Page 205 - Manual of Equine Field Surgery

Cryptorchid Castration 20 I

With the exception of laparoscopic approaches, of the ductus deferens entering the canal indicates

cryptorchid castration is not routinely performed the horse is an incomplete abdominal cryp-

through a flank approach. torchid, is an inguinal cryptorchid, or has a

Laparoscopy is a safe and effective way to iden- descended scrotal testicle.4 Decision to perform

tify and remove abdominal cryptorchid testicles. diagnostic rectal examination is based on the size

Advantages include performing the procedure and temperament of the horse and the anticipated

through small incisions with secure closure, ease surgical approach. Bilateral cryptorchidism occurs

of locating the testicle, and the ability to examine i11 up to 15o/o of cryptorchid horses. These cases

both sides of the abdomen when the side of the may have inguinal, incomplete abdominal, or

retained testicle is unknown, Disadvantages abdominal retention.9

include expense of the equipment and the need to

learn a specialized technique. REFERENCES

1. Dyce KM, Sack WO, Wensing CJG: The urogenital
COMMENTS apparatus. In Dyce KM, Sack WO, Wensing CJG,

editors: Textbook of veterinary anatomy, Philadel-

Geldings that present with stallion-like behavior phia, 2002, WB Saunders.

should have serum testosterone measurements 2. Valdez H, Taylor TS, McLaughlin SA, Martin TM:

before and 30 to 120 minutes after the adminis- Abdominal cryptorcliidectomy in the horse using

tration of at least 6000 IU human chorionic inguinal extension of the gubernaculum testis, J Am

gonadotropin (HCG) intravenously to determine Vet Med Assoc 174:1110, 1979.

if testicular tissue is present. Geldings have serum 3. Adams OR: An improved method of diagnosis and

testosterone levels of less than 40 pg/ml. Cryp- castration of cryptorchid horses, J A1n Vet Med

Assoc 145:439, 1964.
torchids have serum concentrations of greater 4. Adams SB, Fessler JF: Noninvasive inguinal cryp-

tha11 lOO pg/mL.8 Horses younger than 18 months torchidectomy. In Adams SB, Fessler JF, editors:

or horses tested during winter may respond Atlas of equine surgery, Philadelphia, 2000, WB

poorly to HCG and may need to have an addi- Saunders.

tional sample tested 24 hours after HCG admin- 5. Wilson DG, Reinertson EL: A modified parain-

istration or be retested when older or during tl1e guinal approach for cryptorchidectomy in horses.

spring.9 Previous surgical exploration often makes An evaluation in 107 horses, Vet Surg 16:1, 1987.

identification of surgical landmarks difficult, and 6. Bladon B: Surgical management of cryptorchidism

when the side of cryptorchidism is not known, in the horse, In Practice 24: 126, 2002.

surgery can be prolonged. In these situations, 7. Cox J: A surgical approach to the cryptorchid

laparoscopic exploration of the abdomen is the horse, In Practice 10:11, 1988.
8. Cox JE: Cryptorchid castration. In McKinnon AO,

recommended approach. Voss JL, editors: Equine reproduction, Philadelphia,

Left cryptorchid testicles are more likely to be 1993, Lea & Febiger.

abdominal, whereas right cryptorchid testicles are 9. Mueller EPO: Cryptorchidism. In Wolfe DF, Moll

more likely to be inguinal." Rectal examination of DH, editors: Large animal urogenital surgery,

the inguinal region may also be useful in deter- Philadelphia, 1999, Williams & Wilkins.

mining the location of the testicle. Horses with 10. Stickle RL, Fessler JF: Retrospective study of 350

abdominal testicles will have a small or indis- cases of eq uine cryptorchidism, J A1n Vet Med Assoc

cernible inguinal ring. A larger ring with evidence 172:343, 1978.

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