Inheritance of geographic variation in body size, and countergradient variation in growth rates, in the southern brown bandicoot Isoodon obesulus.

2000 ◽  
Vol 22 (1) ◽  
pp. 9 ◽  
Author(s):  
ML Hale
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Body Size ◽  
Geographic Variation ◽  
Growth Rates ◽  
Habitat Type ◽  
Adaptive Divergence ◽  
Common Environment ◽  
Countergradient Variation ◽  
Large Animals

The inheritance of geographic variation in body size in the southern brown bandicoot (Isoodon obesulus) was investigated through a common-environment crossbreeding experiment. The geographic variation in body size is related to habitat type, suggesting that it may be adaptive. Adults from two locations in Western Australia, Perth (large animals) and Albany (small animals), were collected and offspring from both hybrid and non-hybrid matings were reared under controlled conditions. All four variables examined (head length, pes length, ear length and body weight) were found to possess a large genetic component, supporting the interpretation that the geographic variation in size is adaptive. The three length variables initially showed additive genetic variation, although the variation in body weight displayed dominance. Genetically controlled differences in growth rate were also detected, with the smaller animals, found in the relatively poorer environment, possessing the faster intrinsic growth rate. Thus, not only does there appear to be adaptive divergence in initial body size, but the countergradient variation in growth rates provides additional evidence for adaptive divergence in this species.

The production characteristics of the indigenous Imroz and Kivircik sheep breeds in Turkey

2004 ◽  
Vol 34 ◽  
pp. 57-66 ◽  
Author(s):  
A. Yilmaz ◽  
M. Ozcan ◽  
B. Ekiz ◽  
A. Ceyhan ◽  
A. Altine
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Milk Production ◽  
Growth Rates ◽  
Survival Rates ◽  
Growth Characteristics ◽  
Marmara Region ◽  
Sheep Breeds ◽  
Survival And Growth ◽  
Production Characteristics

SummaryThis study was carried out to investigate the fertility, milk production and body weight of ewes and the survival and growth characteristics of lambs of the indigenous Imroz and Kivircik sheep breeds. The Imroz and Kivircik sheep breeds are included among the genetic resources in the project for the conservation of the indigenous breeds in Turkey.Conception rates for Imroz and Kivircik ewes were 57.6% and 81.7% respectively, litter sizes were 1.2 and 1.2 respectively, milk yields were 89 kg and 62 kg respectively and average live weights (2–7 years of age) were 43 kg and 55 kg, respectively. Imroz and Kivircik lambs had survival rates at weaning (90th day) of 98% and 96%, birth weights of 3.3 kg and 4.1 kg and weaning weights of 19.8 kg and 28.0 kg, respectively.The results showed that the Kivircik sheep were heavier and the lambs had a better growth rate until weaning than the Imroz breed. However, the milk production of the Imroz ewes was higher than that of Kivircik. The lambs of both breeds had a satisfactory survival and growth rates until weaning and these results might be regarded as a desired adaptation of the Imroz and Kivircik lambs to the environmental conditions of the Marmara Region.

scholarly journals Scaling of growth rate and mortality with size and its consequence on size spectra of natural microphytoplankton assemblages in the East China Sea

2013 ◽  
Vol 10 (8) ◽  
pp. 5267-5280 ◽  
Author(s):  
F. H. Chang ◽  
E. C. Marquis ◽  
C. W. Chang ◽  
G. C. Gong ◽  
C. H. Hsieh
Keyword(s):  
Growth Rate ◽  
Body Size ◽  
Growth Rates ◽  
Specific Growth ◽  
Size Structure ◽  
Scaling Exponent ◽  
The East China Sea ◽  
Size Category ◽  
Grazing Mortality ◽  
Specific Growth Rates

Abstract. Allometric scaling of body size versus growth rate and mortality has been suggested to be a universal macroecological pattern, as described by the metabolic theory of ecology (MTE). However, whether such scaling generally holds in natural assemblages remains debated. Here, we test the hypothesis that the size-specific growth rate and grazing mortality scale with the body size with an exponent of −1/4 after temperature correction, as MTE predicts. To do so, we couple a dilution experiment with the FlowCAM imaging system to obtain size-specific growth rates and grazing mortality of natural microphytoplankton assemblages in the East China Sea. This novel approach allows us to achieve highly resolved size-specific measurements that would be very difficult to obtain in traditional size-fractionated measurements using filters. Our results do not support the MTE prediction. On average, the size-specific growth rates and grazing mortality scale almost isometrically with body size (with scaling exponent ∼0.1). However, this finding contains high uncertainty, as the size-scaling exponent varies substantially among assemblages. The fact that size-scaling exponent varies among assemblages prompts us to further investigate how the variation of size-specific growth rate and grazing mortality can interact to determine the microphytoplankton size structure, described by normalized biomass size spectrum (NBSS), among assemblages. We test whether the variation of microphytoplankton NBSS slopes is determined by (1) differential grazing mortality of small versus large individuals, (2) differential growth rate of small versus large individuals, or (3) combinations of these scenarios. Our results indicate that the ratio of the grazing mortality of the large size category to that of the small size category best explains the variation of NBSS slopes across environments, suggesting that higher grazing mortality of large microphytoplankton may release the small phytoplankton from grazing, which in turn leads to a steeper NBSS slope. This study contributes to understanding the relative importance of bottom-up versus top-down control in shaping microphytoplankton size structure.

Effect of Growth Rate on Mineral Retention and Body Composition of Growing Lambs

1988 ◽  
Vol 1988 ◽  
pp. 102-102 ◽  
Author(s):  
M Wan Zahari ◽  
J K Thompson ◽  
D Scott
Keyword(s):  
Growth Rate ◽  
Body Composition ◽  
Body Weight ◽  
Calcium Carbonate ◽  
Growth Rates ◽  
Fast Rate ◽  
Basal Diet ◽  
Primary Objective ◽  
The Body ◽  
Secondary Objective

The effects of plane of nutrition on the body composition of growing sheep are very apparent when animals are compared at the same age following different nutritional histories. These differences are, however, less obvious when animals of the same breed and sex are compared at the same body weight and at present there is some conjecture whether composition is affected by growth rate. This uncertainty is not limited to fat and protein but includes the bone and ash, fraction and the ash composition.The primary objective of this trial was to study the effects of different growth rates achieved by feeding different amounts of the same concentrate diet on the composition of empty-body gain and on the retention of minerals by growing lambs. A secondary objective was to examine the effect of adding supplementary calcium carbonate to the basal diet at the fast rate of growth.

Factors influencing growth of juvenile spruce grouse

1981 ◽  
Vol 59 (9) ◽  
pp. 1790-1795 ◽  
Author(s):  
Norman W. S. Quinn ◽  
Daniel M. Keppie
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
New Brunswick ◽  
Growth Rates ◽  
Egg Laying ◽  
Maternal Influence ◽  
Juvenile Growth ◽  
Factors Influencing ◽  
Differential Timing

The influences of date of hatch, and age and prelaying body weight of brood female on the growth rate of juvenile spruce grouse (Canachites canadensis) were studied in central New Brunswick in 1977 and 1978. Because of differential timing of hatch of broods of adult and yearling females, it was not clear whether a difference in juvenile growth rates during 5–14 days of age in 1977 was related to date of hatch, age of brood female, or both. Differences in juvenile growth rates within and between years apparently were not influenced by body weight of brood females prior to egg laying. Results suggest that posthatch factors are more important in determining growth rate than a prehatch or "maternal" influence.

Incubation temperature and clutch effects on initial body sizes and growth rates in green iguana hatchlings (Iguana iguana)

2017 ◽  
Vol 67 (3-4) ◽  
pp. 239-249 ◽  
Author(s):  
Yuleimis T. Martínez-Caballero ◽  
Brian C. Bock ◽  
Isabel Pérez ◽  
Ángela M. Ortega-León ◽  
Vivian P. Páez
Keyword(s):  
Growth Rate ◽  
Body Size ◽  
Growth Rates ◽  
Egg Size ◽  
Incubation Temperature ◽  
Size Variation ◽  
Early Growth ◽  
Rate Variation ◽  
Body Sizes ◽  
Green Iguanas

Large initial body size and rapid early growth rate are important in many species, both because predation rates decline as individuals grow and because females that attain a larger adult body size are more fecund. To identify possible factors contributing to size and growth rate variation in hatchling green iguanas, we artificially incubated six clutches at three constant temperatures to test for effects of incubation temperature and/or clutch effects on initial size and growth rate. Higher incubation temperatures resulted in significantly shorter incubation periods but did not influence initial body size. There were significant differences among clutches in egg size, and also in initial hatchling body size, even after correcting for differences in egg size among clutches. A subset of hatchlings from each nest was reared in semi-natural conditions for four months, with individuals from the high incubation temperature condition exhibiting the slowest longer-term growth rates. No clutch effects were detected in the growth rate analyses. The observed variation in early growth rate of juvenile iguanas seems to be selectively important and this variation may be due in part to the conditions the eggs experience during incubation, but clutch effects in this study were limited to egg size and initial hatchling body size variation, but were not found for subsequent growth rates.

scholarly journals Breast meat quality of chickens with divergent growth rates and its relation to growth curve parameters

2017 ◽  
Vol 60 (4) ◽  
pp. 427-437 ◽  
Author(s):  
Philipp C. Muth ◽  
Anne Valle Zárate
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Meat Quality ◽  
Growth Curve ◽  
Growth Rates ◽  
Cooking Loss ◽  
Growth Potential ◽  
Breast Meat ◽  
Fast Growing ◽  
Slow Growing

Abstract. The effects of the increase of body weight of contemporary broilers during growth on functional meat quality and color characteristics of the chicken breast muscle are controversially debated. Therefore, male chickens (n = 264) of a fast-growing commercial broiler (Ross 308) and two slow-growing experimental meat-type chicken lines were compared at equal age and at similar body weight in order to investigate the effect of growth rate on selected functional breast meat traits and meat color. Additionally, the breast meat characteristics of birds with different growth profiles were compared within lines. When the body weight of commercial broilers reached about 40 to 60 % of their growth potential, they exhibited particularly high ultimate pH values compared with slow-growing lines. The ability of the meat of fast-growing broilers to retain water during cooking was impaired (5 to 16 percentage points increased cooking loss compared to slow-growing lines), which, in contrast to pH, was only marginally affected by body weight and/or age at slaughter. No unfavorable correlations of breast meat quality traits with the growth profile, represented by growth curve parameters derived from the Gompertz–Laird equation, were detected within any of the investigated chicken lines. It is noteworthy that the associations of ultimate pH and cooking loss with maximum growth speed indicate a non-linear relationship. Thus, some of the functional characteristics of breast meat of the fast-growing broiler resembled the white-striping defect described for poultry meat, but the hypothesis that selection on increased growth rates is detrimental for meat quality per se could not be confirmed. In fact, an elevated growth potential in particular, i.e., body weight at maturity, could have some beneficial effects for the water-holding capacity of breast meat, regardless of the genotypic growth rate.

scholarly journals Growth Rate and Body Size at Maturity of Florida Black Bears

2019 ◽  
Vol 10 (2) ◽  
pp. 458-467
Author(s):  
Tad M. Bartareau
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Body Size ◽  
Maximum Growth ◽  
Black Bears ◽  
Size At Maturity ◽  
Natural Diet ◽  
Human Food ◽  
Younger Age ◽  
Chest Girth

Abstract Growth rate and body size at maturity are important life-history traits of interest because they represent a potential source of fitness variance within a species and provide information for understanding the nutritional condition, fecundity, and dynamics of populations. My objective here was to examine the growth rate and body size at maturity of Florida black bears Ursus americanus floridanus using body length, chest girth, and body weight measurements fitted to the nonlinear von Bertalanffy, Gompertz, and logistic size-at-age growth functions. The von Bertalanffy model had the largest Akaike weight, indicating the best fit for all measurements of both sexes. Growth models showed that females grew more slowly, with a younger age at maximum growth, faster rate at which maturity was reached, and attained significantly smaller asymptotic body length, chest girth, and weight than males. A more conservative growth strategy by females to invest available energy resources to costs of reproduction, together with intrasexual selection among males for larger body size to enhance intimidating and fighting ability to increase reproductive and survival success, are implicated as determinants of the male-biased direction and degree of sexual size dimorphism. In both sexes, the presence of human food in the diet increased the asymptotic body weight from the estimate for bears consuming a natural diet, but differences were insignificant. Females consuming human food had a slightly younger age at maximum growth and continued growth in body weight for a somewhat longer duration than did conspecifics that consumed a natural diet. In contrast, males that consumed human food had a slightly older age at maximum growth and decreased body weight growth somewhat earlier than did conspecifics consuming a natural diet. Florida black bears exhibited a larger asymptotic body size, faster growth rate, and younger age at maximum growth and maturity when compared with conspecifics in other mainland populations. Recognition of Florida black bear growth rate and adult body size provides wildlife managers a foundation for implementing measurable criteria to assess trends in population health.

scholarly journals Modelling the growth of the brown frog (Rana dybowskii)

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4587 ◽  
Author(s):  
Qing Tong ◽  
Xiao-peng Du ◽  
Zong-fu Hu ◽  
Li-yong Cui ◽  
Hong-bin Wang
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Body Size ◽  
Management Strategies ◽  
Growth Period ◽  
The Body ◽  
Order Polynomial ◽  
Polynomial Models ◽  
Brown Frog ◽  
Rana Dybowskii

Well-controlled development leads to uniform body size and a better growth rate; therefore, the ability to determine the growth rate of frogs and their period of sexual maturity is essential for producing healthy, high-quality descendant frogs. To establish a working model that can best predict the growth performance of frogs, the present study examined the growth of one-year-old and two-year-old brown frogs (Rana dybowskii) from metamorphosis to hibernation (18 weeks) and out-hibernation to hibernation (20 weeks) under the same environmental conditions. Brown frog growth was studied and mathematically modelled using various nonlinear, linear, and polynomial functions. The model input values were statistically evaluated using parameters such as the Akaike’s information criterion. The body weight/size ratio (Kwl) and Fulton’s condition factor (K) were used to compare the weight and size of groups of frogs during the growth period. The results showed that the third- and fourth-order polynomial models provided the most consistent predictions of body weight for age 1 and age 2 brown frogs, respectively. Both the Gompertz and third-order polynomial models yielded similarly adequate results for the body size of age 1 brown frogs, while the Janoschek model produced a similarly adequate result for the body size of age 2 brown frogs. The Brody and Janoschek models yielded the highest and lowest estimates of asymptotic weight, respectively, for the body weights of all frogs. TheKwlvalue of all frogs increased from 0.40 to 3.18. TheKvalue of age 1 frogs decreased from 23.81 to 9.45 in the first four weeks. TheKvalue of age 2 frogs remained close to 10. Graphically, a sigmoidal trend was observed for body weight and body size with increasing age. The results of this study will be useful not only for amphibian research but also for frog farming management strategies and decisions.

Attained Size and Growth Rate of Female Volleyball Players between 9 and 13 Years of Age

1994 ◽  
Vol 6 (3) ◽  
pp. 257-266 ◽  
Author(s):  
Robert M. Malina
Keyword(s):  
Growth Rate ◽  
Body Size ◽  
Growth Rates ◽  
Growth Status ◽  
School Year ◽  
Body Weights ◽  
Volleyball Players ◽  
Tall Girls ◽  
Accelerated Growth ◽  
Average Body

The growth status and rate of a mixed-longitudinal sample (N = 19) of female volleyball players 9–13 years of age were compared to reference data for the general population. The athletes were measured at the beginning and end of the school year. Growth rates in stature and weight adjusted to 6-month intervals were calculated. The results indicate mean statures that are above U.S. reference medians and mean weights that are near the medians (i.e., tall girls with average body weights). Estimated half-year growth rates in stature and weight from 10.0–13.0 years closely match the respective medians of the Fels longitudinal study. The data thus suggest that the larger body size of young volleyball players is not a function of accelerated growth rate during these early adolescent ages and, thus, not due to earlier maturation; body size is likely genotypic and probably reflects selection at relatively young ages for the size demands of the sport.

scholarly journals Energy balance in rats given chronic hormone treatment

1989 ◽  
Vol 61 (3) ◽  
pp. 445-452 ◽  
Author(s):  
Christopher J. H. Woodward ◽  
Peter W. Emery
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Body Size ◽  
Energy Balance ◽  
Hormone Treatment ◽  
High Energy ◽  
Fat Free Mass ◽  
Sprague Dawley ◽  
The Difference ◽  
And Control

1. Sprague–Dawley rats were given corticosterone for 4 to 14 d either by subcutaneous injection (50 mg/kg body-weight per d) or as a higher dose in the diet (1 g/kg diet). Energy balance was calculated using the comparative carcass technique.2. Corticosterone significantly suppressed growth rate by at least 50% (P < 0·001 in all experiments). The reduction in growth was more marked in males than in females.3. Hormone treatment significantly reduced metabolizable intake (kJ/d) in males but not in females. Expressed relative to either metabolic body size (kg body-weight0·75) or fat-free mass, metabolizable intake tended to be increased in the treated groups.4. Energy expenditure, calculated as the difference between metabolizable intake and gain and expressed as kJ/d, did not differ between treated and control rats. Relative to either metabolic body size or fat-free mass, expenditure was consistently increased in treated rats. This change was statistically significant in five of the eight comparisons.5. The corticosterone-treated rat is characterized by high energy intake and expenditure relative to its body size and growth rate. Alterations in the relative sizes of different lean tissues may contribute to these changes.

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