Veterinary session

Cryopreservation offers significant potential for the conservation of genetic diversity, particularly in rare or endangered species such as chameleons. ARTs, or “Assisted Reproductive Technics” while common in mammals, are rare in reptiles and research on them is often not conducted as deemed less important, and/or less relevant. As far as we know, this is the first attempt to the cryopreservation of chameleon spermatozoa. Researches have been attempted on other reptilian species like the crocodilians and in snakes to try and lead the way to an increased level of research on this particularly interesting field of reptilian reproduction. But the lack of research on chameleons themselves made this study all the more challenging.

Little is known about the ideal protocols for successful sperm cryopreservation in these reptiles, even less in species like the ones treated in this study, namely the veiled chameleon (Chamaeleo calyptratus), the Carpet Chameleon (Furcifer lateralis) and lastly the panther chameleon (Furcifer pardalis). Little is also known on some basic reproductive informations of chameleons, such as the spermatozoa morphology.

This study aims to evaluate the efficacy of three commercially available extenders: Triladyl, Biladyl, and Caniplus freeze, all manufactured by Minitube®; we aimed at evaluating the viability and motility of chameleon spermatozoa post-cryopreservation. Semen samples were collected postmortem from ductus spermaticus from cooled dead animals from captive and wild caught chameleons and subjected to cryopreservation using the respective extenders, followed by thawing and assessment of sperm viability and motility.

From the 9 animals we collected, 4 gave us good enough initial motility to try and proceed with cryopreservation of the samples. The mean live percentage of spermatozoa at collection (fresh) was 88.78 %, which is substantial enough to try the freezing process. It resulted in a mean live percentage post-thawing of 26.88% across all medium of preservation, with the Biladyl and Cani-plus performing best, each with a mean live percentage of 30.8% and 29.3% respectively. These results showed that not only the spermatozoa were able to survive the cryopreservation process but to an extent beyond expectation.

While this study has a number of positive outcomes which encourages us to do more research on the topic, limitation are to be noted. Indeed, no morphological analysis was performed, renders us unable to predict if the live spermatozoa that were recover would be fit for further reproductive uses. Nonetheless, these results should not be overlooked but rather used as a seeping stone for further research on the topic.