Pathogenesis of hemosiderosis in lemurs: Role of dietary iron,tannin, and ascorbic acid

Clinical disease associated with excess iron deposition (hemosiderosis) in the duodenum, liver, and spleen occurs in captive lemurs. In this report we review the occurrence of hemosiderosis and related disease in the Zoological Society of San Diego lemur collection; we then define and describe potential pathogenic factors with the goal of establishing rational husbandry methods to limit or prevent the disease. At the San Diego Zoo, all 49 lemurs necropsied since 1968 were hemosiderotic, the severity increasing with increasing age; liver and kidney disease were common. Our review of iron metabolism, current knowledge on the pathogenesis of hemosiderosis in humans, and the diets of captive and wild lemurs reveals several key dietary substances that may contribute to lemur hemosiderosis: iron, tannins, and ascorbic acid. In captivity, excess dietary iron (commercial monkey chow) and high levels of ascorbic acid (citrus fruits) lead to enhanced iron uptake and increased toxicity of stored iron due to free radical formation. In the wild, lemurs have an unusual preference for leaves, fruits, and bark high in tannin, a polyphenolic secondary plant compound that rapidly chelates iron, protein, and minerals in the gastrointestinal (GI) tract, preventing their absorption. These findings suggest that hemosiderosis in captive lemurs results from a diet high in iron, high in ascorbic acid, and lacking in tannin. Immediate correction of captive diets may limit hemosiderosis in lemurs in the future.     

Hematology and serum chemistry values of juvenile and adult ruffed lemurs (Varecia variegata)

Hematologic and serum chemistry values are presented for adult and juvenile red ruffed lemurs (Varecia variegata rubra) and black and white ruffed lemurs (Varecia variegata variegata) maintained in a zoological collection. Hematologic and serum chemical values are compared between age groups and subspecies and with other primate species. Elevated hematocrit, total protein, and serum albumin values were noted. Significant differences in cholesterol, total protein, and serum albumin values between the two age groups are discussed.     

Lipoprotein particles from the Golgi apparatus of guinea-pig liver

1. A cell fraction has been isolated from guinea-pig liver and shown to be rich in Golgi apparatus by electron microscopy. The activity of UDP-d-galactose-N-acetylglucosamine galactosyltransferase was over 100-fold greater in this cell fraction than in the liver homogenate. These data support the conclusion that the fraction was enriched in Golgi apparatus. 2. The Golgi cisternae and secretory vesicles contained electron-dense particles of 10-80nm diameter. Disruption of the Golgi apparatus cell fraction released these particles, which were separated into VLD (very-low-density) and LD (low-density) species on the basis of their density. 3. The Golgi VLD particles possessed morphological, flotational, chemical and immunochemical properties which closely resembled those of the serum VLD lipoproteins from the same animals. 4. The Golgi LD particles were rich in phospholipid, containing 48.1% by weight. The chemical composition of these particles was quite distinct from that of the serum LD lipoproteins, but did, however, show some similarity to that of the serum VLD lipoproteins. A marked resemblance was noted in the chemical characteristics of the Golgi LD and VLD particles (with the exception of triglyceride content). In addition, these two species of Golgi particles possessed the same antigenic determinant. 5. The results suggest that the Golgi VLD particles are the precursors of the serum VLD lipoproteins. On the basis of similarities in gross chemical composition and in the antigenic determinant of the Golgi LD and VLD particles, we conclude that the LD particles are probably the precursors of the VLD particles. In view of the marked differences in gross chemical composition of the Golgi LD particles and serum LD lipoproteins, it appears unlikely that the LD particles are directly secreted into the serum pool.     

Evidence for supercoiled hepatitis B virus DNA in chimpanzee liver and serum Dane particles: possible implications in persistent HBV infection

In chimpanzee hepatitis B virus (HBV) carriers, the mechanism of viral persistence has been examined by analyzing viral DNA molecules in liver and serum. Chimpanzee liver DNA contained two extrachromosomal HBV DNA molecules migrating on hybridization blots at 4.0 kb and 2.3 kb. There was no evidence for integration of HBV DNA into the host genome. The extrachromosomal molecules were distinct from Dane particle DNA and were converted to linear 3.25 kb full-length double-stranded HBV DNA on digestion with Eco RI. Nucleases S1 and Bal 31 converted "2.3 kb" HBV DNA to 3.25 kb via an intermediate of "4.0 kb" apparent length. The HBV DNA molecule that migrated at 2.3 kb represents a supercoiled form I of the HBV genome, and the molecule that migrated at 4.0 kb represents a full-length "nicked," relaxed circular form II. Evidence for supercoiled HBV DNA in serum Dane particles was obtained by production of form II molecules upon digestion with nuclease S1 or Bal 31. It is proposed that most Dane particles represent interfering noninfectious virus containing partially double-stranded DNA circles and that particles containing supercoiled HBV DNA may represent infectious hepatitis B virus.     

Visualization of TT virus particles recovered from the sera and feces of infected humans

TT virus (TTV) has not yet been cultured or visualized. We attempted to recover and visualize TTV-associated particles from the serum samples and feces of infected humans. Serum samples were obtained from 7 human immunodeficiency virus (HIV)-infected patients. Three patients had a high TTV DNA titer (10(8) copies/ml), three had a low TTV DNA titer (10(2) copies/ml), and one was negative for TTV DNA. Fecal supernatant was obtained from a different TTV-infected subject. The serum samples were fractionated by high-performance liquid chromatography, and TTV DNA-rich fractions were subjected to floatation ultracentrifugation in cesium chloride. Virus-like particles, 30-32 nm in diameter, were found in the 1.31-1.33 g/cm(3) fractions from each of the three serum samples with high TTV DNA titer, but not in any fraction from the four serum samples that either were negative for TTV DNA or had low TTV DNA titer. The TTV particles formed aggregates of various sizes, and immunogold electron microscopy showed that they were bound to human immunoglobulin G. Similar virus-like particles with a diameter of 30-32 nm banding at 1.34-1.35 g/cm(3) were visualized in fecal supernatant with TTV genotype 1a by immune electron microscopy using human plasma containing TTV genotype 1a-specific antibody.     

A novel cell line (Caco-2) for the study of intestinal lipoprotein synthesis

Lipoprotein synthesis by the colonic adenocarcinoma cell line Caco-2 was investigated to assess the utility of this cell line as a model for the in vitro study of human intestinal lipid metabolism. Electron micrographic analysis of conditioned medium revealed that under basal conditions of culture post-confluent Caco-2 cells synthesize and secrete lipoprotein particles. Lipoproteins of density (d) less than 1.063 g/ml consist of a heterogeneous population of particles (diameter from 10 to 90 nm). This fraction consists of very low density lipoproteins (d less than 1.006 g/ml) and low density lipoproteins (d = 1.019-1.063 g/ml). Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of [35S]methionine-labeled Caco-2 lipoproteins revealed that very low density lipoproteins contain apolipoprotein E (apoE) and C apolipoproteins, while low density lipoproteins contained apoB-100, apoE, apoA-I, and C apolipoproteins. The 1.063-1.21 g/ml density fraction contained two morphological entities, discoidal (diameter 15.6 +/- 3.9 nm) and round high density lipoprotein particles (diameter 10.2 +/- 2.3 nm). The high density lipoproteins contained apoA-I, apoB-100, apoB-48, apoE, and the C apolipoproteins. Using isoelectric focusing polyacrylamide gel electrophoresis newly secreted apoA-I was identified as pro-apoA-I. ApoE and apoC-III released by Caco-2 cells were highly sialylated. mRNA species for apoA-I, apoC-III, and apoE, but not apoA-IV were identified by Northern blot analysis. ApoA-I, apoB, and apoE were visualized in Caco-2 cells by immunolocalization analysis. This intestinal cell line may be useful for in vitro studies of nutritional and hormonal regulation of lipoprotein synthesis.     

The effect of a lipid-rich diet on the properties and composition of lipoprotein particles from the Golgi apparatus of guinea-pig liver

1. A cell fraction rich in Golgi apparatus was isolated from the livers of guinea pigs fed on a lipid-rich diet (1.6% cholesterol, 15% corn oil). 2. The Golgi cisternae and secretory vesicles contained electron-dense particles which were tentatively identified as VLD (very-low-density) and LD (low-density) lipoproteins. Particles of moderate electron density, 150–500nm in diameter, were seen associated with membranous elements of the Golgi-apparatus cell fraction. Disruption of this cell fraction permitted the release of these three species of particles, which were separated into particulate lipid, and VLD and LD lipoproteins. 3. The large particles of moderate electron density, isolated as particulate lipid, were distinct from both species of Golgi particles in their chemical composition and in possessing an immunochemically unreactive apolipoprotein(s). Morphological observations suggest that the particulate lipid arose from cytoplasmic lipid droplets which were present as contaminants of the Golgi-rich fraction. 4. The chemical and immunochemical results are consistent with the suggestion that the Golgi LD particles are precursors of the VLD particles, into which they may be transformed by the addition of both triglyceride and cholesteryl ester. The present results provide further support for the proposal that the Golgi VLD particles are precursors of the serum VLD lipoproteins in the guinea pig. 5. Hepatic Golgi VLD particles isolated from guinea pigs fed on the lipid-rich diet contained significantly higher molar amounts (relative to protein) of both cholesteryl ester and triglyceride than similar particles from animals fed on a normal diet. These results suggest that the type of Golgi VLD particle produced from the LD particle is a direct consequence of the amount and composition of the dietary lipid. 6. Hepatic Golgi LD particles isolated from guinea pigs fed on different diets were similar in chemical composition and contained approx. 50% by weight of phospholipid. We conclude that the Golgi LD particle is normally present in the Golgi-apparatus cell fraction from guinea-pig liver, and may represent the end product of lipoprotein biosynthesis in the smooth endoplasmic reticulum. 7. The serum LD lipoproteins and Golgi LD particles were quite distinct in chemical composition. However, these two lipoprotein species were immunochemically identical and exhibited a similar range of flotation rate. It appears unlikely that the Golgi LD particles are secreted as the precursors of the serum LD lipoproteins.     

Assembly of very low density lipoproteins in mouse liver: evidence of heterogeneity of particle density in the Golgi apparatus

The assembly of very low density lipoproteins (VLDL) by hepatocytes is believed to occur via a two-step process. The first step is the formation of a dense phospholipid and protein-rich particle that is believed to be converted to VLDL by the addition of bulk triglyceride in a second step. Previous studies in our laboratory led us to hypothesize a third assembly step that occurs in route to or in the Golgi apparatus. To investigate this hypothesis, nascent lipoproteins were recovered from Golgi apparatus-rich fractions isolated from mouse liver. The Golgi fractions were enriched 125-fold in galactosyltransferase and contained lipoprotein particles averaging approximately 35 nm in diameter. These lipoproteins were separated by ultracentrifugation into two fractions: d < 1.006 g/ml and d1.006;-1.210 g/ml. The d < 1.006 g/ml fraction contained apolipoprotein B-100 (apoB-100), apoB-48, and apoE, while the d1.006;-1.210 g/ml fraction contained these three apoproteins as well as apoA-I and apoA-IV. Both fractions contained a 21-kDa protein that was isolated and sequenced and identified as major urinary protein. Approximately 50% of the apoB was recovered with the denser fraction. To determine if these small, dense lipoproteins were secreted without further addition of lipid, mice were injected with Triton WR1339 and [(3)H]leucine, and the secretion of apoB-100 and apoB-48 into serum VLDL (d < 1.006 g/ml) and d1.006;-1.210 g/ml fractions was monitored over a 2-h period. More than 80% of the newly synthesized apoB-48 and nearly 100% of the apoB-100 were secreted with VLDL. These studies provide the first characterization of nascent lipoproteins recovered from the Golgi apparatus of mouse liver. We conclude that these nascent hepatic Golgi lipoproteins represent a heterogeneous population of particles including VLDL as well as a population of small, dense lipoproteins. The finding of the latter particles, coupled with the demonstration that the primary secretory product of mouse liver is VLDL, suggests that lipid may be added to nascent lipoproteins within the Golgi apparatus.     

Human lymphedema fluid lipoproteins: particle size, cholesterol and apolipoprotein distributions, and electron microscopic structure

The concentration of cholesterol, apolipoproteins A-I, B, and E has been determined in lymphedema fluid from nine patients with chronic primary lymphedema. The concentrations were: 38.14 +/- 21.06 mg/dl for cholesterol, 15.6 +/- 6.17 mg/dl for apolipoprotein A-I, 7.5 +/- 2.8 mg/dl for apolipoprotein B, and 1.87 +/- 0.50 mg/dl for apolipoprotein E. These values represent 23%, 12%, 6%, and 38% of plasma concentrations, respectively. The ratio of esterified to unesterified cholesterol in lymphedema fluid was 1.46 +/- 0.45. Lipoproteins of lymphedema fluid were fractionated according to particle size by gradient gel electrophoresis and by exclusion chromatography. Gradient gel electrophoresis showed that a majority of high density lipoproteins (HDL) of lymphedema fluid were larger than ferritin (mol wt 440,000) and smaller than low density lipoproteins (LDL); several discrete subpopulations could be seen with the large HDL region. Fractionation by exclusion chromatography showed that more than 25% of apolipoprotein A-I and all of apolipoprotein E in lymphedema fluid was associated with particles larger than plasma HDL2. Apolipoprotein A-I also eluted in fractions that contained particles the size of or smaller than albumin. Isolation of lipoproteins by sequential ultracentrifugation showed that less than 25% of lymphedema fluid cholesterol was associated with apolipoprotein B. The majority of apolipoprotein A-containing lipoproteins of lymphedema fluid were less dense than those in plasma. Ultracentrifugally separated fractions of lipoproteins were examined by electron microscopy. The fraction d less than 1.019 g/ml contained little material, while fraction d 1.019-1.063 g/ml contained two types of particles: round particles 17-26 nm in diameter and square-packing particles 13-17 nm on a side. Fractions d 1.063-1.085 g/ml had extensive arrays of square-packing particles 13-14 nm in size. Fractions d 1.085-1.11 g/ml and fractions d 1.11-1.21 g/ml contained round HDL, 12-13 nm diameter and 10 nm diameter, respectively. Discoidal particles were observed infrequently.     

Formation of phospholipid-rich HDL: a model for square-packing lipoprotein particles found in interstitial fluid and in abetalipoproteinemic plasma

The major bovine HDL subfraction, fraction I-HDL, was incubated with increasing amounts of dimyristoylphosphatidylcholine (DMPC). HDL size, as determined by gradient gel electrophoresis and electron microscopy, increased with increasing HDL-phospholipid to DMPC mole ratios. Control fraction I-HDL were spherical, hexagonally-packing particles with a peak on gradient gel electrophoresis at 12.3 +/- 0.1 nm; at a ratio of 1:0.5, larger, mainly spherical particles with a peak at 12.9 +/- 0.08 nm were formed. At a ratio of 1:1, occasional square-shaped particles were seen by electron microscopy; by gradient gel analysis, the mean diameter of the HDL-product increased to 13.7 +/- 0.1 nm. At the 1:2 ratio, extensive domains of square-packing particles were noted; the major size peak of this product was 14.6 +/- 0.08 nm. In all incubations with DMPC, a small 9.4 +/- 0.08 nm product was formed; it was most pronounced at the 1:2 ratio. The large, less dense particles generated by incubation contained apolipoprotein A-I and small molecular weight proteins. The 9.4 nm product contained only apolipoprotein A-I. The less dense product formed during incubation at the 1:2 ratio had a decreased protein-to-lipid ratio relative to control HDL and a 2-fold increase in percent phospholipid. At a 1:2 ratio, incorporation of DMPC into fraction I-HDL results in the loss of one molecule of apolipoprotein A-I; the resultant particle is a stable phospholipid-rich and protein-poor HDL which has a square-packing geometry. These phospholipid-laden HDL are morphologically similar to lipoproteins isolated from interstitial fluid or from plasma of abetalipoproteinemic patients. Our data suggest that the unusual morphological properties of the latter biologically formed particles may be due to increases in the polar lipid contents, and concomitant decreases in surface protein.     

西伯利亚旱獭中类人乙肝病毒的研究

对111份西伯利亚旱獭血清标本进行血清学,形态和组织病理学检测,HBsAg阳性22份,阳性率19.8％;抗-HBs1份,阳性率0.9％;HBV-DNA核酸杂交,阳性斑点16份,阳性率14.4％。IEM观察在3份标本中发现以22—24nm球形颗粒为主,其中有42—45mm的Dane样颗粒。20.7％的肝脏标本有组织病理改变,其中19份为急性肝类,4份为慢性肝炎。超薄切片肝细胞核内有20nm左右的HBeAg颗粒,结果进一步证实我国西伯利亚旱獭中有嗜肝病毒感染。     

Comparison, by freeze-fracture electron microscopy, of chromatophores, spheroplast-derived membrane vesicles, and whole cells of Rhodopseudomonas sphaeroides.

By using freeze-fracture electron microscopy, chromatophores and spheroplast-derived membrane vesicles from photosynthetically grown Rhodopseudomonas sphaeroides were compared with cytoplasmic membrane and intracellular vesicles of whole cells. In whole cells, the extracellular fracture faces of both cytoplasmic membrane and vesicles contained particles of 11-nm diameter at a density of about 5 particles per 10(4) nm2. The protoplasmic fracture faces contained particles of 11 to 12-nm diameter at a density of 14.6 particles per 10(4) nm2 on the cytoplasmic membrane and a density of 31.3 particles per 10(4) nm2 on the vesicle membranes. The spheroplast-derived membrane fraction consisted of large vesicles of irregular shape and varied size, often enclosing other vesicles. Sixty-six percent of the spheroplast-derived vesicles were oriented in the opposite way from the intracellular vesicle membranes of whole cells. Eighty percent of the total vesicle surface area that was exposed to the external medium (unenclosed vesicles) showed this opposite orientation. The chromatophore fractions contained spherical vesicles of uniform size approximately equal to the size of the vesicles in whole cells. The majority (79%) of the chromatophores purified on sucrose gradients were oriented in the same way as vesicles in whole cells, whereas after agarose filtration almost all (97%) were oriented in this way. Thus, on the basis of morphological criteria, most spheroplast-derived vesicles were oriented oppositely from most chromatophores.     

Characterization of lipoproteins produced by the human liver cell line, Hep G2, under defined conditions

Confluent monolayers of the human hepatoblastoma-derived cell line, Hep G2, were incubated in serum-free medium. Conditioned medium was ultracentrifugally separated into d less than 1.063 g/ml and d 1.063-1.20 g/ml fractions since very little VLDL was observed. The d less than 1.063 g/ml fraction was examined by electron microscopy; it contained particles of 24.5 +/- 2.3 nm diameter, similar in size to plasma LDL; a similar size was demonstrated by nondenaturing gradient gel electrophoresis. These particles possessed apoB-100 only. The d less than 1.063 g/ml fraction had a lipid composition unlike that of plasma LDL; unesterified cholesterol was elevated, there was relatively little cholesteryl ester, and triglyceride was the major core lipid. The d 1.063-1.20 g/ml fraction was heterogeneous in size and morphology. Electron microscopy revealed discoidal particles (14.9 +/- 3.2 nm long axis and 4.5 +/- 0.2 nm short axis) as well as small spherical ones (7.6 +/- 1.4 nm diameter). Nondenaturing gradient gel electrophoresis consistently showed the presence of peaks at 13.4 11.9, 9.7, and 7.4 nm. The latter peak was conspicuous and probably corresponded to the small spherical structures seen by electron microscopy. Unlike plasma HDL, Hep G2 d 1.063-1.20 g/ml lipoproteins contained little or no stainable material in the (HDL3a)gge region by gradient gel electrophoresis. Hep G2 d 1.063-1.20 g/ml lipoproteins differed significantly in composition from their plasma counterparts; unesterified cholesterol and phospholipid were elevated and the mole ratio of unesterified cholesterol to phospholipid was 0.8. Cholesteryl ester content was extremely low. ApoA-I was the major apolipoprotein, while apoE was the next most abundant protein; small quantities of apoA-II and apoCs were also present. Immunoblot analysis of the d 1.063-1.20 g/ml fraction after gradient gel electrophoresis showed that apoE was localized in the larger pore region of the gel (apparent diameter greater than 12.2 nm); the apoA-I distribution in this fraction was very broad (7.1-12.2 nm), and included a distinct band at 7.4 nm. Immunoblotting after gradient gel electrophoresis of concentrated medium revealed that a significant fraction of apoA-I in the uncentrifuged medium was in a lipid-poor or lipid-free form. This cell line may be a useful model for investigating the metabolism of newly formed HDL.     

Characterization of two lipoproteins containing apolipoproteins B and E from lesion-free human aortic intima

Lesion-free areas of aortic intimas from seven men, 30 to 49 years old, were extracted with aqueous buffer within a few hours after an accidental or sudden death. Two lipoprotein fractions could be isolated by density gradient ultracentrifugation from all cases. The mean composition of fraction I (d less than 1.012 g/ml) resembled that reported for the cholesteryl ester-rich, beta-migrating very low density lipoprotein (beta-VLDL); the composition of fraction II (d 1.021-1.046 g/ml) resembled that of plasma low density lipoprotein (LDL). Mean diameter of the particles was 35 +/- 8 nm in fraction I and 25 +/- 5 nm in fraction II (22 +/- 2 nm in plasma LDL). Both fractions contained apolipoproteins B (apoB) and E (apoE), and had increased electrophoretic mobilities and reduced contents of linoleic acid. The immunoreactivity of apoB to a polyclonal and two monoclonal antibodies in both fractions was not different from that of plasma lipoproteins. The apoE isoform patterns in both fractions were similar to those obtained from the respective postmortem plasmas. When incubated with mouse peritoneal macrophages, fractions I and II enhanced the incorporation of radioactive oleate into cholesteryl esters by 10- to 20-fold and 3- to 4-fold, respectively, in comparison to plasma LDL. In conclusion, our results indicate that lesion-free human aortic intima contains two types of apoB- and apoE-containing lipoprotein particles, both of which might be potentially atherogenic.     

Management and husbandry of ruffed lemurs,Varecia variegata,at the San Diego Zoo. I. Captive population,San Diego Zoo housing and diet

The captive history of the ruffed lemur is presented with concentration on taxonomy, captive population and husbandry of the San Diego Zoo population. At the conclusion of 1985, the living population of black and white ruffed lemurs numbered 358; red ruffed lemurs totaled 125. The San Diego Zoo population, established between 1965 and 1970, began with two pairs of each subspecies. Intensive breeding at the Primate Propagation Center resulted in the birth of 135 black and white ruffed lemur infants and 95 red ruffed lemur infants as of January 7, 1986. Housing specifications are presented for the off-exhibit 96-unit breeding facility, describing enclosure size, material, nest box composition, and enclosure furniture. The diet is described, which emphasizes high-protein, high-fiber foods and leaves.     

Use of baculovector for the expression of HBsAg gene in insect cells

Based on the information of molecular biology of Autographa californica Nuclear Polyhedrosis virus (AcNPV), a recombinant transfer plasmid pAcMV was constructed by molecular procedures included using two synthetic localized probes, which provided an inserted position linked with BamHI sequences nearly at polyhedrin initiating ATG codon. Then an expression vector pAcMV-HBsAg was reconstructed, it contained HBsAg gene from subclone pYPSS-1 derived from adwserotype of HBV. The recombinant virus containing HBsAg gene was isolated and purified through 3 cycles plaques and hybridization experiment after cotransfection of Spodoptera frugiperda cells with DNA of pAcMV-HBsAg and AcNPV. The expression of HBsAg gene in S. frugiperda cells infected with recombinant virus AcRV-HBsAg was identified by ELISA as haemagglutination tests. The yield of HBsAg excreted from S. frugiperda cells (an appropriate density usually between 1-2 X 10(6) cells/ml) after 48-72 h infected with AcRV-HBsAg was 4-8 mg/L. HBsAg harvested from the infected culture medium was shown immunoelectromicroscopy to be composed of spherical particles of about 22 nm diameter. Using this purified HBsAg, Bal b/c mice was immunized, the titer of anti-HBsAg serum measured measured by RIA was similar to that of purified HBsAg from human blood. Stable recombinant virus was isolated and could be shown to replicate in corn borer (Ostrinia nubilalis) larvae. All of these results can be expected that this expression vector system will be commercially developed to its fullest potential for diagnosis and vaccine HBsAg.     

Preliminary biomedical evaluation of wild ruffed lemurs (Varecia variegata and V. rubra)

Complete medical examinations were performed on 11 wild ruffed lemurs (Varecia variegata and V. rubra) from three sites in Madagascar. Each animal received a complete physical examination, several physiological parameters were analyzed (complete blood count, serum biochemical profile, and fecal bacterial culture), and the animals were examined for endo-, ecto-, and hemoparasites. Additional tests were performed as samples were available, including fat-soluble vitamin analysis, trace mineral analysis, toxoplasmosis serology, and viral serology. We found that the ruffed lemurs were in good health, harbored a low endoparasite load, and frequently had external parasites (e.g., ticks (Haemophysalis lemuris)). Statistically significant differences between captive and wild lemurs were found for the following serum biochemical and blood count parameters: alanine aminotransferase (ALT), total protein (TP), albumin, blood urea nitrogen, cholesterol, glucose, amylase, band neutrophil count, and eosinophil count. Low blood urea nitrogen (BUN) and serum cholesterol values in wild lemurs (compared to those of North American captive zoo ruffed lemurs) may suggest differences between diets in the wild and captivity.