Abstract
Comprehensive health information and baseline data on free-ranging animals is necessary to evaluate the impacts of habitat destruction, reintroduction and translocation programs.2 Taking advantage of ongoing translocation efforts to rescue wild orangutans in Malaysia, a health evaluation was conducted on these primates. Between August 1996 and August 1997, 56 wild orangutans were captured and translocated to protected habitat by the Sabah Wildlife Department.4 These animals underwent a complete physical examination and blood, hair and fecal samples were collected. The test panels run on blood samples included hematology, serum chemistry, toxicology, metals, minerals, vitamins and examination for infectious diseases (the latter including the evaluation for viral, parasitic, fungal and bacterial diseases).
The preliminary results in this field report provide, for the first time, critically needed 1) baseline information on free-ranging orangutans, 2) references for comparison in case of future disease outbreaks, and 3) data for the development of rational protocols to guide existing and developing rehabilitation and release programs.
Basic hematology, serum chemistry, vitamins and serum-soluble elements results are presented in Tables 1, 2, 3 and 4, respectively. Positive antibody titers for leptospirosis, flavivirus, alphavirus (arbovirus), rotavirus, adenovirus and respiratory syncytial virus were found in the wild orangutans (Table 5). These pathogens have the potential to affect wildlife population dynamics as well as the local human and livestock population. The prevalence of potential active mycobacterial infections, based on serum Ag85 levels, was low in the free-ranging population.3 Plasmodium pitheci was seen in <25% of all wild orangutans evaluated based on peripheral blood films and a nested-PCR technique with high sensitivity for Plasmodium species.1,5 No confirmed cases of Plasmodium sylvaticum have been identified in the wild animals sampled. Chlorinated pesticides (aldrin; alpha-BHC; beta-BHC; O,P’-DDD; P,P’DDD; P,P’-DDE; O,P’-DDT; P,P’-DDT; dieldrin; endrin; heptachlor; heptachlor epoxide; lindane (gamma-BHC); and nonachlor) and PCBs were not detected in samples analyzed. Samples analyzed for microfilarial infections were also negative. Further laboratory work is underway and, when completed, the results will be analyzed as they relate to sex or age classes, vector- and nonvector-borne diseases. Determining the significance of the negative and positive titers and the potential pathogenicity of these agents is imperative. Identifying critical health factors affecting wildlife populations is the first step to understanding the role of diseases in population dynamics.2 This knowledge is essential for conservation management decisions. This study provides this information and will spur further research.
Table 1. Hematology values for free-ranging orangutans
|
|
Mean (±SD)
|
Range
|
|
PCV (%) (n=46)
|
32.7 (±5.2)
|
22–46
|
|
TS (g/dl) (n=46)
|
6.8 (±0.58)
|
5.2–8
|
|
WBC (×103/µl)
|
9.680 (±1.817)
|
7.7–12.5
|
Table 2. Serum chemistry values for free-ranging orangutans
|
Test (n=38)
|
Units
|
Mean
|
SD
|
Test
|
Units
|
Mean
|
SD
|
|
GLUC
|
mg/dl
|
118.7
|
47.5
|
K
|
mEq/L
|
4.55
|
1.12
|
|
BUN
|
mg/dl
|
10.8
|
13.4
|
Cl
|
mEq/L
|
97.5
|
15.4
|
|
CREAT
|
mg/dl
|
1.4
|
2.2
|
A/G
|
Ratio
|
1.56
|
.33
|
|
TP
|
g/dl
|
6.75
|
0.63
|
BUN/CRT
|
Ratio
|
9.48
|
7.7
|
|
ALB
|
g/dl
|
4.07
|
0.55
|
GLOB
|
g/dl
|
2.6
|
0.42
|
|
BILI
|
mg/dl
|
0.57
|
0.54
|
CO2
|
mEq/L
|
5.2
|
1.67
|
|
ALK PHOS
|
U/L
|
288.9
|
186.3
|
LIP
|
U/L
|
23.2
|
22.4
|
|
ALT
|
U/L
|
65.9
|
88.8
|
AMYL
|
U/L
|
187
|
565
|
|
AST
|
U/L
|
246
|
490
|
TRIGLYC
|
mg/dl
|
71.2
|
30.4
|
|
LDH
|
U/L
|
1424.8
|
2508
|
CPK
|
U/L
|
2497
|
3767
|
|
CHOL
|
mg/dl
|
161.9
|
165.9
|
GGTP
|
U/L
|
14.7
|
10.6
|
|
Ca
|
mg/dl
|
8.46
|
1.32
|
Mg
|
mEq/L
|
1.63
|
0.41
|
|
PHOS
|
mg/dl
|
3.68
|
1.2
|
|
|
|
|
|
Na
|
mEq/L
|
135.5
|
17.7
|
|
|
|
|
Table 3. Vitamin levels in free-ranging orangutans (in µg/ml)
|
Vitamin (n=38)
|
Mean
|
SD
|
Range
|
|
Alpha-tocopherol
|
2.1
|
±1
|
0.7–4.88
|
|
Retinol
|
0.41
|
±0.18
|
0.16–0.87
|
|
Gamma-tocopherol
|
0.27
|
±0.12
|
0.1–0.55
|
Table 4. Serum soluble element values in free-ranging orangutans (in ppm) (n=33)
|
Mineral
|
Mean
|
±SD
|
Range
|
Mineral
|
Mean
|
±SD
|
Range
|
|
Ba
|
0.07
|
0.01
|
0.05–0.132
|
Cr
|
0.27
|
0.03
|
0.22–0.33
|
|
Fe
|
2.08
|
1.0
|
0.547–4.76
|
Cu
|
2.09
|
0.44
|
1.48–3.37
|
|
P
|
126.8
|
27.56
|
73.2–195
|
Mn
|
0.086
|
0.096
|
0.056–0.62
|
|
B
|
1.38
|
0.16
|
1.11–1.67
|
Na
|
3539
|
198
|
3200–4300
|
|
Ca
|
99.2
|
8.18
|
88–125
|
Co
|
0.14
|
0.01
|
0.11–0.16
|
|
Mg
|
24
|
6.9
|
10.1–44.5
|
Mo
|
0.28
|
0.03
|
0.22–0.33
|
|
Zn
|
1.23
|
0.37
|
0.5 2.0
|
K
|
190
|
37.7
|
142–2
|
Acknowledgments
The authors thank the Sepilok translocation team, especially Elis Tambing for his hard work in catching wild orangutans; Richard Heberling at the Primate Virus Reference Lab for sample analysis; Mark Eberhart at the Center for Disease Control for vector-borne disease analysis; Renke and Pamela Thye for their support; and the Morris Animal Foundation for supporting laboratory analyses.
Literature Cited
1. Cox-Singh, J., S. Mahayet, M. S. Abdullah, and B. Singh. 1998. Increased sensitivity of malaria detection by nested polymerase chain reaction using simple sampling and DNA extraction. International Journal of Parasitology. In press.
2. Karesh, W. B., and Cook, R. A. 1995. Applications of veterinary medicine to in situ conservation efforts. Oryx. 29: 244–252.
3. Kilbourn, A. M., H. P. Godfrey, R. A. Cook, P. P. Calle, E. J. Bosi, S. I. Bentley-Hibert, M. Andau, and W. B. Karesh. 1998. Serum antigen (Ag85) levels in adjunct testing for active mycobacterial infections in orangutans (Pongo pygmaeus). 1998 Keystone Symposia. In press.
4. Kilbourn, A.M., E. J. Bosi, W. B. Karesh, M. Andau, and E. Tambing. 1997. Translocation of wild orangutans (Pongo pygmaeus pygmaeus) in Sabah, Malaysia. Abstract. In: 1997 Proceedings American Association of Zoo Veterinarians.
5. Singh, B., J. Cox-Singh, A. O. Miller, M. S. Abdullah, G. Snounou, and H. A. Raham. 1996. Detection of malaria in Malaysia by nested polymerase chain reaction amplification of dried blood spot on filter papers. Transaction of the Royal Society of Tropical Medicine and Hygiene. 90, 519–521.