Results of physical inspection before races and race-related characteristics and their association with musculoskeletal injuries in Thoroughbreds during races.

OBJECTIVE: To estimate the relative risk of injury among horses deemed to be at increased risk of injury on the basis of prerace physical inspection findings and to examine the association of injury during races with race-related characteristics. DESIGN: Cohort study. ANIMALS: 2,187 Thoroughbred horses that started 3,227 races in Kentucky. PROCEDURE: All race starts for which a horse was deemed to be at increased risk of injury on the basis of prerace physical inspection findings and a random sample of race starts for which horses were not deemed at increased risk of injury were included in the study. Findings of prerace physical inspection, race-related characteristics, and outcome of the race (race results and whether the horse incurred an injury) were recorded for each race start. Race starts in which a horse incurred an injury during a race were compared with race starts in which injuries were not incurred to identify factors associated with injury during races. RESULTS: Abnormality of the suspensory ligament of the forelimbs detected during prerace physical inspection, racetrack, class of race (claiming race < or = $25,000 vs other classes), and distance of race (< 7 furlongs vs other distances) were significantly associated with increased risk of injury. CONCLUSIONS AND CLINICAL RELEVANCE: Prerace physical inspection findings, particularly abnormalities of the suspensory ligament, may be used to identify horses at increased risk of injury during races. Rate of injury differed among racetracks, and horses in certain types of races (lower-priced claiming races and races of shorter distance) may be at increased risk of injury during races.

Transmission of enteritis in the Syrian hamster.

Twenty-six of 39 Syrian hamsters obtained by this laboratory from a pet supplier had enteritis and showed signs of "wet tail." An enteritis was reproduced in healthy hamsters by oral inoculation of homogenized ilea and jejuna from the diseased hamsters. The most characteristic pathologicfeatures were a variably enlarged distal jejunum and ileum and granulomatous lesions in the ileal subserosal wall. Histologic findings included a greatly hyperplastic jejunal and ileal mucosa that frequently contained submucosal accumulations of inflammatory cells. Often mucosal glands extended into these areas. The gross and histologic lesions produced were identical to those described in proliferative ileitis. Bacterial cultures from infected tissues consistently grew a slow lactose-fermenting Escherichia coli. Although diarrhea could be produced by oral inoculation of the organism, the typical morphologic lesions were not produced.

A survey of naturally occurring diseases of the Syrian hamster.

Questionnaires on research activities, mortality rates observed in various age groups, extent of examination of dead hamsters, and natural disease conditions and their relative importance were returned by 24 of 43 organisations surveyed in the United States. The average preweaning mortality rate due to all causes was 11-9%. Comparative data from 6 organisations that raised 87 880 hamsters in the calendar year 1971 indicated that 97-5% of total preweaning mortality was due to cannibalism. 13-7% of all animals died before use for experiments. "Wet tail" was the most frequently recognized disease (71%), and it was also listed as the most important. Pneumonia was recognized by 43% of the respondents and was most commonly listed as second in importance. A selective review of the literature is presented on those diseases recognized by more than one survey respondent.