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1.
The high proportion of human infant fat is hypothesized to protect infant brains by mobilizing against growth disturbances caused by acute nutritional and pathogen stress during weaning. However, individuals who experience chronic nutritional stress have been shown to store fat rather than mobilize fat stores, although this has not been demonstrated during infancy. This study investigated the relationship between fat development, diet, and nutritional status among 239 breastfeeding Ariaal infants, a group of settled pastoralists who experience both acute and chronic nutritional stress residing in Marsabit District, Kenya. This study had three goals: 1) To investigate the pattern of fat accumulation among Ariaal infants compared with a reference population; 2) to explore the relationship between chronic nutritional stress and fat deposits; and 3) to determine the relationship between traditional weaning foods, particularly cow's milk, and infant's fat. Infants, particularly infants experiencing chronic nutritional stress, were found to accumulate fat deposits in a manner that suggests reduced oxidation of fat stores. Infant upper arm fat area significantly increases with age over the weaning period compared with reference populations, who show a decline in body fat. Chronically undernourished infants were particularly likely to have increased levels of upper arm fat compared with normal infants or acutely undernourished infants. In addition, infants who consume cow's milk are significantly fatter than those that do not. These results suggest that Ariaal infants have both physiological and cultural mechanisms for fat storage in the face of their nutritionally stressed environment. Am J Phys Anthropol 153:286–296, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

2.
Early-life conditions shape childhood growth and are affected by urbanization and the nutritional transition. To investigate how early-life conditions (across the “first” and “second” 1000 days) are associated with rural and urban children's nutritional status, we analyzed anthropometric data from Maya children in Yucatan, Mexico. We collected weight, height and triceps skinfold measures, then computed body mass and fat mass indices (BMI/FMI), in a cross-sectional sample of 6-year-olds (urban n = 72, rural n = 66). Demographic, socioeconomic and early-life variables (birthweight/mode, rural/urban residence, household crowding) were collected by maternal interview. We statistically analyzed rural-urban differences in demographic, socioeconomic, early-life, and anthropometric variables, then created linear mixed models to evaluate associations between early-life variables and child anthropometric outcomes. Two-way interactions were tested between early-life variables and child sex, and between early-life variables and rural-urban residence. Results showed that rural children were shorter-statured, with lower overweight/obesity and cesarean delivery rates, compared to urban children. Household crowding was a negative predictor of anthropometric outcomes; the strongest effect was in boys and in urban children. Birthweight positively predicted anthropometric outcomes, especially weight/BMI. Birth mode was positively (not statistically) associated with any anthropometric outcome. Cesarean delivery was more common in boys than in girls, and predicted increased height in urban boys. In conclusion, urbanization and household crowding were the most powerful predictors of Maya 6-year-old anthropometry. The negative effects of crowding may disproportionately affect Maya boys versus girls and urban versus rural children. Early-life conditions shape Maya children's nutritional status both in the “first” and “second” 1000 days.  相似文献   

3.
The common bacterial toxins hypothesis of sudden infant death syndrome (SIDS) is that nasopharyngeal bacterial toxins can trigger events leading to death in infants with absent/low levels of antibody that can neutralise the toxins. The aim of this study was to investigate nasopharyngeal carriage of Staphylococcus aureus and determine levels of immunity in the first year of life to toxic shock syndrome toxin (TSST-1) and staphylococcal enterotoxin C (SEC). Both toxins have been implicated in SIDS cases. Seventy-three mothers and their infants (39 males and 34 females) were enrolled onto the study. The infants had birth dates spread evenly throughout the year. In infants, S. aureus carriage decreased significantly with age (P<0.001). Between 40% and 50% of infants were colonised with S. aureus in the first three months of life and 49% of the isolates produced one or both of the staphylococcal toxins. There was a significant correlation between nasopharyngeal carriage of S. aureus in mothers and infants in the three months following the birth (P<0.001). Carriage of S. aureus in infants and their mothers was not significantly associated with levels of antibody to TSST-1 or SEC in cord blood, adult saliva or breast milk. Infants colonised by S. aureus had higher levels of salivary IgA to TSST-1 than infants who were culture negative. Analysis of cord blood samples by a quantitative ELISA detected IgG bound to TSST-1 and SEC in 95.5% and 91.8% of cases respectively. There was a marked variation in levels of maternal IgG to both TSST-1 and SEC among cord blood samples. Maternal age, birth weight, and seasonality significantly affected the levels of IgG binding to TSST-1 or SEC. Analysis of infant saliva samples detected IgA to TSST-1 and SEC in the first month after birth; 11% of samples tested positive for salivary IgA to TSST-1 and 5% for salivary IgA to SEC. By the age of two months these proportions had increased to 36% and 33% respectively. More infants who used a dummy tested positive for salivary IgA to TSST-1 compared to infants who did not use a dummy. Levels of IgA to TSST-1 and SEC detected in the breast-milk samples varied greatly among mothers. There was a trend for infants receiving breast milk with low levels of antibody to TSST-1 or SEC to have higher levels of salivary antibody to the toxins. In conclusion, passive immunity to toxins implicated in SIDS cases varies greatly among infants. Infants are able to mount an active mucosal immune response to TSST-1 and SEC in the first month of life.  相似文献   

4.
Objective: To investigate the effect of breastfeeding in healthy boys and girls on their trajectories of percent body fat (%BF) and BMI standard deviation scores (BMI–SDS) throughout childhood. Methods and Procedures: Analyses of the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study included data from 219 male and 215 female term participants, born between 1984 and 1999, with repeated anthropometric measurements between 0.5 and 7 years and prospective data on duration of breastfeeding. Results: Among boys with an overweight mother (OW‐M), analyses adjusted for potential confounders revealed that not or shortly breastfed (≤17 weeks) boys did not experience the age‐dependent decrease in %BF seen in all children with normal weight mothers (NW‐Ms). In contrast, boys fully breastfed for >17 weeks were protected against the adverse effect of maternal overweight (effect of long breastfeeding vs. no/short breastfeeding among boys with OW‐Ms: 0.46%/year; s.e. 0.18; P = 0.01). There was also a suggestion of an interaction between maternal overweight and breastfeeding for the BMI–SDS trajectory (0.08 SDS/year; s.e. 0.04; P = 0.07). Among boys with NW‐Ms mothers and the corresponding subgroups of girls, breastfeeding had little effect on the development of %BF or BMI–SDS throughout childhood. Discussion: Our study suggests that breastfeeding could offset a potential programming effect for childhood adiposity among boys with OW‐Ms, to whom advice to breast‐feed should thus be specifically targeted.  相似文献   

5.
Early growth is of interest because it is susceptible to maternal effects and linked to fitness components for a range of species. Here we present anthropometric measurements on 23 infant olive baboons born into a captive colony in order to describe growth over the first 2 years of life, to explore maternal influences on growth, and to assess the impact of growth profiles on maternal reproduction. Six main findings emerged: 1) Infant growth rates in our colony were higher than those reported for wild populations but comparable to those observed for food-enhanced animals. 2) The ratio of infant mass to maternal mass was positively associated with reproductive parameters, such as duration of post-partum amenorrhea and interbirth interval. 3) Mothers resumed cycling and reconceived when their infants attained a relatively consistent threshold mass. 4) Infant mass-for-age was associated with maternal rank and, independently, with maternal mass such that females of high dominance rank and heavy females had relatively large infants at their resumption of cycling. 5) Low-ranking and lighter females had longer investment periods but smaller infants. They continued investment in infant through prolonged lactation until their infants reached a mass similar to that of infants of high-ranking/heavy mothers, suggesting that the lengthening of investment is essentially compensatory for slow early growth. 6) There was no relationship between infant growth and maternal activity budgets. Maternal physical and social factors, not energetics, contributed to differences among infants in growth trajectories, and infant growth temporally influenced successive reproductive events.  相似文献   

6.
Objective: We analyzed trends in height and BMI and their interaction in 6‐year‐old Chilean children over the last 15 years. Research Methods and Procedures: We calculated height for age z‐score (HAZ), BMI z‐score, prevalence of obesity, underweight, and stunting from cross‐sectional national school‐based annual population surveys in 1987, 1990, 1993, 1996, 2000, and 2002. Using mixed model analysis, we determined the risk of obesity according to height over time as odds ratios (ORs) and 95% confidence interval and the potential influence of height and year of study on BMI z‐score. Results: Over the study period, height increased by 2.8 cm in boys and 2.6 cm in girls, whereas stunting declined from 5% to 2% in both. Tallness increased by ~2%, BMI z‐score increased from +0.3 to +0.65 in boys and to +0.62 in girls, and HAZ increased from ?0.47 in boys and ?0.45 in girls to 0 in 2002. Underweight declined from 4% to 3%, whereas obesity rose from 5% to ~14%. The probability of obesity among tall children was significantly greater than that for normal height children (OR, 2.3 to 3.5). The lowest obesity risk was observed between ?2 and ?1 HAZ. The OR for obesity in the stunted relative to normal height children was variable, ranging from 1.23 to 0.65, whereas it was significant and consistently positive (1.1 to 1.7) for boys and girls when it was compared with the lowest obesity risk according to height. Discussion: Tallness is significantly associated with increased obesity risk in children, while stunting is also associated, but to a lesser degree.  相似文献   

7.
This article examines the influence of nutritional status on the emergence of deciduous dentition in a cross-sectional sample of 510 rural Rajput children from the Jubbal and Kotkhai Tehsils, Shimla District, Himachal Pradesh, India. The nutritional status of each child was evaluated using Z-scores of height/supine length-for-age (HAZ), weight-for-age (WAZ), and weight-for-height (WHZ). The effects of sex and side on deciduous dental emergence were not statistically significant. Partial correlation indicates that the number of emerged teeth (T) was more strongly correlated with height than with other anthropometric variables. In most age groups, the stunted boys and girls (HAZ <-2) had fewer emerged teeth than nonstunted age peers (HAZ >-2). The mean T in underweight children was also less than that of the normal children, with a few exceptions. The stunted children have a significantly greater likelihood of delayed emergence of deciduous dentition. Measures of linear growth status are more closely related to dental development than measures of growth in mass. The findings indicate that even moderate undernutrition can delay deciduous tooth emergence.  相似文献   

8.
Objective: To examine adiponectin, an adipocyte‐secreted hormone with anti‐inflammatory and insulin‐sensitizing effects, in relation to race or gender in younger subjects. Research Methods and Procedures: The relationship of adiponectin, quantitated by radioimmunoassay, to anthropometric and metabolic factors (fasting insulin, glucose, and leptin) and reproductive hormones was examined in 46 healthy African Americans (25 girls/21 boys) and 40 whites (20 girls/20 boys) ranging in age from 12 to 21 years. Results: There was no statistical difference in BMI or in BMI percentile among the four groups. Sums of skinfolds, but not skinfold percentile, were significantly lower in boys than girls (p = 0.001 and p = 0.896, respectively), whereas there was no difference between racial groups. Leptin was significantly greater in girls (p = 0.0002). There was no difference in fasting serum glucose, insulin, or homeostasis model assessment score among any of the groups. There was a significant negative univariate relationship between serum adiponectin and both BMI and BMI percentile for the entire group (p = 0.006 and p = 0.005). In a multivariate model, BMI percentile (p = 0.005) and the interaction between race and gender (p = 0.026) were significant predictors of serum adiponectin. In this model, African‐American boys had the lowest serum adiponectin level, 37% less than white boys, who had the highest adiponectin levels. Discussion: Serum adiponectin levels are reduced in young obese subjects (African Americans and whites) and are lower in African‐American boys than white boys. A lower adiponectin level in African‐American boys may predispose this group to a greater risk of diabetes and cardiovascular disease.  相似文献   

9.
Emerging evidence suggests that fetal environmental exposures impact on future development of obesity. The objectives of this study were to assess the relationships between (i) maternal insulin sensitivity and glucose tolerance status in pregnancy and (ii) early infant weight gain and adiposity in the first year of life. In this prospective cohort study, 301 women underwent oral glucose tolerance testing for assessment of glucose tolerance status and insulin sensitivity (ISOGTT) in pregnancy. Their infants underwent anthropometric assessment at 12 months of age, including determination of weight gain in the first year of life and sum of skinfold thickness (SFT), a measure of infant adiposity. Infant weight gain and sum of SFT at 12 months did not differ according to maternal glucose tolerance status. On univariate analyses, weight gain from 0 to 12 months and sum of SFT were negatively associated with maternal ISOGTT during pregnancy. On multiple linear regression analysis, negative independent predictors of weight gain from 0 to 12 months were maternal ISOGTT during pregnancy (t = ?2.73; P = 0.007), infant female gender (t = ?3.16; P = 0.002), and parental education (t = ?1.98; P = 0.05), whereas white ethnicity was a positive independent predictor (t = 2.68; P = 0.008). Maternal ISOGTT (t = ?2.7; P = 0.008) and parental education (t = ?2.58; P = 0.01) were independent negative predictors of sum of SFT at 12 months. Independent of maternal glucose tolerance status, maternal insulin resistance during pregnancy is associated with increased infant weight gain and adiposity over the first year of life. Further longitudinal study to evaluate obesity in this group of children will increase our understanding of the contribution of the intrauterine environment to their long‐term health.  相似文献   

10.

Objectives

Previous research has established population variation in anti‐inflammatory immunological biomarkers in human milk. This immunity is potentially ecology‐dependent and may alter the life history trade‐off between growth and maintenance in infants. The current study has two aims: (1) to assess the ecological differences in milk immunity in two populations, one from the urban U.S. and one from rural Kenya; and (2) to test the hypothesis that milk immunity can affect infant growth indicators.

Materials and Methods

Kenyan Ariaal (n = 233) and U.S. (n = 75) breastfeeding mother‐infant pairs participated in a cross‐sectional study at two separate field sites. Laboratory analysis was performed on milk for the anti‐inflammatory biomarkers TGF‐β2, sTNF‐αRI, sTNF‐αRII, and IL‐1ra using ELISA. Multiple imputation was used to extrapolate data below the limit of detection before multivariate analysis.

Results

There were significant differences between U.S. and Kenyan mothers on all four milk biomarkers, with Kenyan mothers having significantly higher sTNF‐αRI and sTNF‐αRII and lower TGF‐β2 and IL‐1ra than U.S. mothers. U.S. mothers with higher milk TGF‐β2 and IL‐1ra have infants that are significantly longer and heavier for their age, while Kenyan mothers with higher sTNF‐αRI have significantly longer and heavier infants for their age, and those with higher TGF‐β2 have marginally significantly longer infants.

Discussion

There were significant differences in ecological milk immunity between U.S. and Kenyan mothers. These differences potentially play a role in the growth of their infants. Further research in milk immunity should consider the possibility of shared maternal–infant life histories.
  相似文献   

11.
Background Causes of infant death remain unknown in significant proportions of human and non‐human primate pregnancies. Methods A closed breeding colony with high rates of infant mortality had pregnancies assessed (n = 153) by fetal measurements and maternal characteristics. Infant outcome was classified as neonatal death (stillborn or died <48 hours from birth), postnatal death (died 2–30 days) or surviving (alive after 30 days). Results Fetal size did not predict outcome. Poor maternal glycemic control and low social ranking increased odds for adverse outcome (OR = 3.72, P = 0.01 and 2.27, P = 0.04, respectively). Male sex was over‐represented in stillbirths (P = 0.04), and many were macrosomic, but size did not associate with maternal glycemic control measured as glycated hemoglobin A1c. Postnatally dead infants were smaller (P < 0.01), which associated with behavioral factors and glycemic control. Conclusions Fetal growth estimates predicted gestational age but not fetal outcome. Maternal social status and metabolic health, particularly glycemic control, increased risks of adverse pregnancy outcome.  相似文献   

12.
The paper investigates the effect of child undernutrition on the risk of mortality in Burundi. Using anthropometric data from a longitudinal survey (1998–2007) we find that undernourished children, measured by the height-for-age z-scores (HAZ) in 1998 had a higher probability to die during subsequent years. In order to address the problem of omitted variables correlated with both nutritional status and the risk of mortality, we use the length of exposure to civil war prior to 1998 as a source of exogenous variation in a child's nutritional status. Children exposed to civil war in their area of residence have worse nutritional status. The results indicate that one year of exposure translates into a 0.15 decrease in the HAZ, resulting in a 10% increase in the probability to die. For boys, we find a 0.34 decrease in HAZ per year of exposure, resulting in 25% increase in the probability to die. For girls, the results are statistically not significant at the usual thresholds. We show the robustness of our results and we derive policy conclusion for a nutrition intervention in times of conflict.  相似文献   

13.
The maternal behavior of primiparous rhesus macaques (Macaca mulatta), peer-reared since 1/2 years(s) of age as part of aHerpesvirus simiae (herpes B-virus) screening protocol, was examined and compared to a control group of conspecifics reared in their natal group. Infant survival was significantly higher in control groups as compared to the test group, a result attributed to the high incidence of infant kidnapping/abandonment in the test group. Among the test subjects, infant survival rate increased as the birth season progressed, thus it is possible that exposure to mothers/infants helped in the maternal success of those females who gave birth later in the season. Test group infants were touched by group members significantly more than the infants of control subjects, whereas these infants were groomed by their mothers and in a ventral position for a greater time relative to the infants of the test subjects. This study suggests that females, partially reared in peer groups, may be at early risk for maternal incompetence and consequent greater infant mortality, and that exposure to mother-infant dyads may augment the proficiency of maternal skills.  相似文献   

14.
Objective: Leptin, a hormone that regulates food intake and energy metabolism, is present in breast milk. The aim of this study was to determine whether milk leptin concentration is correlated with maternal circulating leptin and BMI and with body weight gain of infants. Research Methods and Procedures: A group of 28 non‐obese women (BMI between 16.3 and 27.3 kg/m2) who breast‐fed their infants for at least 6 months and their infants were studied. Venous blood and milk samples were obtained from mothers at 1, 3, 6, and 9 months of lactation, and leptin concentration was determined. Infant body weight and height were followed until 2 years of age. Results: During the whole lactation period, milk leptin concentration correlated positively with maternal plasma leptin concentration and with maternal BMI. In addition, milk leptin concentration at 1 month of lactation was negatively correlated with infant BMI at 18 and 24 months of age. A better negative correlation was also found between log milk leptin concentration at 1 and at 3 months of lactation and infant BMI from 12 to 24 months of age. Discussion: We concluded that, in a group of non‐obese mothers, infant body weight during the first 2 years may be influenced by milk leptin concentration during the first stages of lactation. Thus, moderate milk‐borne maternal leptin appears to provide moderate protection to infants from an excess of weight gain. These results seem to point out that milk leptin is an important factor that could explain, at least partially, the major risk of obesity of formula‐fed infants with respect to breast‐fed infants.  相似文献   

15.
The low activity variant of the monoamine oxidase A (MAOA) functional promoter polymorphism, MAOA‐LPR, in interaction with adverse environments (G × E) is associated with child and adult antisocial behaviour disorders. MAOA is expressed during foetal development so in utero G × E may influence early neurodevelopment. We tested the hypothesis that MAOA G × E during pregnancy predicts infant negative emotionality soon after birth. In an epidemiological longitudinal study starting in pregnancy, using a two stage stratified design, we ascertained MAOA‐LPR status (low vs. high activity variants) from the saliva of 209 infants (104 boys and 105 girls), and examined predictions to observed infant negative emotionality at 5 weeks post‐partum from life events during pregnancy. In analyses weighted to provide estimates for the general population, and including possible confounders for life events, there was an MAOA status by life events interaction (P = 0.017). There was also an interaction between MAOA status and neighbourhood deprivation (P = 0.028). Both interactions arose from a greater effect of increasing life events on negative emotionality in the MAOA‐LPR low activity, compared with MAOA‐LPR high activity infants. The study provides the first evidence of moderation by MAOA‐LPR of the effect of the social environment in pregnancy on negative emotionality in infancy, an early risk for the development of child and adult antisocial behaviour disorders .  相似文献   

16.
Blood and saliva were collected in the autumn and spring from a group of schoolchildren (39 girls, 35 boys) with a mean age of 11.4 years. Serum immunoglobulin IgG, IgA, IgM and IgE, alpha 1-antitrypsin (A 1-AT), alpha 2 macroglobulin (A 2M), transferrin (TRF), ceruloplasmin (CPL), lysozyme (LYS) and pertussis (PE) antibody levels were determined. Calcium (Ca2+) and total serum protein levels were also determined. Secretory IgA (sIgA) and secretory lysozyme (sLYS) levels were assessed in the saliva. A highly significant drop in Ca2+ levels was found in the spring in boys, while in girls there was only a greater scatter of the values. Mean IgG, IgA and IgM values fell significantly in the spring in both sexes, but IgE levels fell significantly only in boys. PE levels rose significantly in the spring in girls. Among the other proteins, all the values rose in boys, except for TRF, whose levels fell. In girls, LYS and TRF levels rose, but all the other values fell. The coefficients of correlation between Ca2+ and the tested proteins showed a significant relationship only for A 2M and PE in girls and only for the total protein level in boys; in boys, the determination coefficient for sIgA and IgM was over 10%. The results do not testify to the existence of a close relationship between blood Ca2+ levels and Ig and other blood protein levels.  相似文献   

17.
Body composition assessment during infancy is important because it is a critical period for obesity risk development, thus valid tools are needed to accurately, precisely, and quickly determine both fat and fat‐free mass. The purpose of this study was to compare body composition estimates using dual‐energy x‐ray absorptiometry (DXA) and air displacement plethysmography (ADP) at 6 months old. We assessed the agreement between whole body composition using DXA and ADP in 84 full‐term average‐for‐gestational‐age boys and girls using DXA (Lunar iDXA v11–30.062; Infant whole body analysis enCore 2007 software, GE, Fairfield, CT) and ADP (Infant Body Composition System v3.1.0, COSMED USA, Concord, CA). Although the correlations between DXA and ADP for %fat (r = 0.925), absolute fat mass (r = 0.969), and absolute fat‐free mass (r = 0.945) were all significant, body composition estimates by DXA were greater for both %fat (31.1 ± 3.6% vs. 26.7 ± 4.7%; P < 0.001) and absolute fat mass (2,284 ± 449 vs. 1,921 ± 492 g; P < 0.001), and lower for fat‐free mass (5,022 ± 532 vs. 5,188 ± 508 g; P < 0.001) vs. ADP. Inter‐method differences in %fat decreased with increasing adiposity and differences in fat‐free mass decreased with increasing infant age. Estimates of body composition determined by DXA and ADP at 6 months of age were highly correlated, but did differ significantly. Additional work is required to identify the technical basis for these rather large inter‐method differences in infant body composition.  相似文献   

18.
Background. Colonization with Helicobacter pylori generally occurs in infancy, and the microorganism is often acquired from close family members. Rate of infant colonization may be affected by maternal immune status. Methods. To investigate the potential protective effect of anti‐H. pylori immunoglobulin G (IgG) acquired via the placenta, 65 mothers and their infants were studied from the infant's birth for 1 year. Circulating IgG antibodies were measured by enzyme‐linked immunosorbent assay (ELISA) in cord blood and every 8 weeks. Immunoblotting was performed on sera from infants with significant increases in IgG levels. Rate of infant H. pylori colonization was measured by 13C urea breath tests every 4 weeks from the age of 12 weeks. Results. Maternal and infant cord blood specific IgG levels were correlated (R2 = .747, p < .001). Infant H. pylori specific IgG fell 5‐fold compared to maternal levels over the first 6 months of life, and rose subsequently in many cases, with the development of novel immunoblot patterns. There were no significant associations between the age at first positive urea breath test and maternal or infant cord specific H. pylori IgG levels. Conclusions. Transplacentally acquired specific IgG antibody does not protect infants from colonization by H. pylori.  相似文献   

19.
Harper (Parental Care in Mammals, Plenum Press, New York, 1981, p. 158) proposed that ‘there may be lower and upper limits for frequency or intensity of offspring stimulation that, on average, serve as reliable boundaries, below or above which it would be uneconomical to invest at all or at current levels.‘ This proposition was tested in captive common marmosets by comparing the responses of marmoset mothers exposed to differing number of infants. Fifteen common marmoset (Callithrix jacchus) litters (seven twin and eight triplet litters) from 11 different dams were observed for 6–12, 30‐min sessions over days 1–4 following birth. Mothers nursed smaller infants less frequently (F = 4.208, df = 1, 22; p = 0.052) regardless of litter size. The percent time mothers spent transporting (nursing and carrying) each infant was less for triplets than twins (F = 11.785, df = 1, 12; p = 0.005). Average transport bout length was significantly shorter for smaller infants (F = 7.566, df = 1, 22; p = 0.012) and was half as long for triplet infants as for twins (F = 10.733, df = 1, 7; p = 0.013). Twice as many transport bouts for triplets included maternal harassment of infants, than for twins (F = 42.742, df = 1, 24; p = 0.0001). Infant‐initiated transfers to the mother were more common for triplets than for twins (Mann–Whitney U = 79.50, p = 0.006). The overall maternal carrying score (% carry × number of infants carried) was lower for triplet litters than for twin litters (F = 15.38, df = 1, 3; p = 0.029); i.e. mothers of triplets did not, overall, invest in more carrying and nursing than did mothers of twins but instead invested less. These findings suggest that, as opposed to the strong attraction to infants that is common for many primates, the marmoset mother's tolerance for carrying infants does not increase with increasing infant stimuli present; rather, marmoset mothers will only tolerate a limited amount of time transporting and nursing infants, regardless of litter size. This limited tolerance may be due to the species’ small body size and anti‐predator strategies (e.g. concealment) that make infant care incompatible with other essential activities, such as foraging.  相似文献   

20.
Objective: To determine the ability of air displacement plethysmography (ADP) to predict visceral adipose tissue (VAT) volume in children. Research Methods and Procedures: Fifty‐five (33 boys/22 girls) white children 13 to 14 years old were studied. Anthropometric measures were collected for body mass, stature, BMI, and waist‐to‐hip ratio (WHR), and body fat percentage was estimated from triceps and subscapular skinfolds, bioelectrical impedance analysis, and ADP. VAT volume was determined using magnetic resonance imaging, using a multiple slice protocol at levels L1 to L5. Results: Boys had significantly (p ≤ 0.05) less VAT volume than girls [645.1 (360.5) cm3 vs. 1035.8 (717.3) cm3]. ADP explained the greatest proportion of the variance in VAT volume compared with the other anthropometric measures. Multiple regression analysis indicated that VAT volume was best predicted by ADP body fat percentage in boys [r2 = 0.81, SE of the estimate (SEE) = 160.1, SEE coefficient of variation = 25%] and by WHR and BMI in girls (r2 = 0.80, SEE = 337.71, SEE coefficient of variation = 33%). Discussion: Compared with the other anthropometric measures, ADP explains the greatest proportion of the variance in VAT volume in children 13 to 14 years old. For boys, ADP is the tool of choice to predict VAT volume, yet using the more simply collected measures of BMI and WHR is recommended for girls. However, large SE of the estimates remained, suggesting that if precision is needed, there is no surrogate for direct imaging of VAT.  相似文献   

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