Dear Adejoke, what is your aim? What kind of novelty-induced behaviour would you like to measure? Are you interested in reactions to a novel place or to novel objects that will be introduced into the arena? Thigmotactic behavior is commonly observed in small mammals that in nature can be predated, as rodents, but in dogs it could be less evident.
My experience is with rodents, in which you can study both thigmotaxis and novel object recognition in the arena. For dogs, you could study object recognition memory. Here is a protocol adapted for the dog (the size of the arena was 0.609m x 1.1.5m x 1.08m):
Development of a protocol for studying object recognition memory in the dog, Callahan et al., 2000 (http://www.sciencedirect.com/science/article/pii/S0278584600001020)
If you want to use instead a protocol more similar to the one commonly utilized for novel object recognition in rodents, here you can find a detailed description of the procedure:
Behavioral methods for the study of the Ras-ERK pathway in memory formation and consolidation: passive avoidance and novel object recognition tests, d'Isa, Brambilla and Fasano, 2014 (https://www.ncbi.nlm.nih.gov/pubmed/24470023).