Growth Rates of Cranes Reared in Captivity

The Auk ◽  
1986 ◽  
Vol 103 (1) ◽  
pp. 125-134 ◽  
Author(s):  
Robert E. Ricklefs ◽  
Donald F. Bruning ◽  
George W. Archibald

Abstract We measured eggs, incubation periods, growth of chicks, and masses of adults of 10 species of cranes at the Bronx Zoo and the International Crane Foundation. Growth rate constants of Gompertz equations fitted to the data varied between 0.034 and 0.057/day. These values were 50-90% of those for altricial birds of comparable adult mass, and were considerably greater than those of other precocial species, such as galliforms. Rates of growth intermediate between altricial and precocial species are consistent with the fact that crane chicks, although precocial, are brooded and fed by their parents during much of the early development period. Within species, asymptote (A) and growth-rate constant (K) of the Gompertz equations were negatively correlated, owing to their inherent relationship in the curve-fitting process. Masses of chicks during the first month after hatch were unrelated to the mass asymptote, but correlated strongly with the estimated growth-rate constant. The mass of the neonate was about 60% of the fresh mass of the egg. Egg mass was unrelated to subsequent chick mass during the first month, but correlated with the mass asymptote in two species when the relationship between A and K was accounted for statistically. Egg mass also was correlated with incubation period, fledging period, and the growthrate constant in isolated instances. Growth rate and asymptote among species were inversely related, as found among large samples of diverse bird species. The size of the egg relative to the mass of the adult was related inversely to adult mass, again consistent with patterns in other groups of birds. Fledging period was related strongly to the length of the incubation period and weakly to the asymptote to the growth curve, and it was unrelated to growth-rate constant of the Gompertz equation.

The Auk ◽  
2007 ◽  
Vol 124 (4) ◽  
pp. 1158-1167
Author(s):  
François Fournier ◽  
William H. Karasov ◽  
Kevin P. Kenow ◽  
Michael W. Meyer

AbstractWe measured the energy requirements during postnatal development of six hand-reared Common Loon (Gavia immer) chicks using continuous feeding trials and doubly labeled water. At fledging, the mean (± SE) body mass of chicks was 3,246 ± 51 g. They reached asymptotic body mass in ≈66 days and had a mean growth rate constant of 0.089 ± 0.002 day−1, which was greater than growth rate constants of other, similar-sized precocial birds. Between hatch and day 66, chicks allocated 16.5% of their metabolizable energy to new tissue, lower than the average for other bird species (20%), which might be expected considering their precocial mode of development. There was a developmental change in the assimilation efficiency of food (metabolizable energy coefficient), with a mean of 0.64 ± 0.03 in chicks aged 21 days, rising to 0.83 ± 0.07 in chicks aged 35 days.Les besoins en énergie durant la croissance chez des jeunes Gavia immer élevés en captivité


2012 ◽  
Vol 30 (5_suppl) ◽  
pp. 133-133
Author(s):  
Bamidele Adesunloye ◽  
Wilfred Donald Stein ◽  
Julia Wilkerson ◽  
Xuan Huang ◽  
Fatima H Karzai ◽  
...  

133 Background: Like ATTP [bevacizumab + thalidomide + docetaxel + prednisone], ARTP [bevacizumab + lenalidomide + docetaxel + prednisone] is active in CRPC and in both the data suggest acquired resistance does not develop, supporting a strategy that continues therapy if tolerable. Discerning amongst new therapies in CRPC would be helped by novel assessment strategies that yield answers from smaller trials and allow comparisons across trials. We have validated a novel assessment method that quantifies tumor regression (d) and growth (g) rate constants using data obtained while pts are treated in a trial. We utilized this method to evaluate a phase II trial of ARTP in CRPC contrasting this with a previous study using thalidomide instead of lenalidomide (ATTP). Methods: Using PSA values and a two-phase mathematical equation we determined d and g. A three-phase equation was used to determine resistant fractions. Results: The median log g value with ARTP (-2.84) was statistically similar (p=0.204) to that observed with ATTP (-3.16). Both therapies had similar effects on log d (ARTP=-2.18; ATTP=-2.64; p=0.404). In a subset of pts with robust data both regimen are highly effective with only 3.01% and 5.46% of tumor resistant to ATTP and ARTP, respectively. In individual pt, statistically valid g and d values could be estimated after the fourth PSA value had been obtained, long before PSA increased - providing an early indicator of treatment failure. In most pts receiving prolonged treatment – as long as 700 d – the growth rate constant did not change, despite rising PSA values, indicating acquired resistance did not develop, and that if tolerable, therapy can be continued for longer periods of time. Conclusions: The substitution of daily thalidomide with lenalidomide 14/21 days in ARTP resulted in a combination statistically as effective as ATTP. As with ATTP majority of pts experienced marked reductions in the tumor’s g, and surprisingly in most, there was no evidence of acquired resistance, g remaining unchanged over prolonged time periods. Given the tolerability of this combination, pts with marked reductions in g may benefit from prolonged ARTP therapy.


2015 ◽  
Vol 815 ◽  
pp. 129-134 ◽  
Author(s):  
Xiao Chen Xie ◽  
Xiu Chen Zhao ◽  
Ying Liu ◽  
Jing Wei Cheng ◽  
Bing Zheng ◽  
...  

The effect of Ag content on the morphology of the intermetallic compound (IMC) layer at the interface between Sn-xAg-0.7Cu (x=0.0 wt.%, 0.3 wt.%, 0.8 wt.%, 3.0 wt.%) and Cu substrate has been investigated. After reflow, the slight addition of Ag element can suppress the growth of IMC. However, as the Ag content increases, the thickness of IMC is enhanced. After aging at 150°C, the IMC growth rate constant decreases with the addition of Ag. The IMC growth rate constant of Sn-3.0Ag-0.7Cu is 0.94864×10-5μm2/s, which is the lowest among these solders. As the Ag addition is 0.8wt% and 3.0wt%, the Cu3Sn growth rate constant is 0.16641×10-5μm2/s and 0.18496×10-5μm2/s, compared to the Sn-0.7Cu solder decreased 54% and 49%, respectively. As a result, the addition of Ag element improves the anti-aging properties and suppresses the growth of Cu3Sn layer, which leads to the improvement of solder joint reliability.


2019 ◽  
Vol 15 (4) ◽  
pp. 20180837 ◽  
Author(s):  
Orvil Grunmeier ◽  
Michael D. D'Emic

Osteocytes are mature versions of osteoblasts, bone-forming cells that develop in two ways: via ‘static’ osteogenesis, differentiating and ossifying tissue in situ to form a scaffold upon which other bone can form, or ‘dynamic’ osteogenesis, migrating to infill or lay down bone around neurovasculature. A previous study regressed the volume of osteocyte lacunae derived from dynamic osteogenesis (DO) of a broad sample of extant bird species against body mass, the growth rate constant ( k ), mass-specific metabolic rate, genome size, and erythrocyte size. There were significant relationships with body mass, growth rate, metabolic rate, and genome size, with the latter being the strongest. Using the same avian histological dataset, we measured over 3800 osteocyte lacunar axes derived from static osteogenesis (SO) in order to look for differences in the strength of form–function relationships inferred for DO-derived lacunae at the cellular and tissue levels. The relationship between osteocyte lacunar volume and body mass was stronger when measuring SO lacunae, whereas relationships between osteocyte lacunar volume versus growth rate and basal metabolic rate disappeared. The relationship between osteocyte lacuna volume and genome size remained significant and moderately strong when measuring SO lacunae, whereas osteocyte lacuna volume was still unrelated to erythrocyte size. Our results indicate that growth and metabolic rate signals are contained in avian DO but not SO osteocyte lacunae, suggesting that the former should be used in estimating these parameters in extinct animals.


2016 ◽  
Vol 23 (3) ◽  
pp. 345-356 ◽  
Author(s):  
Xueyu Pang ◽  
Christian Meyer

AbstractA particle-based C3S hydration model, which mathematically connects a nucleation and growth controlled mechanism with a diffusion controlled mechanism, is developed in this study. The model is first formulated and fitted with C3S hydration in stirred dilute suspensions in Part I where interactions between different particles can be ignored, and further developed and fitted with Portland cement paste hydration in Part II to account for inter-particle interactions. Excellent agreement was observed between experimental and modeled results. Three critical rate-controlling parameters, including a parallel growth rate constant, a perpendicular growth rate constant and a diffusion constant, were identified from the proposed model. The dependencies of these parameters on particle size and initial quantity of nuclei are investigated in Part I while their dependencies on cement composition, water-cement ratio, and curing condition are studied in Part II.


1998 ◽  
Vol 39 (2) ◽  
pp. 286-291 ◽  
Author(s):  
Francis Christian ◽  
Hideaki Sohma ◽  
Toshiaki Tanaka ◽  
Hiroyuki Tanaka ◽  
Ken-ichi Ohsasa ◽  
...  

2008 ◽  
Vol 279 ◽  
pp. 117-124 ◽  
Author(s):  
G.P. Tiwari ◽  
Osamu Taguchi ◽  
Yoshiaki Iijima ◽  
G.B. Kale

High temperature beta-phase in titanium and zirconium alloy systems decomposes through an eutectoid reaction into a Ti- and Zr-rich a-solid solution and an intermetallic compound. The present paper reports the layer growth kinetics of the b-solid solution phase in elemental diffusion couples of titanium and zirconium. The growth kinetics obeys a parabolic growth law. However, the temperature dependence of the growth rate constant shows a bimodal behavior. The Arrhenius plot of the growth rate constant, which is linear at the start, becomes curved at lower temperature ranges. The deviation from the Arrhenius plot of the growth rate constant is related to the curvature in the solvus line of the b-solid solution. A theoretical model for the reaction diffusion responsible for the growth of b-solid solution is presented. The growth rate of b-phase is described by the equation 2 2 . . W k D C t b = = b D x , where k is a growth rate constant and Wb is the thickness of the b-phase formed over a period of time t, Db is the interdiffusion coefficient for the b-phase, DC is concentration range of b-phase and x is a parameter which is a function of the miscibility gaps in the phase diagram on the either side of the b-phase. The above equation provides a satisfactory description of the various aspect of the phenomenon of the growth of b-phase in Ti-and Zr-alloy systems.


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