New Test for Horses with Retained Testicles (AAEP 2011)

The team measured anti-Mullerian hormone in the blood to successfully diagnose chryptorchidism.
Share
Favorite
Close

No account yet? Register

ADVERTISEMENT

Ridgling, crypt, cryptorchid. Call it what you want, but a horse with one or two testes that have not descended into the scrotum can present a diagnostic challenge. Anthony Claes, DVM, Dipl. ACT, a graduate student at the University of Kentucky’s Gluck Equine Research Center, discussed a new way to diagnose cryptorchidism during the 2011 American Association of Equine Practitioners convention, held Nov. 18-22 in San Antonio, Texas.

Many stallions can be challenging and even dangerous to handle on a daily basis, especially in the presence of mares. "A horse that displays stallion-like behavior could be a bilateral cryptorchid, a cryptorchid that has its descended testis removed, or a gelding with behavior problems," explained Claes. "Therefore, (horses) thought to be ‘geldings’ that display stallion-like behavior might not actually be true geldings after all. Approximately 3-8% of the male equine population is cryptorchid."

According to Claes, the most common method veterinarians use to diagnose retained testicular tissue in a horse that displays stallion-like behavior involves measuring basal or human chorionic gonadotropin (hCG) stimulated circulating testosterone levels and/or estrone sulphate levels. In previous research Claes and Gluck colleagues had shown that a protein called anti-Müllerian hormone (AMH) is expressed by certain (Sertoli) cells in the testes and can be measured in the blood. They took the research a step further and, in the current study, measured AMH in blood samples from 48 geldings, 44 cryptorchids, and 15 stallions and found:

  • AMH levels were higher in cryptorchids than in either stallions or geldings; and
  • AMH levels were higher in stallions than in geldings.

Other benefits to the new test include "only a single blood sample is required and can potentially be used in cases where testosterone is inconclusive, however more research needs to be done in this area," Claes said

Create a free account with TheHorse.com to view this content.

TheHorse.com is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into TheHorse.com.

Start your free account today!

Already have an account?
and continue reading.

Share

Written by:

Stacey Oke, MSc, DVM, is a practicing veterinarian and freelance medical writer and editor. She is interested in both large and small animals, as well as complementary and alternative medicine. Since 2005, she’s worked as a research consultant for nutritional supplement companies, assisted physicians and veterinarians in publishing research articles and textbooks, and written for a number of educational magazines and websites.

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from TheHorse.com

Sponsored Content

Weekly Poll

sponsored by:

Where do you primarily feed your horse?
278 votes · 278 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with TheHorse.com!