I agree with everything Anthony said below and would just like to add that when comparing two boas, one male and one female, of exactly equal length, the female will be the more robust of the two. Males are generally leaner.
Additionally, of the larger constrictors, boas are fairly trim and should have a "bread loaf" look to them. The healthiest boas will have a lines running from head to tail down their dorsum along their spine and lines running the length of their bodies on their laterals as well. Those lines are the muscles protruding. This is an EXCELLENT sign of a boa with good body composition (minimal fat, lots of muscle). Inch for inch, boas are the strongest of the constrictors and a healthy specimen should show it.
jb
>>I think your boa is a perfect size for a male at 2 years of age.
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>>Ask yourself if you want a small or large adult boa first.
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>>If you want a small boa (4-5 feet), then I'd recommend feeding him one food item every 3 weeks, and I would never offer anything larger than a medium rat.
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>>It you'd like a large boa, then you might try feeding him one food item every two weeks that leaves a little bulge in him. Depending on how he grows, you may be able to feed him rabbits in his older years.
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>>Males typically stay smaller than females, but I have had males that were 19 pounds and could easily eat a small rabbit.
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>>Large boas are not my personal preference. I only feed my big girls one jumbo rat every 2 weeks, and they stay around 7 feet long and between 15-20 pounds.
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>>Best of luck with him. I hope this helped.
>>
>>-Anthony
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What's written above is purely my opinion. In fact, MOST of what you read on the internet is someone's opinion. Don't take it too seriously 
Jonathan Brady
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