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Patient care report
Reproductive

A case of monorchidism in a domestic rabbit

02 November 2023
Patient Report
7 mins read
02 November 2023
Volume 14 · Issue 9
Figure 1. A lack of scrotal sac and testicle can be observed on the right side, consistent with either cryptorchidism or monorchidism. Clinical examination alone cannot differentiate between the two conditions unless a second testicle can be palpated in the inguinal canal or abdominally.
Figure 1. A lack of scrotal sac and testicle can be observed on the right side, consistent with either cryptorchidism or monorchidism. Clinical examination alone cannot differentiate between the two conditions unless a second testicle can be palpated in the inguinal canal or abdominally.

Abstract

Registered veterinary nurses are often involved in complex, unusual cases found in veterinary medicine and play a large role in aiding the veterinary surgeon to reach a diagnosis. Through academic writing and transfer of knowledge and experience, veterinary nurses should be encouraged by peers to report on unusual cases (that may be left unpublished otherwise), enabling a more significant contribution to the veterinary field and documentation of information that is useful to both veterinary surgeons and nurses alike. In this article, the case of a rabbit with monorchidism is reported, alongside documentation of diagnostic aids used by the veterinary surgeon and clinical outcome.

While cryptorchidism (failure of a testicle or both testicles to descend into the scrotum) is encountered with relative frequency in companion animals, true monorchidism is rarely reported in any species and is limited to isolated case reports. Monorchidism (also known as unilateral anorchidism) is defined as the partial or complete absence of testicular tissue unilaterally, with or without spermatic cord or epididymal remnants and normal genitalia (Lamesch, 1994). The cause of this condition in humans is thought to result from testicular regression, usually as a result of ischaemia from intrauterine torsion (Lamesch, 1994). However, agenesis and ischaemic testicular necrosis have also been proposed as causes in the horse (Gardner et al, 2017). Clinical examination reveals the absence of one testicle and diagnosis in horses and other species is usually achieved through negative identification of the testicle at exploratory surgery/laparoscopy combined with blood hormone assays (Clements et al, 2020). To the author's knowledge, this is the first published case report of monorchidism in a pet rabbit.

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Monorchid
rabbit
castration