Some clinical and surgical aspects of the cryptorchism were investigated in 42 horses. Cryptorchism had a high frequency in Mangalarga, Quarter Horse, and mixed breed, 73.8% of the cases. Abdominal cryptorchism was more prevalent than the inguinal, 64.3% and 35.7%, respectively. The unilateral retention occurred in most cases (95.2%), with a high frequency of left abdominal cryptorchism (45.2%). The serum testosterone levels were also determined in six normal stallions (control group) and 10 cryptorchid horses (five abdominals and five inguinals). Serum testosterone concentration showed no difference (P> 0.05) among groups. The production of this hormone did not change in the cryptorchism, therefore, justifying the similar sexual behavior of the cryptorchid horse and normal stallions.
cryptorchism; testosterone; horse