there are a lot of variables to look at- species, genes, environment, food source, metabolism, on and on. the things you can't control are species and genetics- you've got what you got. what you can control are the food, environment and since metabolism is dependent on the environment of the enclosure, you have some control over that. mader's book "reptile medicine and surgery" as well as rossi's "what's wrong with my snake" both discuss how much to feed your reptile. mader has a standard metabolic rate chart that shows a reptile at 80 degrees needs "x" amount of calories for basic metabolism. since your snake climbs/moves /grows or for a reproducing female, its metabolic requirements would be much higher (more calories). the formula that generally describes how much food your snake needs looks like this:
32 ( a constant) times the mass of the snake in kilograms to the 0.77 power, or for a 50 gram snake (maybe the size of yours?)
32*0.050^0.77
which works out to be 3.18 cal/day for the standard metabolic rate (SMR), just what is needed to live. if you want to grow you need more calories: 1.25*SMR, 1.5*SMR, 2*SMR, whatever.
well that is great. now how many mice are equal to 3.18 calories a day? if you go to rodentpro.com,( you can find them on the main page of KS.com- good product, good prices) and look in their articles section, they have a chart which shows the caloric values for many food items,in calories /gram including rodents. this is a reference, not exact as i have seen other charts with different values. for instance a pinky mouse has 4.8cal/g. but the typical pinky weighs more than 1g, so for a 3g pinky it would have 14.4 cal total.
what i have done in a spreadsheet for all of my snakes is determine their SMR and MR at 1.25*,1.5* and 2*. then i choose the rate of intake for each animal, divided that number by an average value of calories for the food size i anticipate that animal to eat and that will tell you what to feed per day. noone feeds their animals every day so you can multiply it out for every 4,5 or however many days between meals. you will not get a whole number so you will have to round it off. i haven't seen 1.4675 mice yet.
I do this for some reasons- 1) control expense. i have a good size colony for a "hobbyist"; i am not going to cheap out on rodents but i do not want to buy more than i actually have to. i approximated this ( what i have described) with my colony last year without keeping greatly detailed records and got good results with yearling growth and breeders success.
2) i also do it for the animals, and try to keep it as real as possible in this phony environment. it is up to me to decide the rate of feeding and also to observe the animals if even though this is thought out, snake #1 isn't getting enough and is always hungry or snake #9 is getting fat.
to make this work it will help to have a scale in order to weigh out food and to weigh your animals to help you decide when to increase the rate or amount of feeding.
with that said a typical hatchling will be any where between 18" ( from perlowin's AVS softcover "keeping and breeding kingsnakes"
to 40" plus for a powerfed animal after a year.
hope that helps either with your snake or insomnia.
take care
daveB
