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1.
Fetal hemoglobin in newborn baboons, Papio cynocephalus   总被引:1,自引:0,他引:1  
Hemoglobins from a newborn baboon, Papio cynocephalus, and from a 15-day-old baboon of the same species were examined for electrophoretic properties of polypeptide chains and were tested for alkali resistance. Hemoglobin of newborn P. cynocephalus appears to be analogous to human fetal hemoglobin. Hemoglobin of newborn P. cynocephalus is composed of α-like and γ-like chains and hemoglobin of adult P. cynocephalus is composed of α-like and β-like chains.  相似文献   

2.
Recently,Yoshikawa andDeguchi (1992) reported an unusually high frequency (40%) of two-rooted maxillary canines inMacaca fuscata females and a complete absence of this trait in males. In the present study, canine root development and morphology was examined using cephalographs taken on 50 male and 50 femaleMacaca nemestrina, and 20 male and 20 femalePapio cynocephalus for comparison with the Japanese macaque. The results showed no double-rooted canines present in either species in the upper or lower canines. This supports the general rule that, among primates, canines possess a single-root. It was further suggested that the two-rooted canines inM. fuscata may be the result of the founder effect, i.e. that the genes for this trait may have been carried by the initial populations when they arrived on the islands sometime during the middle to late Pleistocene.  相似文献   

3.
This paper describes the behavior and activity patterns of a solitary adult male yellow baboon (Papio cynocephalus) living in the Amboseli National Park, Kenya. Social events surrounding the male's departure from his group, his contacts with other baboons while solitary, and events surrounding his return to the group are described in detail. The distribution of the male's time among several activity states, called histime budget, the average duration of these activities and the autocorrelation of activity states are analyzed and compared to the same measures of activity taken on group living males. The information presented indicates that a solitary male, even when injured, is not necessarily destined to die or to have a low reproductive potential.  相似文献   

4.
Behavioral development was observed for the first 3 months of life on 18 infants from three troops of yellow balloons (Papio cynocephalus) in Mikumi National Park, Tanzania. Developmental rates were determined for each subject on six major behaviors using the slope from regression equations performed on developmental functions changes in behavior with age. These slopes were examined statistically for associations with social and physical variables that were hypothesized to influence developmental rates. Results showed that faster rates of development were significantly associated with certain environmental and social conditions. Infants born late in their cohort, infants born in a more physically immature state, infants living in a large troop, and female infants of low ranking mothers all had significantly faster rates of development than infants at the other extreme in these categories. These results are interpreted as evidence for developmental processes that compensate for environmental or physical conditions that negatively influence survivorship. © 1995 Wiley-Liss, Inc.  相似文献   

5.
The objective of this study is to assess the effects of short-term maternal deprivation (birth to 12 weeks) followed by peer group rearing on the development of aggressive and subordinate behaviors in papio monkeys (superspecies – Papio cynocephalus). Nursery reared monkeys (34 males and 30 females) were compared with mother-peer reared monkeys (11 males and 12 females) in late infancy (6 to 12 months of age) and at the end of their juvenile stage (36 to 42 months of age) in social groups composed of 75% nursery reared subjects and 25% mother reared subjects. Focal animal data were analyzed with a repeated measure ANOVA model. In general, the nursery reared infants tended to be less aggressive than mother-peer reared infants and performed less dominance behaviors, such as displace. Significant sex differences were present in the performance of aggressive (♂ > ♀) and subordinate (♂ > ♀) behaviors. Significant age differences were observed, with infants having consistently higher rates of performance.  相似文献   

6.
Two populations of baboons in Kenya, often given different specific names, Papio doguera and Papio cynocephalus, were the subject of this investigation. We conducted a field study to determine if these two populations are the same or two different species. We located a zone of contact between the two putative species in the area of Simba Springs and Ithumba Hill. The population in this area was found to represent intergradation on the basis of field observations and detailed metric observations of the morphology. The morphology of this population appears to be intermediate between that of the two populations: the olive baboon, labeled Papio doguera, and the yellow baboon, labeled Papio cynocephalus. We confirmed the findings by statistical analyses of osteometric data. Since the specific separation of the two taxa studied in this investigation is invalid, both are placed in the prior nomen, Papio cynocephalus (Linnaeus, 1766) separating them on the subspecific level, P. c. doguera and P. c. cynocephalus.  相似文献   

7.
We exposed naive Siberain polecats (Mustela eversmanni) (aged 2, 3, and 4 months) to a swooping stuffed great horned owl (Buho virginianus) and a stuffed badger (Taxidae taxus) mounted on a remote control toy automobile frame. The first introduction to each was harmless, the second was accompanied by a mild aversive stimulus, the third (1 day after attack) was harmless, and the fourth (30 days after attack) was harmless. Alert behavior increased after a single attack by either predator model. Escape responses of naive polecats did not differ between ages when exposed to the badger, but 4 month old polecats reduced their escape times after a single badger attack. When exposed to the swooping owl, naive 4 month old polecats redponded more quickly than the other two age groups, and 3 and 4 month old polecats reduced escape times after a single owl attack. This indicates an innate escape response to the owl model at 4 months of age, and a short-tert ability to remember a single mild aversive encounter with the badger and owl models at 3 or 4 months of age.  相似文献   

8.
Longitudinal data from a population of yellow baboons,Papio cynocephalus, in the Amboseli National Park, Kenya, provide life history parameter estimates. Females reached menarche at approximately four-and-a-half years of age and then cycled for approximately a year before first conception. Postpartum anestrum averaged 12 months but ranged from six to 16 months. In cases of still births or infant death during postpartum amenorrhea, females commenced cycling after approximately one month. In mature females the time spent cycling before conception was five months on the average with a range from one to over 18 months. Only half of all full-term pregnancies resulted in infants who survived the first year of life; only a third, in infants who survived until the birth of their mother’s next infant. In comparison with data from laboratory colonies, our data indicate that female baboons in Amboseli are older at birth of first infant. They have, on the average, a somewhat shorter interbirth interval than was estimated from earlier crossectional field data, and therefore spend a larger portion of their adult life pregnant, but have a much longer interval—at least three years on the average—between the birth of an infant and the birth of that infant’s next older surviving sibling. A number of morphological changes in immature baboons are described.  相似文献   

9.
Thyroxine (T4) and triiodothyronine (T3) plasma concentrations have been determined during 24-hr sampling periods in six mongrels (age 12-36 months), six beagles (age 35-37 months), three labradors (age 3.5 months) and three beagles (age 5 months). The mean T4 levels of the labradors were significantly lower than the values found for mongrels or older beagles (P < 0.05), whereas T3 was higher in the 5 month old beagles compared to the mongrels (P < 0.001), young beagles (P < 0.05) or labradors (P < 0.01).

Circadian and ultradian rhythmicities have been evaluated by cosinor and Fourier analysis. Mongrels and older beagles did have a 12-hr rhythmicity in plasma T4 (P < 0.05), whereas 5 month old beagles had a circadian one (P < 0.01). A 12-hr rhythmicity was also found for T3 in the older Beagles (P < 0.05). However, Fourier analysis indicated that the daily variation in T4 and T3 plasma levels was inadequately mathematically described by single sinusoidal rhythm and that more harmonic components are to be taken into account.

The obtained data during a 24-hr period indicate that T4 and T3 concentrations in plasma may vary according to breed, age and sampling hour.  相似文献   

10.
The biology of reproduction was investigated in 631 specimens of Synodontis schall taken from the White Nile near Khartoum. Morphological changes of the gonads were followed for twelve months and the results used to classify their different developmental stages and maturity. Water and ash content of the gonads varied slightly from month to month and this variation was more pronounced during the breeding season. Gonosomatic indices also varied in the same manner. Synodontis schall spawns from July to September and females are ripe at the early age of I. Absolute fecundity ranged from 10 000 to 90 000 eggs and was highly correlated with growth parameters such as length, weight and age. Variations in the diameter of the eggs during the breeding season were also followed.  相似文献   

11.
Indoleamine 2,3 dioxygenase (Ido1), the first and rate‐limiting enzyme of the kynurenine pathway (KP), is a striatally enriched gene with increased expression levels in the YAC128 mouse model of Huntington disease (HD). Our objective in this study was to delineate age‐related KP alterations in this model. Three enzymes potentially catalyze the first step of the KP; Ido1 and Indoleamine 2,3 dioxygenase‐2 were highly expressed in the striatum and Tryptophan 2,3 dioxygenase (Tdo2) in the cerebellum. During development, Ido1 mRNA expression is dynamically regulated and chronically up‐regulated in YAC128 mice. Kynurenine (Kyn) to tryptophan (Trp) ratio, a measure of activity in the first step of the KP, was elevated in YAC128 striatum, but no change in Tdo2 mRNA levels or Kyn to Trp ratio was detected in the cerebellum. Ido1 induction was coincident with Trp depletion at 3 months and Kyn accumulation at 12 months of age in striatum. Changes in downstream KP metabolites of YAC128 mice generally followed a biphasic pattern with neurotoxic metabolites reduced at 3 months and increased at 12 months of age. Striatally specific induction of Ido1 and downstream KP alterations suggest involvement in HD pathogenesis, and should be taken into account in future therapeutic developments for HD.  相似文献   

12.
Infants of known birthdates were sampled from a population of yellow baboons (Papio cynocephalus) in Mikumi National Park, Tanzania, to ascertain the reliability of several maturational changes which could be used to age infants whose birthdates are unknown. The transition from the infant's black natal coat to the uniform yellow or tan adult pelage proved extremely variable, with completion varying from 7 to 19 months. The transition from the pink skin of the newborn to the completely grey adult pigmentation was much less variable. Skin on the hands and feet and on the paracallosal area was completely grey in all individuals by 8 months, while skin on the face and ears changed more gradually and was entirely grey by 12 months. These data are in substantial agreement with maturational markers established for yellow baboon infants in Amboseli National Park, Kenya, despite differences in habitat and age-sex structure between the two populations.  相似文献   

13.
Measurement of cortisol concentration can contribute important information about an individual's ability to adjust to various environmental demands of both physical and psychosocial origin. However, one uncertainty that affects the possibilities of correctly interpreting and designing field studies is the lack of observations of the impact of seasonal changes on cortisol excretion. For this reason, the month‐to‐month changes in diurnal cortisol concentration, the awakening cortisol response (ACR), maximum morning concentration, and fall during the day were studied in a group of 24 healthy men and women 32 to 61 yrs of age engaged in active work. On one workday for 12 consecutive months, participants collected saliva at four time points for determination of cortisol: at awakening, +30 min, +8 h, and at 21:00 h. Data were analyzed by a repeated measures design with month (12 levels) and time‐of‐day (4 levels) as categorical predictors. Cortisol concentrations were analyzed on a log scale. The diurnal pattern of cortisol was similar across months (interaction between month and time of day: p>0.4). The main effects of month and time‐of‐day were statistically significant (p <0.001). Highest concentrations were observed in February, March, and April, and lowest concentrations were observed in July and August. There were no statistically significant effects in any of the other measures, or between men and women. In conclusion, a seasonal variation in salivary cortisol concentrations was detected in an occupationally active population. Thus, seasonal variation needs to be taken into account when designing and evaluating field studies and interventions and when making comparisons across studies.  相似文献   

14.
Dental eruption schedules previously used to age wild baboons have in the past derived from studies of captive animals housed under standard conditions and fed standard laboratory diets. This paper reports for the first time eruption schedules derived from wild baboons, the yellow baboons (Papio hamadryas cynocephalus) of Mikumi National Park, Tanzania, and compares these schedules with those of other baboon subspecies inhabiting both similar and dissimilar environments. Eighteen males and twelve females from the Viramba groups, ranging in age from 21 to 103 months, were trapped, and dental impressions and notes were made of the state of eruption of each tooth. Eruption of all teeth were delayed at Mikumi relative to the baboon standards derived from the captive animals at the Southwest Foundation for Biomedical Research, San Antonio, Texas. Teeth of the canine-premolar 3 complex and third molars were most delayed, erupting up to a year and a half later than their counterparts from captive animals. Comparison with data on hamadryas baboons from Erer-Gota in Ethiopia revealed that both the hamadryas and yellow subspecies of baboons, with different genetic backgrounds and living under markedly different environmental conditions, followed the same schedule. This constancy of developmental schedules suggests that these Mikumi data may reasonably be used as standards for other wild baboon populations and that acceleration of dental maturation, as well us maturation of other somatic systems in captivity, is another manifestation of the short-term adaptive plasticity of the baboon species as a whole.  相似文献   

15.
Objective: Ghrelin is postulated to be an orexigenic signal that promotes weight regain after weight loss (WL). However, it is not known whether this putative effect of ghrelin is sustained after weight stabilization. The objective of this study was to investigate the relationship of plasma ghrelin concentrations to active WL and weight maintenance in obese subjects. Research Methods and Procedures: This study was a randomized clinical trial, with a 12‐month follow‐up period. Obese Mexican‐American women matched for age and BMI were randomized to a 12‐month WL program (n = 25) or no intervention (controls, n = 23). Interventions included diet, exercise, and orlistat. Body weight and fasting ghrelin, leptin, insulin, and glucose concentrations were measured at baseline and 6 and 12 months. Results: The WL group lost 8.5% of body weight after 6 months and maintained the new weight for the next 6 months. Ghrelin concentrations increased significantly at 6 months but returned to baseline at 12 months. Baseline ghrelin concentrations were directly related to the degree of WL achieved after 12 months. Controls experienced no change in BMI or ghrelin levels. There were no associations between plasma ghrelin and leptin or insulin concentrations. Discussion: Consistent with previous results, ghrelin rises in response to WL, perhaps as a counterregulatory mechanism. However, the present results indicate that ghrelin concentrations return to baseline with sustained weight maintenance, suggesting that its effects are unlikely to regulate long‐term energy balance. Baseline ghrelin concentrations are related to the degree of WL that can be achieved by active weight reduction.  相似文献   

16.
A longitudinal study consisting of 38 unrelated Macaca nemestrina and 16 Papio cynocephalus monkeys are investigated for palatal changes during the first two and a half years of life. The central problem is to ascertain whether there are any significant differences between the two genera regarding their relative growth rates. In order to examine this question, the amount of sexual dimorphism in absolute size was determined. There was no sex difference in palatal dimensions within the species but there were marked size differences between the groups. The relative growth rates present another story. There are no significant sex or intergeneric differences in growth rates. The genera are different in absolute size but they grow at about the same relative rates. These rates represent a decelerating curve in both genera.  相似文献   

17.
Field studies of two species of baboons suggest that Altmann's model of maternal time budgets (1980, Baboon Mothers and Infants, Cambridge, Massachusetts: Harvard University Press) provides a good qualitative but a poor quantitative fit to observed changes in the time that mothers spend feeding across infant age. We suggest that the poor quantitative fit might be explained by the fact that food quality varies across time, so that females are forced to feed for longer to gain the same nutrient intake when quality is poor. The hypothesis was tested with data from both gelada baboons,Theropithecus gelada , and Altmann's own baboons, Papio cynocephalus, with rainfall and ambient temperature as indices of vegetation nutritional quality. The results confirm that a three-factor model incorporating infant age, rainfall in the 2 preceding months and current ambient temperature provides a significantly improved fit to the observed data. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.  相似文献   

18.
The aim of this study was to investigate when adult distribution patterns are established in the barnacles Chthamalus stellatus and C. montagui. Adult ‘zones’ were identified by analysing field counts of both species at mid and upper shore heights. Monthly collections of cyprids, < 1 month old metamorphs and recruits (all metamorphosed individuals older than approximately 1 month) were made for C. stellatus and C. montagui in natural barnacle beds at six shores in SW Ireland. This was carried out over one year in 1996/1997, using a hierarchical sampling design. Abundance of total recruits (0-3 months old) was compared between adult zones after the main settlement season had ended. In addition, scales of variability in 0-3 month recruitment into adult zones were compared between the species at two scales: shores (1000s of metres) and sites within shores (10s of metres). Older recruits of each species, up to 11 months of age, were also compared between adult zones.The majority of settlement (measured as attached cyprids) occurred between August and October 1996. In October, there was no effect of adult zone on the abundance of total (0-3 month) recruitment up to that point in either species. Despite this homogeneity in recruitment between adult zones, significant spatial variation was found in 0-3 month recruits of both species at both of the scales examined. In C. stellatus the amount of variation associated with the larger scale (shore) was more than twice that of sites or of the residual variation (replicates within sites). 0-3 month recruitment in C. montagui was also most variable at the scale of shores but the residual variability (between replicates within site) was of similar magnitude to that of shores. Variability in 0-3 month C. montagui recruitment was relatively low at the scale of sites.There was a small but consistent input of recruits to adult zones over 9 months of the year, complicating the assessment of when adult patterns were set-up in these species. By June 1997, characteristic patterns of adult dominance had been established at all shores. Settlement had completely ceased by this time and individual barnacles were potentially 11 months old. Neither settlement nor early recruitment are significant in determining adult zonation patterns in these species. Instead, differential mortality patterns in individuals up to the age of 11 months are implicated in determining patterns of distribution of both species.  相似文献   

19.
Isozymes of lactate dehydrogenase extracted from heart, kidney, and liver of mink (Mustela vison Briss.) and Arctic fox (Alopex lagopus L.) during postnatal development were separated by agarose gel electrophoresis. Tissue-specific isozyme pattern of lactate dehydrogenase can be revealed at the age of one month, while the definitive pattern is formed at the age of four months. The isozyme patterns of lactate dehydrogenase in the studied tissues of mink and Arctic fox share the properties specific for animal species of various ecogenesis.  相似文献   

20.
Objective: The purpose of this study was to compare weight regain in a group of perimenopausal women (48.0 ± 4.4 years old), randomized to a 12‐month weight maintenance Internet intervention or to self‐directed weight maintenance after a 4‐month weight loss treatment. Methods and Procedures: After a 4‐month behavioral weight loss program, 135 women were randomized to either Internet or self‐directed groups. The Internet group (n = 66) used a website to gain information and complete logs concerning their weight, diet, and exercise progress over a 12‐month follow‐up. The 69 self‐directed women had no contact with study staff. All women were measured for weight and body composition, and diet intake, and were interviewed using the 7‐day physical activity questionnaires at baseline, 4 months, and 16 months. Results: At the end of the 12‐month follow‐up, the Internet and self‐directed groups had regained on average 0.4 ± 5.0 kg and 0.6 ± 4.0 kg, respectively (P = 0.5). In within‐group analyses, Internet diet‐log entries were correlated with follow‐up weight change (r = ?0.29; P < 0.05) and moderately with change in exercise energy expenditure (EEE; r = 0.44; P < 0.01). Follow‐up weight change was not correlated with change in dietary intake. Discussion: While significant weight loss was maintained over follow‐up by both groups of women, Internet use did not surpass self‐direction in helping to sustain weight loss. Among Internet users, Internet use was related to weight change and EEE.  相似文献   

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