G. P. MURPHY 
395 
lung machine has definite and very important 
advantages. Baboon blood groups correspond 
to the human ABO groups. The heart lung ma- 
chine can thus be primed with compatible blood. 
Baboons also tolerate cardiopulmonary bypass 
well. Even lengthy perfusions of up to three 
hours using high flow rates of 100 to 125 ml/ 
min/Kg body weight are followed by prompt 
and complete recovery. During experimental 
mitral valve replacements, no deaths occurred 
during operation in marked contrast to experi- 
ence with mongrel dogs.'^ For cardiac trans- 
plantation, also, the baboon may be as good if 
not better than the mongrel dog.^ Donors and 
recipients of suitable size can be selected for 
blood groups and leukocyte antigen compatibil- 
ity. The whole procedure is easily accomplished 
through a left thoracotomy. The anatomy of the 
baboon heart and the great vessels is closely re- 
lated to that of the human. The anastomoses of 
the atria, aorta and pulmonary arteries present 
no great problem provided adequate lengths of 
the donor preparations are obtained and fine 
suture material is used. The size of the heart 
corresponds closely to the body weight, simpli- 
fying the selection of donor-recipient pairs. 
Heparinization is achieved with doses similar to 
those used in humans and the heparin is effec- 
tively neutralized by Protamine sulphate. The 
bleeding tendency so commonly observed fol- 
lowing cardiopulmonary bypass in dogs, has 
not been encountered in any baboon experi- 
ments.''' 
Bacteriological Aspects 
The majority of this available material is 
based on a comprehensive study in 948 baboons 
previously reported elsewherci i^* 
Bacteriological specimens were taken from 
943 baboons and include specimens of saliva, 
feces, urine, and skin scrapings. Mycobacterium 
tuberculosis was never found. Table III shows 
the incidence of some bacteria in the oral cavity 
of apparently healthy baboons. With the excep- 
tion of five, all these animals were not in captiv- 
ity long. 
The incidence of Staphylococcus aureus and 
proteus species was found to be high. The in- 
cidence of staphylococci was astonishing, since 
it is far higher than that noted in humans 
Tabu) III. — Incidence of Bacterial Species in the 
Oral Cavity of Baboons 
Bacterial Species 
Percentage 
Number 
Staphylococcus aureus haemolyticus 
61.8 
576 
Streptococci, beta-hemolytic 
1.1 
11 
Enterococci 
0.7 
7 
Escherichia coli 
58.3 
550 
Klebsiella pneumoniae 
32.2 
304 
Proteus ._ 
36.4 
343 
Paracolon . 
4.3 
38 
Pseudomonas aeruginosa 
3.3 
31 
Alcaligenes faecalis 
1.0 
9 
(±20 percent) in South Africa. Antibiograms 
were performed on all those isolated. The high- 
est rate of resistance occurred in the novobiocin 
and tetracycline groups. The antibacterial spec- 
trum of novobiocin resembled that of penicillin 
G. Therefore, it was not surprising that most of 
the Gram-negative baboon flora were resistant 
to novobiocin. Tetracyclines are widely used in 
South African agriculture. This may be a select- 
ing factor even in the free-living baboon flora. 
Pathogenic micro-organisms of the fecal flora 
were found. Nineteen percent of all free-living 
baboons were carriers of enteropathogenic types 
of Escherichia coli. The most common types of 
enteropathogenic E. coli were 0 55, 0 119, and 
0 26. The types 0 86, 0 111, and 0 127 occurred 
only sporadically. 
Salmonella sundsvall was isolated from 52 
baboons, not one of which showed signs of 
clinical disease. This type of salmonella seldom 
occurs in human beings in the Cape Province 
of South Africa, but in Canada and Mexico it 
has been described as the cause of gastroenteri- 
tis.^^ These were always sensitive to ampicillin. 
Ampicillin treatment administered preopera- 
tively was, therefore, considered advisable to 
eliminate this latent but potent organism in 
baboons. 
It is well known that monkeys and baboons 
carry shigellae, mostly without clinical signs. 
The incidence observed in our colony is similar 
to that reported in the series of 943 baboons, 
where Shigella flexneri type IV was isolated 
from 43 ; Shigella flexneri type II, from 25 and 
Shigella flexneri type V, from ten.^^ 
Bacteriological findings in gallbladders are 
summarized in Table IV. It shows the difference 
in the incidence of Salmonella sundsvall in this 
flora and the fecal flora. Salmonella sundsvall 
