The differences are nearly identical except on fat content. You have to compare animals of the same size.
An adult mouse is not going to be the same as an adult rat. But a 10 gram mouse is going to be nearly the same as a 10 gram rat.
The only real benefits of feeding rats is that you just have to feed one rat to compared to multiple mice.
It's more of a convenience factor than higher nutritional value.
Nutrient Composition of Whole Vertebrate Prey by RodentPro:
Adult mice (>10g)
- Kcal/g =5.25
- Crude protein % = 55.8
- Crude fat % =23.6
Rats (10-50g)
- kcal/g = 5.55
- Crude protein % = 56.1
- Crude fat % = 27.5
http://www.rodentpro.com/qpage_articles_03.asp
Whole prey according to the USDA(page 14 of their PDF provided below):
Adult mice (>10g)
- Kcalorie/g =5.77
- Crude protein % = 56.9
- Crude fat % = 23.5
Rats (10-50g)
- kcalorie/g = 5.67
- Crude protein % = 60.3
- Crude fat % = 26
http://www.nal.usda.gov/awic/zoo/Who...nal02May29.pdf
Additional data found on a non scientific source:
Adult mice (>10g)
- kcal/g = 5.25
- Crude protein % = 55.8
- Crude fat % = 23.6
Rats (10-50g)
-kcal/g =5.55
- crude protein % =56.1
- crude fat % = 27.5
http://www.leedspetshops.co.uk/nutri...snakes-page-69
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