You haven't told us much useful info about the boas, subspecies, locality and etc. so even an estimation would be impossible.
But I will make this comment (although many people consider this a controversial idea). Boas are individuals and respond best being treated as individuals. And they are very unlike the common colubrids, the successful farming of which is the source for a lot of ideas being appplied to the culture of Boa sp.. There is no exact figure of breeding size or breeding weight in the boas that can be applied across any but the most inbred populations.
These theories of minimum size are based upon observations of closely related animals kept under very similar conditions. And the goals of a keeper that feeds to attain breeding size as quickly as possible may not be the same as every keeper or breeder. My experiences strongly suggest that size, as an indicator of maturity in Boa, is nearly insignificant compared to age.
I believe the results of two programs, one based on size goals and another where age is used as an indicator involving various Boa localities (measured in terms of long-term reproductive success) , would yield plain evidence that the 'feed-to-breed' concept is not the best way to raise and breed the Boa sp.. Although it might be attractive tp persons attempting to beat the market curve with a popular morph.
So I won't be accused of giving my opinions without any real info:
Maturity in imperator is attained at 3 years and at lengths as small as just over 3', with a mass of under 2kg.
The constrictor ssp. takes at least a year longer and at lengths under 5' the females are unlikely to deliver young. Mass in the constrictor is less a factor.
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Gus
A. Rentfro
RioBravoReptiles.com
"Quality is not an accident. Perfectly healthy animals are a minimum requirement.. everything else is just salesmanship" gus
