sexual maturity in the fourth year and assuming an optimistic net harvest 
rate of 50 percent, the yield would be an additional 90 animals. Thus, the 
overall output from our domestic breeding operations would be increasing 
at a rate of 90 per year in the fourth year and incrementally increase 
as these new animals reach sexual maturity. If 14,000 animals are re¬ 
quired per year and the current capacity is 5,500, it would take a total 
of 16 years before any anima'ls could be made available to activities 
other than those legally required, and then only about 1,500 animals. A 
total of 20 years would be required before we could become self-sufficient 
in meeting our total needs for this species. 
Among the breeding programs, there are at least eight general-purpose 
production colonies distributed over a wide geographic area, assuring 
adequate protection against colony disaster. In addition to these 
general-purpose breeding colonies, a number of smaller special-purpose 
breeding colonies have been established. It is estimated these will 
produce approximately 2,000 animals per year. In addition, it is ex¬ 
pected that recycling will result in a net savings of several thousand 
per year. 
Estimated requirements for rhesus 
Anticipated production from 
established general-purpose 
colonies 5,500 
Anticipated special-purpose 
production 2,000 
7,500 
Shortfall to be met by expanded 
general-purpose production, 
recycling, or importation 
14,000 
7,500 
6,500 
Recommendations 
In order to meet the nation's needs, the general-purpose rhesus production 
program should be expanded to a level allowing an annual harvest of 
9,000 animals per year, i.e., an increase of 3,500 over the level of the 
present program. If recycling and importation do not provide the needed 
additional animals, domestic breeding may have to be expanded further. 
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