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灵长类中根据牙齿的萌出情况和换齿序来确定年龄的研究国内较少。曾中兴等1965在“猕猴精巢发育的研究”中顺带谈到换齿序和年龄的关系,1980年又在“猕猴乳齿的发育”文章中提到乳齿发育与年龄关系。国外研究较多,如赫尔曼(Hurme)、詹姆斯(James)等,对猕猴的出齿序和年龄关系均有论述。肯尼(Kenney),又将前几位学者的工作进行了综述并有所推进。金丝猴(Rhinopithecus roxellanae)的出齿序和年龄的关系,则尚未见有报道。本文目的就是根据我国珍稀动物金丝猴的资料(牙齿: 相似文献
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对在湖北长阳县深潭湾崖葬墓出土的青铜时代人类乳齿形态特征的观察研究显示在人类恒齿出现的大多数具有种族识别价值的形态特征在乳齿有相等程度的表现,其中部分特征的出现率和表现程度高于恒齿。与其他地区人群相比,长阳青铜时代人类乳齿特征在总体上与东北亚人类具有的“中国型牙齿”特征接近。同时,在个别牙齿特征上呈现出南亚蒙古人种的特点。作者对产生这种现象的原因进行了分析。本文还就长阳青铜时代人类乳齿测量数据的表现特点进行了探讨。 相似文献
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灵长类恒齿的出牙顺序 总被引:1,自引:0,他引:1
灵长类学家舒尔茨(A.H.Schultz)曾提出灵长类中由低级到高级的各种动物恒齿出牙顺序的差别是有规律地发展的。他提出了这样的顺序: I 代表门齿,C 代表犬齿,P 代表前臼齿,M 代表臼齿。每一字母右下角的数字代表各该齿的顺次,如 M_1代表第一臼齿。单线的字母代表在原来乳齿齿列后面新增加的恒齿;双线的字母代表替换乳齿的恒齿。括号内的各齿是出牙先后次序可能颠倒的,放在前面的则是通常长出较早的。 相似文献
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笔者于1997年对中华山蝠(Nyctalus velutinus)牙齿的脱换模式进行了研究。共观察幼蝠200只次。中华山蝠初生仔共有22枚乳齿,齿式为2.1.2.0/3.1.2.0,各乳齿略向舌侧倾斜,除乳前臼齿齿冠不分叉外,其余乳齿齿冠均分为三叶。4d龄开始换齿,31d龄左右脱换完毕。乳齿的脱落顺序是:上颌,PM2→PM1→C1→I1→I2;下颌,I1→PM2.I2→I3→PM1→C1;恒齿萌生的顺序为:上颌,M1→PM2.C1→M2→PM1.M3→I1→I2,下颌,M1→I1.PM2→I2.M2→I3.PM1→C1→M3。 相似文献
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为了研究亚洲疣猴牙齿形态与功能适应性之间的关系,建立异速生长公式比较分析生活于同一大陆的猕猴。主成份分析用来分析来自异速生长公式的残差。结果表明:疣猴出乎意料地展示了比猕猴更小的门齿。导致此结果的可能原因是:疣猴与猕猴之间的食物差异性。但是,这种差异小于亚-非大陆种类。也就是说,在过去的500万年左右的时间里,生活于同一大陆的疣猴和猕猴已经产生了一些对环境和食性的趋同性。当每一个疣猴属分别与猕猴进行比较时,它们之间的差异性揭示了地理分布的差异。金丝猴(Rhinopithecus)和长尾叶猴(Semnopithecus)具有比其他疣猴发达的臼齿。欧氏距离的结果说明疣猴和猕猴牙齿的差异性揭示了它们在系统发育方面的关系。 相似文献
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对出自禄丰石灰坝的26个禄丰古猿下颌齿列的246枚恒齿进行了观察研究,发现禄丰古猿具有普遍的带状釉质发育不全(LEH)现象,个体LEH比例为100%,恒齿LEH比例为85%。乳齿几乎没有LEH现象,第一恒臼齿的LEH比例也很低仅57%。根据牙齿萌出顺序及现代大猿的牙齿发育年龄特征,作者推断2—3岁之前的幼儿古猿很少出现釉质发育不全现象,这可能与母体的营养关照有关。禄丰古猿的LEH的发生频率具有明显的季节性,结合中新世晚期气候变化特征、古猿的生态环境、生活习性及食性特征分析,作者推测:季节性营养不良可能是造成禄丰古猿釉质发育不全的主要原因。 相似文献
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Effects of age and season on the developmental capacity of oocytes from unstimulated and FSH-stimulated rhesus monkeys were examined. Immature cumulus-oocyte complexes were matured in vitro in modified CMRL-1066 medium containing 20% bovine calf serum and subjected to in vitro fertilization followed by embryo culture. After fertilization, ova from unstimulated prepubertal monkeys displayed lower development to morula (4%) than those from unstimulated adult females (18% in breeding season and 22% in nonbreeding season). No developmental difference was found between ova from unstimulated adult monkeys in breeding and nonbreeding seasons. However, ova from FSH-primed prepubertal monkeys displayed greater development to blastocyst stage (54%) than those from adult monkeys in the breeding season (16%) and nonbreeding season (0%); and ova from FSH-primed adult females in the breeding season had significantly (P < 0.05) greater developmental competence than those obtained in the nonbreeding season (> or = morula stage, 54% vs. 3%; blastocyst stage, 16% vs. 0%). These data indicate that 1) rhesus monkey oocytes acquire developmental competence in a donor age-dependent manner, and 2) animal age and breeding season modulate the effect of FSH on oocyte developmental competence in the rhesus monkey. 相似文献
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Two pairs of laboratory born rhesus monkeys gave birth to healthy young at an unusually early age, indicating that sexual maturity for this species is possible at a much earlier age than had been previously reported.Supported by MH22253 toG. Mitchell, HD04335 toL. Chapman, RR00169 to California Primate Research Center and MH54546-01 toTerry Maple. 相似文献
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Andrade MC Ribeiro CT Silva VF Molinaro EM Gonçalves MA Marques MA Cabello PH Leite JP 《Memórias do Instituto Oswaldo Cruz》2004,99(6):581-589
Physiological parameters of laboratory animals used for biomedical research is crucial for following several experimental procedures. With the intent to establish baseline biologic parameters for non-human primates held in closed colonies, hematological and morphometric data of captive monkeys were determined. Data of clinically healthy rhesus macaques (Macaca mulatta), cynomolgus monkeys (Macaca fascicularis), and squirrel monkeys (Saimiri sciureus) were collected over a period of five years. Animals were separated according to sex and divided into five age groups. Hematological data were compared with those in the literature by Student's t test. Discrepancies with significance levels of 0.1, 1 or 5% were found in the hematological studies. Growth curves showed that the sexual dimorphism of rhesus monkeys appeared at an age of four years. In earlier ages, the differences between sexes could not be distinguished (p < 0.05). Sexual dimorphism in both squirrel monkeys and cynomolgus monkeys occurred at an age of about 32 months. Data presented in this paper could be useful for comparative studies using primates under similar conditions. 相似文献
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The sexual initiating behavior of male and female cynomolgus monkeys (Macaca fascicularis) observed during standard laboratory tests is reviewed and compared with that of rhesus monkeys (M. mulatta) observed under identical conditions. Species differences in sexual behavior are related here to differences in habitat, sexual dimorphism, and the dominance gradient between the sexes. Compared with rhesus monkeys, cynomolgus monkeys appear to be more arboreal, less sexually dimorphic, and have a smaller dominance gradient between the sexes. They exhibit a facultative single-mount copulatory pattern rather than the serial mount pattern of the rhesus monkey. Female cynomolgus monkeys are less dominated than rhesus females by their male partners. Direct aggression between mates is more frequent and redirected aggression occurs less often than in rhesus monkeys. These behavioral differences affect the interpretation of changes in initiation rates that occur (1) during the menstrual cycle, (2) when females are ovariectomized and given hormone replacement treatments, and (3) when males are castrated and treated with androgens. We conclude that estradiol in the female and testosterone in the male increase the sexual motivation of both the treated and the untreated partner. Valid interpretations of changes in initiation rates depend on accurate and exclusive definitions of behavior and on a consideration of the behavioral context in which they are made. 相似文献
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The effects of prostaglandin (PG)F2alpha and PGF2alpha, 1-15 lactone were compared in luteal phase, non-pregnant and in early pregnant rhesus monkeys. Animals treated with either PG after pretreatment with human chorionic gonadotropin (hCG) had peripheral plasma progesterone concentrations that were not statistically different from those in animals treated with hCG and vehicle. However, menstrual cycle lengths in monkeys treated with PGF2alpha, 1-15 lactone were significantly (P less than 0.02) shorter than those in vehicle treated animals. In the absence of hCG pretreatment, plasma progesterone concentrations were significantly (P less than 0.008) lower by the second day after the initial treatment with either PGF2alpha or PGF2alpha, 1-15 lactone than in vehicle treated monkeys. Menstrual cycle lengths in monkeys treated with either PG were significantly (P less than 0.04) shorter than those in animals treated with vehicle. There were no changes in plasma progesterone concentrations in early pregnant monkeys treated with PGF2alpha, and pregnancy was not interrupted. In contrast, plasma progesterone declined and pregnancy was terminated in 5 of 6 early pregnant monkeys treated with PGF2alpha, 1-15 lactone. These data indicate that PGF2alpha, 1-15 lactone decreases menstrual cycle lengths in non-pregnant rhesus monkeys. More importantly, PGF2alpha, 1-15 lactone terminates early pregnancy in the monkey at a dose which is less than an ineffective dose of PGF2alpha. 相似文献
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This study assessed the natural killer (NK) cell activity profile during Plasmodium cynomolgi infection in rhesus monkeys. There was a significant decrease in the NK cell activity in the peripheral blood leukocytes of infected monkeys during the early, ascending phase of infection. However, as the parasite load decreased, NK cell activity returned to normal levels. This could be correlated with the peak increase in lymphocyte counts. This indicated that a decrease in NK cell activity observed at an earlier stage during an active P. vivax malarial infection was a temporary phenomenon. 相似文献
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Abstract This study assessed the natural killer (NK) cell activity profile during Plasmodium cynomologi infection in rhesus monkeys. There was a significant decrease in the NK cell activity in the peripheral blood leukocytes of infected monkeys during the early, asending phase of infection. However, as the parasite load decreased, NK cell activity returned to normal levels. This could be correlated with the peak increase in lymphocyte counts. This indicated that a decrease in NK cell activity observed at an earlier stage during an active P. vivax malarial infection was a temporary phenomenon. 相似文献
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Yang S He X Hildebrandt TB Jewgenow K Goeritz F Tang X Zhou Q Ji W 《Theriogenology》2007,67(6):1194-1201
The objective was to study the effects of dose of recombinant human follicular stimulating hormone (rhFSH) for ovarian stimulation in rhesus monkeys. Nineteen pubertal and 109 adult female rhesus monkeys were given 37.5, 18, or 9 IU of rhFSH twice-daily for 8 days (total of 600, 300, or 150 IU of rhFSH per cycle, respectively; designated Regimens 1, 2 and 3). Ovarian responses were assessed with ultrasonography, serum concentrations of E2 and FSH, and by in vitro developmental potential (following IVF) of retrieved oocytes. Regimen 1 had more monkeys with very large follicles (diameter>8 mm) than Regimen 2 (P<0.05), which impaired development potential. However, there were no differences between Regimens 1 and 2 in oocyte recovery, whereas Regimen 3 did not elicit superovulation. The developmental potential of embryos obtained from Regimen 2 was higher than that of Regimen 1, as determined by culture to the blastocyst stage in vitro (proportion of blastocysts relative to collected MII oocytes was 55.8% versus 36.8% in pubertal and 63.8% versus 44.2% in adult monkeys; P<0.05 for each), and the results of embryo transfer from Regimen 2 were acceptable. In conclusion, we inferred that the optimal rhFSH dose for ovarian stimulation in rhesus monkeys was a total of 300 IU; this dose should be efficacious for ovarian stimulation as the quality or recovered oocytes was higher and the risk of overstimulation was reduced. 相似文献
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The concentrations of phosphorylcreatine (PCr), adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), inorganic phosphate (Pi), pyruvate and lactate were determined in freeze-clamped fast muscle samples from Oreochromis alcalicus grahami a fish adapted to extreme alkalinity (∼ pH 10·0) and high temperatures (Lake Magadi, Kenya). Specimens were analysed from both geothermally heated hotsprings (35–37°C) and from isolated cool pools (28°C) and from stocks acclimated to 20°C in the laboratory. The ratios of (ATP)/(ADP) and (ATP)/(ADP) (Pi) decreased with increasing body temperature consistent with an increase in glycolysis and tissue respiration rates, respectively. The apparent equilibrium constant of creatine kinase (KCK ), (creatine) (ATP)/(phosphorylcreatine) (ADP) was found to decrease with increasing temperature: 20·2 (20°C), 13·9 (28°C), 8·0 (37°C). A near constant muscle and blood pH (or slight increase in alkalinity with higher temperatures) was found regardless of body temperature (Blood pH 7·64, 7·74, muscle pH 7·27, 7·51 at 20°C and 35°C, respectively). These results are consistent with an unusual pattern of acid-base regulation in this species. 相似文献