Cryptorchidism Figure 1

Figure 1: Cryptorchidism in a 6-week-old male rat.
Case history and photos


A weanling Siamese housed with a small group of males.

Clinical Signs

Left testicle was not descended and could be seen/felt in the lower abdomen. The right testicle appeared normal.


Unilateral cryptorchidism.


Once the rat was old enough, at three months of age, he was neutered. Neither testicle appeared to be diseased.


The young male recovered quickly from his neuter and continues to do well.


unilateral cryptorchidism

The above photos show a six-week-old male rat with one undescended testicle. The white arrow, in the second photo, points to the normal right testis. The black arrow in the last photo shows the undescended testis in the lower abdominal region.

Photography: Joanne “Bella” Hodges


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