Since I didn't hear back from you and you now appear offline, I do want to leave my thoughts about your wee one.
Now post-castration swelling is not normal but is not uncommon. And when it does occur, there can be a number of causes for it. In regards to how to address this and how long it may be an issue for your wee one will depend on the nature of the swelling. The typical types of swelling we can see in the post-operative period include tissue inflammation, hematomas, hernias (rare), and infection.
Now the most common reason for post-castration swelling is inflammation of the local tissues in response to a surgery having taken place. This type of swelling tends to be mild to moderate and is a normal reaction of the body. This tends to settle within a few days of the operation but can be facilitated with warm compresses and dog safe anti-inflammatories (ie Metacam, Rimadyl, Previcox, etc.) from his vet. Typically, this type of swelling is self-limiting and does not cause further issue.
In regards to the other causes of swellings, when these arise they are considered to be complications rather then a normal tissue response. And when they arise they are often linked to complications in post-operative care of these dogs. This is because it can be difficult to get a energetic young male dog to take it easy after surgery.
When we see hematomas, these often arise when the bouncy young dog has been too active and cause a blood vessel to ooze within the surgery site. And when they do occur they will tend to cause swelling and bruising of the scrotum. These don’t tend to be severe or require surgical intervention, unless blood were freely leaking from the wound. In regards to addressing these, if the ooze is fresh or causing active swelling at the time of discovery, then ice packs can be useful. But if it has been present for a wee while, isn’t actively oozing anymore, and isn’t enlarging, then it would be at a stage where again warm compresses and dog safe anti-inflammatories would be indicated. Like tissue inflammation, hematomas tend to settle within a few days and don’t tend to cause significant issue.
Now unlike the others, infection often requires a bit more ‘inappropriate activity’ from our dogs. Specifically, we most often see post-operative testicular swelling due to infection when the dog has managed to lick the surgical site. The reason why wound licking (or scratching with their feet) is risky is because these provide avenues for bacteria (from the mouth or environment) to gain access into the wound. When this happens, the bacteria fester and cause active infection and swelling (akin to an abscess). In these cases, most of these post-operative infections can be settled with antibiotic therapy.
Overall, post-operative swelling is a common issue after castration of young dogs. Since infection is the most significant risk, it is always ideal to have swellings of this nature evaluated as soon as possible (though this wouldn’t warrant an emergency visit if your dog isn’t actively bleeding and is otherwise well). Therefore, if your dog has a post-castration swelling, I would advise phoning your vet when they are open and having him checked over. Most veterinary practices will even offer free post-operative checks with the vet (or nurse) to make sure that nothing is amiss. And if this is an infection for your wee lad, then antibiotics
can be dispensed to clear this for him.
I hope this information is helpful.
If you need any additional information, do not hesitate to ask!
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