Vaccine schedule question

[Hawke]

I am a freshman vet student researching a topic for a group immunology 
paper. Our topic is the vaccine Duramune (canine distemper, adenovirus 
type 2, parainfluenza, parvo), and I need to find out about their 
recommended immunization schedule.

According to the insert, their schedule is one dose at 12 weeks, then 
another 2-3 weeks later, and a yearly booster. They also have a schedule 
saying that it should be given at 6 weeks, and again at 8, 10 and 12 
weeks, and a yearly booster.

I am hoping that there is an immunologist on the list, who can answer my 
question (or anybody who knows about this). If you can give the pup a shot 
at 12 and 14 weeks, why give it at 6, 8, 10 and 12? Can a puppy 6 weeks 
old benefit from a vaccination (I don't know at what age a puppy begin 
to produce it's own antibodies). We need to justify the schedule 
recommended by the manufacturer.

Thank you,
Sharon Hartshorn
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Sharon Hartshorn                                 sharonh at holly.colostate.edu
DVM CLASS of 2000  	                  	   hawke at lamar.colostate.edu
Colorado State University                  http://lamar.colostate.edu/~hawke
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 "However, William Harvey was so impressed by the complexity of blood flow
 that he thought initially the motions of the heart and the blood could be
    comprehended only by God. Generations of veterinary students since
    Harvey's time have tended to agree with his assesment." - From the
            Textbook of Veterinary Physiology by Cunningham
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