35mm x 45 mm is the specification.I think 34 mm x 45 mm should be ok. They are not going to measure it with a tape.Most of the studio know the requirements.So they take only valid citizenship photo.Hope you went to a good studio and told them the purpose of the photograph.
In my opinion keep only 1 set of photographs.If you have 2 sets check which one is more accurate with the specification and keep that.Other wise it will create confusion or even complication.
Send two identical citizenship photographs.Dont forget to write your name, studio name and date of photograph on back side of both photos.
http://www.cic.gc.ca/english/information/applications/photospecs-cit.asp
