I think a stout stick is a better defence than a knife. This is more visible than a knife to any creature that is threatening you and might make them reconsider when they are at a safe distance. Also you can carry a stick when hiking without making other people nervous.
A few days ago I was doing some jungle trekking in Malaysia. I was conscious of the slim possibility of encountering a tiger, panther or bear, however the only animals that threatened me were a group of stray dogs when I was walking in a backstreet of the nearby town. Luckily a guy on a motorbike saw my predicament and chased them off. This is not the first time I have been threatened by dogs in Asia. The locals walk amongst the stray dogs all the time and seem to be ignored. I believe dogs are more likely to threaten a person who looks different to the humans they are used to. I know my daughter is often embarrassed when her dog barks and growls at black people she encounters when out walking.