LAST week, we had started to investigate Rev, a seven year old Collie who had suddenly collapsed mid-stride while out running on the beach.

This previously healthy dog had been rehomed due to a change in his first family’s circumstances and they had reported no health issues when they handed him on to his current owners.

Careful clinical examination had initially offered little to explain the situation. His heart sounded normal. His breathing was easy. His heart and respiratory rates were well within normal limits. His cardiovascular fitness was apparent. There was no evidence of neurological abnormality. He seemed completely recovered from what had seemed at the time to be a life threatening situation.

We noted that he appeared to have been castrated, since there was an obvious absence of testicles in his scrotum. His unusual recent history made it impossible to verify this, but his very lean and muscular body shape suggested that something odd might be going on. And indeed it was.

Careful palpation of his abdomen confirmed the presence of an irregular shaped mass about the size of a large plum, which was situated just in front of his bladder.

His prostate, which in a castrated dog should be small and unremarkable, was enlarged, bi-lobed and slightly uneven, just like you might see in an adult, entire, male dog affected by benign prostatic hyperplasia. But you need the male hormone, testosterone, to cause that and, at face value at least, Rev shouldn’t have been producing any. But of course he was.

Ultrasound scans confirmed the cystic, hyperplastic nature of his prostate and suggested that the mass in his abdomen might be a testicle, albeit a slightly large, unusual one. Careful discussion with his new owners ensued and exploratory surgery was planned for the following day, when, quite literally, all was revealed.

This type of operation is awkward in male dogs, since God, in his wisdom, put the penis exactly where we want to operate. The entry into the abdomen of a bitch is so much easier. In due course, however, Rev was anaesthetised and, with extreme care, the mass was exteriorised.

It proved to be a large, vascular, cancerous testicle. A disruption to its blood supply suggested strongly that it had recently partially twisted around its long axis, a condition called testicular torsion, and this had been the cause of his abrupt and painful collapse on the beach. With some difficulty, the second much smaller testicle was also located deep in the abdomen and removed. Wound closure was routine and recovery was uneventful and complete.

Rev was lucky, indeed. Retained abdominal testicles are ten times more likely to become cancerous that normal, external testicles. Had his not twisted a little, causing collapse, pain and drawing our attention to him, it would have continued to grow and probably spread elsewhere.

By the time he showed symptoms it would have been far too late to do anything much to save him.

With so many dogs now being rehomed and rescued from all over the world, Rev won’t be the only one who looked like he had been neutered, but hadn’t.