Players are always asking me what is the best DNA sample for each sample type?  That is a hard question!  It really depends on what you are going to use the BIO PET for?  Here are the 4 types of DNA you will need to make a bio pet.  You will need to search the world and use your "animal lore" skill to view the stats of each monster/pet and determine whch one will give you the best results.

Prowess This type of DNA deals with power. It determines the amount of Str, Hits, Damage, Physical Resistance and Fighting Skills a creature has.

Environment This type of DNA deals with resists and speed. It determines the amount of Dex, Stam, Fire resists, Cold resist and Poisoning Skill.

Mental This type of DNA deals with magic and mind power. It determines the amount of Int, Mana, Energy & Poison Resists and Magic skills.

Mimic This type of DNA deals with power moves and looks of the creature. It determines the body form, sound and power moves & counter attacks. Some rare samples can contain a power move and a counter attack in one sample of DNA.

FYI Luck plays a large role in successfully gathering DNA from creatures.

If any players have some exact information on the best DNA to use, and want to share...please post it here!  

Bio Engineering - UOEvolution Wiki