Empirical Growth Curves Research Articles

Estimating Growth in Height from Limited Longitudinal Growth Data Using Full-Curves Training Dataset: A Comparison of Two Procedures of Curve Optimization-Functional Principal Component Analysis and SITAR.

A variety of models are available for the estimation of parameters of the human growth curve. Several have been widely and successfully used with longitudinal data that are reasonably complete. On the other hand, the modeling of data for a limited number of observation points is problematic and requires the interpolation of the interval between points and often an extrapolation of the growth trajectory beyond the range of empirical limits (prediction). This study tested a new approach for fitting a relatively limited number of longitudinal data using the normal variation of human empirical growth curves. First, functional principal components analysis was done for curve phase and amplitude using complete and dense data sets for a reference sample (Brno Growth Study). Subsequently, artificial curves were generated with a combination of 12 of the principal components and applied for fitting to the newly analyzed data with the Levenberg–Marquardt optimization algorithm. The approach was tested on seven 5-points/year longitudinal data samples of adolescents extracted from the reference sample. The samples differed in their distance from the mean age at peak velocity for the sample and were tested by a permutation leave-one-out approach. The results indicated the potential of this method for growth modeling as a user-friendly application for practical applications in pediatrics, auxology and youth sport.

Biomass carbon storages and carbon sequestration potentials of the Grain for Green Program-Covered Forests in China.

The Grain for Green Program (GGP) was the most all‐embracing program of ecological reconstruction implemented in China. To estimate carbon storages and carbon sequestration potentials of the GGP forests, the study presented in the paper collected data spanning from 1999 to 2010, such as tree species, tree planting area relevant to the GGP, empirical growth curves suitable for different planted tree species in China, as well as wood density (WD), biomass expansion factor (BEF), carbon fraction (CF) of different trees species, and estimated the carbon storages of the biomasses of GGP forests from 1999 to 2050. It showed that the total carbon storage of the biomass of GGP forests was 320.29 Tg upon the GGP completion in 2010; the total carbon sequestration is higher during the early GGP‐implementation stage than at the late GGP‐implementation stage, and the annual mean carbon sequestration of GGP forests was 26.69 Tg/year. The potential of GGP forests as carbon sink presented an increasing increment. In China, the potential increments of GGP forests as carbon sinks were estimated to be 397.34, 604.00, 725.53, and 808.90 Tg in 2020, 2030, 2040, and 2050, respectively, and the carbon sequestration rates were 1.72, 0.89, 0.52, and 0.36 Mg ha−1 year−1, respectively, corresponding to 2010s, 2020s, 2030s, and 2040s. Therefore, the GGP forests had bigger carbon sequestration capacities and potentials in China.

Carbon storage and carbon sequestration potential under the Grain for Green Program in Henan Province, China

As an important target province for implementation of the Grain for Green Program (GGP) in China, the carbon storage and carbon sequestration potential in living tree biomass and soil organic carbon under the GGP in Henan Province were estimated. In this study, we compiled the planted area for different tree species under the GGP in Henan Province during 200–2012 by using empirical growth curves and some parameters to estimate the carbon stock in the living tree biomass from 2000 to 2060. The empirically-based equation for the change in soil organic carbon (SOC) under China’s GGP was applied to estimate the carbon stock change in SOC for Henan Province. The total carbon storage under the Henan Province’s GGP was 51.73Tg in 2012. The total carbon storage of the later period (2007–2012) was greater than that of the earlier period (2000–2006), and the annual mean carbon sequestration was 1.63Tgyr−1 from 2000 to 2012. The carbon sequestration potential in the south zone was higher than that of other zones in Henan Province. The potential increments of carbon sink of the GGP in Henan Province are expected to reach 54.05Tg, 104.23Tg, 129.23Tg, 136.97Tg and 139.35Tg in 2020, 2030, 2040, 2050 and 2060, respectively. Therefore, Henan Province’s GGP has a large carbon sequestration function and potential.

Carbon Sequestration Potential in Stands under the Grain for Green Program in Southwest China.

The Grain for Green Program (GGP) is the largest afforestation and reforestation project in China in the early part of this century. To assess carbon sequestration in stands under the GGP in Southwest China, the carbon stocks and their annual changes in the GGP stands in the region were estimated based on the following information: (1) collected data on the annually planted area of each tree species under the GGP in Southwest China from 1999 to 2010; (2) development of empirical growth curves and corresponding carbon estimation models for each species growing in the GPP stands; and (3) parameters associated with the stands such as wood density, biomass expansion factor, carbon fraction and the change rate of soil organic carbon content. Two forest management scenarios were examined: scenario A, with no harvesting, and scenario B, with logging at the customary rotation followed by replanting. The results showed that by the years 2020, 2030, 2040, 2050 and 2060, the expected carbon storage of the GGP stands in Southwest China is 139.58 TgC, 177.50–207.55 TgC, 196.86–259.65 TgC, 240.45–290.62 TgC and 203.22–310.03 TgC (T = 1012), respectively. For the same years, the expected annual change in carbon stocks is 7.96 TgCyr−1, −7.95–5.95 TgCyr−1, −0.10–4.67 TgCyr−1, 4.31–2.24 TgCyr−1 and −0.02–1.75 TgCyr−1, respectively. This indicates that the stands significantly contribute to forest carbon sinks in this region. In 2060, the estimated carbon stocks in the seven major species of GGP stands in Southwest China are 4.16–13.01 TgC for Pinus armandii, 6.30–15.01 TgC for Pinus massoniana, 11.51–13.44 TgC for Cryptomeria fortunei, 15.94–24.13 TgC for Cunninghamia lanceolata, 28.05 TgC for Cupressus spp., 5.32–15.63 TgC for Populus deltoides and 5.87–14.09 TgC for Eucalyptus spp. The carbon stocks in these seven species account for 36.8%–41.4% of the total carbon stocks in all GGP stands over the next 50 years.

Postnatal growth and age estimation in Scotophilus kuhlii.

Adequate postnatal growth is important for young bats to develop skilled sensory and locomotor abilities, which are highly associated with their survival once independent. This study investigated the postnatal growth and development of Scotophilus kuhlii in captivity. An empirical growth curve was established, and the postnatal growth rate was quantified to derive an age-predictive equation. By further controlling the fostering conditions of twins, the differences in the development patterns between pups that received maternal care or were hand-reared were analyzed to determine whether the latter developed in the same manner as their maternally reared counterparts. Our results indicate that both forearm length and body mass increased rapidly and linearly during the first 4 weeks, after which the growth rate gradually decreased to reach a stable level. The first flight occurred at an average age of 39 days with a mean forearm length and body mass of 92.07% and 70.52% of maternal size, respectively. The developmental pattern of hand-reared pups, although similar to that of their maternally reared twin siblings, displayed a slightly faster growth rate in the 4th and 5th weeks. The heavier body mass of hand-reared pups during the pre-fledging period may cause higher wing loading, potentially influencing the flight performance and survival of the bats once independent.

西南地区退耕还林工程主要林分50年碳汇潜力

为评估西南地区退耕还林工程主要林分未来50a碳汇潜力，调查收集该地区2011年以前退耕还林工程主要造林树种及其造林面积等相关数据资料，利用国家森林资源清查资料中人工林历史数据建立生长模型，结合文献调研获得的相关林分碳计量参数，预测出本区域退耕还林工程7种主要林分碳储量和年碳储量未来变化。结果表明：西南地区退耕还林工程主要林分总碳储量在2020、2030、2040、2050和2060年分别为52.98、73.88-80.57、73.62-102.16、88.41-115.17和77.15-123.36TgC，年总碳储量则分别为3.15、-1.11-2.45、-3.92-1.95、2.08-0.96和0.25-0.73TgC，到2060年华山松、马尾松、柳杉、杉木、柏树、杨树和桉树7种林分碳汇潜力在无采伐情景下分别达到：13.01、15.01、13.44、24.13、28.05、15.63和14.09TgC，可对本地区森林碳汇功能产生明显影响。;Vegetation growth, through photosynthesis, takes up carbon dioxide from the atmosphere and converts to organic carbon into biomass thereby forms a carbon sink. Research on carbon sequestration potential of forests has become a key content to slow down global warming by forestry. To assess carbon sequestration potential in stands under the Grain for Green Program (GGP) in Southwest China, the carbon storages and their annual changes in the GGP-stands in the region were estimated based on: (1) collected data on annual planted area of each tree species under the GGP in Southwest China from 1999 to 2010; (2) empirical growth curves developed for each species of the GGP-stands using growth data about plantation from the National Forest Inventory; (3) parameters associated with stand such as wood density, biomass expansion factor, carbon fraction, the change rate in soil organic carbon content. Two scenarios for forest management option were schemed: scenario A for no harvesting and scenario B for logging at the time of maturity followed by replanting. The results showed that there are seven tree species with over 100,000 hm²of planted area in Southwest- China throughout the recent goal period of strategic planning for the GGP, and their total acreage account for 40.7% of that of all species of the GGP-stands. The expected carbon stocks in these major stands under the Grain for Green Project in Southwest China are52.98TgC, 73.88-80.57TgC, 73.63-102.16TgC, 88.41-115.17TgC and 77.15-123.36TgC(T=10¹²) by the year of 2020, 2030, 2040, 2050 and 2060, and the estimated relevant annual carbon stock changes are 3.15TgC, -1.11-2.45TgC, -3.92-1.95TgC, 2.08-0.96TgC and 0.25-0.73TgC, respectively. In 2060, the carbon stocks in forests of <em>Pinus armandii</em>, <em>Pinus massoniara</em>,<em> Cryptomeria fortunei</em>,<em> Cunninghamia laceolata</em>,<em> Cupressus </em>spp., <em>Populus deltoides</em> and <em>Eucalyptus</em> spp.under the Grain for Green Project in Southwest China will be 13.01TgC, 15.01TgC, 13.44TgC, 24.13TgC, 28.05TgC, 15.63TgC和14.09TgC, respectively, indicating a significant contribute to forest carbon sinks in this region. The <em>Cupressus </em>spp. species play a leading role in carbon sequestration potential in stands under the Grain for Green Project due to highest area proportion in Sichuan province, Chongqing municipality and even Southwest China. The <em>Cryptomeria fortune</em> and<em> Cunninghamia laceolata</em> species play a leading role in Guizhou province; the <em>Eucalyptus</em> spp. and <em>Pinus armandii</em> species in Yunnan province; the <em>Populus deltoides</em> species in Tibet autonomous region.

Empirical growth curve estimation considering multiple seasonal compensatory growths of body weights in Japanese Thoroughbred colts and fillies1

Thoroughbred horses are seasonal mating animals, and their foals are born yearly in spring seasons. In northern regions or countries, the foals generally show a typical seasonal compensatory growth pattern, where their growth rate declines in winter and increases in the next spring. In this study, a new empirical approach is proposed to adjust for this compensatory growth when growth curve equations are estimated, by using BW of Japanese Thoroughbred colts and fillies raised in Hidaka, Hokkaido. Based on the traditional Richards growth curve equation, new growth curve equations were developed and fit to the weight-age data. The foals generally experience 2 major winter seasons before their debut in horseracing. The new equations had sigmoid subfunctions that can empirically adjust the first and second year compensatory growths, combined with the Richards biological parameter responsible for the maturity of animals. The unknown parameters included in the equations were estimated by SAS NLMIXED procedure. The goodness-of-fit was examined by using several indices of goodness-of-fit (i.e., Akaike's information criterion, Bayesian information criterion, -2 log likelihood, and residual sum of squares) for the multiple applications of the subfunctions. The indices indicated the best fit of the new equations including both subfunctions for the first and second compensatory growths to the weight-age data. The shapes of the growth curves were improved during the periods of compensatory growth. The proposed method is one of the useful approaches for adjusting multiple seasonal compensatory growths in growth curve estimations of Thoroughbreds and for the management of young horses during the compensatory periods.

Empirical Percentile Growth Curves with Z-scores Considering Seasonal Compensatory Growths for Japanese Thoroughbred Horses.

Percentile growth curves are often used as a clinical indicator to evaluate variations of children’s growth status. In this study, we propose empirical percentile growth curves using Z-scores adapted for Japanese Thoroughbred horses, with considerations of the seasonal compensatory growth that is a typical characteristic of seasonal breeding animals. We previously developed new growth curve equations for Japanese Thoroughbreds adjusting for compensatory growth. Individual horses and residual effects were included as random effects in the growth curve equation model and their variance components were estimated. Based on the Z-scores of the estimated variance components, empirical percentile growth curves were constructed. A total of 5,594 and 5,680 body weight and age measurements of male and female Thoroughbreds, respectively, and 3,770 withers height and age measurements were used in the analyses. The developed empirical percentile growth curves using Z-scores are computationally feasible and useful for monitoring individual growth parameters of body weight and withers height of young Thoroughbred horses, especially during compensatory growth periods.

Empirical Growth Curve Estimation Using Sigmoid Sub-functions that Adjust Seasonal Compensatory Growth for Male Body Weight of Thoroughbred Horses.

Thoroughbred horses are seasonal mating animals, raised in northern regions or countries. Foals born yearly in spring generally show a typical seasonal compensatory growth pattern, in which their growth rate declines in the first winter and increases in the next spring. In this study, a new empirical adjustment approach is proposed to adjust for this compensatory growth when growth curve equations are estimated, by using 1,633 male body weights of Thoroughbreds as an illustrating example. Based on general Richards growth curve equation, a new growth curve equation was developed and fit to the weight-age data. The new growth curve equation had a sigmoid sub-function that can adjust the compensatory growth, combined with the Richards biological parameter responsible for the maturity of animals. The unknown parameters included in the equations were estimated by SAS NLMIXED procedure. The goodness of fit was examined by using Akaike’s Information Criterion (AIC). The AIC values decreased from 13,053 (general Richards equation) to 12,794 (the newly developed equation), indicating the better fit of the new equation to the weight-age data. The shape of the growth curve was improved during the period of compensatory growth. The proposed method is one of the useful approaches for adjusting seasonal compensatory growth in growth curve estimations for Thoroughbreds, and for their management during the compensatory period. Based on this approach, the optimal growth curve equations can be estimated also for female body weight of Thoroughbreds or other growth traits affected by seasonal compensatory growth.

Postnatal Growth and Age Estimation in the Ashy Leaf-Nosed Bat,Hipposideros cineraceus

We quantified changes in body mass, forearm length, and the total length of the epiphyseal gap of the fourth metacarpal-phalangeal joint of the ashy leaf-nosed bat (Hipposideros cineraceus) based on mark-recapture data obtained in Fangkong Cave in Hekou, Yunnan Province, China. We used these data to develop empirical growth curves, to derive growth rates, to establish age-predictive equations, and to compare growth parameters based on three nonlinear growth models. Forearm length and body mass of pups followed a linear pattern of growth until day 17, with mean growth rates of 0.81 mm/day and 0.09 g/day, respectively and thereafter their growth rates increased more slowly. The length of the epiphyseal gap initially increased linearly up to day 13 and then decreased linearly at a mean rate of 0.07 mm/day until day 37. An equation for estimating age based on forearm length was valid when this dimension was ≤ 27.6 mm, whereas the equation based on the length of the epiphyseal gap was valid for forearm lengths...

ACHANDRASURVEY OF FLUORESCENCE Fe LINES IN X-RAY BINARIES AT HIGH RESOLUTION

In this paper we present a comprehensive survey of 41 X-ray binaries (10 HMXBs and 31 LMXBs) with Chandra, with specific emphasis on the Fe K region and the narrow Fe Kalpha line, at the highest resolution possible. We find that: a) The Fe Kalpha line is always centered at 1.9387 +- 0.0016 Angstroms, compatible with Fe I up to Fe X; we detect no shifts to higher ionization states nor any difference between HMXBs and LMXBs. b) The line is very narrow, with FWHM < 5 mAngstroms, which means that the reprocessing material is not rotating at high speeds. c) Fe Kalpha fluorescence is present in all the HMXB in the survey while such emissions are very rare (~ 10% ) among LMXBs. d) The lack of Fe line emission is always accompanied by the lack of any detectable K edge. e) We obtain the empirical curve of growth of the equivalent width of the Fe Kalpha line versus the density column of the reprocessing material, i.e. EW_{Kalpha} vs N_{H}, and show that it is consistent with a reprocessing region spherically distributed around the compact object. f) We show that fluorescence in X-ray binaries follows the X-ray Baldwin effect. We interpret this finding as evidence of decreasing neutral Fe abundance with increasing X-ray illumination and use it to explain some spectral states of Cyg X-1 and as a possible cause of the lack of narrow Fe line emission in LMXBs. g) Finally, we study anomalous morphologies. We present the first evidence of a Compton shoulder in the HMXB X1908+075. Also the Fe Kalpha lines of 4U1700-37 and LMC X-4 present asymmetric wings suggesting the presence of highly structured stellar winds in these systems.

Uncertainty in detecting climate change impact on the projected yield of black spruce ( Picea mariana)

The empirical growth and yield (G&Y) curves used in most timber supply models assume that growth conditions are invariable over time, which may not be correct given the projected future climate. However, errors in G&Y models can be quite large, and we therefore wanted to know the probability of detecting climate change-induced growth anomalies as a departure from current G&Y predictions. The work was carried out in a boreal forest study area in Eastern Canada, where Picea mariana Mill. BSP (black spruce) is the dominant species. Climate change effects were incorporated into G&Y predictions as correction factors obtained from process-based simulations of growth using current or projected climate. Uncertainty in G&Y projections was quantified through the inclusion of sampling and model errors in a bootstrap re-sampling scheme that yielded a percentile distribution of possible differences between G&Y curves that included or did not include climate change effects. Results yielded an average projected increase in productivity of 29% under future climate conditions for the black spruce strata in the study area. The probability of the climate change-modified G&Y predictions being significantly different from the current G&Y projections is 75% when considering the sampling error alone, and of 67% when both the sampling and modelling errors are included. Although incomplete in terms of what sources of error have been included, this study demonstrates the type of information that can be generated on the propagation of uncertainty in G&Y projections and, ultimately, on timber supply.

Postnatal Growth and Age Estimation in Big-Footed Myotis,Myotis macrodactylus

We quantified the length of the forearm, the body mass and the length of the total gap of the fourth metacarpal-phalangeal joint of marked individuals of big-footed myotis bats (Myotis macrodactylus) from birth to flight in Dalazi Cave in Ji'an, Jilin Province, China. By using these data, we develop empirical growth curves, derive growth rates, establish age-predictive equations, and compare growth parameters based on three nonlinear growth models. Neonates of M. macrodactylus were born within a half-month period, with length of forearm averaging ca. 38.4% of the size of adult females and body mass averaging ca. 39.6% of their mother's body mass. Length of forearm increased linearly until 14 days after birth (growth rate = 1.20 mm/day), as did body mass until 11 days after birth (growth rate = 0.32 g/day). The length of the total gap of the fourth metacarpal-phalangeal joint decreased linearly from 13 days to 45 days of birth. Two most appropriate linear regression equations predicting the age of young bats were derived from forearm length ( ± SE) from 15.35 ± 0.96 mm to 33.24 ± 1.87 mm and the length of the epiphyseal gap from 13 to 45 days. These two equations make it possible to estimate the age of pups from 1 to 45 days of age in M. macrodactylus. Of the three nonlinear growth models (logistic, Gompertz, and von Bertalanffy), the logistic equation provides the best fit to the empirical curves for length of forearm and body mass.

Carbon sequestration potential of the stands under the Grain for Green Program in Yunnan Province, China

The carbon sequestration potential in living biomass and soil organic matter under the Grain for Green Program (GGP) in Yunnan Province, one of the most important target provinces of the GGP in China, was estimated in this paper using empirical curves and factors. The area of tree species planted during 2000–2007 was collected, and four scenarios for the annual area of GGP-stands to be planted during 2008–2010 and harvest options were schemed. Empirical growth curves for different tree species were developed based on data about the growth of existing plantation in Yunnan Province from National Forestry Inventory, and were used for the estimation of the carbon stocks in the tree biomass pools by incorporating with basic wood density, biomass expansion factors and carbon fraction. Empirical factors were introduced to estimate the stock change in soil organic carbon (SOC) under the GGP. The results show that the carbon stock in the GGP-stands in Yunnan Province will increase by 12.474–12.608 TgC, 33.016–35.161 TgC, 38.119–47.100 TgC, 43.057–53.626 TgC and 49.918–56.621 by the year 2010, 2020, 2030, 2040 and 2050, respectively. The annual carbon stock change in the GGP-stands will peak at 2.342–2.536 TgC per year in 2013, followed by a gradual decrease. The estimated potential carbon sequestration by GGP-stands amounts to 10.82–12.27% of the carbon stocks of forest ecosystems in Yunnan province in the 1990s.

End-weight prediction in broiler growth

1. Two different methods, categorised as input–output and single output models, were evaluated for slaughter weight prediction of broiler chickens. The input–output models included linear and non-linear recursive modelling with a time-varying model structure, whereas the output models consisted only of empirical growth equations and several growth curve fitting techniques. 2. The results suggested that a simple linear growth curve fitting method gives the greatest accuracy in a prediction horizon of 4 d or less. Error is minimised to an average of 0·14% when 4 d of past information is used to fit a line to predict the end weight one day ahead.

Formulating and parameterizing the allocation of net primary productivity for modeling overmature stands in boreal forest ecosystems

In process-based models of forest ecosystems, carbon allocation is a key process that partitions the net primary productivity (NPP) among different biomass components and thus affects forest growth patterns at different stages of the forest's growth. Common allocation models usually express the carbon allocation as linear or monotonic functions of time. These models are acceptable for a limited growth period, but inadequate for simulating long-term development of a forest. To improve the usefulness of these models and simplify the model structure, we developed an analytical solution to partition NPP that considers the effects of litterfall and growth rate. We derived NPP allocation functions based on functions for the net growth rate (dry mass) and based on empirical growth curves estimated from normal yield tables for northern Ontario, Canada. The improved allocation reflects growth restrictions that arise in overmature stands according to different site classes across landscape. The details of the derivation and parameterization are presented and discussed. We validated the new NPP allocation functions for black spruce ( Picea mariana) in the boreal forest of northern Ontario. The improved NPP allocation simulated the NPP dynamics of forest ecosystems more accurately over the course of stand development, and the results were biologically realistic.

Postnatal Growth and Age Estimation in the Mehely's Horseshoe Bat (Rhinolophus mehelyi)

Empirical growth curves were derived by measuring length of forearms, body mass and length of the total gap of the fourth metacarpal-phalangeal joint in a free ranging population of the Mehely's horseshoe bat (Rhinolophus mehelyi) in a maternity roost in western Iran. Length of forearm and body mass followed a linear pattern of growth until day 14 and subsequently decreased to reach a stable level. The length of the gap of the metacarpal-phalangeal joint showed an increase up to 10 days and decreased until it had closed at over 55 days. Initiation of flight occurred approximately four weeks after birth. During the first two weeks of postnatal growth, the body mass and the length of forearm of pups increased linearly at mean rates of 0.58 g/day and 1.55 mm/day, respectively. A method of estimation of age was derived from values of forearm length and the total gap of the four metacarpal-phalangeal joint during the preflight and post flight periods.

Lines of Circumstellar C2, CN, and CH+ in the Optical Spectra of Post-AGB Stars

Recent optical spectra of post-AGB stars show the presence of C2, CN, and CH+ originating in the circumstellar shell. We present here new, higher resolution spectra which provide constraints on the physical parameters and information on the line profiles. An empirical curve of growth for the C2 Phillips and CN Red system lines in the spectrum of HD 56126 yields b = 0.050+0.59−0.23 km s−1. CH+ (0,0) emission lines in the spectrum of the Red Rectangle have been resolved with a FWHM ≈ 8.5± 0.8 km s−1. The circumstellar CN lines of IRAS 08005-2356 are resolved into two separate components with a velocity separation of Δv = 5.7 ± 2.0 km s−1. The line profiles of CN of HD 235858 have not been resolved.

Quantitative model of the growth of floodplains by vertical accretion

A simple one-dimensional model is developed to quantitatively predict the change in elevation, over a period of decades, for vertically accreting floodplains. This unsteady model approximates the monotonic growth of a floodplain as an incremental but constant increase of net sediment deposition per flood for those floods of a partial duration series that exceed a threshold discharge corresponding to the elevation of the floodplain. Sediment deposition from each flood increases the elevation of the floodplain and consequently the magnitude of the threshold discharge resulting in a decrease in the number of floods and growth rate of the floodplain. Floodplain growth curves predicted by this model are compared to empirical growth curves based on dendrochronology and to direct field measurements at five floodplain sites. The model was used to predict the value of net sediment deposition per flood which best fits (in a least squares sense) the empirical and field measurements; these values fall within the range of independent estimates of the net sediment deposition per flood based on empirical equations. These empirical equations permit the application of the model to estimate of floodplain growth for other floodplains throughout the world which do not have detailed data of sediment deposition during individual floods. Copyright © 2000 John Wiley & Sons, Ltd.

Postnatal growth and age estimation in the Indian false vampire bat (Megaderma lyra)

AbstractThe Indian false vampire bat Megaderma lyra produces a single young under captive conditions, which is altricial at birth. Empirical growth curves were derived by measuring length of forearm, body mass and length of the total gap of the fourth metacarpal–phalangeal joint. Length of forearm and body mass followed a linear pattern of growth until day 28 and subsequently reached stability. The length of the total gap of the metacarpal–phalangeal joint initially showed a linear increase up to 4 days, followed by a linear decrease until 34 days when it closed. A quantitative method of estimation of age was derived from values of length of forearm and length of the total gap of the fourth metacarpal–phalangeal joint during the preflight (first 28 days) and postflight stages, respectively. Width of the 95% confidence level was ± 1.2 days at a mean length of forearm of 51.6 mm, and ± 0.07 days at a mean length of the total gap of the fourth metacarpal–phalangeal joint of 1.89 mm. Initiation of flight occurred 24 days after birth. At 28 days of age, young were able to forage on their own. There was no significant difference in the growth pattern of young held in captivity compared to that of young grown under natural conditions.