A dorsal approach for the removal of the nasal septum in the horse.

OBJECTIVE: To describe and evaluate a technique involving a dorsal approach for the removal of the nasal septum in adult horses. STUDY DESIGN: Retrospective clinical study. ANIMALS: Four client-owned horses. METHODS: Access for partial nasal septum resection was through a dorsal nasal bone flap. Septum resection was performed because of reduced airflow from septal deviation and/or thickening caused by traumatic insult or neoplasia. Preoperative clinical signs and diagnostic results were recorded. Intra- and postoperative complications were noted and follow-up information was obtained from telephone interviews of owners or by clinical examination. RESULTS: The abnormal segment of the nasal septum was completely removed in all horses. A dorsal nasal bone flap approach provided excellent access to the septum and allowed immediate control of hemorrhage; blood transfusion was not needed. Cosmetic results were considered good to excellent by owners and horses returned to their previous level of work without perceived limitations associated with airway function. CONCLUSIONS: Nasal septum resection by the dorsal approach permits good observation of the abnormal septum, and provides exposure that facilitates removal of nasal masses and reduction of depression fractures with minimal complications. CLINICAL RELEVANCE: A dorsal nasal bone flap approach should be considered for horses that require nasal septum resection because it can be achieved with minimal hemorrhage, good cosmetic results, and return to function.

Hematology of equine fetuses with comparisons to their dams.

The Hematologic values of 19 equine fetuses between 202 and 238 days gestation were compared with those of their dams. The red blood cell (RBC) count, hemoglobin concentration, hematocrit, and mean corpuscular hemoglobin concentration were significantly lower in fetal blood, while the mean corpuscular volume, mean corpuscular hemoglobin, and red cell distribution width were significantly higher. Mares had a significantly higher nucleated blood cell count than fetuses, and all nucleated cells were leukocytes (WBC). Most WBC in mare blood were segmented neutrophils and lymphocytes. In contrast, over one-half of the nucleated cells in fetal blood were nucleated RBC, and the majority of WBC in fetal blood were lymphocytes. Mares also had significantly higher plasma protein and fibrinogen concentrations than their fetuses. Mild macrocytosis and mild polychromasia were observed in most fetal blood samples, but not in blood samples from mares. All fetal blood contained reticulocytes, and most samples contained Heinz bodies and Howell-Jolly bodies. The results of this study will contribute to the development of hematologic reference values that may be useful in equine fetal research and, possibly, in the diagnosis of equine fetal disease.

Effects of delayed serum separation and long-term storage on the measurement of thyroid hormones in equine blood samples.

Studies were conducted to determine the effects of delaying the separation of serum from the clot and of long-term storage of serum samples on the measurement of thyroid hormones in blood from horses using a fluorescence polarization immunoassay. The measured concentrations of T3 and T4 were not affected by leaving serum on the clot for as long as 24 hours at room temperatures. Storage of serum for 19 to 22 months at -20 degrees C resulted in significant increases of measured T4, but not T3. These studies support previous work demonstrating that thyroid hormones are resistant to degradation, immunologically stable, and reasonably insensitive to potential problems of routine specimen handling when measured with an immunoassay.