Officials at the American Humane Association's Animal Welfare Research Institute said 3 million to 4 million healthy, adoptable pets are euthanized at shelters each year, and to better understand pet ownership and retention, the group developed a study.
Of the more than 117 million U.S. households, 46.3 million had a dog and 38.9 million had a cat, the officials said.
The first phase of the study -- a survey of 1,500 former pet owners and non-pet owners -- found there were multiple barriers for having a pet including the cost, the lack of time to care for a pet, dislike of companion animals and the lasting grief from the death of a previous pet.
In spite of the widely discussed research on the physical and emotional benefits of pet ownership for older people, U.S. seniors citizens were the least likely to consider a pet.
Six-in-10 former dog owners age 65 and older would not consider getting another dog, and 66 percent of former cat owners would not consider another cat. Of those who had never owned an animal, 90 percent of seniors said they would not consider getting a dog and 94 percent said they were not open to owning a cat.
The survey of 1,500 U.S. adults was conducted in February has a margin of error of 4.4 percentage points.
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