Neuter Figure 2

Figure 2: Castration/neuter in 5-month-old male to reduce unwanted aggression and prevent mating (Joshua).
Case history and photos


Joshua was adopted as a single intact male rat from a local animal shelter in December 2009 (he had been found wandering the streets). He was guessed to be about 5 months old at the time.

Clinical Signs

Arrangements were made to adopt two to three additional male rats from a local rat rescue, of approximately the same age or younger. However, during a brief introduction attempt at the rat rescue, Joshua appeared too dominant to tolerate even castrated male companions.


The rat rescue advised having Joshua castrated, so that he could be introduced to intact female rats.


Joshua was castrated on 20 January 2010, using injectable anesthetic medetomidine (Domitor) and an injectable painkiller (Carprofen) that would last for 24 hours, after which oral administration of Carprofen was to be continued for four days. The incision site was closed by means of a combination of surgical adhesive and sutures. The surgery went well. Joshua remained quite sedated for two days post-op, presumably due to the injectable anesthetic. He was, however, eating normally, although not as eagerly as he normally did, so this was not considered to be a reason for concern.


Joshua healed well, although there was some initial swelling of the scrotum, making it appear as if the testicles had not been removed during surgery. Over the course of a month the scrotum gradually decreased in size. Joshua removed only one of his stitches; the remainder were removed by the rat rescue.


A month and a half after his castration, Joshua was successfully introduced to three intact female rats. When Joshua was 1 year and 7 months old, two castrated 4-month-old male rats were successfully added to the group.



Row 01: The photo on the left shows Joshua shortly after his adoption, with an intact scrotum. The photos on right show Joshua fully healed, almost two months after his castration, during his “love at first sight” introduction to Yasmine (beige hooded intact female rat).


Row 02: These photos were taken, respectively, on days 1, 11, and 31 post-castration. They show increased healing of the incision site (closed by means of a combination of surgical adhesive and sutures) as well as “shrinking” of Joshua’s scrotum.

Case history and photos courtesy of Cyzahhe


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