Body Growth Pattern Research Articles

Length-Weight and Length-Length Relationships of Garra mullya (Sykes, 1839) from Ujani Wetland of Maharashtra, India

Length-weight relations give information on growth patterns and condition of fish. LWRs data is very useful for proper management and good exploitation of population of fish species. Length-weight relations are used for providing information on body growth pattern of species whether it is isometric or allometric. The present study was conducted on Garra mullya commonly called stone sucker fish for investigation of length-weight relationships (LWRs) from Ujani wetland, a dam constructed on Bhima river of Maharashtra, India. During the study period of November 2021 to October 2022, total of 202 samples were collected from local fishermen. The intercept (a value) was found to be 0.01126 and slope (b value) was 3.0499 which are in expected range of 2.5 to 3.5. The slope value was found almost equal to 3 and it indicated isometric growth of fish. Fulton’s condition factor was 1.2798 that was more than 1.0 and indicated that fishes were in good physical form in habitat.

An investigation on morphometric measurements and adaptability of Marathwadi buffaloes in the native breeding tract

The present study was carried out on 204 Marathwadi buffaloes, 154 from Livestock Farm Complex (LFC), College of Veterinary and Animal Sciences (COVAS), Udgir, Dist. Latur and50 from villages of Udgir tahsil to analyse their growth and adaptability profile. Marathwadi buffaloes were divided (age wise)into three groups (0-1 year, 1-3 year and 3 year and above).Different biometrical and physiological parameters were recorded during five consecutive years to study the growth profile and adaptability of Marathwadi buffaloes. No significant difference was observed in morphological parameters (body length, chestgirth, height at withers, body weight and body surface area)between buffaloes reared in LFC, COVAS, Udgir and under field conditions of adjoining villages in Udgir Tahsil. Body growth pattern was proportionate according to age in both the groups. However, growth parameters were comparatively lower in buffaloes under village conditions than buffaloes maintained atLFC, COVAS, Udgir. Benezra’s Coefficient of Adaptability (BCA)was used to assess the adaptability of these buffaloes and nosignificant difference was observed among the both group of buffaloes across all age groups. However, as per Iberia Heat Tolerance Coefficient (IHTC), adaptability values were nearby 100 in all groups and there was no significant difference was observed between these two groups. It is inferred that, growth pattern was proportionate with age in Marathwadi buffaloes which were reared under organised farm as compared to the animals reared under field condition

Body growth assessment in children with IgE-mediated cow's milk protein allergy fed with a new amino acid-based formula.

BackgroundAmino acid-based formula (AAF) is a relevant dietary option for non-breastfed children. The present study was designed to evaluate the body growth pattern in cow's milk protein allergy (CMPA) children treated for 6 months with a new AAF.MethodsThis was an open-label, single arm study evaluating body growth pattern in immunoglobulin E (IgE)-mediated CMPA infants receiving a new AAF for 6 months. The outcomes were anthropometry (weight, length, head circumference), adherence to the study formula and occurrence of adverse events (AEs).ResultsFifteen children [all Caucasian and born at term; 53.3% born with spontaneous delivery; 80% male; 80% with familial allergy risk; mean age (±SD) 3 ± 2.5 months at IgE-mediated CMPA diagnosis; mean age (±SD) 16.7 ± 5.9 months at enrolment, mean total serum IgE (±SD) 298.2 ± 200.4 kU/L] were included and completed the 6-month study. Data from fifteen age- and sex-matched healthy controls were also adopted as comparison. At baseline, all CMPA patients were weaned and were receiving the new AAF. All 15 patients completed the 6-month study period. For the entire CMPA pediatric patients’ cohort, from baseline to the end of the study period, the body growth pattern resulted within the normal range of World Health Organization (WHO) growth references and resulted similar to healthy controls anthropometric values. The formula was well tolerated. The adherence was optimal and no AEs related to AAF use were reported.ConclusionsThe new AAF ensured normal growth in subjects affected by IgE-mediated CMPA. This formula constitutes another suitable safe option for the management of pediatric patients affected by CMPA.

Habitat and climate shape growth patterns in a mountain ungulate.

Uptake and use of energy are of key importance for animals living in temperate environments that undergo strong seasonal changes in forage quality and quantity. In ungulates, energy intake strongly affects body mass gain, an important component of individual fitness. Energy allocation among life‐history traits can be affected by internal and external factors. Here, we investigate large‐scale variation in body growth patterns of Alpine chamois Rupicapra rupicapra rupicapra, in relation to sex, age, temperature, and habitat variations across 31 (sub)populations in the Central European Alps. Taking advantage of an exceptionally large dataset (n = 178,175) of chamois hunted over 27 consecutive years between 1993 and 2019 in mountain ranges with different proportions of forest cover, we found that (i) patterns of body mass growth differ between mountain ranges, with lower body mass but faster mass growth with increasing proportion of forest cover and that (ii) the effect of spring and summer temperatures on changes in body growth patterns are larger in mountain ranges with lower forest cover compared to mountain ranges with higher forest cover. Our results show that patterns of body mass growth within a species are more plastic than expected and depend on environmental and climatic conditions. The recent decline in body mass observed in Alpine chamois populations may have greater impacts on populations living above the treeline than in forests, which may buffer against the effects of increasing temperatures on life‐history traits.

Body growth of replacement dairy heifers from 3 distinct genetic groups from commercial Brazilian dairy herds

Few studies have been published on the body growth of replacement dairy heifers from Jersey (JER) and Holstein × Gyr (H × G) breeds, as most of them have focused on Holstein (HOL) heifers. In addition, HOL genetics vary significantly across countries. Our goal was to study the body growth curves of 3 distinct genetic groups of heifers (HOL, H × G, and JER) using data from Brazilian commercial dairy herds. Heart girth [to estimate body weight (BW)], hip height (HH), and withers height (WH) were measured. Weights (heifers and cows) and heights (only heifers) were collected from animals in several herds for each genetic group to model and describe the growth rates, mature body weight (MBW), weights, and heights for the recommended age at first breeding (RAFB) and first calving (RAFC). The RAFB values for HOL, H × G, and JER cattle were 15, 18, and 13 mo, respectively. The RAFC values for HOL, H × G, and JER cattle were 24, 27, and 22 mo, respectively. Data were obtained from 18 dairy farms located in 4 Brazilian states and analyzed using nonlinear modeling. Data were collected from 2,266 animals: 878 HOL, 610 H × G, and 778 JER cattle. We observed different body growth patterns in each genetic group. Jersey cattle matured earlier than HOL and H × G, especially for BW and HH. Mature BW of the HOL, H × G, and JER cattle was 681, 607, and 440 kg, respectively. All genetic groups reached the recommended BW at RAFB. However, the genetic groups did not reach the recommended BW at RAFC. Average daily weight gain from weaning to RAFB was 0.84, 0.53, and 0.54 kg/d for HOL, H × G, and JER cattle, respectively. Average daily gain from RAFB to RAFC was 0.53, 0.42, and 0.48 kg/d for HOL, H × G, and JER cattle, respectively. The HH at RAFB and RAFC were 130 and 139 cm for HOL, 130 and 137 cm for H × G, and 114 and 124 cm for JER. Withers height at RAFB and RAFC were 125 and 134 cm, 125 and 134 cm, and 110 and 121 cm for HOL, H × G, and JER cattle, respectively. In general, the rearing practices were adequate to reach the recommended BW at RAFB but below the recommended BW at RAFC for all genetic groups. In addition, each genetic group demonstrated different body growth patterns, especially for BW.

Estimating allometric energy allocation between somatic and gonadic growth

Abstract Quantifying growth patterns and energy allocation strategies is essential to comprehend the biological characteristics of organisms and their interactions with broader biological communities in which they reside. Mathematical models, such as mono‐ and diphasic allometric energy‐based growth models, play a pivotal role in delineating such body growth patterns. However, modelling approaches often face some major challenges that stem from both model nonlinearity and data limitation in practice. The present study investigates the nature of the challenges and develops a flexible diphasic allometric growth model. The proposed modelling framework offers an effective parameter estimation approach directly built upon statistical smoothing techniques and numerical optimisation methods. The simulation study undertaken demonstrates that the proposed approach can provide accurate parameter estimates. The illustrative example analyses the individual body and gonadic weight of subtropical cutlassfish Trichiurus japonicus from the cooler northern and warmer southern coasts of Taiwan. The results reveal the linear growth of fish in the south compared with those in the north, which distinctive growth pattern results from the lower dependency to body mass in the somatic and gonadic growth. The proposed unified modelling framework offers new advances in growth modelling to shed light upon the intraspecific life‐history strategies, quantifying growth patterns and energy allocation strategies.

Contrasting Adult Body-Size in Sister Populations of the Balearic Lizard, Podarcis lilfordi (Günther 1874) Suggests Anthropogenic Selective Pressures

Recently isolated populations offer a good biological model to infer the evolutionary forces responsible for the current divergences across populations. We coupled genetic, morphometric, ecological, and demographic analyses from three island populations of the endemic Balearic Wall Lizard, Podarcis lilfordi, (Balearic archipelago, Spain) to infer the mechanisms underlying the observed differences in body size. For each population, we described plant community structure, derived a biotic capacity index, and used individual-based data on 1369 lizards captured and released during 6 yr (2009–2015) to estimate population density and body growth patterns. We used genetic data collected on 80 individuals (∼27 for each population) to infer genetic divergences across islets and population history. Body size divergences cannot be explained by the ecological or population characteristics. Individual growth was slower in the smallest island, where lizards reached the largest average body size. In addition to having the highest density, results suggested that resource availability does not constrain asymptotic body size, but the speed at which individuals reach it does. The Approximate Bayesian Computation used to infer population history from genetic data supported the occurrence of two bottlenecks in the islet with the highest anthropogenic footprint. We emphasize the need to integrate ecological and genetic data and the importance of considering the effects of past human disturbance as an additional force in being able to model present island fauna.

Reproductive Parameters for Female Beluga Whales (<i>Delphinapterus leucas</i>) of Baffin Bay and Hudson Bay, Canada

Monitoring marine mammal populations and their habitats is crucial for assessing population status and defining realistic management and conservation goals. Environmental and anthropogenic changes in the Arctic have prompted the pursuit for improved understanding of female beluga whale (Delphinapterus leucas) spatial and temporal reproductive patterns. There are relatively few estimates for female reproductive parameters of beluga whale populations across the Arctic, and those few that are available are outdated. Here we summarize female reproductive data from samples collected through Inuit subsistence hunts of three eastern Canadian Arctic beluga populations: High Arctic/Baffin Bay (HA), Western Hudson Bay (HB), and Cumberland Sound (CS) from 1989 to 2014. We grouped the CS and HA populations into a Baffin Bay region (BB) population based on similar body growth patterns and genetic similarity. Asymptotic body length of BB beluga whales (370.9 cm) was greater than HB whales (354.4 cm) as established from Gompertz growth curves fitted for whales ranging in age from 1 – 89 y. We did not detect a significant difference in average number of pseudocervices (8.6) between regions. Differences in average age of sexual maturity (ASM) and length at sexual maturity (LSM) were identified, with evidence of BB females maturing earlier than females from HB (probability method BB = 9.9 y versus HB = 11.0 and logistic method ASM50% HB = 9.99 and BB unresolved). BB females were also longer than HB females at maturing age (logistic LSM50%: BB = 314.5 cm vs HB = 290.3). Total corpora counts were strongly correlated with age, although the number of corpora (≥ 10 mm) suggests reproductive senescence between 40 and 50 y. Improved understanding of female reproductive patterns and knowledge of changes in the spatial and temporal timing of reproductive processes are fundamental for effective conservation and sustainable management of beluga whale populations.

Evaluation of the therapeutic interventions effects on body growth pattern of infants with congenital hypothyroidism

Background: The congenital hypothyroidism (CH) is one of the most common congenital endocrine disorders as well as the most preventable mental retardation cause and body growth disorder. Several factors such as therapeutic interventions might affect the infants’ growth status. The current study was aimed to evaluate the therapeutic interventions’ effect on growth pattern of infants with congenital hypothyroidism in Yazd.
 Methods: This retrospective cohort study was performed on all neonates with CH, who were born during years 2006 and 2008. The effectiveness of therapeutic interventions indices including the age of treatment onset, the administered dosage of Levothyroxine and normalization time of T4 and TSH level on growth pattern of children with CH by measuring height, weight and head circumference during the first five years was evaluated.
 Results: The results of the current study showed a significant increase in height, weight, and head circumference in infants from early infancy to 60 months of age as well as an ascending trend of the aforementioned variables(P<0.05).
 Conclusion: The significant effect of therapeutic interventions such as the age of treatment onset less than 30 days, normalization time of TSH during 30 days after diagnosing and normalization age of T4 less than 14 days was reported on height and weight growths of patients with congenital hypothyroidism. Also, the trend of head circumference growth would be increased in patients equally.

Body growth pattern of an isolated land crab species (Johngarthia planata) (Decapoda, Gercarcinidae) from the eastern tropical Pacific: an ecological approach

This study examines the sexual differences in relative growth and morphometrical traits of the land crabJohngarthia planata(Stimpson, 1860). Individuals came from Clipperton, where an expedition was conducted in April 2015. A total of 275 individuals were captured manually, sexed and measured in seven dimensions from the carapace and chelae. Measurements were fitted to a power function to analyse the degree of allometry in growth. Results indicated that males had larger body and chelae sizes than females. For both sexes growth was negatively allometric for the carapace and positively allometric for the chelae. We hypothesize that stronger bodies in males confer advantages during intraspecific combats and their enlarged chelae are associated to their sexual behaviour. For each sex, measurements of both right and left chelae showed a homochelic condition. We suggest that these symmetrical features provide stability and balance to their body when feeding, fighting or excavating their burrows.

Evaluation of body growth in prepubertal Japanese children with obstructive sleep apnea after adenotonsillectomy over a long postoperative period

ObjectiveThe aim of this study was to identify changes in body growth patterns in prepubertal Japanese children with obstructive sleep apnea (OSA) after adenotonsillectomy (AT) over a long postoperative period. MethodsWe retrospectively analyzed the hospital records of 69 children, aged 3–10 years with OSA, who were followed-up for a median period of 38 months (range, 24–92 months) after AT. Height and weight were measured during the preoperative period and 12, and 24 months postoperatively, data were converted to standard deviation scores (SDS) using current gender- and age-specific values for the growth parameters adopted by the National growth chart of Japan. Comparisons between the pre and postoperative SDS values for height and weight were performed. The numerical data were examined statistically. ResultsThe SDS for height and weight of Japanese OSA children significantly increased 24 months post AT and continued over the entire 24-month follow-up period. Height growth acceleration after AT ended earlier in children of 6.0±1.5 years at the time of AT than in children of 4.7±1.3 years who could not catch-up. ConclusionIn prepubertal Japanese children with OSA, AT was effective for the growth of those children over a long postoperative period.

Quantification of pediatric cervical growth: anatomical changes in the sub-axial spine.

ObjectiveIn order to provide normal values of the pediatric sub-axial cervical spinal canal and vertebral body growth pattern using computed tomographic scans, a total of 318 patients less than 10 years old were included.MethodsThe growth of the vertebral body and canal space was investigated using four different age groups. The Torg ratio (TR) was calculated and all patients were classified into a low TR group and a high TR group according to a cutoff value of 1.0. To account for spinal curvature, the C3-7 angle was measured.ResultsVery little axial expansion and growth in height were observed (2.9 mm and 3.4 mm, respectively), and the spinal canal increments (1.8 mm) were much smaller than the dimensions of the vertebral body. The mean TR values were 1.03±0.14 at the C3 vertebral level, 1.02±0.13 at C4, 1.05±0.13 at C5, 1.04±0.13 at C6, and 1.02±0.12 at C7 in all patients. The mean sub-axial angle (C3-7) was 7.9±10.6° (range: -17-47°).ConclusionThe upper sub-axial spinal canal continuously increased in size compared to the lower sub-axial spine after 8 years of age. Considerable decrements in the TR was found after late childhood compared to younger ages. Generally, there were no significant differences between boys and girls in vertical length of the cervical vertebrae. However, the axial dimension of the vertebral body and the spinal canal space varied according to gender.

Relative growth, sexual maturity, and breeding season of three species of the genusPersephona(Decapoda: Brachyura: Leucosiidae): a comparative study

The relative growths ofPersephona lichtensteinii,P. mediterranea, andP. punctatawere investigated on the south-eastern Brazilian coast, focusing on differences in the growth rates between immature and mature phases, the onset of morphological sexual maturity, and the breeding seasons of these species. Crabs were collected every two months from January 1991 through to November 1992, from a shrimp fishing boat equipped with two otter-trawl nets. Significant differences in the patterns of body growth were observed between immature and mature phases of all three species. Changes in the growth rates of the chelipeds (males) and abdomen (females) observed forP. lichtensteinii,P. mediterranea, andP. punctata, seem to be related to the puberty moult for both sexes. Males ofP. mediterraneaandP. punctatareached larger mean sizes of carapace width than females, whereas no difference was recorded forP. lichtensteinii. The body size at which 50% of males attained sexual maturity was also larger inP. mediterraneaandP. punctata, and smaller inP. lichtensteinii. The absence of a pronounced sexual dimorphism and the size at the onset of sexual maturity observed only forP. lichtensteiniimight be explained by distinct reproductive strategies of males. The presence of ovigerous females during the entire sampling period suggests that all three species have a continuous reproduction pattern at the Ubatuba region. Future studies on the population structure, functional maturity, and mating system should improve the understanding of factors driving the biology and ecology of these species at a subtropical region.

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.

Variabilidad morfológica y crecimiento corporal de cuatro poblaciones de Crocodylus moreletii en cautiverio

The main goal of this study was to evaluate the effect of captivity upon morphological characteristics and body growth rates of the Morelet's crocodile (Crocodylus moreletii). The studied individuals are currently reared in the Management Unit for Wildlife Conservation (Cacahuatal), located at Veracruz, Mexico. Four populations were compared: individuals from 2 of them were born in wild conditions, whereas individuals from the other 2, were born in captivity. Morphology was similar among populations and between sexes. Body growth rates were significantly different among populations, those individuals born in natural conditions grew faster than those born in captivity. We conclude that captivity does not seem to affect the morphological expression of C. moreletii in comparison with a significant effect upon the rate of body growth. These results show that different populations of C. moreletii can exhibit differential body growth patterns depending on the conditions experienced in captivity.

Sex-specific Growth in Alpine Chamois

Studying between-sex differences in body growth has strong implications for understanding life-history tactics of animals. We used age and carcass mass data from 2,312 female and 2,622 male alpine chamois (Rupicapra rupicapra) harvested in the French Alps to model the sex-specific body growth patterns of this species. Males were heavier (asymptotic body mass: 29.6 kg) than females (22.3 kg), with an adult sexual size dimorphism of 32.4%. Sexual size dimorphism originated from both differences in body growth after 1.5 years of age and differences in length of the growth period. Females reached asymptotic body mass almost 3 years earlier (3.5 years) than males (6.2 years). We also found that females 1st reproduced before achieving asymptotic growth, at 78% of their asymptotic body mass. Between-sex differences in growth patterns in this species are most likely due to stronger selection pressure for larger size in males than in females due to intrasexual competition.

Growth, testicular development and sperm output in the dog from birth to post pubertal period.

This study was performed in Fox terrier dogs. Their mean body weight at birth is 315 g; it reaches 12 kg at 1 year of age. The body growth pattern has a sigmoid appearance with a rapid growth phase between 9 weeks and 24 weeks of age. With frequent radiographic examinations, 39 ossification centers were individualized on the long bones; they had all appeared by 25 weeks of age. The fusion of these centers is achieved between 36 and 44 weeks of age. This determination of the bone age has not proved to be a good factor to date the morphologic events of puberty. The testicular width measure is a reliable criteria which is well correlated to the other morphologic and spermatic criteria (volume of ejaculate, spermatozoa concentration). The testicular growth is rapid (width: 0,6 mm/week) between 22 and 36 weeks of age. The first spermatozoa are observed at the end of this period (32 to 34 weeks of age). During the post pubertal period, from 34 weeks to 45 weeks of age, volume of ejaculate, motility, spermatozoa concentration increase and percentage of dead spermatozoa and abnormal forms decrease.

Body growth in one montane population of Sceloporus grammicus (Sauria, Phrynosomatidae) in Central México

AbstractWe conducted an analysis of the body growth pattern of the viviparous lizard Sceloporus grammicus in one of its montane populations in Central México. We calculated 177 individual growth rates for the period comprised between June 1991 and June 1997. Von Bertalanffy growth model provided the best fit to our data in comparison with logistic models. No intersexual differences were found in the growth pattern. The constructed growth curve estimated an age at maturity of 12 and a half months for females and 14 months for males. In spite of marked seasonality in the region, growth rates were not significantly different between seasons. Our results, together with previous studies on the growth ecology of other populations of S. grammicus, suggest that in the volcanic mountains of Central México body growth, and therefore age and size at maturity, are relatively more limited during the whole year in comparison with populations inhabiting northern or lower-altitude localities.

Performance of Cotesia flavipes (Hymenoptera: Braconidae) in parasitizing Chilo partellus (Lepidoptera: Crambidae) as affected by temperature and host stage

Abstract The braconid larval parasitoid, Cotesia flavipes , is used as a biological control agent against the crambid Chilo partellus , a serious pest of cereal crops in eastern and southern Africa. We examined the survival, development parameters, and body growth patterns of the host and its parasitoid at different temperatures (22, 26, and 30 °C) using third and fourth instars of Ch. partellus . For non-parasitized hosts, larval mortality tended to be highest at lowest temperature and for parasitized at third host instars only at highest temperature. Development time of Co. flavipes immatures significantly decreased with host instar and with temperature. Sex ratio of Co. flavipes varied from male- to female-biased with increase in temperature. The increase in body weight of parasitized fourth instar Ch. partellus was higher than in non-parasitized larvae at all temperatures. Parasitism by Co. flavipes had no effect on the food uptake by Ch. partellus , but significantly less food was consumed by both parasitized and non-parasitized larvae at 26 °C. The results of this study were discussed in light of the performance of Co. flavipes under different climatic conditions.

Prenatal smoke exposure alters growth in limb proportions and head shape in the midgestation human fetus.

The objective of this study was to examine the effects of smoke exposure on the growth patterns of the head, limbs, and torso of the midgestation human fetus. Four hundred maternal/fetal pairs contributed to this analysis: 366 individuals were assessed cross-sectionally (87 smokers and 279 nonsmokers) at approximately 20 and 32 weeks, and 34 individuals were followed longitudinally at 23, 27, and 32 weeks (10 smokers, 24 nonsmokers). Ten body parameters were measured by fetal ultrasound. In both samples, controlling for day of measurement, smoke exposure was significantly associated with early growth acceleration in head and abdominal diameters at 20-27 weeks (P < 0.05). This was followed by altered head shape (a significantly smaller biparietal to occipital frontal diameter ratio at 32 weeks, P < 0.01), and a proximal/distal growth gradient as proportionately long arms (P < 0.05 at 27 and 32 weeks) and short legs were apparent by 32 weeks, with a significant reduction in the tibia/femur ratio (P = 0.04). These fetal body growth patterns, expressed in terms of size and proportionality, are consistent with the presence of chronic hypoxia associated with maternal smoking. The growth pattern differences identify that prenatal smoking is not merely an insult resulting in consistent size and growth rate reduction across developmental ages. Instead, smoke exposure alters the growth rate of individual body segments at variable developmental stages as the fetus experiences selective growth restriction and augmentation. We hypothesize that the growth patterns observed here reflect the unique pattern of fetal blood flow favoring upper body oxygen distribution and extraction, together with genetically based adaptive strategies that permit the fetus to adjust the timing and magnitude of its growth to local environmental resources. It is possible that dolichocephaly is a previously unappreciated marker of fetal hypoxia. Reduced tibial growth may be a good marker for shortfall and a useful proxy for the adequacy of circulating resources more generally.