Anatomical features of cystic ovaries in cattle found during an abattoir survey.

During an abattoir survey, 8071 bovine genitalia were examined. Cysts of 2-5 cm or larger were found on one or both ovaries in 307, an incidence of 38 per cent. The cysts were arbitrarily classified anatomically into eight groups according to the number present and their texture, whether thin or thick walled, and to the presence or absence of a corpus luteum. The weight and dimensions of the cysts were recorded and any abnormalities of the genital tracts were noted. Ninety-six specimens (30-67 per cent) were associated with a corpus luteum and 217 (69-33 per cent) had no corpus luteum. One hundred and sixty eight tracts (53-67 per cent) had single cysts and in 145 (46-33 per cent) they were multiple. The incidence of multiple ovulations was higher in the cystic ovaries which had corpora lutea than in the non-cystic population. The incidence of ovaro-bursal adhesions in the cystic population was three times higher than in that found in the genitalia which had no cysts and it is possible that this resulted from trauma during rectal palpation.