The reproductive and ovulation physiology of tegus (Tupinambis species).

[lovingrush]

Hi everyone, I’m a tegu keeper from Taiwan, and I have a question I’d really love your input on.

Recently, my female red tegu laid eggs. They were infertile (slugs), but what confuses me is that she’s never been through brumation and is kept in a warm, stable environment all year round. Despite that, she still ovulated and laid eggs.

So my question is: do some females just absorb the eggs while others choose to lay them?

I also have a female black and white tegu under the same year-round warm conditions, and she’s never laid eggs. Could that be because she’s never had the seasonal cues from brumation? Or is it because she hasn’t had a mate and her body doesn’t see a reason to ovulate?

I’m trying to understand what really triggers ovulation in tegus—is it mainly temperature/light changes, or the presence of a potential mate, or some kind of internal biological rhythm?

Here are a few examples from my experience and from local breeders here in Taiwan:

Case 1: A 7-year-old large female B&W tegu has never laid eggs, even with brumation.

Case 2: Out of six tegus that were all brumated, only one ended up laying.

Case 3: A female red tegu, about a year and a half old, kept warm year-round, laid eggs without ever brumating.

Some experienced breeders here have shared that tegus can still enter a reproductive cycle and lay eggs even without brumation. They say it’s a combination of environmental cues and their internal biological clock, not just brumation alone. Brumation just helps regulate and synchronize the hormonal cycle—it’s not the only trigger.

Thanks so much for reading, and I’d really appreciate any insights or experiences you’re willing to share!

 

[lovingrush]

Tegus don't have to Brumate to ovulate, though it's random when they ovulate if not brumated. With no brumation they can ovulate in the middle of winter (opposite to when they naturally ovulate) or during summer. The rarity of a female laying eggs and never being bred is EXTREMELY rare with tegus unlike monitors. Though it is possible, it's very rare. And yes females can fully absorb their eggs which is also rare in itself, as most reptiles that don't lay their eggs will just become egg bound and usually die. Tegus on the other hand fully absorb them with no trace of them when they lay their next clutch, no mumified eggs or anything. Generally a female will ovulate, and if there's no male to breed them they will absorb them before they ever become actual eggs. Absorbing an actual developed clutch of eggs is much harder on their body and it takes them longer to recover from this than it does actually laying the eggs. When they lay eggs they have their appetite back within 2 days on average and eat voraciously which makes them gain weight back fast. When they absorb the clutch they don't get a regular appetite back for many weeks and it ends up taking much longer for the female to pack muscle and reserves back on.