pelf-ism is contagious

This is one of the topics I have promised to blog about: the sexing of the river terrapins.

There are quite a few ways to determine the sex of an adult terrapin, for example, from the length of its tail, its overall size and the coloration of its eyes during the mating season. Generally, an adult male river terrapin’s tail is longer and thicker than that of an adult female river terrapin. The male is also usually smaller in size compared the the female. And during the mating season, the male’s eyes turn yellowish-creamish (or whitish) in colour.

But what if we wanted to know the sex of an animal before it matures? Is the sex of the river terrapin dependent on the temperature in which the eggs were incubated, as with the marine turtles?

This is where Dr. Gerald Kuchling and his famous endoscopy technique comes in. Dr. Kuchling is the first scientist to employ the non-sacrificial sexing technique to determine the sex of turtles.

Basically, “endoscopy” refers to the viewing of the inside of a body cavity (e.g. the colon) with an endoscope, a device using flexible fiber optics. And specifically, “laparoscopy” is the direct visualization of the ovaries and exterior of the fallopian tubes and uterus through a surgical instrument inserted through a small incision below the navel.

Before we proceed, let’s take a look at some of the required sexing equipments and chemicals.

On the “operating table”, we have a light source, some syringes, an endoscope, and ample cotton balls.

(From left) Betadine, also known as antiseptic; Ketamil, an anesthetics and surgical wash.

Now, the procedure:

First of all, the terrapin’s hind legs will be tied so that they do not move about and subsequently interfere with the procedure.

Next, the terrapin will be brushed and washed thoroughly using the surgical wash (yes, the same kind of surgical soap used by doctors in hospitals).

Then, a little bit of Ketamil (a type of local anesthetics) will be administered. It is advisable to calculate the the amount of Ketamil used according to a certain percentage of the terrapin’s body weight to avoid anesthetics overdose).

The terrapin is then left for a couple of minutes for the Ketamil to take effect. A few drops of Betadine (antiseptic) is applied onto the “surgical” area.

A small incision is then made with a disposable razor.

This is how the incision looks like:

It is really a small hole, but big enough for the endoscope to pass through, into the body cavity.

The endoscope is then inserted into the terrapin. The peritoneum layer must be punctured before arriving at the body cavity.

Once inside, the endoscope (with an eye-piece on one end and a telescope on the other) is to be carefully maneuvered among other visceral organs so that the vital organs (such as the lungs and heart) are not punctured.

Armed with 25 years of sexing experience, Dr. Kuchling is able to locate a gonad (either a testis or an ovary) in about 15 minutes on the average. Once the sex of the terrapin is confirmed, he will attempt to take a few digital shots of the gonad for future reference.

This is how a terrapin’s testis looks like. It is pinkish in colour, has a smooth surface and is covered with blood capillaries.

And this is how an ovary looks like. It is whitish in colour. It lacks blood capillaries and the rounded follicles are evident.

Finally, the incision is sutured and the terrapin will be kept out of water for at least 24 hours, or until the effects of the anesthetics wear off.

Now that we’re done, any questions? :)