Macaca mulatta (Rhesus Monkey) 
Utilization 
This macaque has always been considered the general purpose primate for 
experimental purposes. It is also by far the most widely used primate 
for the production and testing of biological products. Large numbers 
are used for safety testing of poliomyelitis and other vaccines. As a 
result of a long history of its use and the data that has been developed 
with respect to the anatomy, physiology, and behavior of this animal, it 
is highly preferred for many experimental purposes. Restrictions of 
supplies within the past few years have led to substitutions of other 
primates, especially Macaca fasclcularis . 
Foreign Sources 
Geographically, the rhesus monkey is found within India and neighboring 
countries. The number available has dropped considerably in recent 
years. In 1972, an estimated 50,000 of these animals were exported from 
India, the primary source country. In 1974, the Government of India 
authorized a worldwide export of 30,000, approximately 20,000 of which 
were received in the United States. In 1975, and 1977, the Indian export 
quota was 20,000 rhesus per year worldwide, of which approximately 12,000 
per year came to the United States. Very small numbers of these monkeys 
were occasionally exported from Bangladesh during that period. 
Late in 1977, the Indian government announced a ban on all exports of 
primates, which became effective April 1, 1978. Although there remains 
the possibility of obtaining rhesus from other countries of southern 
Asia, the wild populations are relatively small and, even at best, would 
allow the withdrawal of limited numbers of animals. 
Production in United States 
After making allowance for some animals as replacement breeding stock, 
the present breeding colonies of rhesus in the United States should 
yield a net of 5,500 annually by 1980. Nearly all of this production is 
federally supported. The pharmaceutical industry has recently initiated 
a rhesus breeding project to meet needs for vaccine testing, but is 
unable to carry out its plans for lack of breeding stock. 
Currently the 5,500 would meet less than 50 percent of our overall needs 
and, with no imports available, would have to be assigned first to meet 100 
percent of the needs requirements for legally required vaccine testing. In 
this situation, some progeny must be diverted to expand breeding colonies, 
a process which will take several years. With no new animals coming 
into the "pool" of the 5,500 produced each year, as many as 2,730 males 
and 2,570 females could go to vaccine testing. The remaining 180 females 
and 20 males would be used to expand breeding programs. After reaching 
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