BushSnake wrote:Why use ventral scales vs dorsal scales? Is it only because of the ease of clipping? The other sources that I provide DNA data for (mainly lizzards) recommended the tip of the tail for all reptiles. This is far easier to clip, and doesn't hurt the snake, but would that be sufficient?
The other sources recommended a sample about the size of a pin head. Armata / Axel, can you comment on the size of the sample you require?
Most of the DNA is located around the scale base, rather than at the edge, so with ventral scales being larger it is easier to get a clipping which includes some of the appropriate tissue. I also believe people have had problems here in the UK with getting permission to take DNA samples from wild snakes. However, ventral clipping to mark individuals is OK, and if you then want to use the tissue for DNA anaysis that's fine (strange, I know).
Re. sizes of sample: I typically use an approximately 6mmX4mm sized piece of scale for a DNA extraction, which gives a good yeild. However, it's always good to have extra material so subsequent extractions can be done in the future. It's also surprising how little material can be used and still provide sufficient DNA, albeit at lower concentrations. I have successfully done extractions on dwarf Bitis samples from armata that were around 2mmX0.5mm - so sampling should not be limited to just adult/large snakes.
Bushviper wrote:Which parts of the DOR specimen would give the best DNA? Would the heart, liver or just a muscle sliver be the best?
muscle tissue actually gives fairly low yeilds, and in liver samples the DNA can be degraded due to the powerful enzymes contained in the liver. The ideal would be a small section of skin, including the scales and underlying tissues. Tail tips are also fine if this is more convenient.
I will compile all this information into an instruction sheet, so everyone is clear on how to take samples. Oh, and if people have captive WC snakes of known locality, and don't fancy clipping scales, a shed skin would be fine.
Thanks.