Ovarian Cyst Treatment for a Mare

Cysts

• A cyst can contain fluids, air or semi-solid membranes. It is a closed sac. A cyst is not an abscess. An abscess is a compilation of pus. Sometimes cysts go away without intervention and sometimes surgery is required to remove them. Cysts are often found in mares during a routine examination. These cysts are common and do not usually interfere with fertility. However, interference is possible if the cysts obstruct the ovulation process, which entails the transport of the oocyte into and through the oviduct. An oocyte is an immature female cell sex that eventually matures into an ovum. If this process does not happen, a pregnancy is not going to occur. When a mare has fossa cysts or fimbrial cysts that are not causing any problems with the ovulation process you do not need to treat the cysts, according to Patrick M. McCue of the Colorado State University Equine Production Laboratory.

Cystadenoma

• Cystadenomas are the most common surface equine ovary cyst. Veterinary surgeons remove this type of cyst, as they can metastasize and cause the mare pain. Mares can have cystadenomas with increased plasma testosterone concentrations, but tumors of this nature are generally rare and benign and usually are not active hormonally.

Granulose Cell Tumors

• One of the most frequent problems with the ovaries of mares is the presence of a granulose cell tumor. These are benign, slow growing and unilateral. The cyst has a

  honeycomb structure or is multi-cystic, but it can also be one large single cyst or a solid mass. The vet can detect an enlarged ovary by palpating the rectum. A sonogram can determine the number and size of cysts within the tumor. The ovary should be removed via surgery. Mares resume their estrous cycle about six months following the removal of one ovary.

Preparing for Surgery

• Antibiotics are administered before the mare undergoes surgery, and she should be kept on the antibiotic regimen for five days afterward. The mare also receives an epidural before the vet begins the operation. Placing the mare in stocks prevents her from moving during surgery, and her tail is placed in a tail wrap. Her bladder is emptied via a urine catheter and feces are removed from her rectum to ensure against evacuation during surgery. The method of removing the ovary depends on the temperament of the mare, the size of the ovary and the experience and preferences of the surgeon. One option is to leave the mare standing, using a local numbing agent for anesthetic purposes. General anesthesia is used if the vet decides to operate while the mare is lying down.