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    COCKER SPANIEL 

    This regal canine was originally bred to be a hunting dog, but they quickly became popular companion pets when they were brought to the United States. The Cocker Spaniel was ranked as the number one breed from 1936 until 1952 when Beagles stole the title. It regained its spot in 1983 through 1990. Since then, the number of registered Cocker Spaniels have decreased. This could be because the breed is susceptible to several heath problems, such as ear infections and hip dysplasia. (National Gun Dog)