Body Mass Increment Research Articles

Ecological and evolutionary significance of sizes of giant extinct kangaroos

A method, based on femoral circumference, allowed us to develop body mass estimates for 11 extinct Pleistocene megafaunal species of macropodids (Protemnodon anak, P. brehus, P. hopei, P. roechus, Procoptodon goliah, ‘P.’ gilli, Simosthenurus maddocki, S. occidentalis, Sthenurus andersoni, S. stirlingi and S. tindalei) and three fossil populations of the extant eastern grey kangaroo (Macropus giganteus). With the possible exception of P. goliah, the extinct taxa were browsers, among which sympatric, congeneric species sort into size classes separated by body mass increments of 20–75%. None show evidence of size variation through time, and only the smallest (‘P.’ gilli) exhibits evidence suggestive of marked sexual dimorphism. The largest surviving macropodids (five species of Macropus) are grazers which, although sympatric, do not differ greatly in body mass today, but at least one species (M. giganteus) fluctuated markedly in body size over the course of the Pleistocene. Sexual dimorphism in these species is marked, and may have varied through time. There is some mass overlap between the extinct and surviving macropodid taxa. With a mean estimated body mass of 232 kg, Procoptodon goliah was the largest hopping mammal ever to exist.

Thermal Effects on the Body mass, Transpiration rate, Feeding and Food Conversion of the Pillbug Armadillo officinalis (Isopoda, Oniscidea) Fed on the Dry Leaf of Punica Granatum

Observations were made on the body mass; transpiration rate; assimilation efficiency; gross and net production efficiencies; feeding, assimilation, conversion and metabolic rates of the pillbug Armadillo officinalis Dumeril acclimatized at 14º and 21 °C for 15 days and fed on the dry leaf of Punica granatum (Pomegranate). A brief description is given on the chemical composition of P. granatum leaf. The difference in body mass increments of A. officinalis between the acclimatized temperatures was not significant (t = 1.09; p>0.05). However, significant differences were discernible on the transpiration rate (t = 9.53; p<0.01), moisture (t = 9.01; p<0.01), assimilation efficiency (t = 5.16; p<0.01), feeding (t = 3.76; p<0.05) and conversion (t = 2.58; p<0.05) rates between the woodlice acclimatized at 14º and 21 °C. Better feeding of P. granatum leaf by these animals was observed at 21° C, but better assimilation efficiency at 14 °C. Only 3.21% assimilated food at 14° C and 6.30% at 21 °C were converted into the production of new tissues. The food consumption of A. officinalis at 14º and 21° C was 2.05% and 3.79% body mass/day respectively. The effect of temperature on the activity of A. officinalis in the field is discussed.

Growth Pattern of Stream-Dwelling Brown Trout under Contrasting Thermal Conditions

Abstract Growth of brown trout Salmo trutta was analyzed based on 3 years of simultaneous temperature and growth data from seven streams of contrasting chemical and biological character. A laboratory-based growth model was employed to examine geographical variation in growth performance among wild populations. A sensitivity analysis of model predictions was also performed based on simulated optimum temperatures for growth within the range of observed temperatures and on the optimum temperature used in the model. In spite of the diverse environmental conditions, the annual increment in body mass was not significantly different among most populations. However, the ratio of the actual growth rate to the maximum growth rate predicted by the model differed among rivers. A significant negative correlation was found between this ratio and mean annual water temperature. The growth model thus underestimated growth in the coldest rivers, suggesting that adaptations to local thermal conditions can occur at a small g...

Size and age of maturity of Atlantic salmon correlate with the North Atlantic Oscillation Index (NAOI)

Sea‐age at maturity of Atlantic salmon Salmo salar decreased with increasing values of the seasonal NAOI from February to April. Body mass increment from smolts to adults of one‐sea‐winter Atlantic salmon increased with increasing NAOI in May at the time when the juveniles moved to sea.

Long lasting cadmium intake is associated with reduction of insulin receptors in rat adipocytes.

The effects of chronic cadmium exposure on adipose tissue have not been extensively reported. In adult Wistar male rats we investigated in vivo effect of 6 weeks lasting cadmium intake in drinking tap water (CdCl2 9,7 mg/l). Insulin receptors in isolated adipocytes from epididymal fat and glucose transporter protein GLUT4 content in fat tissue plasma membranes were determined. Control and Cd treated rats had similar water intake with subsequent heavy augmentation of Cd content in liver of experimental animals. In comparison with controls, Cd intake did not influence body mass increment and fat cell size, but significantly increased serum glycemia and moderately elevated insulinemia. Cadmium intake significantly reduced (approximately 50%) both, total insulin receptors number and density of the receptors in fat cells. No differences in the content of GLUT4 in crude plasma membranes of adipose tissue were observed. Diminished insulin receptors in adipocytes could account for diabetogenic effect of long lasting cadmium intake.

Variation in growth in Sandwich Tern chicksSterna sandvicensisand the consequences for pre‐ and post‐fledging mortality

Fitness consequences of variation in body mass growth and body condition were studied in a Sandwich TernSterna sandvicensiscolony on Griend, Dutch Wadden Sea, during 1990–2000. Body mass increment during the linear growth phase predicted nestling survival probabilities accurately. Chicks growing less than 8 g per day had low survival probabilities until fledging, but within a range of 8–11 g per day growth only small effects on chick survival were observed. Effects of slow growth on survival became obvious after about 10 days after hatching. Slow growing chicks reached a much lower fledging mass, whereas slow growth had only small effects on structural size at fledging. Body condition of the chicks was highly variable and had strong effects on survival until fledging. However, body condition during the nestling stage did not influence post‐fledging survival. Body condition at fledging had no effects on post‐fledging survival and did not affect final mass or body size. It is argued that low fledging mass can be overcome soon after fledging, as parents take their fledglings closer to the foraging areas, thereby avoiding high rates of kleptoparasitism by Black‐headed GullsLarus ridibundus.

Influence of Illumination Oscillations on Growth and Energetics of the Goldfish Carassius auratus

Periodic oscillations of illumination exert a positive, rather than negative, effect on goldfish growth and energetics. In a variable light regime, the fishes grow at a higher rate, have decreased oxygen and food requirements, improve the utilization of consumed food for growth, and decrease the oxygen expenditure per increment of unit body mass. The goldfish reactions to the frequency of illumination oscillation and the succession of the stationary light regime by the oscillatory regime were described.

Effects of food shortage and oversupply on energy utilization, histology, and function of the gut in nestling song thrushes (Turdus philomelos).

We measured food intake, digestive efficiency, body mass increments, resting metabolic rate (RMR), carcass fat content, size and histological structure of the gut, and the rate of intestinal brush border uptake of l-proline in song thrush (Turdus philomelos) nestlings subjected to food shortage or food surplus under laboratory conditions. We assigned nestlings between 3 and 7 d of age to one of the following treatments: (1) food restriction, which resulted in a slowed growth at the rate found in undernourished, wild nestlings; (2) overfeeding, which totally suppressed begging; and (3) intermediate feeding. Threefold differences in energy consumption caused fivefold differences in body mass increments of the nestlings. Despite this, body mass-corrected RMR and intestinal mass were not affected by the feeding regime. The energy content of fecal output was highest in food-restricted birds, while their carcass fat content was lowest among treatment groups. Intestinal uptake rates of l-proline were low in the overfed and intermediate-fed young but significantly increased in the food-restricted birds, who attempted to maximize their rates of growth and development within the restrictive limits set by feeding regime. We noted a marked decrease of intestinal villi height in overfed birds as compared to intermediate-fed and food-restricted nestlings. We conclude that song thrush nestlings are characterized by a limited plasticity of their developmental program, which prohibits overfed nestlings from significantly up-regulating their gut function to accommodate increased food intake. This suggests that they already grew at a rate close to their physiological maximum. We suggest two interpretations: (1) under natural conditions, song thrush nestlings do not face frequent, unpredictable fluctuations in food abundance that could select for developmental plasticity, or (2) strong selection for uniform adult phenotypes prevents flexible developmental trajectories, which would result in a diversity of adult phenotypes.

Large-scale Shoreline Configuration Influences Phytoplankton Concentration and Mussel Growth

This study examines the relationship between large-scale shoreline configuration (≥100m), phytoplankton concentration and mussel growth in the St Lawrence Estuary, Canada. Cages containing mussels were moored in zones inside and external to embayments of different sizes (0·15, 1·5, 4 and 7km apertures) and along a straight coastline to evaluate mussel growth. Water samples were collected to determine phytoplankton (chlorophyll a) concentrations in the same zones. In 1993, only the 7-km embayment was studied, but all sites were studied in 1994. In 1995, nine further embayments (3×100, 3×250 and 3×400m apertures) and three sections of straight coastline were studied to examine more precisely the relationship between chla concentration and zones for small embayments. In 1993, mussel growth (shell length and body mass increments) was significantly greater inside the embayment than in zones external to it. Although growth rates for shell length and body mass were similar for 1993 and 1994 for the largest embayment, body mass increments within embayments in 1994 were greater than those observed outside of them only for the 1·5 and 4km embayments. Chlorophyll a concentration inside of small embayments (≤400m) was lower or equal to that outside of them in both 1994 and 1995 and no trends with respect to aperture size were observed. Nevertheless, 44% of the variation in the ratio of chla between zones inside and outside embayments was explained by the size of embayments (100m to 7km opening and the straight coast). Current velocity, water temperature and the flux of chla explained a high proportion of the variation in mussel growth in 1993. Further, the general patterns observed in the ratios between mussel growth within and outside of the differently sized embayments agree rather well with those of chla concentrations. Lower chla concentrations inside small embayments may be due to grazing pressure by zooplankton and bivalves.

One-year increment of fat mass and lean body mass of Japanese school children using bioelectrical impedance

Bioelectrical impedance analysis (BIA) and skinfold thickness (SF) (triceps and subscapular) methods were applied to 436 Japanese school children (228 boys and 208 girls) aged from 9 to 11 years with a one-year follow-up to determine changes in body composition. By BIA oneyear increment (Δ) of lean body mass (LBM) for boys increased significantly (p<0.01) and Δ LBM was almost equivalent to that for Δ weight (Wt). Δ Wt and Δ fat mass (FM) between the age 10 (from ages 10 to 11) and age 11 (from ages 11 to 12) groups in girls achieved statistical significance (p<0.01 and p<0.001, respectively) and Δ Wt was almost completely comprised of the Δ FM in these age groups. Δ FM in die age 11 group for girls was statistically higher than that in the age 10 group, and this obvious increase of FM in the age 11 group was presumed to be die effect of menses in consideration of die maximum oneyear increment of Ht (Δ Ht) in die age 10 group.These results of the assessment of body composition by BIA supported those of previous reports, and therefore BIA can be considered as a useful mediod to estimate changes in body composition of school children because it is simple and non-invasive and can be performed rapidly.

Competitive interactions for foraging microhabitats in a size-structured interspecific dominance hierarchy of two sympatric stream salmonids in a natural habitat

Aggressive interactions, foraging behaviour, microhabitats, and growth of individuals of two sympatric stream-dwelling salmonids, white-spotted charr (Salvelinus leucomaenis) and masu salmon (Oncorhynchus masou masou), were studied in a mountain stream in central Japan. The fishes within a single pool in the stream formed an interspecific size-structured dominance hierarchy. Dominant individuals of both species maintained foraging territories against both subordinate conspecifics and heterospecifics, whereas subordinate charr adopted nonterritorial tactics. In each species, the most dominant fish usually held the focal point nearest to the pool inlet, which ensured priority of access to drifting food, with subordinates distributed farther downstream. Foraging microhabitats differed vertically in the water column between the two species, charr utilizing a home range near the stream bed and salmon occupying the midlayer. The frequency of foraging attempts by salmon was considerably higher than that by charr. Although daily body mass increments of dominant individuals were significantly larger than those of conspecific subordinates in each species, those of some subordinate salmon exceeded those of dominant charr.

Effect of calcium, copper, and zinc levels in a rapeseed meal diet on mineral and trace element utilization in the rat.

Mineral and trace element interactions were studied in a balance trial with rats. Calcium, copper, and zinc were supplied to a rapeseed meal diet in a factorial design. Animals were fed ad libitum, and absorption, excretion, and retention of the elements were evaluated either as fractions of total intake or in relation to nitrogen retention to account for differences in food intake and lean body mass increment. The intrinsic content of minerals and trace elements was sufficient to support growth at a rate that could be expected from the rapeseed protein quality. However, when calcium was included in the diet, the intrinsic dietary level of zinc appeared to be limiting, despite the fact that the zinc level was twice the recommended level. Additional zinc supply reversed growth impairment. This calcium-zinc interaction is believed to be owing to the formation of phytate complexes. Calcium addition influenced the calcium, phosphorus, magnesium, zinc, and iron--but not the copper--balances. The addition of calcium reduced the availability of the intrinsic zinc, whereas no effect was seen in the zinc-fortified groups. The availability of intrinsic copper was in a similar way significantly impaired by addition of dietary zinc, whereas copper-supplied groups were unaffected by zinc addition. Intrinsic iron availability was also dependent upon zinc addition, although in a more ambiguous way. Thus, addition of extrinsic minerals to a diet high in phytate can result in significant impairments of growth and mineral utilization.

Fat distribution in overweight patients with Ullrich-Turner syndrome.

Overweight patients with Ullrich-Turner syndrome (UTS) and control children with similar weight/height and indices of overweight were studied to clarify the unique fat distribution in the syndrome. Triceps and ulnar skin-fold thickness (SFT) in UTS patients was significantly less than that of obese children without the syndrome. The means of SFT at the subscapular and paraumbilical regions were also less in the patients than control girls, though significance was not documented. Thus, increased body weight in UTS children seems mainly to be due to excess of adipose tissue, not in the limbs but on the trunk, and/or due to the increment of lean body mass.

The effect of anabolic steroids on lean body mass: The dose response curve

Data from human subjects given various amounts of anabolic steroids show that the resultant increment in lean body mass (LBM) has the features of a typical dose response curve. Low doses produce a very modest effect, while large doses result in a progressive augmentation of the LBM. Endogenous testosterone production during male adolescence is accompanied by a sex differential in LBM that is comparable to the LBM increment generated by exogenous steroids given to adults.

Variations in Seasonal Nutrition, Thermoregulation and Water Balance in Two New Zealand Populations of the Common Brushtail Possum, Trichosurus Vulpecula (Phalangeridae).

Two populations of common brushtail possum, at Wanganui in the North Island of New Zealand and Westland in the South Island, were compared in aspects of nutrition, thermoregulation and water balance at 2 thermal conditions in controlled-environment rooms. The thermal conditions and adaptation had no influence on nutrition and water balance but caused variation in bodyweight and in rates of food intake and water turnover, both relative to metabolic body size. Although the 2 populations differed greatly in body mass they had different rates of food intake relative to metabolic size, but similar individual rates. Rates of metabolized energy intake followed a similar pattern. Conversely, rates of water turnover relative to metabolic size were similar between populations but differed for individuals. The trend for differences between populations in indices of urine concentration were associated with different patterns of food and water intakes. These differences cannot be explained in terms of body mass increments. The physiological variation between populations was greatly influenced by differences in body size, which accord with Bergmann's rule. The larger size of the Westland animals is advantageous during abstinence from feeding during frequent foul weather, and the smaller size of the Wanganui animals confers advantages in water balance during annual periods of prolonged rainfall deficiency.

Growth and Growth Velocity of Lean Body Mass and Fat in Adolescent Boys

Beginning at age 10 years, height, weight, body density, and bone age of 40 normal boys were measured yearly over a period of 8 years. From body density, lean body mass and body content of fat were calculated. Values for all measurements are included in the Appendix and mean values, including those for lean body mass and percentage of body fat, are presented for each year in Table 1. Coefficients of correlation between measurements made during the first and eighth years of study were high for height (0.68), weight (0.50), and lean body mass (0.60), but relatively low for body fat (0.25). Correlation coefficients between the various parameters in a given year are presented in Table 2. The maximum yearly increment in height, weight, and lean body mass of individual subjects coincided in time. The respective mean values for the year of maximum growth were 9.4 cm, 8.1 kg, and 7.5 kg. Throughout the growth spurt, the contribution of fat to increase in body weight was small. It may be concluded that, next to height, the absolute amount of lean body mass demonstrates the most constant trend of development during adolescence.

Growth and Growth Velocity of Lean Body Mass and Fat in Adolescent Boys

Extract: Beginning at age 10 years, height, weight, body density, and bone age of 40 normal boys were measured yearly over a period of 8 years. From body density, lean body mass and body content of fat were calculated. Values for all measurements are included in the Appendix and mean values, including those for lean body mass and percentage of body fat, are presented for each year in Table 1. Coefficients of correlation between measurements made during the first and eighth years of study were high for height (0.68), weight (0.50), and lean body mass (0.60), but relatively low for body fat (0.25). Correlation coefficients between the various parameters in a given year are presented in Table 2. The maximum yearly increment in height, weight, and lean body mass of individual subjects coincided in time. The respective mean values for the year of maximum growth were 9.4 cm, 8.1 kg, and 7.5 kg. Throughout the growth spurt, the contribution of fat to increase in body weight was small. It may be concluded that, next to height, the absolute amount of lean body mass demonstrates the most constant trend of development during adolescence. Speculation: Lean body mass, like weight and height, follows individual patterns that are consistent throughout adolescence. The trends in height and lean body mass are more constant than trends in body weight.

Growth and metabolism in normal and thyroid-ablated infant rhesus monkeys (Macaca mulatta). IV. Radiosodium (Na24) space in normal and thyroid-ablated infant rhesus monkeys (Macaca mulatta).

THE PURPOSE of this communication is to relate Na 24 space data with previously reported growth and metabolic studies in normal and thyroid-ablated infant macaque monkeys. 1 Na 24 space was sought as a measure of one relatively constant increment of total body mass and was determined at varying intervals during growth and compared in normal and myxedematous subjects. METHODS Techniques of animal care and feeding have been reported in a previous communication. 1a Radiosodium (Na 24 ) was procured from the Oak Ridge National Laboratory, where it was prepared by neutron bombardment of sodium carbonate. The half-life of Na 24 is 14.9 hours. Samples received in this laboratory were prepared as isotonic sterile solutions and diluted with 0.85% NaCl to contain approximately 10 μc per cubic centimeter at the time of animal injection. The quantity of isotope present in samples was determined with a scintillation counter. This was composed of