|MadSci Network: Zoology|
I did not find any reference to a white line on an egg. I did find some good information on turtle husbandry. The basic requirements for most reptile incubators are: well-insulated, evenly dispersed heat and humidity, and no hot spots. Vermiculite, potting soil, sand, sphagnum moss, and shredded paper are good substrates for the eggs to rest in. Heating coils, strips, and pads work well to keep the incubator warm. Monitor the temperature by placing a thermometer along side the eggs. The correct temperature depends on the species of turtle you are raising. In general, the warmer the incubation temperature, the shorter the gestation period. Most eggs hatch in two to three months. Water is added to the substrate to make it very moist, but not liquid. Cover the tops to prevent drying out. Mist the tops with water daily. A slight mottling to the surface of the egg may not be significant; however, marked changes in color or texture, or growth of fuzzy mold usually indicates that the egg has either died or was nonfertile. Egg viablility can be easily checked using a high intensity light source. Placed in direct contact with the side of the egg in a darkened room. Egg viability can be confirmed by the presence of a developing vascular pattern as the embryo grows. The actual process of emergence from the egg takes from 24 - 48 hours. If hatching does not occur within the appropriate time period, the embryo will die. It is imperative that the eggs are monitored while hatching. Reptile Medicine and Surgery; Mader, Douglas R. From the web: Water Turtle Eggs ====================== * If your water turtle has laid eggs in the water, and you didn't remove them within a couple of hours, the eggs are probably dead. The reason is that the eggs are deprived of oxygen and they die. * If your female turtle has not seen a male for more than two years, then the eggs are probably infertile. Fertile eggs are usually covered with a sticky mucus. 1. Remove eggs after laying. DO NOT TURN OVER THE EGGS. (It is OK to mark the top with a magic marker or a bit of charcoal). 2. Incubate in a box with moistened Vermiculate (equal parts of water and vermiculite BY WEIGHT). You get Vermiculate at garden centers. Make small depressions into the vermiculite and an gently position the eggs. If eggs stick together, you may try to separate them, but if they don't come apart easily, it's better to just leave them alone. Refer to the sheet on breeding turtles for more information. Box Turtle Eggs =============== * If your water turtle has laid eggs in the water bowl, and you didn't remove them within a couple of hours, the eggs are probably dead. * If your female turtle has not seen a male for more than three years, then the eggs are probably infertile. However, box turtles have been known to keep sperm around for longer than that. 1. Remove eggs after laying. DO NOT TURN OVER THE EGGS. (It is OK to mark the top with a magic marker or a bit of charcoal). 2. Incubate in a box with moistened Vermiculate (equal parts of water and vermiculite BY WEIGHT). You get Vermiculate at garden centers. Make small depressions into the vermiculite and an gently position the eggs. If eggs stick together, you may try to separate them, but if they don't come apart easily, it's better to just leave them alone. You can also use Shagum moss as the incubation medium. Bury the eggs into the sphagum moss and keep it moist (not soggy). Refer to the sheet on breeding turtles for more information. More on Incubation (From a Turtle Homes Member) =============================================== For my Box Turtles and water Turtles I place the eggs on moist papertoweling which covers the bottom of a clean pie tin. I cover the eggs with paper toweling and maintain a moist condition throughout the growing period. It is easier for me to allow 12 hour natural drying and then wetting by hand. I can also have easy access to the eggs for observation all the time. When I see any sign of mold, I carefully wipeand rinse the eggs while maintaining UP position of the eggs. My eggs always have clearly defined hemispherical real white on top half and wetter looking white on the bottom half of the egg shells making TOP easy to determine if movement occurs in error. If you over water the eggs can drown! Paper toweling is clean off the fresh roll. If an Egg Cracks or Bursts ========================== Usually, when eggs burst, which can happen, and you didn't do anythying wrong if the other eggs are fine, you can either do nothing if the crack is very small (which is what I did with mine just the other day; it has a very small crack because it was removed surgically) and the seeping egg white will dry and seal the egg. Just keep the egg in extra sterile conditions. (Vermiculite is a (relatively) sterile substrate, or cotton wool.) I know of people who have sealed cracked eggs with superglue successfully. If your other eggs are fine, this may just have been one that wasn't so good. It happens. And, I also know of perfect babies coming out of broken eggs. Most important: keep moist enough, so egg doesn't dry out. Use sterile water for this egg. I would also separate this egg from the others. Are The Eggs Fertile? ===================== (From a Turtle Homes Member) Eggs from Turtles are fertilized as the eggs are being layed. If the eggs had a mucous feel to them as they were lightly washed by the vet, then maybe they are fertile. Even when I dig up fresh eggs from the ground, as I clean them, if they rinse without any obvious slime on them they will be duds. The slime is the Turtle sperm which actually penetrates the eggs as they exit the Turtle and begin to harden. The tops of the eggs of my eggs turn real white after a day or 2. Again, it is easier to see on paper toweling as mentioned before. Here are your options if you find a turtle nest at a site where you know the nest will get destroyed: 1) Make a chicken wire mesh and put over the nest site, then ignore and see whether turtles will hatch. You can make a wood frame to make it sturdier and keep the dogs and other predators away from eventual hatchlings. If this is in a lawn, don't mow around the nest, and don't walk on the area. 2) Dig up, take indoors, incubate, then let babies go when they are a few weeks or months old. 3) Relocate nest. This is tricky, since turtles eggs should not be turned over once layed. Also, picking a good nest site can be tricky, too. You'd have to take out the nest with quite a bit of dirt, and then "repot" it at the new site. However, if you think this will improve the turtle's chances, why not give it a try. Pick a site that does not soak, drains well, does not completely dry out, gets some sun, and make sure you don't turn over the eggs during digging and transport. 4) Do nothing. This sounds heartless, but only a small number of nests survive predation in the wild, and only a small number of hatchlings survive to adulthood. 5) Instead of incubating the eggs yourself, find someone who would take them. For more information on turtles visit: http://www.soultones.com/turtles.htm http://www.tortoise.org/
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