BTS are truly omnivores and so they require a wide range of foods to thrive in captivity. That being said, they do not need a lot of fat in their diet. Thus, cat food is not recommended as it is generally high in fat. Senior dog food is at least better as the fat content is usually lower. But why mess around with canned crap when you can provide much healthier and fresher foods?
I don't know what the contents are in canned monitor food, so I can't comment on it. Look at the ingredients and dietary breakdown if it's on the can.
Cooked and chopped chicken has always worked very well for me. Mix in some veggies and fruits and you have a well-balanced and tasty dish for your BTS.
But above all, do not feed the same things week after week. As omnivores, BTS can be fed an almost-endless variety of foods: chicken, roaches, crickets, apples, snails, greens, tomatoes, grapes, berries, worms, melons, liver, etc. They may not like all of these but most will. And most will prefer meats so it is important to cut up the meat and mix in the non-meat foods.
And before anybody boo-hoos about mixing in grapes and chopped liver -- these are skinks we're talking about, not finicky humans.
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Edward
Carpe diem