In this study, we determined a physiological standard for fibrinogen (Fbg) concentration in the plasma of clinically healthy thoroughbred racehorses trained under sufficient loads for running in races. Furthermore, we examined the usefulness of Fbg levels by comparing them with the white blood cell (WBC) counts in peripheral blood from thoroughbred racehorses diagnosed as suffering from colds or bacterial pneumonia. The Fbg level in healthy horses was lower (246.0 ± 33.1 mg/dl) than previously reported values. On the other hand, both the Fbg levels at the first medical examination and the maximum Fbg levels reflected the severity of the respiratory disorders; therefore, higher Fbg concentrations tended to be related to longer treatment periods. The results suggest that Fbg measurements, both initially and with the elapse of time, can enable the severity of clinical conditions of respiratory disorders in racehorses to be determined and an estimate to be made of the treatment period needed to cure the disease. Therefore, measurements of not only peripheral WBC counts, which have been previously examined, but also of Fbg concentrations permit a diagnosis, based on clinical conditions, of the severity of inflammation that can provide essential information on the pathological states of respiratory disorders, particularly bacterial pneumonia, in racehorses.
We evaluated the effect of laryngeal hemiplegia (LH) on racing performance in thoroughbred racehorses as well as the effects of laryngoplasty on racing performance. A total of 294 racehorses (LH group) were diagnosed with LH were analyzed for this study. A total of 294 racehorses (no-LH group) not suffering from LH extracted at random from the Japan Racing Association population were used for comparison of sex and body weight. The epidemiological investigation evaluated relationships between the occurrence of LH and sex, body weight, the number of the horses that were late for the time limit, the rate of the horse that returned to racing after diagnosis, the number of races run, and race results. Evaluations of the effect of laryngoplasty on racing performance were performed on the rate of the horse that returned to racing after laryngoplasty or no-laryngoplasty, the number of races run, and race results. The ration of males or geldings to female in the LH group was higher than it of the no-LH group. Body weight of the LH group was significantly heavy as compared with it of the no-LH group. It became clear that there is a tendency to suffer the male with heavy weight from LH compared with female. In Grade III, the racing performance was significantly lower than Grade I and Grade II. The racing performance of the laryngoplasty group was higher than the no-laryngoplasty group. It became clear that the horses that have severe LH were poor performance, and laryngoplasty was the useful surgical technique for LH treatment.
Techniques for measuring hydrogen (H2) and methane (CH4) levels in breaths were assessed in horses with gastrointestinal (GI) diseases. A total of 31 horses were studied: 11 healthy horses (Group A), 10 horses with GI diseases (Group B), and 10 horses with diseases without GI involvement (Group C). Expired gases were measured using gas chromatography. CH4 levels in Group A were significantly lower than those in Group B. In Group B, CH4 levels were significantly higher after treatment. Fluctuations in H2 and CH4 levels in breath were associated with changes in GI function.