To clarify the possible factors associated with intra-articular fracture of the lower limb, pathomorphological analysis was done on peripheral nerves, interosseous ligaments and joint capsules surrounding the lower limb joint of the forelimbs of 165 racehorses affected by lower limb fractures and 187 racehorses without fractures. Subclinical changes were frequently found to include ligament degeneration, degenerative joint disease and peripheral neural lesions, which might have been caused by local circulatory disorders and/or vascular alterations. The incidence of lesions seen in the soft tissues was higher in limbs with fracture than in those without. Thus, we speculate that the fractures would occur in limbs with soft tissue lesions, under the influence of resultant incoordination of lower limb locomotion induced by soft tissue lesions when physiological demands are imposed on the limb during training and racing.
A number of palatal abnormalities had been previously reported and these were all diagnosed by utilising nasopharyngeal endoscopy. These included clefts, hypoplasia, cysts, cicatrices and iatrogenic defects of the soft palate. Three cases of defects present in the rostral soft palate which were not diagnosed using routine endoscopy were presented. An oral examination under anaesthetic was required to locate and identify the abnormalities. In two cases, cystic structures were identified and in the other a possible area of palatine hypertrophy was recognised. The abnormalities were treated surgically and post operative assessments suggested a promising outcome.
Morphological changes of the arteries in the ovaries of fillies and mares were studied histologically. The major histological features were intimal thickening due to fibromuscular hyperplasia and medial fibroelastotic changes resulting in narrowing of the vascular lumen. These changes in the vascular structure occurred principally in the regressed corpora lutea and cicatric scars of the corpora lutea of both pregnancy and nonpregnancy, and their degree and extent were severer in the small arteries in the vascular colonies left behind by the regressed corpora lutea of pregnancy compared to those of nonpregnancy. Only rarely were changes of the vessels found in the cortical regions except for those in the regressed and cicatrized corpora lutea. These findings suggest that the hemodynamic effects during the presence of a functional corpus luteum may contribute to or be responsible for the vascular lesions in the ovary.
A rapid colorimetric assay using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) was applied to evaluate equine lymphocyte blastogenic response to mitogens. The optimum concentrations of concanavalin A (Con A), phytohemagglutinin-P (PHA) and pokeweed mitogen (PWM) were 5 μg/ml, 2.5 μg/ml, and a 1:80 dilution, respectively, when lymphocytes were cultured at a concentration of 1 × 106 cells/ml for 5 days in a 96-well microplate. Significant correlations between the results obtained by the MTT assay and the 3H-thymidine incorporation assay were observed. The correlation coefficients were 0.727 (n=68), 0.692 (n=57), and 0.681 (n=44), when lymphocytes were stimulated with Con A, PHA, and PWM, respectively. The MTT assay may be simple and reliable for studying equine cellular immune functions and a suitable alternative to conventional assay systems using radioactive materials.