, but the correlation between peroxidase and protein concentration of uterine fluid was significant (r = 0 X 87). Bacterial or fungal infections led to increased protein content of uterine fluid, and usually marked increases in peroxidase, both probably derived from the visibly obvious populations of leucocytes.

Clinical and structural features of equine enteroliths.

Enteroliths were obtained by laparotomy or necropsy of 11 horses, and a collection of smaller concretions was found on pasture. Following analysis by energy-dispersion x-ray analysis and x-ray diffraction, they were found to consist primarily of ammonium magnesium phosphate. Several minor elements were detected, including titanium in some concretions. From a farm with a history of enterolith obstructions, the well water contained a high proportion of magnesium in relation to the other cations.

Studies on the chromosomes and sex chromatin in the horse.

This study provides accumulated data to assist the definition of karyotypes from normal and infertile horses. The normal karyotype of the horse (2n = 64) was characterized following Giemsa staining and C- banding, and 23% aneuploidy was found among chromosome counts of cells prepared from 44 clinically normal horses and 24 equine embryos. These expected variations in chromosome counts are especially important in the evaluation of potential mosaicism. Centromere staining was shown to be a valuable aid for the identification of specific chromosomes, in particular the sex chromosomes. Sex chromatin studies were applied to nerve tissue and polymorphonuclear neutrophils obtained from three horses. Distinctive sex chromatin bodies were detected in 70% of neurones from a normal mare. The sex chromatin was most frequently located adjacent to the nucleolus. Nuclear appendages ("drumsticks") were present in 4% of polymorphonuclear neutrophils from a normal mare. Small numbers of similar structures were noted in the neutrophils from each animal examined.

A cytogenetical study of prenatal loss in the mare.

The objective of this study was to investigate an hypothesis that chromosome anomalies are an important cause of prenatal loss in the mare. An attempt was made to analyse, cytogenetically, a series of 26 equine abortuses. Cell cultures were prepared from a range of tissues, but failed to grow, and chromosome analysis was therefore not possible for any of these specimens. Consequently, a study was made of the metaphase chromosomes prepared from 22 equine embryos after their surgical removal from mares' uteri. The karyotypes prepared for each specimen were normal. The current findings are discussed in the light of similar studies of induced abortions in women and embryonic loss in animals, and the potential for further investigation in this field is emphasized.

Enteroliths in horses--a retrospective study of 30 cases.

In a retrospective study of selected cases, abdominal colic in 30 horses was attributed to enterolith obstructions of the large intestine. Obstructions caused by "true" enteroliths were confined to horses more than four years old. Prominent clinical features were recurrent mild abdominal pain, inappetance, gaseous distension and minimal intestinal motility. The various aspects of the clinical syndrome, including diagnostic problems and clinical management, are discussed. Most obstructing enteroliths were found near the beginning of the small colon and most horses contained only a single major concretion. Enteroliths were formed by mineral deposition in concentric layers about a central nidus of ingested material and were spherical or tetrahedral in shape. Intestinal concretions were found to consist primarily of ammonium magnesium phosphate.

Colonic obstructions due to enteroliths in four horses.

Four cases of enterolith obstruction in horses aged from six to 14 years are reported. All four cases had symptoms of persistent low grade abdominal pain and anorexia with an absence of defaecation. Examination revealed reduced gut motility and accumulation of gas, but heart and respiratory rates, rectal temperatures and complete blood counts were all within normal limits. Enteroliths of varying sizes were removed from the region of the transverse colon in all four horses.