The History of Pound Seizure and Related State Laws
The use of animals from pounds and shelters in laboratories has been a controversial issue in the animal advocacy and research communities since the late 1800s. After World War II, as the use of animals in research began to boom and the biomedical research community acquired more power, laboratories and schools began to scramble to obtain animals to use as research, testing, and teaching subjects. Scientists turned first to pounds and shelters, which were places full of 'surplus' animals who could be acquired cheaply. The argument was made, and continues to be made today, that these animals are unwanted and are going to be euthanized anyway. Therefore, in the scientists' minds, their use in biomedical research was not only justified, but was also essential for the progress of modern medicine and increasing commercialization of pharmaceuticals, cosmetics, household products, etc.
Beginning in the 1940s, laws were passed that required pounds and shelters to release dogs and cats to research laboratories. The majority of laws regarding animals in laboratories passed between 1945 and 1960 were generated by the National Society for Medical Research, which eventually evolved into the National Association for Biomedical Research (NABR).

Minnesota, Wisconsin, and New York were among the first states that enacted laws requiring the release of animals in shelters or pounds to dealers. Though these laws were enacted in the 1940s and 1950s, some of them still exist today. Others have been repealed or amended, as a result of demands of the animal protection community.

You can look up the laws on pound seizure for your own state.

In 1965, New York Congressman Joseph Y. Resnick introduced a federal bill in response to the story of Pepper, a Dalmatian who was stolen, sold to a research facility, and killed. This incident, along with a 1966 Life Magazine exposé entitled "Concentration Camps for Dogs," played an important role in the creation of the 1966 Laboratory Animal Welfare Act, now known as the Animal Welfare Act (AWA). This was the first piece of federal legislation in the U.S. that established humane standards for the care, transport, and acquisition of animals used in laboratories, and it also required the regulation of dealers who sold animals to research institutions. In 1990, the Act was amended to define a minimum holding period (five days) for animals in shelters or pounds who are to be sold to research facilities. It specifies that this time will allow their 'owner' to claim them or give them an opportunity to be adopted. The amendment also established record keeping requirements for dealers who obtain companion animals from these sources.

Three states still require pound seizure of publicly–funded shelters and pounds—Minnesota, Oklahoma, and Utah.

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