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PubMed2003

Survey of gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in Southwestern Cameroon.

A study on the distribution and population density of the western lowland gorilla (Gorilla g. gorilla) and the central chimpanzee (Pan t. troglodytes) was undertaken between December 1997 and August 2000 in the Campo and Ma'an Forests in southwestern Cameroon. The aim of this survey was to estimate the densities of the apes in different parts of the area, to assess the importance of the region for the conservation of these endangered species and to determine the influence of human activities such as logging and hunting. The survey was based on night nest counts on a total of 665.5 km of line transects. The overall density in the Campo Forest was estimated at 0.2 gorillas/km(2) and at 0.63-0.78 chimpanzees/km(2). The overall density of chimpanzees in the Ma'an Forest was estimated at 0.8-1 individuals/km(2). Gorilla density in this area was too low to allow an estimation. The highest gorilla nest density was found in secondary forest. The gorilla density in unlogged forest was significantly lower. Chimpanzees showed a clear preference for less disturbed areas. In unlogged forest, old secondary forests (logging more than 23 years ago) and areas of recent logging with large remaining patches of primary forest, significantly higher densities were calculated than inside the more heavily exploited logging concession. In areas with both logging and high hunting pressure both species were rare or even absent. The Campo Ma'an area is considered a very important area for the conservation of gorillas and chimpanzees. Conservation measures are urgently required to reduce the impact of logging and hunting. The creation of the Campo Ma'an National Park in January 2000 is an important measure to preserve the unique biodiversity in this so far hardly protected area.

Animals↗
PubMed2004

Hierarchy and social status in Budongo chimpanzees.

The status hierarchy is fundamental in the lives of male chimpanzees. This study describes the dominance interactions and social status among adult male chimpanzees of the Sonso community in the Budongo Forest Reserve, Uganda, during the period that they were first studied (1994 and 1995). Social dominance is typically measured using the behaviour of either the subordinate or the dominant individual, but a relationship is dependent on the behaviour of both parties and this study explicitly used both subordinate and dominant behaviours to investigate the status hierarchy. Among adult males of the Sonso community, agonistic interactions occurred at a low rate and pant-grunts were rare, but males could be ranked into separate hierarchies of agonistic dominance and pant-grunting (labelled 'respect') using ratios of behaviour performed/behaviour received. These hierarchies were combined to form a single hierarchy of social status that divided the males among five distinct status levels. The highest status level was held by an alliance between two males who replaced the previous alpha male during the first part of the study. Neither male in this alliance partnership pant-grunted to the other, although the reason for cooperative behaviour was unclear. Although the nominally beta male was treated as such by other adult males, he achieved surprisingly little mating success. Budongo Forest chimpanzees do not warrant the sometimes-expressed view that they are non-aggressive and peaceable and the broad pattern of their status interactions matches with that seen in other chimpanzee populations.

Agonistic Behavior↗
PubMed2004

A comparison of buttress drumming by male chimpanzees from two populations.

Wild chimpanzees ( Pan troglodytes) produce low-frequency sounds by hitting the buttresses and/or trunks of trees. This "buttress drumming" occurs in discrete bouts that may be integrated into the phrase sequence of the chimpanzee's long-distance vocalization, the "pant hoot." The aim of this study was to investigate whether regional variation exists in the drumming behavior of male chimpanzees from Kibale National Park (Kanyawara community), Uganda, and Taï National Park, Ivory Coast. Recordings were made during a 6-month field season at Taï in 1990, and a 12-month field season at Kanyawara in 1996-1997. Acoustic analysis revealed the following: (1) Kanyawara males drummed significantly less frequently in conjunction with a pant hoot or hoot than did Taï males; (2) drumming bouts by Kanyawara males included significantly fewer beats, and were significantly shorter in duration, than those of Taï males; these differences disappeared when only those bouts produced in conjunction with a call were compared; (3) when Kanyawara chimpanzees did call and drum together, they tended to integrate drumming into the vocalization at a later point than did Taï males; and (4) individual differences in the temporal patterning of drumming bouts were not apparent for Kanyawara males, whereas a previous analysis revealed individual differences among Taï males.

Animals↗
PubMed2006

Sniffing behaviors in Mahale chimpanzees.

Although it is difficult for observers to determine how non-human primates use olfaction in a natural environment, sniffing is one clue. In this study, the sniffing behaviors of wild chimpanzees were divided into six categories, and sex differences were found in most categories. Males sniffed more frequently than females in sexual and social situations, while females sniffed more often during feeding and self-checking. Chimpanzees sniffed more frequently during the dry season than during the wet season, presumably due to the low humidity. This suggests that the environment affects olfactory use by chimpanzees and that chimpanzees easily gather new information from the ground via sniffing.

Animals↗
PubMed1978

Sex differences, dominance, and personality in the chimpanzee.

This study demonstrates a useful methodology for judging the personality of chimpanzees (Pan troglodytes schweinfurthi). Observers rated the chimpanzees on a forced-choice rating scale which yielded measures on eight emotion dimensions. The rating scale, Emotions Profile Index, is derived from a theory of personality which stresses the adaptive significance of emotions at all evolutionary levels. This method has theoretical generality, having been successfully applied previously to humans, baboons and dolphins. Observers were able to rate chimpanzees with reasonable reliability. Sex differences in personality were evident in this chimpanzee sample. In addition, dominance rank was found to correlate with certain emotion dimensions.

Aggression↗
PubMed1983

Impaired renal function in diabetic chimpanzees (Pan troglodytes).

Studies were conducted to assess the renal functional state in two recently discovered diabetic chimpanzees. Both were nonobese, adult female animals with the non-insulin-dependent form of impaired glucose tolerance, analogous to the Type II or nonobese, maturity-onset diabetes of humans. Both animals displayed moderate-to-heavy proteinuria and glycosuria in response to intravenous administration of glucose or tolbutamide. Chimpanzee number 333, but not number 1037, had fasting proteinuria and chronic hypertension. Renal function studies, using the inulin clearance method, demonstrated significantly decreased glomerular filtration rates and elevated rates of sodium excretion for both animals. The rate of chloride excretion was also elevated in animal number 1037, but potassium excretion was apparently unaffected in both animals. Abnormal serum biochemical parameters demonstrated for chimpanzee number 333 included elevations in calcium, magnesium, creatinine, urea nitrogen, and uric acid; animal number 1037 had only an elevated serum creatinine. Results are consistent with the occurrence of renal disease similar to the nephropathy that develops in human diabetics. The difference in severity of renal impairment in the two chimpanzees is possibly related to differences in duration and severity of impaired glucose tolerance. A progression of both diabetic and renal disorders is most probable.

Animals↗
PubMed1990

Parenterally transmitted non-A, non-B hepatitis: virus-specific antibody response patterns in hepatitis C virus-infected chimpanzees.

An established chimpanzee model of parenterally-transmitted non-A, non-B hepatitis was used to define virus-specific immune response patterns in acutely and persistently infected animals. Serial bleedings were obtained from 23 chimpanzees that had been experimentally infected with an isolate of hepatitis C virus, originally recovered from contaminated lots of factor VIII (antihemophilic) materials. Sera were assayed for the presence of antihepatitis C virus by a newly developed radioimmunoassay procedure that incorporated recombinant DNA-expressed viral antigen as a reagent. Twenty-one of 23 hepatitis C virus infected animals were shown to acquire antihepatitis C virus, most within 2-8 weeks after the major peak of alanine aminotransferase activity. All chimpanzees with biochemical, electron microscopic, and histological evidence of chronic disease clearly acquired antibody; 14 of 16 animals observed through the acute phase of disease were also shown to acquire antibody. A booster effect or anamnestic response was noted in two chimpanzees (one of which was negative for antihepatitis C virus following the acute phase of disease) after challenge with hepatitis C virus. Antihepatitis C virus was not neutralizing, because some animals with high levels of antibody were also shown to have high titers of circulating hepatitis C virus. The development and maintenance of anti-hepatitis C virus appears to reflect concomitant virus replication and high potential for infectivity.

Animals↗
PubMed1996

Comparative analysis of apoptosis in HIV-infected humans and chimpanzees: relation with lymphocyte activation.

Programmed-cell death (apoptosis) is a physiological cell death process which appears exacerbated in peripheral lymphocytes from HIV-infected persons. On the contrary, a barely detectable level of apoptosis is found in peripheral lymphocytes from HIV-infected chimpanzees, which support long-term productive infection without developing AIDS. In the present study, we analyzed the relationship between apoptosis and the general state of immune activation in PBMC from HIV-infected humans and chimpanzees. In addition, apoptosis control in the CD8 subset by the bcl-2 proto-oncogene was compared in both human and chimpanzees. Taken together, the results indicate that the degree of apoptosis correlates with the state of activation of the immune system and this observation together with the finding that apoptosis concerns all lymphocyte subsets indicates that the low level of apoptosis in HIV-infected chimpanzees is related to the lack of immune activation in this nonpathogenic model.

Animals↗
PubMed1996

Categorization in monkeys and chimpanzees.

Studies on the classificatory ability of non-human primates are reviewed. The evidence suggests that there are important differences in the degree to which monkeys and chimpanzees detect same/different relations and construct classes that embody these relations. Data on matching to sample performance suggest that monkeys have a limited capacity for abstract representation of identity relations between individual objects. Chimpanzees, by contrast, not only detect similarities and differences between individual objects at a more abstract level than monkeys, but can also perceive same/different relations between pairs of objects. Further evidence for such cognitive differences between monkeys and chimpanzees comes from data on the development of spontaneous classificatory behavior. Monkeys develop first-order classifying. Their spontaneous spatial groupings are restricted to elements from one class. Chimpanzees progress from first-order to elementary second-order classifying. At 5 years of age they are capable of composing two contemporaneous sets in which objects are identical or similar within each set and different between sets.

Animals↗
PubMed1989

Failure of hepatitis B immune globulin to protect against exp infection in chimpanzees.

To study experimentally the protective effect of post-exposure prophylaxis against hepatitis B (HB), a special preparation of hepatitis B immune globulin (HBIG) was injected intravenously (i.v.) into three chimpanzees simultaneously with, or at different time intervals after, intravenous injection of a titred inoculum of hepatitis B virus (HBV). The HBIG was given either simultaneously with the HBV inoculum, at 4 hours after, or at both 4 hours and 4 weeks after the HBV injection. A fourth chimpanzee received a standard preparation of HBIG intramuscularly (i.m.) at both 4 hours and 4 weeks after receiving the HBV injection. A fifth animal received HBIG i.v. 4 hours after the HBV inoculum and at the same time received its first of three HB vaccine injections. All chimpanzees were followed for 1 year. The animals which received HBIG simultaneously with HBV or received HBIG plus vaccine had no serological or biochemical sign of HB during follow-up. The three animals which received HBIG after HBV inoculation all developed HBs-antigenemia and serum aminotransferase (ALT) elevations. HBsAg did however appear in serum several weeks later than expected for the HBV inoculum used. Post-exposure prophylaxis with HBIG did protect the HBV-exposed chimpanzees, only if HBIG was combined with HB-vaccination or if HBIG was given simultaneously with the HBV inoculum.

Animals↗
PubMed1990

The significance of infections with two types of viral hepatitis demonstrated by histologic features in chimpanzees.

In view of the recognized importance of necroinflammatory episodes in chronic hepatitis B virus (HBV) infection, chimpanzees, either HBV surface antigen (HBsAg) carriers or noninfected (naive), were infected with other primary hepatotropic viruses to evaluate histologic alterations and changes in virologic and biochemical markers of infection. The advantages of studies on chimpanzees are the availability of serial biopsy specimens and the viral type-specific histologic lesions, not as well recognized in humans. Infection with hepatitis A and non-A, non-B (NANB) agents produced more severe lesions in chronic HBsAg carrier chimpanzees than in naive animals. During this superinfection, the specific expression of the second agent was predominant, indicating that the exacerbation is caused by the second agent, but that carriers are prone to more severe disease than the naive chimpanzees. Hepatitis delta virus (HDV) infections were always coexistant with HBV and superinfection of carriers produced histologic changes more severe than those seen in any other type of viral hepatitis. Such HDV infections revealed less evidence of lymphocytotoxicity but rather of cytotoxicity, and sometimes resembled in appearance the histopathology of NANB. Coinfection of HDV and HBV and superinfection of HBV-carriers with NANB resulted in hepatitis that was far less severe than superinfection of HDV in HBV carriers, greatly in keeping with human experiences. HBV replication was suppressed transiently in both NANB and HDV superinfection. This implies that in exacerbations during chronic HBV infections of humans, suppression of HBV replication markers indicates superinfection, for instance, by NANB for which markers are so far not widely available; by contrast, elevated markers of HBV replication suggest reactivation of the original HBV infection.

Animals↗
PubMed1988

Temporal development of cross-neutralization between HTLV-III B and HTLV-III RF in experimentally infected chimpanzees.

Sera from chimpanzees inoculated respectively with HTLV-III B, LAV, HTLV-III RF and brain tissue from an AIDS patient were analysed for neutralizing activity by two methods: a cell fusion inhibition test (CFI) using HTLV-III B infected cells as inoculum and CD4+ cells as target and a replication inhibition test (RIT) using cell-free HTLV-III B as well as HTLV-III RF as inoculum and also CD4+ cells as target. All chimpanzees seroconverted for HTLV-III B antibodies within 2 months after inoculation and the ten sera included in the study recognized the HTLV-III B core proteins p17 and p24 and the transmembrane protein gp41 by immunoblotting. The HTLV-III B external envelope gp120 was recognized by eight sera with antibodies active in the CFI (CFI-Ab) or in the RIT (VN-Ab) using HTLV-III B as inoculum, while neither of two sera without such reactivity did. HTLV-III B CFI-Ab and HTLV-III B VN-Ab concurred in nine of ten serum samples. LAV and HTLV-III B infection induced HTLV-III B CFI-Ab and HTLV-III B VN-Ab within 9 months after inoculation in all four chimpanzees tested. However, only the serum of one of the four animals also neutralized HTLV-III RF. HTLV-III RF inoculation evoked only HTLV-III RF VN-Ab within nine months. Between 11 and 18 months neutralizing activity to both HTLV-III B and HTLV-III RF was found in all four sera of chimpanzees inoculated with HTLV-III B, LAV or HTLV-III RF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Evaluation in chimpanzees of vaccinia virus recombinants that express the surface glycoproteins of human respiratory syncytial virus.

The immunogenicity and protective efficacy of recombinant vaccinia viruses that express the two major protective antigens of human respiratory syncytial virus (RSV), the F and G glycoproteins, were evaluated in chimpanzees. In previous studies in rodents and monkeys the F and G proteins expressed by the same recombinants were highly immunogenic and induced high levels of resistance to RSV replication following subsequent challenge. In contrast, in chimpanzees, a single intradermal immunization induced only moderate levels of F and G-specific serum antibodies as measured by an enzyme-linked immunosorbent assay, and these antibodies did not efficiently neutralize RSV infectivity in vitro. This poor antibody response in chimpanzees to the F and G glycoproteins occurred despite efficient replication of the vaccinia virus vector as evidenced by lesion size and serum antibody response to vaccinia virus. Upon intranasal RSV challenge, it was observed that prior immunization with the F and G recombinants effected only a marginal reduction in the magnitude and duration of RSV shedding from the nose and trachea and did not reduce illness. However, the RSV challenge induced a strong secondary antibody response, resulting in very high titres (greater than 8000 reciprocal mean titre) of serum neutralizing antibodies. The poor protective efficacy observed here is discussed with regard to the permissiveness of the chimpanzee to RSV replication, the general requirements for effective immunization against RSV, and the limitations of experimental animals for evaluating candidate RSV vaccines.

Animals↗
PubMed1995

Cold-passaged, temperature-sensitive mutants of human respiratory syncytial virus (RSV) are highly attenuated, immunogenic, and protective in seronegative chimpanzees, even when RSV antibodies are infused shortly before immunization.

A cold-passaged (cp) temperature-sensitive (ts) RSV mutant, designated RSV cpts-530, which possesses host-range mutations acquired during 52 passages at low temperature in bovine tissue culture and one or more ts mutations induced by chemical mutagenesis (shut-off temperature 39 degrees C) was found previously to be tenfold restricted in its replication in mice as compared to wild-type virus and stable genetically in nude mice. In the current study, we introduced additional attenuating mutations, such as small-plaque (sp) or ts mutations, into cpts-530 by chemical mutagenesis with 5-fluorouracil, with the intent of obtaining derivatives of cpts-530 that were more attenuated in mice or chimpanzees and that were more stable genetically following replication in vivo. Fourteen mutants of RSV cpts-530 which had acquired an additional ts mutation were identified and found to be more restricted in replication in BALB/c mice than the cpts-530 parental strain. One mutant, designated cpts-530/1009 (shut-off temperature 36 degrees C), was 30 times more restricted in replication in the nasal turbinates of mice and threefold more restricted in the nasopharynx of seronegative chimpanzees than its cpts-530 parent. Like its parent, this mutant was highly restricted (30,000-fold) in replication in the lower respiratory tract of chimpanzees even following direct intratracheal inoculation. The cpts-530 and cpts-530/1009 mutants exhibited a high level of stability of the ts phenotype during replication in chimpanzees.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Novel use of a chimpanzee pseudogene for chromosomal mapping of human cytochrome c oxidase subunit IV.

We have isolated a chimpanzee processed pseudogene for subunit IV of cytochrome c oxidase (COX; EC 1.9.3.1) by screening a chimpanzee genomic library in lambda Charon 32 with a bovine liver cDNA encoding COX subunit IV (COX IV), and localized it to a 1.9-kb HindIII fragment. Southern-blot analysis of genomic DNA from five primates showed that DNAs from human, gorilla, and chimpanzee each contained the 1.9-kb pseudogene fragment, whereas orangutan and pigtail macaque monkey DNA did not. This result clearly indicates that the pseudogene arose before the divergence of the chimpanzee and gorilla from the primate lineage. By screening Chinese hamster x human hybrid panels with the human COX4 cDNA, we have mapped COX4 genes to two human chromosomes, 14 and 16. The 1.9-kb HindIII fragment containing the pseudogene, COX4P1, can be assigned to chromosome 14, and by means of rearranged chromosomes in somatic cell hybrids, to 14q21-qter. Similarly, the functional gene, COX4, has been mapped to 16q22-qter.

Amino Acid Sequence↗
PubMed1991

Cloning and nucleotide sequence of the chimpanzee c-myc gene.

A DNA fragment covering the chimpanzee c-myc locus was cloned from the DNA of peripheral blood lymphocytes, sequenced, and compared to its human c-myc counterpart. The two nucleotide sequences were found to be highly homologous (99%). The divergence rate between the two species was 0.4% in exons and 1.7% in introns. The different TATA-boxes described in the human myc gene were also identified in the chimpanzee sequence and an open reading frame (ORF) was observed which overlaps the chimpanzee c-myc first exon. This latter ORF contained three silent mutations with regard to the human region, whereas the chimpanzee Myc oncoprotein coded by exons 2 and 3 differed by two amino acids from the human one.

Animals↗
PubMed1991

Characterization of the transcription unit and two processed pseudogenes of chimpanzee triosephosphate isomerase (TPI).

Three members of the chimpanzee TPI (encoding triosephosphate isomerase) gene family, the transcription unit and two processed pseudogenes, have been characterized by genomic blotting and nucleotide sequence analysis. The bona fide TPI gene spans 3.5 kb with seven exons and six introns, and is the first hominoid TPI gene to be completely sequenced. The chimpanzee gene exhibits a very high degree of sequence identity with human and rhesus TPI genes. For example, the polypeptides of 248 amino acids (aa) encoded by the chimpanzee and human TPI genes are identical, but the codons for five of these aa differ in the third codon wobble position. No alternative splice sites could be identified in the intervening sequences of the gene and, thus, the molecular basis for the synthesis of the proliferation-specific TPI isozyme observed in hominoids remains elusive. An Alu member occurs upstream from one of the processed pseudogenes, and short sequences with significant identity to the primate LINE-1 element flank the region encompassing the Alu member and TPI pseudogene. A solitary endogenous retroviral long terminal repeat occurs within the structural region of the other processed pseudogene. The ages of the processed pseudogenes are estimated to be 2.6 and 10.4 million years, implying that one was inserted into the genome before and one after the divergence of the chimpanzee and human lineages.

Amino Acid Sequence↗
PubMed1991

Cleavage of chimpanzee secretory immunoglobulin A by Haemophilus influenzae IgA1 protease.

Immunoglobulin (Ig)A proteases synthesized by human mucosal pathogens have a unique specificity for human IgA and will not cleave IgA from other species. In contrast, animal pathogens have not reliably been shown to cleave IgA of the animals they infect. This lack of an animal model has prevented an understanding of the importance of IgA1 proteases as virulence factors. One strategy to develop an animal model would be to identify a species capable of infection by a human IgA-producing pathogen whose IgA was susceptible to cleavage by IgA1 protease of that bacterium. The chimpanzee can be infected with Haemophilus influenzae and is closely related immunologically to man. For these reasons it was sought to determine whether chimpanzee secretory IgA (SIgA) is susceptible to cleavage by IgA1 protease of H. influenzae. This report shows that chimpanzee SIgA can indeed be cleaved at the hinge region by H. influenzae IgA1 protease into Fab alpha and (Fc alpha)2.SC fragments. The susceptibility of chimpanzee SIgA to IgA1 protease of a human pathogen could serve as the basis of an animal model to determine the importance of IgA1 protease in pathogenesis.

Animals↗