Bunnies need a high-fibre, low-calorie diet, it prevents obesity. A high-fibre diet helps the teeth to wear down maintaining proper dental occlusion.
Rabbits need a certain amount of calories a day depending on their weight, and 20-25% dietary fibre to maintain gut health. Diets less than 20% fibre result in hypermotility, reduced caecotroph formation, prolonged retention time in the hind gut and enteritis. It has been suggested cecal fermentation produces an amount of volatile fatty acids equivalent to 10-12% of the daily caloric requirement.
What is metabolism?
Metabolism are the chemical reactions in cells that change food into energy.
To maintain daily calorie requirements for your bunny, you need it’s basal metabolic rate (BMR). There are different equations that you can use depending on the body weight of your bunny and it’s health status. If your bunny has been diagnosed by a vet with medical issues, make sure you use the correct equations.
If the adult rabbit is under 2kg
k = kcal constant is 70
W = weight in kg
BMR = kW0.75
Example:
70 * 20.75
70 * 1.68 = 117.7
BMR = 118
Round the result up to the nearest integer. The calculations won’t work well if you use a decimal number.
If the adult rabbit is over 2kg
k = kcal constant is 30 then add 70
W = weight in kg
BMR = 30 * kW + 70
Example:
30 * 3.5 + 70 = 175
BMR = 175
If your bunny is growing (< 6 months old) or elderly
First calculate the BMR of the adult rabbit according to the weight, then
multiply BMR by 3
Example:
70 * 20.75
70 * 1.68 = 117.7
BMR = 118
Some people believe that doubling the BMR is enough, but according to the MSD Veterinary Manual it must be multiplied by 3 for growing bunnies.
If your bunny has diagnosed health issues
First calculate the BMR of the adult rabbit according to the weight, then
multiply BMR by 2
Example:
BMR = 118 * 2 = 236
If your bunny is severely ill
If your bunny has been to the vet and is in really bad shape, for example, if it has been starving or is emaciated you have to decrease the metabolic rate, lowering the calorie requirement.
multiply BMR by 0.7
Example:
BMR = 118 * 0.7 = 83
Warning
Please remember that I am not a vet and the information on this page is taken from various reliable sources:
- MSD Veterinary Manual, Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia
- Food Standards Australia New Zealand, Australian Food Composition Database
If you have questions, don’t hesitate to talk to your vet and do your own research.
Daily calorie intake graph
For those of you who like graphs, here is the recommended daily calorie intake for rabbits depending on their weight.
Metabolic amount
Bunnies get a certain amount of energy from the digestible fibre in their diet. The better the source of nutrients, proteins, fat and carbohydrates they get, the more energy they will have.
You can calculate the amount of energy your bunny needs by finding the basal energy expenditure (BER):
divide BMR by 2
Example:
118 / 2 = 59
BER = 59
