Cystic ovaries may have a low incidence in most herds - typically between 1% and 4%-but they have a big impact on cow fertility. Affected cows can be difficult to treat, and anecdotal evidence says only 30-50% of treated cows recover and go on to achieve a successful pregnancy. So they are often culled for failing to conceive. Not much is known about cysts because the ovary is a very complicated organ regulated by several hormones. But we define a cyst as a fluid'filled structure on the ovary that is more than 2cm in size, occurring at least six weeks after calving and persisting for more than 10 days.
展开▼
