Where did the current one time per weeks at 10% to 15% prey weight to snake weight come from? Any scientific data?
Before anyone answers, research was done on other more active species. What was determined was that adult females roughly (190 grams) of this more active species with a quicker metabolism needed 25 to 30 rodents yearly to be able to produce viable, large clutches.
For males of the same species, it was determined that 14 rodents would be required to sustain it's normal activity through the year.
The study was based on 190 gram snakes (average) and 30 gram prey items (roughly 16% snake to prey weight ratio per meal).
However if you calculate the TOTAL number of meals, a breeding female needed 900 grams of food over the course of a year and a male needed 420 grams of food.
In order to compare apples to apples, the weekly caloric requirement breaks down as such:
Females = 17 grams per week.
Males = 8 grams per week.
Which means that the % of snake to prey weight ratio for an active south american snake with a high metabolism is 8% for breeding females and 4% for males.
Now keep in mind that these snakes are not equally active throughout the year - meaning that the females ingest the main portion of their caloric intake over a six month period. Males slightly longer. Still, if we apply it to captive animals which (except for rare instances) are kept in enclosures that do not permit the same level of energy expenditure, we could argue that the caloric requirements are less than the 8%/4% indicated by studies.
So....
Where do we get the 10% to 15% of body weight recommendations for ball pythons? They are fairly inactive snakes with slow metabolisms that are prone to captive obesity...can anybody back up this number? Furthermore, this caloric recommendation is not dependent on sex or reproductive status...or is it?
Again, studies have been done on other species - species which are more active and have faster metabolisms. Metabolisms which are maybe 50% efficient.....
...and those studies show that these species need less calories by percentage of prey size than is currently being recommended for ball pythons.
First things first - where did the 10% to 15"% number come from? Anybody?
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