In most cases captive bred animals are avalible for introduction of new blood into any line. But occasionally when we do use wild caught animals as breeders we follow the following rountine:
1. Worm the new animal for internal parasites and treat for external parasites also.
2. Quanrantine the animal for a min. of 90 days away from all other animals.
3. If animal refuses to feed and/or is not a robust captive the quarantine time is extended till they have a solid 90 days of good feeding and good fecals.
4. Then and only then we introduce them into our small room as potencial breeders. Where they are normally maintained for a 6 - 9 month before being moved into the breeding population.
You should note that the above cautions will not prevent the introduction of viruses etc. into your snake collection, but will give you a good indication on the health of the animal. The only sure way to prevent any possibility of introduction of problems would be to run a battery of tests which is normally cost prohibitive.
I am sure that is not what you wanted to hear,but is the best advice I can give. Just a couple of months ago a friend of mine that keeps mainly crotalus introduced a lepidus( motled rock rattler) that was collectted last year and has been being maintained in quarantine since its capture in June of 2003 to one of his captive born lepidus. The animal has been feeding and doing well for nearly a year. The female that was captive born has now developed a pathogen that has knocked her off feed and upon doing some blood work the same pathogen was found present in the wild caught male. Thankfully the pair had been introduced together away from his main collection.
Many times an animal can be a carrier and function perfectly with no probelm but still infect other animals. Any type stimulus such as stress can also kick off a bout of certain problems.
Hope this all helps and sorry I rambled as much as I did.
Bottom line be very careful with coveted captive borns being exposed to any wild caught animal. Also be aware that many breeders such as myself do not allow other keepers into the collection becuase of these type fears.
John Cherry
Cherryville Farms

Cherryville Farms - Reptiles