Poor growth prior to early childhood: decreased health and life-span in the adult

Previous studies in animal populations have shown that stunted neural and thymolymphatic growth early in development may result in permanently impaired neural and immune function, decreased body growth, vertebral wedging, and decreased life-span. In the human adult, small vertebral neural canal (VNC) diameters may reflect early stunted neural and immune development and impaired function that leads to decreased health (inferred by greater vertebral wedging) and life-span in the adult. VNC, which complete their growth by early childhood (age 4), are markers of early development in adults. On the other hand, features following general body growth, such as height, weight (represented here by vertebral body height) continues to grow until young adulthood. They are less reliable, because they readily experience catch-up growth (even in chronically stressed populations) and, unlike VNC, may mask poor early growth. To test associations between early growth and adult health and life-span in humans, we measured 2,060 VNC, vertebral heights, vertebral wedging, nerve-root tunnel lengths, severity of vertebral osteophytosis, and ages at death in 90 adult (aged 15-55 years) prehistoric skeletons (950-1300 A.D.). Tibial lengths were also measured in a subsample (n = 30). Multivariate, bivariate, and nonparametric analyses showed that small VNC are significantly associated with greater vertebral wedging and decreased life-span (P less than 0.05-0.00001). VNC are independent of vertebral body heights and tibial lengths (general body growth). VNC, but not statural components, are useful in predicting adult health, presumably because they reflect neural and immune development and do not readily experience catch-up growth. Thus, longitudinal retrospective measures of early growth and adult health were systematically linked within individuals regardless of confounding factors operating over the 350-year time period. Since this research was completed, this model has repeatedly been independently confirmed in four living urban industrial populations. Longitudinal retrospective analysis was employed together with direct measures of VNC, neural and immune function. Together these results suggested that it may be essential to improve growth prior to early childhood in order to maximize adult health and life-span.     

Catch-up growth in Japanese quail (Coturnix Japonica): relationships with food intake, metabolic rate and sex

The effects of early environmental conditions can profoundly affect individual development and adult phenotype. In birds, limiting resources can affect growth as nestlings, but also fitness and survival as adults. Following periods of food restriction, individuals may accelerate development, undergoing a period of rapid “catch-up” growth, in an attempt to reach the appropriate size at adulthood. Previous studies of altricial birds have shown that catch-up growth can have negative consequences in adulthood, although this has not been explored in species with different developmental strategies. Here, we investigated the effects of resource limitation and the subsequent period of catch-up growth, on the morphological and metabolic phenotype of adult Japanese quail (Coturnix japonica), a species with a precocial developmental strategy. Because males and females differ in adult body size, we also test whether food restriction had sex-specific effects. Birds that underwent food restriction early in development had muscles of similar size and functional maturity, but lower adult body mass than controls. There was no evidence of sex-specific sensitivity of food restriction on adult body mass; however, there was evidence for body size. Females fed ad lib were larger than males fed ad lib, while females subjected to food restriction were of similar size to males. Adults that had previously experienced food restriction did not have an elevated metabolic rate, suggesting that in contrast to altricial nestlings, there was no metabolic carry-over effect of catch-up growth into adulthood. While Japanese quail can undergo accelerated growth after re-feeding, timing of food restriction may be important to adult size, particularly in females. However, greater developmental flexibility compared to altricial birds may contribute to the lack of metabolic carryover effects at adulthood.     

Lack of compensatory body growth in a high performance moose Alces alces population

Considerable work has been done on disentangling important factors determining early development in body size, yet our knowledge of the extent to which animals living under varying conditions can achieve catch-up growth for a bad start in life is limited. Here, we investigated how body mass at the age of 8 months influenced adult body mass in a moose Alces alces population living under excellent environmental conditions on the island of Vega in northern Norway. We also investigated if mother age and birth date effects on calf body mass persisted until adulthood. We show that neither males nor females were able to show compensatory growth before they reached adulthood, and that part of the variation in adult body mass may have been due to variation in mother age and date of birth. The pattern observed in males can be related to their growth strategy in relation to reproduction, while such results were not expected in females where size-dependent start of reproduction is likely to interact with body growth. We suggest that the good environmental conditions experienced on Vega led to females having small somatic costs of an early start of reproduction or that larger females were able to acquire more resources for growth than their smaller conspecifics. In both cases, females that postpone their first reproduction may not be able to achieve catch-up growth for their lower early body mass compared to females that start reproduction at an early age. Our results concur with previous studies indicating that compensatory growth is weak in moose, increasing the likelihood that variation in life history characters are also transferred between generations.     

Reproductive constraints,not environmental conditions,shape the ontogeny of sex‐specific mass–size allometry in roe deer

In polygynous mammals, sex‐specific patterns of body growth are linked to divergent selection pressures on male and female body size, resulting in sexual dimorphism (SD). For males, reproductive success is generally linked to body size, hence, males should prioritise early growth. For females, reproductive success is linked to resource availability, so they may adopt a more conservative growth tactic. Using longitudinal monitoring of known‐age animals in two contrasting populations and an allometric approach to disentangle the relative contribution of structural size and physiological condition to SD, we addressed these issues in the weakly polygynous roe deer. Despite very different environmental conditions, we found remarkably similar patterns in the two populations in the mass–size allometric relationship at each life history stage, suggesting that relative allocation to structural size and physiological condition is highly constrained. SD in structural size (indexed by hind foot length) involved sex‐specific growth trajectories governed by a single mass–size allometric relationship during the juvenile stage, such that males were both bigger and heavier than females. In contrast, SD in physiological condition (indexed by the allometric relationship between body mass and hind foot length, expressed as body mass for a given body size) developed markedly during the sub‐adult stage in relation to sex differences in the timing of first reproduction. Among adults, males were heavier for a given size than females, suggesting that, relative to females, males express a capital breeder tactic, accumulating fat reserves to offset reproductive costs. By the senescent stage, SD in physiological condition had disappeared, with both sexes governed by a single allometric relationship, suggesting more rapid senescence in males than females. Individuals born into poor cohorts were generally lighter for a given size, indicating growth priority for skeletal size over physiological condition in both sexes. However, sex differences in cohort effects among sub‐adults resulted in lower size‐specific SD in poor cohorts, indicating that body condition of sub‐adult females is buffered against environmental harshness. We conclude that sex‐differences in reproductive tactics impose constraints on the ontogeny of SD in roe deer, leading to sex‐specific trajectories in structural size and physiological condition.     

Paleoepidemiology of a central California prehistoric population from Ca-Ala-329: II. Degenerative disease

Degenerative lesions are scored and frequencies of involvement are computed for a skeletal collection from Ca-Ala-329, a prehistoric site on the southeastern side of San Francisco Bay, dating from 500 A.D. up to European contact. A large earthmound site, excavations conducted there by San Jose State University retrieved close to 300 burials. For this epidemiological analysis, reasonably complete and aged skeletons representing 77 adult females and 90 adult males are available. Degenerative changes are scored macroscopically in an ordinal fashion for the large fibro-cartilagenous joints between adjacent vertebral bodies (vertebral osteophytosis) as well as the small apophyseal articulations of the spine. In addition, in the peripheral skeleton degenerative changes are scored in the temporo-mandibular, shoulder, elbow, hip, and knee joints as well as the small articulations of the hands and feet. The most common degenerative changes in the spine are seen between the vertebral bodies of the lower lumbar region. In the peripheral skeleton the highest involvement of degenerative disease is seen in the hands and feet. Compared to other relevant osteological samples, this group of hunting-gathering California Indians shows more degenerative changes than settled agriculturists (from Pecos Pueblo, New Mexico) but substantially less frequent involvement than in arctic hunters (Alaskan Eskimos).     

Biocultural analysis of sex differences in mortality profiles and stress levels in the late medieval population from Nova Raca, Croatia

Human skeletal remains of 104 individuals from the late medieval (14th-18th century) Nova Raca cemetery, in continental Croatia, are described. Historic data from the parish Book of the Dead, relevant to a period in the early 19th century, suggest that females may have been under greater stress than males. To test this hypothesis, the skeletal material is analyzed for the presence and distribution of enamel hypoplasias and cribra orbitalia. Observations are also made on the presence and pattern of dental disease, skeletal infection, trauma, osteoarthritis, vertebral degenerative changes, and Schmorl's depression frequencies. The mortuary sample, consisting of 36 subadults and 68 adults, exhibits underrepresentation of subadults, and differential adult male/female mortality profiles. Peak female mortality is between 21-25 years, compared to peak male mortality between 31-35 years. Average adult female age at death is 29.9 years, compared to 34.1 years in adult males. Significant sex differences are present in the frequencies of enamel hypoplasia. Adult females have higher frequencies of hypoplastic teeth, and a larger number of defects in the teeth affected than in males. Subadults in the series also exhibit higher frequencies of hypoplastic teeth, and a larger number of defects in the teeth affected than in adults, documenting a relationship between enamel hypoplasia-causing stress events and reduced life expectancy. Significant sex differences are also present in dental pathology frequencies, possibly reflecting differences in resource access. Sex differences in vertebral osteoarthritis and Schmorl's depression frequencies may reflect differential activity patterns.     

Sex differences in compensatory and catch-up growth in the mosquitofish Gambusia holbrooki

In many taxa, temporary nutritional shortage early in development can favour compensatory strategies that include elevated growth (‘compensatory growth’) and/or extension of the usual period of development (‘catch-up growth’) once conditions improve. The net gains from each strategy depend on the extent to which larger body size increases fitness relative to associated costs (e.g. long-term effects on adult performance, or a greater risk of juvenile mortality). These costs and benefits are likely to differ between the sexes due to sex-specific selection. We documented the responses of male and female mosquitofish (Gambusia holbrooki) to 3 weeks of low food availability (7–28 days old) that restricted subsequent growth and morphology compared to control fish continuously reared on a high food diet (N = 635 fish total). Neither sex elevated their growth rate immediately after being returned to a normal diet compared to control fish. When measured over the entire period until maturation, however, females showed compensatory growth. Males did not. Both sexes also exhibited catch-up growth but the delay until maturation was significantly longer for males. Despite early growth restriction, both sexes eventually matured at almost the same size as control fish, although males had a significantly smaller gonopodium (a sexually selected trait) than that of control males. Reasons for these sex differences are discussed.     

A quantitative study of morphological and histological changes in the skeleton of Salmo salar during its anadromous migration

A quantitative study of morphological and histological changes in the skeleton (cranial bones and vertebrae) of adult Atlantic salmon Salmo salar during its anadromous migration was performed in order to specify various aspects of its skeletal biology in relationship to this migration. At the beginning of the ascent, there was no morphological difference in the cranial bones between males and females. As the spawning season approached, males showed marked secondary sexual characters particularly allometric breeding growth of some bones of the skull. The histological analysis of the vertebral bone tissue along the vertebral axis showed that bone compacity and number of trabeculae vary depending on their localization on the vertebral axis. Moreover, bone compacity decreased significantly with the sexual maturation of the fish whereas the number of trabeculae grew in both sexes. Thus, the vertebrae (like scales) represent an important source of calcium and other elements during anadromous migration in Atlantic salmon.     

Life stress on the Roman limes in continental Croatia

The purpose of the paper is to analyze and compare the demographic profiles and disease frequencies between a skeletal series from Zmajevac, a settlement on the Danubian limes, and a composite «non-limes» skeletal series consisting of human osteological remains from three large urban settlements to the west of the limes; roman Mursa (modern Osijek), Cibalae (Vinkovci) and Certissia (Štrbinci). To determine if life stresses were different in settlements on the limes the age and sex distribution in Zmajevac was compared to the composite «non-limes» series. All skeletons were also analyzed for the presence of dental pathology, dental enamel hypoplasia, cribra orbitalia, trauma, and physical stress.

Data collected from the skeletal series show that, with the exception of some indicators of physical stress, no significant differences in quality of life is evident. Both series are characterized by an underrepresentation of subadults from the youngest age category and by similar average adult male and female ages at death. In Zmajevac the average ages at death for adult males and females were 40.0 and 39.0 years respectively, in the composite «non-limes» series 37.4 years for both males and females. The frequencies of dental disease, subadult stress indicators, and trauma are similar in both series. The only consistent difference between the two series is noted in the frequencies of skeletal markers of physical stress, in particular the frequencies of vertebral osteoarthritis and Schmorl's defects. Total male and total female vertebral osteoarthritis frequencies in the two series are significantly different, as is the difference in total male frequencies of Schmorl's defects. Young adult males in the Zmajevac series seem to have been experiencing particularly heavy physical strain on the vertebral column. They exhibit significantly higher frequencies of both vertebral osteoarthritis and Schmorl's defects than young adult males from the composite non-limes series.     

Palaeolithic Grandmothers? Life History Theory and Early Homo

The acknowledged success of early Homo has generally been thought to reflect male-dominated provisioning and associated patterns of co-operative social organization; recently, however, such conclusions have been challenged with the argument that post-menopausal females, instead, played a significant role in early human subsistence activities; males, it has been proposed, had a very minor role in food acquisition in early Homo . The fossil record, however, indicates minimal old-age survivorship of either sex and heavy young adult mortality, a pattern which is also seen in larger prehistoric and ethnographic samples. Heavy young adult mortality, when combined with characteristically slow maturation, represents a paradox which humans have solved through new reproductive strategies (early weaning and alloparenting) and new life history stages (childhood and adolescence). Stone tools, when used to acquire marrow and brain tissue to feed needful youngsters, may also have been among the strategies developed in response to frequent early parental death.     

白藜芦醇对成年期追赶生长大鼠体成分的影响及机制

目的:观察白藜芦醇对成年期追赶生长大鼠体成分的影响及可能机制。方法:8周龄雄性 SD 大鼠分为6组(共2个时间点),即4周时间点3组:正常饮食4周 (NC4)组、热卡限制4周(R4)组,热卡限制同时白藜芦醇治疗(R4E)组;12周时间点3组:正常饮食12周(NC12)组,追赶生长(CUG)组,追赶生长白藜芦醇治疗(CUGE)组。每组含6只大鼠,白藜芦醇用生理盐水配制成一定浓度悬浊液,按100 mg/(kg·d)剂量予实验动物灌胃治疗。实验第4周、12周检测体重、躯干和全身的肌肉及脂肪含量、躯干与全身脂肪比例,实验第12周检测骨骼肌与附睾脂肪组织SIRT1的表达,附睾脂肪组织PPARγ的表达。结果:与NC12组相比,CUG组躯干及全身的脂肪含量、躯干与全身脂肪比例、附睾脂肪组织PPARγ的表达均明显升高(P＜0.05),肌肉含量、骨骼肌与附睾脂肪组织SIRT1的表达显著降低(P＜0.05或P＜0.01);与CUG组相比,经白藜芦醇干预后的CUGE组全身的脂肪含量、躯干与全身脂肪比例、附睾脂肪组织PPARγ的表达均明显降低(P＜0.05),肌肉含量、骨骼肌与附睾脂肪组织SIRT1的表达较CUG组显著提高(P＜0.05)。结论:白藜芦醇降低成年期追赶生长大鼠体脂含量,增加肌肉含量,改善腹部脂肪堆积,其机制可能与增加骨骼肌及内脏脂肪组织SIRT1表达,抑制内脏脂肪PPARγ的表达有关。     

Longitudinal analysis of length growth in the chimpanzee (Pan troglodytes)

The adolescent growth spurt in linear dimension in humans is considered to be unique among mammals, but few comparative studies have been done, even on chimpanzees. Growth of the summed length of crown to rump, thigh, and leg was studied longitudinally in 12 chimpanzees. We took body weight growth and reproductive maturation into consideration. Reproductive maturation was monitored by the swelling of sexual skin and menarche in females, and by testicular development in males. We applied two relationships found in humans between body length growth and the environment to the chimpanzees. The first relationship was the robustness of the growth spurt, meaning that the spurt is absent only in individuals under the most severe environmental pressure. Subjects maturing in a favorable or even mediocre environment are anticipated to show the growth spurt. The second relationship was catch-up growth, where, when the environment is ameliorated, growth may be accelerated to attain the target size. Catch-up growth at the end of the juvenile period may mimic the adolescent growth spurt. Results showed that subjects living under favorable conditions did not exhibit a growth spurt, and that it was only the subjects who had delayed growth in the juvenile period that showed a spurt in adolescence, the period when reproductive maturation occurred. Although we have concluded that chimpanzees do not have an adolescent growth spurt, except in cases of catch-up growth, this does not mean that they have a different growth pattern from that of humans. The absence of a growth spurt may be associated with adaptations to chimpanzee patrilineal society, where adolescent males are incorporated into the adult hierarchy at a low rank.     

Seasonal variation of mass, condition and gonadosomatic index in fourhorn sculpin (Myoxocephalus quadricornis) with normal and malformed vertebrae in the Gulf of Bothnia

It may be expected that vertehral anomaties would reduer the viability and reproductive success of fish. In the present study. the relationship of vertebral defects to body mass. Iength, age, condition, gonadosomatic index and growth in fourhorn sculpin, Myoxocephalus quadricornis , in the Gulf of Bothnia was studied. There were no differences in growth between normal and defective lish, for either males or females. While normal and defectives males were similar in age and length. defective females were older and longer than normal females. Defective males and females had a significantly greater somatic mass that normal fish. However defective females may be later than in normal fish. Hence, vertebral defects do not necessarly reduce the reproductive potential of fourhorn sculpin.     

Association between postnatal catch-up growth and obesity in childhood: prospective cohort study

ObjectiveTo identify predictors of postnatal catch-up growth from birth to two years and its relation to size and obesity at five years.DesignRegional prospective cohort study.SettingAvon longitudinal study of pregnancy and childhood, United Kingdom.Subjects848 full term singletons from a 10% random sample of the Avon longitudinal study of pregnancy and childhood.ResultsSize at birth was representative of the national reference. Overall, 30.7% (260 of 848) of infants showed a gain in SD score for weight greater than 0.67 SD scores between zero and two years, indicating clinically significant catch-up growth. These children had lower weight, length, and ponderal index at birth than other children, and were more often from primiparous pregnancies. They also had taller fathers than other children, and their mothers had lower birth weights and were more likely to smoke during pregnancy. Children who showed catch-up growth between zero and two years were heavier, taller, and fatter (body mass index, percentage body fat, and waist circumference) at five years than other children.ConclusionsIn this contemporary well nourished cohort, catch-up growth was predicted by factors relating to intrauterine restraint of fetal growth. Children who showed catch-up growth between zero and two years were fatter and had more central fat distribution at five years than other children. Mechanisms that signal and regulate early catch-up growth in the postnatal period may influence associations between small size at birth and risks for disease in adulthood.     

Annual survival of Gurney's Sugarbird,Promerops gurneyi

Seasonal variation in body mass and wing length, and the onset and duration of primary moult, were investigated for Chestnut Weavers from northern Namibia. Body mass of adult males was 31.2g (SD 2.6), and adult females weighed 27.4g (SD 1.9). Body mass declined from March to April, and started increasing after August (i.e. near the end of moult) in males and females. Wing length in adult males with new primaries (Oct–Feb) was 80.7mm (SD 2.7) and for adult females (Oct–Feb) 76.8mm (SD 2.6). For both sexes wing length declined during and after the breeding season, due to extensive feather wear. Adult males started primary moult significantly earlier than females (9 April vs 30 April) and moult lasted longer (206 days vs 189 days). The peak summer rainfall and the start of primary moult was earliest in 2000 and latest in 2004 for males and females. Individual primary feathers took 11–18 days to grow.     

Early constraints in sexual dimorphism: survival benefits of feminized phenotypes

Sexual dimorphism (SD) has evolved in response to selection pressures that differ between sexes. Since such pressures change across an individual's life, SD may vary within age classes. Yet, little is known about how selection on early phenotypes may drive the final SD observed in adults. In many dimorphic species, juveniles resemble adult females rather than adult males, meaning that out of the selective pressures established by sexual selection feminized phenotypes may be adaptive. If true, fitness benefits of early female‐like phenotypes may constrain the expression of male phenotypes in adulthood. Using the common kestrel Falco tinnunculus as a study model, we evaluated the fitness advantages of expressing more feminized phenotypes at youth. Although more similar to adult females than to adult males, common kestrel fledglings are still sexually dimorphic in size and coloration. Integrating morphological and chromatic variables, we analysed the phenotypic divergence between sexes as a measure of how much each individual looks like the sex to which it belongs (phenotypic sexual resemblance, PSR). We then tested the fitness benefits associated with PSR by means of the probability of recruitment in the population. We found a significant interaction between PSR and sex, showing that in both sexes more feminized phenotypes recruited more into the population than less feminized phenotypes. Moreover, males showed lower PSR than females and a higher proportion of incorrect sex classifications. These findings suggest that the mechanisms in males devoted to resembling female phenotypes in youth, due to a trend to increase fitness through more feminized phenotypes, may provide a mechanism to constrain the SD in adulthood.     

Degenerative spondylolisthesis in ancient and historic skeletons from New Mexico Pueblo sites.

The objective of this study was to identify the presence of degenerative spondylolisthesis in adult Native American skeletons recovered from prehistoric and historic Pueblo sites in New Mexico. The vertebral columns of 491 individuals that were complete enough to allow the necessary observations produced 64 cases, with a total of 74 affected levels. The L5-S1 level was affected most frequently (78%), in contrast to clinical and anatomical studies where the L4-L5 level was usually affected (80%). Age and sex were found to be important factors, with the condition limited to middle and old adults, and occurring in females over males at a ratio of approximately 5:1. Olisthesis was shown to occur only in association with severe osteoarthritis of the zygapophysial joints, but severe osteoarthritis did not always result in olisthesis, particularly in males. Parallel or convergent inferior articular processes were found to increase in frequency in the presence of olisthesis, apparently resulting from degenerative remodeling that produced the olisthesis. The data also suggest that individuals with cranial border shifting in the column may be especially prone to olisthesis. Degenerative olisthesis was also observed in the cervical region.     

Effects of protein deficient diets on the developmental toxicity of inorganic arsenic in mice

BACKGROUND: Inorganic arsenic, when given by injection to pregnant laboratory animals (mice, rats, hamsters), has been shown to induce malformations. Arsenic methylation may be a detoxification step, and diets deficient in protein are a poor source of methyl donors and may possibly result in impaired arsenic methylation. Human health effects from chronic arsenic exposure have been reported mainly in populations with low socioeconomic status. Individuals in such populations are likely to suffer from malnutrition, which can compromise embryonic/fetal development and diminish arsenic methylating capacity. We sought to determine if dietary protein deficiency affects the developmental toxicity of inorganic arsenic. METHODS: Mated females were randomly assigned to one of 12 treatment groups. Experimental groups received either AsIII or AsV i.p. on Gestation Day 8 (GD 8, plug=GD 0) and were maintained on a 5%, 10%, or 20% protein custom mixed diet from GD 1 until sacrifice. Controls received the custom diets alone, were given AsIII or AsV i.p. on GD 8 with Teklad LM-485 rodent diet, or were fed the LM-485 diet alone. Test females were sacrificed on GD 17, and their litters were examined for mortality and developmental defects. RESULTS: Arsenic plus dietary protein deficiency decreased maternal weight gain and increased the incidences of exencephaly, ablepharia, and skeletal defects, such as malformed vertebral centra, fused ribs, and abnormal sternebrae (bipartite, rudimentary, or unossified). CONCLUSIONS: These results demonstrate that dietary protein deficiency enhances the developmental toxicity of inorganic arsenic, possibly by impairment of arsenic methylation.     

Correlation of kidney weight and volume and selected skeletal parameters to sex in the adult rhesus monkey (Macaca mulatta)

This report outlines a comparison of renal weight and volume and selected skeletal parameters to sex in 22 adult male and 156 adult female rhesus macaques. Means and standard deviations for kidney weight and volume, body weight, and radiographic measurements for both males and females are reported. Ninety-five percent confidence intervals and P-values for the mean differences between the sexes for these parameters were also compiled. Male monkeys were larger, but had kidneys of similar size to those of the females. Joint distributions of the radiographic measurements of the first lumbar vertebra and the skull showed that males were larger in both measurements. The distributions of these parameters were clearly separate in males and females, while joint distributions of kidney weight and volume for males and females overlapped almost completely. We found that, regardless of age, sex, weight, or skeletal size, all normal adult rhesus monkeys generally have similar-sized kidneys.