Changes in the weight of internal organs in the fetal ontogenesis

The purpose of this work was the investigation of the development of the weight of brain, heart, lungs, liver, spleen, kidneys, adrenal glands and thymus, and the developmental relations occurring between them in human fetuses and newborns. The material covering 1908 individuals of both sexes (632 fetuses and 1276 newborns) was collected in the Department of Pathological Anatomy in Poznań. During clinical autopsies the weight of organs was determined exactly to 0.1 g and the body weight exactly to 5 g. The age of the individuals was determined on the basis of the mean conception time (14-15 day after the beginning of the last menses) and it ranged from 17 to 43 weeks of gestation. The material was divided into 7 developmental periods. The first 6 periods cover the moon months successively from the 5th to the 10th and the last period covers the three final weeks (41-43). The problems were analysed on the basis of a comprehensive statistical analysis and the obtained results of the significant statistical dependences between the organs were confronted with the biological changes of the investigated features taking place in the period of fetal ontogenesis.     

Changes in body size of newborns in Lithuania, 1974-2004

The purpose of this study was to analyse body size of Lithuanian newborns born in 1998 and 2004, and to compare results with the data from 1974. The main body size measurements - body weight, body length and body mass index (BMI) of 3281 (1705 boys and 1576 girls) live term singleton Lithuanian newborns' were analysed according to gestational age, sex and health status. The data were collected in the Clinic of Obstetrics and Gynaecology of Vilnius University (VU COG), and the comparison with the data of Lithuanian Medical Birth Register of (LMBR) was performed. No significant differences between height, weight and body mass index in 1998 and the same characteristics in 2004 were observed. Means and principal percentiles (10th, 50th, 90th) of body measurements of 37-42 weeks of gestational age newborns were obtained. The mean body length was 52.8/52.19 cm (boys/girls), body weight--3589/3454 g, BMI 12.82/12.64 correspondingly. The recent data were compared with the similar data from 1974 cohort. Statistically significant increment of body length of Lithuanian newborns was observed in all age and sex groups, whereas weight changes were less evident. The analysis of BMI demonstrated the following trend: newborns became longer, but not relatively heavier in comparison with the similar data 30 years ago. Hence, it is important to evaluate weight changes of neonate in relation with the changes in height. Further investigation of prevalence of neonatal macrosomia, possible factors of body size changes, their relationship to general health status and further health issues of the child should be explored.     

Influence of prenatal malnutrition on later body-weight gain in guinea pigs]

In prenatally underfed guinea pigs the following data were obtained: 1. On the 1st day of life the mean body weight of 18 underfed animals was significantly reduced as compared to that of 18 control animals. This difference was not compensated by postnatal feeding ad libitum but persisted up to the 36th week of life (day of sacrificing). 2. The mean food intake per day estimated over 10 days during the 5th month of life was also significantly diminished in the prenatally underfed animals. 3. A significant positive correlation was found between the body weight at birth and the adult body weight, adult body length and adult body weight/body length, when the parameters of the experimental plus control animals were evaluated together. These findings suggest that in guinea pigs, which are born in a relatively mature stage, the prenatal nutrition can influence body weight, body length and body weight/body length ratio as well as food intake in adulthood.     

Correlations of developmental end points observed after 2,4,5-trichlorophenoxyacetic acid exposure in mice.

A large-scale developmental toxicology study of 2,4,5-trichlorophenoxyacetic acid was conducted in four inbred strains and one outbred strain of mice. The most significant developmental effects observed were reduced fetal weight and increased incidences of cleft palate (malformation) and prenatal death (deaths/resorptions). The correlation coefficients among the proportion of deaths/resorptions, proportion of malformations, average fetal weights, and number of viable fetuses were investigated, with each variable measured on a per-litter basis. Generally, the correlation coefficients between average fetal weight and number of viable fetuses were negative for the control and low-dose groups in the C57BL/6, C3H/He, and BALB/c strains. Overall, the correlation coefficients between proportion of malformations and number of viable fetuses were not significant. The correlation coefficients between proportion of malformations and average fetal weight were negative for all but one case. The correlations were weak in the control and low-dose groups, in which the malformation rates were very low, and were strong in the high-dose groups. The correlation coefficients between proportion of deaths/resorptions and proportion of malformations were generally positive at the high doses; some negative correlations were observed in control and low-dose groups. The correlation coefficients between proportion of deaths/resorptions and average fetal weight were negative for the A/JAX and CD-1 strains. In summary, the strongest relationship observed was the negative correlation between fetal weight and malformation.     

Relationship between body mass, brain mass and craniometric parameters in the miniature pig Mini-Lewe

The relations between skull measurements, brain mass, and body mass were investigated in 30 female miniature pigs, being 6 month old. The relatively low correlation coefficients between the variables indicate a high variability in skull shape. We found an allometric exponent of 0.236 for the relation between brain and body mass with a coefficient of determination of 0.29. Both measurements show a highest correlation with the arcus zygomaticus width, which shows close relations with the occipital height and condylobasal length.     

Body size of newborns in relation to mother's ethnicity and education: a pilot study from Vilnius City (Lithuania), 2005-2010

The purpose of this study was to analyse body size indices of newborns in Vilnius city (Lithuania) during 2005-2010 in relation with mother's education and ethnicity, and in parallel with the changes of socio-economic situation during the recent years. The present results were based on data (N = 18,084) from the Vilnius University Clinic of Obstetrics and Gynaecology. Comparison of the present Lithuanian data with other newborn studies was made. The analysis of socio-economic and demographic indicators of Lithuania, and the comparison of Gross Domestic Product of various countries was performed. The comparison of body size of newborns' data from the different countries showed that Lithuanian newborns were among the biggest babies. Some statistically significant differences in body size of newborns from different ethnic groups were established. Body length of Lithuanian newborns (M = 52.6 cm, SD = 2.5) was higher than length of Russian, Ukrainian and Romanian newborns. Body weight of Lithuanian newborns (M = 3511 g, SD = 485) was bigger than birth weight of Russian, Polish, Ukrainian and Romanian newborns. The analysis of newborns size by mother's education showed that body weight of neonates from mothers with the university education and from each other education group was bigger in comparison with the babies from respectively lower education group. The comparison of newborns weight by mother's ethnicity in relation to education level revealed nearly no discrepancies between size of newborns from mothers with the same education level at different ethnic group. The analysis of birth parameters by year has not established a statistically significant difference between the mean values for the body weight and body length of the whole investigated contingent of the full-term, single-birth newborns from Vilnius city during the 2005-2010. However, the tendency has been revealed that newborns from mothers with lower education were the most susceptible to negative economic changes after the 2008.     

Effect of prenatal exposure to diagnostic ultrasound on the development of mice.

Pregnant Swiss albino mice were exposed to diagnostic ultrasound (3.5 MHz, approximately 65 mW) for 10 min on Day 3.5 (preimplantation period), 6.5 (early organogenesis period), or 11.5 (late organogenesis period) of gestation. Sham-exposed controls were maintained for comparison. Exposed as well as control fetuses were dissected out on the 18th day of gestation, and changes in total mortality, body weight, body length, head length, brain weight, sex ratio, and microphthalmia were recorded. Exposure on Day 3.5 of gestation resulted in a small increase in the resorption rate and a significant reduction in fetal body weight. A low fetal weight and an increase in the number of growth-retarded fetuses were produced by exposure on Day 6.5 postcoitus. A statistically nonsignificant increase in the incidence of microphthalmia was induced in fetuses exposed on Day 6.5 or Day 11.5 of gestation. These results indicate that ultrasound may have some adverse effects on the mouse embryos depending on the developmental stage at which the exposure occurred.     

The measurement of the placenta, umbilical cord and components of amniotic fluid in beagle dogs]

The body weight of newborns, the weight of placenta, the length of umbilical cord and the content of urobilinogen, gulcose, protein, pH, keton body in amniotic fluid were investigated with samples from 16 litters of beagles. The mean body weight of newborn, weight of placenta and length of umbilical cord were 258.0 +/- 44.6 g (85 samples), 48.5 +/- 8.5 g (85 samples) and 11.0 +/- 2.7 cm (52 samples), respectively without any sex difference. The significant correlation were recognized between the weight of placenta and the body weight of newborn, between the length of umbilical cord and the body weight of newborn and between the weight of placenta and the length of umbical cord (P less than 0.01).     

The influence of mother's active smoking during pregnancy on body mass index of newborns

Many investigations have noted bad influence of smoking during pregnancy. In the present article, the influence of mothers smoking during pregnancy on the body mass index (BMI), birth weight and birth length are examined. This retrospective research included 219 children: Group I: 109 children from rural area of east Slavonia (born in General Hospital-Vinkovci) and group II: 110 children from industrial area (born in Zagreb). The questioned subjects were divided into two groups depending on mothers smoking during pregnancy: newborns of mothers who didn't smoke during pregnancy (subgroup A) and newborns of mother who did smoke 10 or more cigarettes per day during pregnancy (subgroup B). Anthropometric parameters (BMI, birth length and birth weight) in newborns of non-smoking mothers were statistically higher (p < 0.05) than in newborns of smoking mothers. Moderate correlation between birth length and birth weight in newborns of non-smoking and smoking mothers from rural area and from non-smoking mothers in urban area was statistically significant, but correlation in the group in newborns of smoking mothers from Zagreb was not statistically significant. Results of this research show that smoking during pregnancy significantly influences the birth weight and birth length. Further investigation is needed, to investigate the lack of correlation between the birth length and birth weight in newborns of smoking mothers from industrial city.     

Relationship between fetal weight and malformation in developmental toxicity studies

Exposure to developmental toxicants may cause fetal malformations, increase prenatal death rates and reduce fetal weight at term. However, there has been little formal study of the relationship among these effects. Certainly, no statistical methods are currently available to jointly analyze these effects of exposure. As a preliminary step in developing such methods, simple exploratory analyses were conducted using a series of ten studies conducted for the National Toxicology Program. Because fetal weight and malformation status were both reported for all live fetuses, the data permitted an exploration of the correlation between these two outcomes. The data show a clear pattern wherein malformed fetuses tended to be lighter at term than nonmalformed fetuses. While these patterns cannot be used to draw inferences regarding the biological relationship between fetal weight and malformation, they do suggest the potential value in developing statistical models for the joint effect of exposure on fetal weight and malformations.     

Standards of morphological development in fetuses and newborns as a method of defining fetal age

Whenever the calendar age of the studied fetal material is not known we are bound to reconstruct it by replacing it with the developmental age. In this paper some common developmental standards used in the determination of fetal age are reviewed. The standards, as found in the relevant literature, are tested against a control group for their accuracy in predicting fetal age. The results indicate considerable discrepancy among the various standards. Further, the developmental ages defined by these standards often differ considerably from the known menstrual age. My own attempt to present a more reliable set of developmental standards is based on the analysis of three morphological features commonly used in biological assessment. Body weight, crown-heel length, and crown-rump length are measured in weekly termed groups representing the 20th-42nd weeks of intrauterine life. The accuracy of body weight and crown-heel length in predicting fetal age is tested both within and against a control group. Statistical analysis show no significant differences between the predicted and known fetal ages. These results indicate that body weight and crown-heel length are reliable developmental standards from which fetal age can be defined.     

Growth failure in second-trimester fetuses with trisomy 21

Growth failure in the Down syndrome is common postnatally, but is thought to be less consistent in fetuses and newborns. We describe the growth of individual organs in 53 second-trimester abortuses with trisomy 21 and compare the organ weights to organ weights from 432 spontaneously aborted, but otherwise normal control specimens. Using multiple regression analysis, we found body weight to be the most significant predictor of all organ weights in normal fetuses; therefore, this variable was used to generate the regression lines to which the organ weights of trisomic specimens were compared. All trisomic fetal organs were found to be small, with an abnormal karyotype being a significant predictor of low organ weight. However, the effect on individual organs was variable, with some organs differing only minimally from the controls. Placental weights were not affected by fetal trisomy. This study demonstrates the presence of well-established, although variably severe, growth retardation in second-trimester fetuses with Down syndrome.     

Sexual dimorphism of the weight of internal organs in fetal ontogenesis

The paper contains results of the investigation on the sexual differentiation of the weight of brain, heart, lungs, liver, spleen, kidneys, adrenal glands and thymus. The studies were carried out on a total of 632 fetuses (349 males and 283 females) and 1276 newborns (795 males and 481 females) in the age from 17 to 43 weeks of life. The study of sexual dimorphism of internal organs concludes that in the period of fetal development of man this dimorphism is weakly developed.     

Effects of AET and MEA treatment of mice on the first day of pregnancy

Porton female mice were injected intraperitoneally with 2-aminoethylisothiouronium bromide hydrobromide (AET) or cysteamine hydrochloride (MEA) in a dose of 40 mg/kg of body weight on the first day of pregnancy. On the last, nineteenth, day of gestation, taking into consideration females in whose uterus live fetuses were observed, the increase in their body weight throughout pregnancy, the number of fetuses in the uterus, the body weight of fetuses, and placental weight were found smaller in mice treated with AET or MEA, than in control ones. Among the injected compounds, AET appeared to be less toxic than MEA.     

The effects of population density on fecundity and fertility in the guppy, Poecilia reticulata (Peters)

Experiments were performed to examine the influence of population density on the fecundity and fertility in the guppy, Poecilia reticulata . The frequency of females with only ova or with different combinations of reproductive units and developmental stages in the ovary was significantly different between different densities but not between females with one and two gestations from the same population density. The ovarian width of females with one gestation from the lowest density was significantly larger than in the highest population density. Gonad length and height and ovarian volume of females with two gestation periods were larger in the lowest compared with the highest density. After one gestation, females at the lowest population level had greater ovarian length, height, gonad weight, width and volume compared with those from the higher density. Ovarian length, height and volume and gonad weight were also significantly greater among females of two gestation periods in the lowest than in the second lowest density. The average gonadosomatic ratio was highest in the lowest population density. A significant correlation was found between gonad volume and total body weight and between gonad volume and ovarian weight of females at every population level. This was also the case when ovarian weight vs. total body weight was examined in each population density. Only at the lowest population level was there a significant correlation between fecundity and total body length and between fertility and body length. A significant relationship was also found between gonad volume and total body length and between gonad weight and body length at the same population level. No significant difference of fecundity and ovum size was found between females of one and two gestation periods from the same density. Fecundity and fertility were significantly higher among females of one and two gestation periods from the lowest than from the highest density.     

Population-demographic structure of the population of Kursk region: anthropometric profile of newborn children

Based on the characteristics of body height and weight in 4905 newborns, the population-genetic structure of the rural raions (districts) of Kursk oblast (region) and in the city of Kursk was determined. An "adaptive norm area" with respect to body weight and height was distinguished for newborns in Kursk oblast. On the average, the anthropometric parameters of 20% of infants from the studied populations fell within this area. The height and growth of newborns exhibited a pronounced geographic variation and depended on the level of urbanization, as well as the sex and the health status of the newborns. In district populations, the body height and the variances of the body height and weight increased with an increase in endogamy. Therefore, the relative numbers of newborns with large values of both weight and height, as well as those with a medium body height and a small body weight, were increased. Conversely, the relative numbers of newborns with a low weight and height and with a disturbed weight-height correlation were decreased.     

多疣狭口蛙昆明种群雌雄配对行为及形态适应选择

测量和比较采自昆明东北郊的24对抱对多疣狭口蛙(Kaloulaverrucosa)标本,同时野外观察其繁殖行为。配对雌雄蛙的体长、体重和头宽3个形态特征的Pearson相关系数大于0·5;择体长和体重作回归分析,结果表明,雌雄蛙体长选择和雌雄蛙体重配对都呈良好的线性关系。雌蛙选择雄蛙体长为自身体长的(81·8±5·7)%、体重为自身体重的(53·1±10·7)%的个体为最适配偶。雌蛙选择体长较长而体重较轻的雄蛙作为配偶,这样有利于形成较好的空间(雄性胸腹部皮肤腺长度,雌雄抱对时泄殖孔位置等)配对关系。多疣狭口蛙属于雌性选择模式,即雄蛙鸣叫,雌蛙受吸引,主动接近雄蛙,如果雄蛙条件适合则形成配对。     

RELATIONS AMONGST VARIOUS LINEAR MEASUREMENTS AND WEIGHT FOR BLACK RHINOCEROSES IN KENYA

Records of black rhinoceroses obtained from different areas of Kenya suggest a very close relationship between body weight and length and chest girth. The best regressions are: log weight on log length+log girth, and weight on length x girth². The square of the correlation coefficient in both cases is more than 0.98, and the relations appear to be independent of habitat and sex. In contrast the two sexes show marked differences in the relation between front and back horn length with the males tending to grow relatively longer front horns. Attempts to predict the size of the animal and the length of its horns from the spoor were less successful.     

凡纳对虾形态性状对体重的影响效果分析

选择 6月龄凡纳对虾 176只 ,测定了体长、头胸甲长、胸宽、胸高、额剑上刺数、额剑下刺数、尾长和上市体重共 8个性状 ,采用相关分析和通径分析方法 ,剔除了与体长及头胸甲长有共线性的自变量尾长 ,计算了以形态性状为自变量对体重作依变量的相关系数、通径系数、决定系数及相关指数 ,定量地分析了形态性状对体重的影响效果。结果表明 ,凡纳对虾 5个形态性状与体重的相关系数达到极显著水平 (P<0 .0 1) ;通径分析揭示了多元分析中多个自变量与依变量的真实关系 ,体长、头胸甲长、胸宽、额剑下缘刺数目对体重的通经系数达到显著水平 ,它们是直接影响体重的重要指标 ,其中体长对体重的直接影响(0 .4 2 8* * )最大 ,是影响体重的最主要因素 ,其次为头胸甲长 (0 .2 90 * * )和胸宽 (0 .2 4 5 * * ) ,额剑下缘刺数对体重的直接影响(0 .0 70 * )较小 ;胸高与体重的相关程度很大 (0 .792 3) ,但它与额剑上缘刺数对体重的直接影响都非常小 ,主要通过其他性状间接影响活体重 ,是影响体重的次要因素 ,均被剔除 ;决定系数分析结果与通径分析结果有一致的变化趋势 ;所选形态性状与体重的复相关指数为 R2 =0 .92 13,说明影响体重的主要自变量指标已经找到 ;多元回归分析建立了体长 (X1 )、头胸甲长 (X2 )、胸宽(X3)、