SummaryReason for performing study: An understanding of the normal events of foaling, causes of dystocia and clinical outcomes is important for equine practitioners. Objectives: The goals of the present study were to: 1) evaluate factors that influence gestation length; 2) report duration of Stage II labour; 3) determine the frequency of dystocia and premature placental separation; and 4) determine the relationship between problems at foaling and foal survival. Materials and methods: Foaling records of 1047 mare births were evaluated. Results: The average gestation length was 341 Ϯ 0.3 days, with no effect of mare age or breed observed. Mares carrying male fetuses had a longer gestation (PՅ0.001) than mares carrying female fetuses. A majority (52.8%) of mares foaled at night between 2000 h and 0200 h when the facility was quiet. Dystocia occurred in 10.1% of all births and the incidence rate was higher in Thoroughbred mares than in Quarter Horse mares. The most common cause of dystocia was abnormalities of fetal posture. A delay in foal delivery beyond 40 min of Stage II of labour was associated with a significant increase in foal mortality. In addition, an increase in foal morbidity and mortality was noted when the interval from birth to standing or birth to nursing was prolonged. Conclusion: Early detection and rapid appropriate intervention are critical to foal survival in an equine dystocia. Potential relevance: Equine veterinarians should counsel horse owners that early recognition of a foaling problem and rapid, appropriate intervention are critical to the survival of a foal.

Positive blood cultures suggest transient bacteraemia may occur in healthy foals early in the post natal period. Age corrected normal values may be necessary to interpret cytokine concentration in diseased populations.

Background: Granulosa cell tumours (GCT) are the most common ovarian tumours in mares. While the classical presentation may not represent diagnostic challenges, diagnosis is not easy in the early stages. Objectives: Illustrate the variability in the presentation and serum biomarkers associated with ovarian abnormalities in the mare. Study design: Retrospective case series. Methods: Nonclassical cases of GCTs and other ovarian conditions were identified and behaviour, GCT endocrine results, palpation and ultrasonographic findings are described and the diagnostic value of each is discussed. Results: Mares in this case series with GCTs had been presenting clinical signs ranging from no behavioural changes to behaviours including aggression, stallion-like and inability to work under saddle. Hormonal profiles of endocrinologically functional GCTs can be erratic and unpredictable. The clinical form and ultrasonographic appearance may also vary with time from an initially enlarged/anovulatory follicular structure that later develops a multicystic 'honeycomb' appearance. Mares with GCTs can also present with persistent anovulatory follicles or apparent luteal tissue that are unresponsive to treatment. If both ovaries are of relatively normal size and symmetry, but hormonal biomarkers are markedly increased (AMH >10 ng/mL, inhibin B and/or testosterone >100 pg/ mL; 0.37 nmol/L), it is likely that a functional GCT is present. Still, it can be a challenge to decide which ovary to remove. Post-surgical endocrine testing can be helpful, especially if histopathology is not performed or a GCT is not found. Main limitations: Cases limited to 14. Conclusions: Granulosa cell tumours present with a wide variety of clinical signs that do not fit what is commonly described as 'classic'. Only if AMH, testosterone and inhibin B concentrations are markedly increased, and there is an abnormally enlarged ovary, the diagnosis of a GCT is more confident. In the presence of normal size ovaries, normal hormonal biomarkers and abnormal behaviour, it is more likely that the ovaries are not involved. | 61 RENAUDIN Et Al.

In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CFU of E. coli isolates, K. pneumoniae isolates were observed to have a reduction in CFU, and minimal effects were observed for P. aeruginosa isolates. Chelating agents (EDTA formulations) reduced E. coli CFU but were ineffective at disrupting preformed biofilms or decreasing the CFU of P. aeruginosa and K. pneumoniae within a biofilm. No single nonantibiotic treatment commonly used in equine veterinary practice was able to reduce the CFU and biofilm biomass of all three Gram-negative species of bacteria evaluated. An in vivo equine model of infectious endometritis was also developed to monitor biofilm formation, utilizing bioluminescence imaging with equine P. aeruginosa isolates from this study. Following infection, the endometrial surface contained focal areas of bacterial growth encased in a strongly adherent "biofilm-like" matrix, suggesting that biofilms are present during clinical cases of infectious equine endometritis. Our results indicate that Gram-negative bacteria isolated from the equine uterus are capable of producing a biofilm in vitro, and P. aeruginosa is capable of producing biofilm-like material in vivo. Bacterial endometritis is an important cause of subfertility in mares (1). Endometrial infections are reported in 25 to 60% of mares who fail to become pregnant following breeding (1), contributing to a major economic loss for the equine industry (1, 2). The most common species of bacteria identified during the clinical diagnosis of bacterial endometritis include Streptococcus equi subsp. zooepidemicus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa (3, 4). The isolation of one of these species of bacteria is considered to be clinically relevant due to observed reductions in pregnancy rates after identification (2). The detection of these bacteria in the uterus would result in treatment with uterine lavage and broad-spectrum antibiotics to reduce bacterial load and eradicate the remaining bacteria (5, 6).Bacterial endometritis that is refractory to traditional antimicrobial treatment is a significant challenge in the equine breeding industry (4). One possible explanation often cited for the failure of antibiotic treatment is the growth of bacterial pathogens in a biofilm (1, 5). Uterine isolates of E. coli, P. aeruginosa, and K. pneumoniae have been proposed to most likely be associated with a biofilm, due to the observation of repeated antibiotic treatment failures in equine reproducti...

All sampling techniques can be adequate methods for endometrial cytology, but the brush technique consistently provided the best sample. Sample contamination or poor slide quality can adversely affect interpretation. The most accurate criteria for determining what constitutes mild endometritis in mares have yet to be established.