An epizoological study of wastage in thoroughbred racehorses in Gauteng, South Africa.

Wastage is the term used to describe the phenomenon of the loss of racehorses from conception to adulthood due to death or injuries (i.e. they never reach a race-track), or the days lost by racehorses due to not training or being withdrawn from a race. This epizoological study was conducted to investigate wastage in Thoroughbred horses used for flat racing in the Gauteng Province of South Africa. Data from 6 racing stables were recorded from 1 March 1993 to 28 February 1994. Each trainer completed a daily training record of the horses in his stable. This questionnaire included reasons why a horse failed to train on a specific day, or was withdrawn from a race. During the year, 8480 days (8.1%) of the 105,108 total potential training days were lost by horses in the stables investigated. Of the days lost, 72.1% were due to lameness, 8.6% to respiratory problems, and 19.3% to other causes. The lost training days for the individual trainers ranged from 5.4 to 12.6%. Of the 579 horses included in the study, 291 horses (50.3%) lost one or more training days; 541 problems resulting in wastage were found in these 291 horses; 263 (48.6%) cases were due to lameness and 49 (9.0%) were caused by coughing. The balance were caused by poor weather conditions (11.3%), vaccinations (7.2%), wounds (4.6%), abnormal haematology results (1.8%), inappetence (2.2%), nasal discharge (2.0%), epistaxis (1.8%), babesiosis (1.8%), miscellaneous other conditions (7.9%) and unknown causes (1.8%). An attempt was made to continue the study for a 2nd year but too few questionnaires were returned. However, it was evident that the percentage of lost training days (8.2%) was similar to that of the previous year. The training days lost due to lameness (66.9%) and respiratory problems (8.4%) were also similar to those of the previous year. From the findings of the present study, it was concluded that lameness and respiratory disorders were the major causes of wastage in Thoroughbred racehorses in Gauteng. Further research into these causes of wastage in racehorses is needed.