Rat BMI Survey

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Rat BMI Survey

Post by Jemma » Mon Feb 01, 2010 8:08 am

I thought this might be an interesting one to do, as owners I’m sure we spend a good portion of time worrying if our rats are overweight, weight on it’s own isn’t a good guide as a rat can both be too fat and too thin at the same weight depending on it’s size. I was wondering if there was a range, like with humans BMI, that could give us an idea of what was about right. The possible measurements I could think of was Weight divided by Length, Neck circumference and Chest circumference to give us 3 possible ‘indexes’. I’ve measured my 4 lads to start things off which gives me the following below.

Loki (11m old Buck)
Body Length: 27.5 cm
Neck: 14.5 cm
Chest: 19.8 cm
Weight: 655 g
Body Length Index: 23.8
Neck Index: 45.2
Chest Index: 33
Notes Index: Big butch buck, slightly soft rat, probably not overweight with it, just needs tone

Mu (10m old Buck)
Body Length: 26.5 cm
Neck: 14 cm
Chest: 18.5 cm
Weight: 562 g
Body Length Index: 24.7
Neck Index: 46.8
Chest Index: 35.4
Notes Index: Nicely proportioned rat, about spot on

Yoshi (10m old Buck)
Body Length: 24.5 cm
Neck: 13.2 cm
Chest: 20 cm
Weight: 552 g
Body Length Index: 26.7
Neck Index: 49.6
Chest Index: 32.8
Notes Index: Compact stocky lad, not overweight but solid

Odin (11m old Buck)
Body Length: 28.6 cm
Neck: 13.8 cm
Chest: 18 cm
Weight: 546 g
Body Length Index: 22.9
Neck Index: 47.5
Chest Index: 36.4
Notes Index: Long relatively skinny rat, verging on underweight

I would appreciate it if anyone with the inclination gave it a go themselves and popped the results on here, if your not sure about working out the indexes then pop on the measurements and I’ll work it out for you. If you have a lot of rats and not much time a range of different body shapes would be great. If you could include notes on your perception of there shape/weight as well it would be very useful. Some measuring tips;

Length – Use a bit of string or ribbon, hold the end at the base of the rats tail and measure up to the tip of the nose, try and make sure the rat is fully extended or stretching, bribery with a treat can help. Measure the length of the string once complete

Neck – loop the string/ribbon around the neck (try and make sure the rat isn’t tense at the time) making sure it’s snug but not tight and measure the length of the ribbon.

Chest – measure the chest from immediately behind the front legs, as with the neck

Weight – If your rats will sit in the kitchen scales then that’s ideal, if not get a carrier and zero the scales with it on empty, then add the rat and weight until the numbers roughly settle down.

Measurements wise all lengths should ideally be in cm’s and all weights in grams, if your not sure then let me know what unit you’ve used and I will convert.
Muse rattery
North of England Rat Society - next show Preston 25th June

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Posts: 7587
Joined: Tue May 04, 2004 6:04 pm
Location: Cheltenham

Re: Rat BMI Survey

Post by aquajen9 » Mon Feb 01, 2010 8:43 pm

Bearing in mind how inaccurate BMI can be for humans.. i'm not sure a rat one would be any more accurate.. plus - I have had hundreds of rats over the years who have all been similarly sized, but totally different in structure, and rats from pet shops who are lightweight but the same size as breeder rats, who weigh twice as much...
Jenna and the rats of Hakuna Matata
Hakuna Matata Rattery Breeding for Black Eyed and Ruby Eyed Siamese, Russian Blue and Black. Some Dumbo and Rex.. Agouti Variegated and Topaz Variegated.


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