How many crix and how often?
For adults, a dozen gut loaded crickets 2-3 times a week, salad every day.
How often should she 'go potty'?
Typically once a day though it's not unusual for them to skip a few days. Make sure greens are freshly washed or misted if pre-washed, to ensure adequite moisture is eaten with the salad. If in doubt or she hasn't gone in more than three days, a 10-20 soak in luke warm water (about 80F) typically helps them to go. Some grated or pureed carrots, squash or sweet potato added into the greens a few times a week helps as well.
Can you make them exercise?
Taking the bearded dragon out of the tank to explore, supervised in a beardie safe area of the room (someplace where they can't get into trouble with house plants (some are poisonous to dragons if they nibble on them) power outlets, stairs, under doors etc, away from other pets (ie cats, dogs, larger snakes or lizards that are loose). You can also buy or make a beardie harness to put on your dragon when taking them outside(weather permitting of course) or a large screen cage or rubbermaid container with a shaded spot can be used to give them explosure to natural sunlight.
Her eyes and mouth are clear... could she have another issue? Or is she slowing down with age (or for the winter)?
Dragons typical do brumate around this time, but it's always best to stop feeding a couple days before they brumate. Before assuming she is slowing down for the winter, make sure her fecals are clear and she is otherwise healthy. Rapid weight loss is a sign of ill health. If you havent' had her for very long, she could just be still going through the process of getting used to her new home and owner.
As for the possibility of being gravid, it is always possible. Females can and do lay eggs when they have never been in contact with a male all their lives. Signs of being gravid is usually an increase of eating, unless they are close to laying, usualy 24-48 hours before laying eggs, they will stop eating. Extensive digging will also be observed, as the female tries to look for a suitable egg laying site. If she is trying to dig for egg laying spots, you will need to prepare an egg laying bin for her. A rubbermaid container about 24"x16"x14" in dimentions (lxwxd) or something around the size is good. Put in a foot or more of vermiculate/untreated potting soil, add water so it clumps together nicely when squeezed but no water drips out. You can either put this bin right into th eir cage (make sure there is a ramp for easy access, both in and out, or put the dragon in the bin itself. Most dragons, if th ey are close to laying will proceed to dig holes, then once they are satisfied with the hole they made she will lay eggs. Once she is done, give her a warm bath to clean her and put her back into her cage to bask. Offer food a bit later. Laying eggs is exhausting.
The eggs themselves, you can freeze over night then toss, if you are 100% sure she has never been in contact with a male. The freezing is just to make sure the eggs are not viable, as you don't want them to hatch in some garbage dump and die from exposure or predators.
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PHLdyPayne