singapore rabbits

testicular cancer in unneutered seniors

updated 19 May 2026

most rabbit owners in Singapore keep unneutered males. exotic vet surgery is expensive here, and many owners have a solo male rabbit with no visible behavior problems. the reasoning is understandable. what is less visible is the quiet risk building inside the testes as that rabbit ages. testicular cancer is one of the most preventable tragedies in SG rabbit ownership, and one of the most commonly missed. Singapore’s year-round heat and humidity (28-32°C, 70-90% RH) compound the risk for older rabbits whose systems are already under thermal stress. add to that the limited number of exotic vets compared to cat and dog clinics, the difficulty of getting an urgent appointment, and the fact that rabbits mask pain instinctively, and you have a situation where early awareness matters more than almost anything else.

what testicular cancer actually is

testicular cancer in rabbits develops as a tumor within one or both testes. the most commonly reported type is an interstitial cell tumor, also called a Leydig cell tumor. these originate in the cells that produce testosterone. other types include Sertoli cell tumors and seminomas, each with different behavior and spread patterns. some are benign and grow slowly without spreading. others are malignant and can metastasize to the abdomen, liver, or lymph nodes. you cannot distinguish benign from malignant by visual inspection or touch alone. that determination requires imaging and, often, histopathology of the removed tissue. what matters practically is this: any testicular swelling in an adult rabbit requires a vet, not a waiting period. the biology of the tumor type is something the vet determines after examination, not something the owner can assess at home.

which rabbits are most at risk

risk increases significantly after age three and is highest between ages four and eight, though younger cases occur. all intact male rabbits carry some baseline risk, regardless of breed. in Singapore, the pet rabbit population includes a large number of unneutered males aged two to six who have never had a veterinary scrotal examination. if you adopted from a pet shop without neutering guidance, that is almost certainly your rabbit’s situation. if you adopted from a rescue that required neutering before rehoming, your rabbit’s risk from this specific cancer is eliminated entirely. if you are unsure whether your rabbit was neutered, a vet can confirm this in seconds during a physical exam. do not assume. ask your vet at the next visit and get it noted in the record.

signs to watch for

early testicular cancer has no obvious symptoms. your rabbit may eat well, move freely, and seem completely normal while a tumor grows for months. this is why monthly physical checks at home are worth building into your routine. during a check, look and feel for:

  • one testicle noticeably larger than the other
  • a firm, hard, or irregular lump you can feel through the scrotal skin
  • skin discolouration over the scrotum: redness, darkening, or obvious asymmetry between sides
  • your rabbit grooming or pawing at the groin more than usual
  • flinching or reluctance when the belly or groin area is touched
  • reduced activity, or more time spent in a hunched position
  • in later stages, visible weight loss or abdominal bloating

any swelling, firmness, or asymmetry in the testicular area is a reason to schedule a vet visit that week. do not wait to see if it resolves. it will not resolve on its own.

when to treat it as urgent

most testicular tumors grow slowly, but certain signs require same-day or next-day action. contact a SG exotic vet immediately if you observe:

  • a sudden swelling that appeared within 24 hours
  • the scrotum is red, warm to touch, or has broken or weeping skin
  • your rabbit is not eating and is sitting hunched with audible teeth grinding
  • visible rapid weight loss over a few days
  • the abdomen is distended or tense to gentle touch

Singapore has limited after-hours exotic vet coverage. keep a 24-hour clinic number that accepts exotic species in your phone before you ever need it. the Animal and Veterinary Service (AVS) website lists licensed exotic vet practices. a sudden swelling late on a Friday night is not the time to start researching your options.

what to expect at the vet

a SG exotic vet will start with a hands-on physical examination of both testes and the abdomen. next steps typically include:

  • blood panel: checks liver enzymes, kidney markers, and blood cell counts to assess anesthetic risk before any procedure
  • X-ray or ultrasound: to assess whether the tumor has spread beyond the testes into the abdomen
  • fine needle aspirate (FNA): sometimes done to sample cells from the mass before committing to surgery; results are not always conclusive in rabbit tumors

if the tumor appears localized, the vet will recommend castration, which removes both testes. even if only one side is visibly affected, both are typically removed to eliminate risk on the apparently healthy side. as of 2026, castration at a SG exotic vet typically ranges from SGD 250 to SGD 600 for a straightforward case. a senior rabbit needing extended pre-op workup, IV fluids, or additional monitoring will likely fall at the higher end or above.

surgery, recovery, and prognosis

castration for testicular cancer is the same surgical procedure as a routine neuter, but in a rabbit over four years old anesthetic risk is meaningfully higher. a vet will want bloodwork confirming that kidneys and liver can handle the anesthetic load before proceeding. the surgery itself typically completes in under an hour for uncomplicated cases.

post-operative recovery requires close attention in Singapore’s climate. heat and humidity slow incision healing and raise infection risk. keep your rabbit in an air-conditioned room, targeting below 26°C for the first week. check the incision site twice daily for redness, swelling, or discharge. offer hay, fresh water, and leafy greens in the first 48 hours; appetite often drops after anesthesia. if your rabbit has not produced droppings within 12 hours of arriving home, call the vet. GI stasis is a serious risk whenever a rabbit stops eating, and it escalates quickly.

prognosis for localized tumors detected early is generally good after surgical removal. malignant tumors that have spread to other organs carry a more complicated outlook, depending on what was affected and how extensively. early detection is the single biggest factor in your rabbit’s outcome.

what owners often get wrong

waiting for obvious pain signals. rabbits are prey animals. displaying pain openly signals weakness and vulnerability. your rabbit can appear healthy, eat normally, and binky regularly while carrying a significant tumor. normal behavior is not a clean bill of health. monthly physical palpation of the scrotal area is the only reliable home check.

assuming testicular swelling will go down. testicular swelling in adult male rabbits does not resolve without intervention. it grows. owners sometimes post photos in Facebook groups or Telegram chats and receive replies from others saying their rabbit had something similar and it cleared up. those anecdotes are almost never accurate. waiting several weeks for crowdsourced reassurance is several weeks of potential tumor growth.

treating neutering as purely a behaviour fix. many SG owners are told to neuter to reduce spraying or territorial aggression. when their rabbit is calm, they skip it. the cancer prevention argument is the stronger one for any intact male over three. temperament has nothing to do with testicular cancer risk. a perfectly behaved rabbit can still develop a tumor.

skipping annual wellness visits because the rabbit seems fine. dogs and cats get routine annual checkups as standard practice. rabbits rarely do. a once-yearly exotic vet visit includes a physical exam that catches testicular asymmetry long before you would notice it at home. it is the best early-detection tool available to you, and it is entirely passive on your part.

community-sourced information here is not veterinary advice. for any health concern see a licensed SG exotic vet.

community-sourced information, not veterinary advice. for medical issues, see a licensed SG exotic vet — start with our vet directory.

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