Ch. 1— Summary, Policy Issues, and Options for Congressional Action • 5 
sometimes be identified and quantified by observ- 
ing an animal’s behavior. Pain is relieved with 
analgesics or anesthetics; distress is eased with 
tranquilizers. Widely accepted ethical standards 
require that scientists subject animals to as little 
pain or distress as is necessary to accomplish the 
objectives of procedures. Professional ethics re- 
quire scientists to provide relief to animals in pain 
or distress, unless administering relief would inter- 
fere with the objective of the procedure (e.g., when 
the objective is a better understanding of the mech- 
anisms of pain). 
HOW MANY ANIMALS ARE USED? 
Estimates of the animals used in the United States 
each year range from 10 million to upwards of 
100 million. OTA scrutinized a variety of surveys 
(see ch. 3), including those of the National Research 
Council’s Institute for Laboratory Animal Resources 
and the Animal and Plant Health Inspection Serv- 
ice (APHIS) of the U.S. Department of Agriculture 
(USDA). Indirect estimates of animal use were also 
based on data such as Federal funds spent on ani- 
mal research and sales revenues of the Nation’s 
largest commercial breeder of laboratory animals. 
All these data are unreliable. No data source ex- 
ists, for example, to enumerate how many institu- 
tions do not report animal use. In addition, non- 
reporting institutions may not be similar enough 
to reporting institutions to justify extrapolation. 
Thus every estimate of animal use stands as a rough 
approximation. With this caveat in mind, the best 
data source available — the USDA/ APHIS census 
— suggests that at least 1 7 million to 22 million 
animals were used in research and testing in 
the United States in 1983. The majority of ani- 
mals used— between 12 million and 15 million— 
were rats and mice. Current data permit no state- 
ment about any trends in animal use through re- 
cent years. Animal use in medical and veterinary 
education amounted to at least 53,000 animals in 
the school year 1983-84. 
The Animal Welfare Act of 1966 (Public Law 89- 
544), as amended and presently enforced, requires 
research and testing facilities to report to USDA 
their annual use of dogs, cats, hamsters, rabbits, 
guinea pigs, and nonhuman primates (see ch. 13). 
(About two-thirds of the reporting institutions also 
volunteer the number of rats and mice used.) For 
fiscal year 1983, the USDA reporting forms indicate 
the facilities used nearly 1.8 million of these six 
kinds of animals (see table 1-1). 
Table 1-1.— Animal Use Reported to the 
U.S. Department of Agriculture, 1983 a 
Number used 
Animal in 1983 
Dogs 182,425 
Cats 55,346 
Hamsters 454,479 
Rabbits 509,052 
Guinea pigs 521,237 
Nonhuman primates 59,336 
Total 1,781,875 
a Totals do not include rats or mice, two species that together represent the 
majority of animals used. 
SOURCE: Office of Technology Assessment. 
USDA reports are of limited utility because: 
• the Department counts only six kinds of ani- 
mals that together account for an estimated 
10 percent of the total animals used (report- 
ing of rats, mice, birds, and fish is not re- 
quired); 
• the annual summary report does not tabulate 
reports received after December 31st of each 
year, resulting in a 10- to 20-percent underes- 
timation of laboratory use of regulated species; 
• ambiguities in the reporting form ask respond- 
ents to add figures in a way that can cause 
animals to be counted twice; and 
• terms on the reporting form are undefined 
(e.g., the form has room for voluntary infor- 
mation about “wild animals,” but does not 
specify what animals might be included). 
In the absence of a comprehensive animal census, 
the USDA reports will continue to provide the best 
data. Imprecise as they are, these reports can iden- 
tify major changes in the numbers of dogs, cats, 
hamsters, rabbits, guinea pigs, and nonhuman pri- . 
mates. (It is important to note that any change in 
the total number of animals used may reflect not 
only the adoption of alternative methods, hut 
changes in research and testing budgets as well.) 
