Case Description—A 12-year-old Thoroughbred was examined because of signs of depression, neck stiffness, and poor performance.
Clinical Findings—Physical examination revealed that the horse was dull, appeared depressed, was reluctant to raise its neck and head above a horizontal plane, and had a temperature of 38.5°C (101.3°F). No radiographic or scintigraphic abnormalities of the neck were found; however, high plasma fibrinogen concentration and relative lymphopenia were identified and the horse was seropositive for antibodies against Borrelia burgdorferi. Analysis of CSF revealed neutrophilic inflammation, and results of a PCR assay of CSF for B burgdorferi DNA were positive. Immunologic testing revealed severe B-cell lymphopenia and a low serum IgM concentration consistent with common variable immunodeficiency.
Treatment and Outcome—The horse responded well to do×ycycline treatment (10 mg/kg [4.5 mg/lb], PO, q 12 h for 60 days) and returned to normal exercise. However, 60 days after treatment was discontinued, the horse again developed a stiff neck and rapidly progressive neurologic deficits, including severe ataxia and vestibular deficits. The horse's condition deteriorated rapidly despite IV oxytetracycline treatment, and the horse was euthanatized. Postmortem examination revealed leptomeningitis, lymphohistiocytic leptomeningeal vasculitis, cranial neuritis, and peripheral radiculoneuritis with Wallerian degeneration; findings were consistent with a diagnosis of neuroborreliosis.
Clinical Relevance—Nervous system infection with B burgdorferi should be considered in horses with evidence of meningitis and high or equivocal serum anti-B burgdorferi antibody titers. Evaluation of immune function is recommended in adult horses evaluated because of primary bacterial meningitis.
OBJECTIVE To describe gastrointestinal histologic findings for horses with recurrent colic and evaluate possible associations between initial clinical signs, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge.
DESIGN Retrospective case series.
ANIMALS 66 horses with a history of recurrent colic for which gastrointestinal specimens had been submitted for histologic examination.
PROCEDURES Histologic diagnosis was categorized as inflammatory, neoplastic, ischemic, other, and undiagnosed. Relationships among initial clinical features, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge (ie, alive vs dead and persistent recurrent colic [yes vs no]) and between corticosteroid treatment and outcome were investigated. Odds ratios and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated.
RESULTS Inflammatory disease (36/66 [55%]) was the most common histologic diagnosis. Horses undergoing rectal biopsy alone were significantly (OR, 14.4; 95% Cl, 2.7 to 76.1) more likely to not have a histologic diagnosis than were horses in which other biopsy methods were used. In multivariable modelling, persistence of recurrent colic (HR, 15.2; 95% Cl, 1.9 to 121.2) and a history of weight loss (HR, 4.9; 95% Cl, 1.4 to 16.5) were significantly associated with outcome (alive vs dead) 1 year after surgery. Corticosteroid treatment was not significantly associated with either outcome.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that a high proportion (36/66 [55%]) of horses with recurrent colic had inflammatory gastrointestinal disease. Use of rectal biopsy alone to obtain biopsy specimens was more likely to result in no histologic diagnosis. Use of corticosteroids in horses with inflammatory gastrointestinal disease was not associated with outcome but warrants further investigation.
To compare the application and healing of the zip skin closure system (ZSCS) with sutured closure by use of a split-scar model of ventral midline incisions in horses in a prospective, randomized experimental study.
8 adult horses.
All horses underwent an exploratory ventral midline celiotomy with a standardized 30-cm skin incision. Each horse was randomized to have either the cranial 15 cm closed with suture and caudal 15 cm with the ZSCS or vice versa (split-scar model). Skin closure time was recorded and compared. Photography and skin biopsies were taken preoperatively and 14 days postoperatively. Cosmetic appearance was assessed by use of a proposed equine celiotomy incision score. Healing at 14 days was assessed by histopathology.
Skin closure times were faster with the ZSCS compared to sutured incisions. At 14 days postoperatively, the cosmetic appearance (equine celiotomy incision scores) for ZSCS incisions were better than sutured closure and histologic healing scores were not different between methods of closure. Subcuticular sutures were associated with deep dermal inflammation and necrosis independent of epidermal closure methods.
While limitations to the utility of the ZSCS are recognized, the potential benefits of expedient closure, good cosmetic outcome, and satisfactory healing make this method viable for closure of linear wounds or incisions in horses.
OBJECTIVE To characterize the fecal microbiota of horses and to investigate alterations in that microbiota on the basis of sample collection site (rectum vs stall floor), sample location within the fecal ball (center vs surface), and duration of environmental exposure (collection time).
ANIMALS 6 healthy adult mixed-breed mares.
PROCEDURES From each horse, feces were collected from the rectum and placed on a straw-bedded stall floor. A fecal ball was selected for analysis immediately after removal from the rectum and at 0 (immediately), 2, 6, 12, and 24 hours after placement on the stall floor. Approximately 250 mg of feces was extracted from the surface and center of each fecal ball, and genomic DNA was extracted, purified, amplified for the V1-V2 hypervariable region of the 16S rDNA gene, and analyzed with a bioinformatics pipeline.
RESULTS The fecal microbiota was unique for each horse. Bacterial community composition varied significantly between center and surface fecal samples but was not affected by collection time. Bacterial community composition varied rapidly for surface fecal samples. Individual bacterial taxa were significantly associated with both sample location and collection time but remained fairly stable for up to 6 hours for center fecal samples.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that, for horses, fecal samples for microbiota analysis should be extracted from the center of fecal balls collected within 6 hours after defecation. Samples obtained up to 24 hours after defecation can be analyzed with the realization that some bacterial populations may deviate from those immediately after defecation.