chicken / grain – calories comparison


I am trying to understand what ratio there is between chicken and grain when it comes to produced calories in the end. So my calculation is not adademic and I am using numbers I found on the web. Please correct me if I am wrong with my preliminary assumption, which is that the grain you need to produce chicken meat could provide 15x the calories that you´ll get from the chicken meat.

Basic assumption, as you can´t eat everything from a chicken, the meat / bones ratio is something around  70:30 meat to bones etc.

Broilers are slaughtered at around 8 weeks

You need about 10.4 kg grain to “produce”  2.8 kg chicken weight less bones *0,7 = 1,96 kg meat result

in lbs: 22,88 lbs grain to 6,14lbs chicken less bones * 0,7 = 4,3 lbs Chicken meat, means you need 5.3 times more grain to produce chichen meat  

1lb (453gramm)  grain has about 1500 kalories

based on above calculation I multiply 1500 kalorien by 22,88 lbs = 34.000 calories

1lb Chicken meat provides about 500 calories = 1 chicken provides about 2145 calories

If my calculation is correct you have to grow grain that could provide 34.000 calories to feed a chicken that in the end provides “only” 2145 calories which is a factor of about 15.

For example, a person that needs 2000 calories a day could either eat a chicken and be happy a bit longer than 1 day or that person could live about 17 days from the grain that would have been used to feed the chicken,

This is just an attempt to calculate the ratio and therefore I am happy if you send your comments, corrections etc.