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LTRs are sequence elements in retroviruses and retrotransposons which are difficult to align due to their variability. One way of handling such cases is to use Hidden Markov Models (HMMs). In this work HMMs of LTRs were constructed for three groups of orthoretroviruses: the betaretroviruslike human MMTV-like (HML) endogenous retroviruses, the lentiviruses, including HIV, and gammaretroviruslike human endogenous retroviruses (HERVs). The HMM-generated LTR alignments and the phylogenetic trees constructed from them were compared with trees based on alignments of the pol gene at the nucleic acid level. The majority of branches in the LTR and pol based trees had the same order for the three retroviral genera, showing that HMM methods are successful in aligning and constructing phylogenies of LTRs. The HML LTR tree deviated somewhat from the pol tree for the groups HML3, HML7 and HML6. Among the gammaretroviruslike proviruses, the exogenous Mouse Leukemia Virus (MLV) was highly related to HERV-T in the pol based tree, but not in the LTR based tree. Aside from these differences, the similarity between the trees indicates that LTRs and pol coevolved in a largely monophyletic way. 相似文献
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This study evaluated the influence of Westernised and traditional African diets on biochemical and haematological profiles in vervet monkeys (Cercopithecus aethiops). Twelve adult male vervet monkeys bred at the Medical Research Council, all over 4 years of age and weighing more than 5 kg each, were divided into two groups of six individuals. These monkeys were raised on a standard in-house diet post-weaning, before they were fed for 8 weeks on diets containing milk solids (17.2%) or maize + legume (17.4%), as sources of high crude protein (+/- 3.5 g/kg). High protein diets had no significant effect on serum biochemical indices such as aspartate aminotransferase (AST) and gamma glutamyl transferase (GGT) concentrations (P > 0.10). However, alanine aminotransferase (ALT) concentrations were significantly higher during week 8 (P < 0.05) for the maize + legume protein group. Alkaline phosphatase (ALP; P < 0.07), total protein (P < 0.0001), albumin (P < 0.02), and bilirubin (P < 0.003) were elevated in the milk solids group, while glucose levels were also significantly higher for the milk solids group (P < 0.05) between weeks 2 and 6. Elevated protein intake had no significant effect on haematological parameters such as red blood cells (RBC), platelet and white blood cell (WBC) counts, haemoglobin levels and monocyte and neutrophil concentrations (P > 0.10). In contrast, serum lymphocyte levels were significantly raised in the maize + legume protein group (P = 0.03), whereas values for the haematocrit (P < 0.002), mean cell volume (MCV; P < 0.03) and mean corpuscular haemoglobin concentration (MCHC; P < 0.0001) were higher in the monkeys that were fed the milk solids. This investigation showed that the type of dietary protein that is consumed may well affect certain biochemical and haematological indices in vervet monkeys. Compared to the group that were given the traditional African food regime, the animals on the Western-type milk solids diet showed significant elevations in a number of important biological indicators. However, longer-term studies should be completed in this area if we are to make firmer conclusions regarding the link between the nature of dietary proteins that are consumed and its effect on metabolism. 相似文献
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We examined vervet monkey (Chlorocebus pygerythrus) space use using GPS/UHF telemetry data from 10 vervet monkeys across six troops over 9 months within a 420 ha suburban eco‐estate. We documented a mean home range of 0.99 km2 (95% MCP) and 1.07 km2 (95% KDE) for females (n = 6), 1 km2 (95% MCP) and 1.50 km2 (95% KDE) for males (n = 4) and 0.87 km2 (95% MCP) and 1.12 km2 (95% KDE) for troops (n = 6), respectively, indicating that males and larger troops had larger home ranges. These relatively small home ranges included shared territorial boundaries and high home range overlap. Vervet monkey movements indicated higher morning activity levels, and habitat selection indicated significantly more use of golf course, urban residential and forest, thicket and woodland areas, and avoidance of wetland, grassland and shrub, and urban built‐up areas. Our results suggest that modified habitat use by vervet monkeys is a consequence of behavioural facilitation to access highly available food resources, thereby facilitating their persistence in green spaces in urban areas of South Africa. Conflict management is dependent on the conservation of sufficient natural habitats and food resources, to minimise their dependence on anthropogenic supplementary food resources and consequently reduce human–monkey conflict. 相似文献
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Lynn A. Fairbanks 《International journal of primatology》1988,9(5):425-441
Social relationships of 30 infants with their maternal grandmothers were studied in a captive colony of vervet monkeys (Cercopithecus aethiops sabaeus).Grandmothers and grandinfants formed affiliative relationships with one another that could be distinguished from the infant’s
relationships with nonkin adult females and with other adult female kin. The intensity of the grandmother—grandinfant relationship
varied according to several factors which were related to the infant’s vulnerability to mortality and to the grandmother’s
ability to provide effective social support. High-ranking grandmothers spent more time near their grandinfants, and initiated
more grooming and caretaking of their grandinfants, than did lower-ranking grandmothers. Grandmothers spent more time near
their daughter’s first surviving infant than near later-born infants, and when grandmothers had more than one adult daughter,
they spent more time near the infant of the younger daughter. These results, combined with the fact that the presence of a
maternal grandmother has been associated with a reduction in the rate of infant mortality in this colony (Fairbanks and McGuire,
1986), suggest that grandmothers are actively contributing to the reproductive success of their adult daughters and to the
survival of their infant grandoffspring. 相似文献
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Jack R. Hurov 《American journal of primatology》1982,2(2):211-213
The frequency of use of diagonal walking by three motorically immature vervet monkeys (Cercopithecus aethiops) is discussed. The subjects were housed at The Balcones Research Center (Austin, Texas) and ranged from 15–105 days of age. Mixed longitudinal data taken from film indicated that lateral walknig was the first gait employed by the infant vervets studied, but that diagonal walking completely replaced lateral walking by 81 days of age. These data were compared with those of captive infant Macaca mulatta, and feral infant Papio anubis. General agreement was found regarding onset and frequency of use of diagonal walking in the three genera. 相似文献
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