Survey of cystic ovarian disease in practice

Abstract

The "DAISY" computerised recording system (University of Reading) was used to look at records of Cystic Ovarian Disease (COD) over two 12 month periods in a cattle practice in south west England. Over 24 dairy herds with good records were assessed to include 190 cows in year 1 and 180 cows in year 2 presented with COD. A definition of the disease was established as a fluid filled structure on the ovary exceeding 25mm in diameter with no palpable luteal structure present. The economic effect of the disease was compared both within herds and between herds to assess the importance of the condition. At the incidence levels recorded there was no effect on overall herd performance although the condition did affect individuals quite profoundly. Age incidence showed a lower level of COD in 1st lactation animals. Older cows had a relatively constant incidence which followed the age profile of the herds. The overall pregnancy rate was very high (81 - 89%). Treatments consisted of those with and without manual rupture of the cyst, with and without Gonadotrophin Releasing Hormone (GnRH), and with and without Progesterone treatments. Some cases received no treatment at all. The survey showed there was no difference in outcome between treatments involving cyst rupture and those not and that there was no difference between treatment and non treatment involving progesterone or GnRH. GnRH showed a longer interval to subsequent service than rupture or progesterone and there was a lower incidence of recurrence using progesterone treatments. The presenting signs of COD show that in dairy herds with a high level of routine fertility involvement nymphomania or nyphomanism is not common. The clinical presentation of COD in the study herds was 17% at a pre-breeding examination, 58% in cows presented with no observed oestrous, 12% at a negative pregnancy diagnosis, 12% with an irregular heat or service interval. Reviewing data from a variety of veterinary surgeons is difficult. Diagnosis and treatment show considerable bias between operatives and makes it difficult to reach conclusions.