I highly doubt that you feed a weaned rat to a 104 grams BP and small even less likely so not knowing what you really feed it's hard to tell whether or not you feed the right size.
What you need to feed is a prey equal you animal's girth size one a week that is more than enough and do so until the animal is about 500 grams.
Because a snake is 104 grams at 4 months does not mean anything, it could be an animal that was very small out of the egg and took a few weeks to get started. People put too much faith in number and not enough in overall body shape.
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