All animals of canine species, both male and female.
Any person or persons, firm, association or corporation owning, keeping or harboring a dog as herein defined.
Any dog shall be deemed a public nuisance when attacking persons or domestic animals when such dog is on property other than that of the dog owner; when destroying property; when on a public school grounds and not under restraint; when it persistently chases moving motor vehicles, pedestrians, or bicycle riders; when it persistently and continually barks or howls; when it is permitted to run at large and unrestrained on property other than its owners; any unspayed female dog in season shall be deemed a public nuisance when not confined indoors or housed in a veterinary hospital or registered kennel. Each time one of the above nuisances exists shall constitute a separate offense.