Taxonomic Differences in the Mammalian Life Span-Body Weight Relationship and the Problem of Brain Weight

Gerontology ◽  
1980 ◽  
Vol 26 (2) ◽  
pp. 90-98 ◽  
Author(s):  
Angelos C. Economos
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Brain Weight ◽  
Weight Relationship

Encephalization of The Koala, Phascolarctos cinereus.

1998 ◽  
Vol 20 (3) ◽  
pp. 315
Author(s):  
C. De Miguel ◽  
M. Henneberg
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Brain Size ◽  
South Australia ◽  
Allometric Equation ◽  
Brain Weight ◽  
Phascolarctos Cinereus ◽  
Weight Relationship ◽  
Body Weights

Brain size relative to body size is considered to be an indicator of variously defined 'braininess' (=encephalization). Indices of encephalization are based on the ratio of the animal's actual brain size to its expected brain size calculated from an allometric equation derived from a brain size I body weight relationship in a series of taxa Freshly collected data on brain and body weights of 27 adult koalas (Phascolarctos cinereus) from South Australia are analysed here. Sex- averaged brain weight in this sample is 19.2 g and body weight is 8.0 kg. General equations for mammals produce encephalization values for the koala well below the mammalian average: EQ=38.9% ac- cording to Jerison's equation (1973), EQ= 49.7% applying Eisenberg's equation (1981) and EQ= 35.3% using Martin's equation (1990). When a 'basal' insectivore line is used, the koala appears to be progressive: IP =155.9% according to Stephan's equation (1972) and ICC= 131.7% using Martin's equation (1990). Use of 'basal' marsupial lines also indicates progressive encephalization of the koala: Pl=l l6.5% according to Pirlot's equation (1981}, E=108.4% following Nelson and Stephan's equation (1982) and E=107.9% using Haight and Nelson's equation (1987). These new results are clearly higher than the indices for the koala reported earlier by other authors (Nelson and Stephan 1982; Haight and Nelson 1987). It follows that choice of samples and equations influences conclusions regarding encephalization of a species.

scholarly journals Genetic Regulation of Life Span, Metabolism, and Body Weight in Pohn, a New Wild-Derived Mouse Strain

2012 ◽  
Vol 68 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Rong Yuan ◽  
Kevin Flurkey ◽  
Qingying Meng ◽  
Mike C. Astle ◽  
David E. Harrison
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Mouse Strain ◽  
Genetic Regulation

scholarly journals Lactoferrin beneficially influences the recovery of physiological and behavioral indexes in mice exposed to acute gamma-irradiation

2020 ◽  
pp. 29-33 ◽  
Author(s):  
М.Ю. Копаева ◽  
И.Б. Алчинова ◽  
М.В. Нестеренко ◽  
А.Б. Черепов ◽  
И.Ю. Зарайская ◽  
...  
Keyword(s):  
Body Weight ◽  
Survival Rate ◽  
Gamma Irradiation ◽  
Life Span ◽  
Open Field Test ◽  
Whole Body ◽  
Sublethal Dose ◽  
Male Mice ◽  
Research Activity ◽  
Compensatory Effect

Целью настоящей работы стало исследование эффектов лактоферрина (Лф) человека у мышей после острого гамма-облучения в сублетальной дозе. Методы. Исследование было проведено на 2-2,5-месячных самцах мышей линии C57Bl/6. Животные из экспериментальных групп были подвергнуты общему воздействию гамма-излучения в дозе 7,5 Гр. Сразу после облучения и повторно через 24 часа после него часть животных получила инъекцию Лф (внутрибрюшинно, 4 мг на животное). Было изучено влияние Лф на выживаемость и среднюю продолжительность жизни мышей. Для оценки общей двигательной и исследовательской активности использовали тест «Открытое поле». Результаты. Введение Лф позволило увеличить выживаемость и среднюю продолжительность жизни облученных мышей в течение эксперимента. Происходила более быстрая нормализация динамики изменения массы тела. Кроме того, Лф оказал компенсаторное действие на исследовательскую активность облученных животных. The aim of this study was to investigate effects of human lactoferrin (Lf) in mice exposed to acute gamma-irradiation at a sublethal dose. Methods. C57Вl/6 2-2.5-month-old male mice were used for the experiments. Animals from experimental groups were exposed to whole-body gamma-radiation at a dose of 7.5 Gy. Some animals received an intraperitoneal injection of Lf (4 mg per animal) immediately and then at 24 hours after the irradiation. The effect of Lf on survival rate and life span was studied. The open field test was used to assess locomotor and research activity. Results. The Lf administration increased the survival rate and life span of irradiated mice during the experiment. The dynamics of body weight normalized faster. In addition, Lf exerted a compensatory effect on the research activity of irradiated animals.

scholarly journals Length-weight relationship and condition factor of Clariid fish species in Kano Rivers, Kano State, Nigeria

2021 ◽  
Vol 44 (3) ◽  
pp. 135-139
Author(s):  
I. O. Suleiman ◽  
G.N. Akpa ◽  
P. I. Bolorunduro
Keyword(s):  
Body Weight ◽  
Condition Factor ◽  
Clarias Gariepinus ◽  
Water System ◽  
Well Being ◽  
Weight Relationship ◽  
Tropical Water ◽  
Fish Samples ◽  
Heterobranchus Longifilis ◽  
State Body

Fish found in natural tropical and sub-tropical water system experience frequent growth fluctuations. The study was conducted to determine the length-weight relationship and condition factor of Clariid species (Clarias gariepinus, Heterobranchus longifilis and Synodontis clarias) in Kano state of Nigeria. About 177 fish samples were collected from six rivers (Thomas, Ghari, Tiga, Duddurun-Gaya, Karaye and Bagwai) across the length and breadth of Kano state. Body weight (BW=248.48g), total length (TL=32.74cm) and standard length (SL=26.16cm) were determined. The length-weight relationship and condition factors were also determined. The condition factors showed varying degree of well-being of fish sampled from their habitat, and ranged from K = 0.37 to 0.89. The equation for the lengthweight relationship for the three strains is: C. gariepinus = -329.86+17.56TL, H. longifilis = -241.49+14.28TL and C. clarias = -428.51+22.72TL. Body weight and length had positive and significant relationship (r = 0.73 TL; r = 0.75 SL).

Brain Weight-Body Weight Scaling in Breeds of Dogs and Cats

1979 ◽  
Vol 16 (3) ◽  
pp. 227-236 ◽  
Author(s):  
Roderick T. Bronson
Keyword(s):  
Body Weight ◽  
Brain Weight ◽  
Weight Scaling

Breeding Biology of Brushtail Possums Trichosurus vulpecula (Marsupialia, Phalangeridae) in Captivity.

1995 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
R.T. Gemmell
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Post Partum ◽  
Young Female ◽  
Brushtail Possum ◽  
Lactation Period ◽  
In Captivity ◽  
In The Wild ◽  
The Mean ◽  
Reproductive Capability

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.

Brain-to-body ratios and time of maturation of the mouse brain

1963 ◽  
Vol 204 (2) ◽  
pp. 343-346 ◽  
Author(s):  
Tsukasa Kobayashi
Keyword(s):  
Body Weight ◽  
Short Duration ◽  
Mouse Brain ◽  
Abrupt Change ◽  
Brain Weight ◽  
Second Phase ◽  
The Third ◽  
Third Phase ◽  
The Brain

Studies on the relationships of brain weight to body weight during development were conducted in 218 mice, and revealed three distinct phases. During the first phase, the ratios are relatively constant. The second phase of short duration is characterized by abrupt reductions. In the third phase, which is the most enduring, the ratios again assume more constant values. The abrupt change in the ratios took place around 14 days of age. It is suggested that the abrupt change in the ratio is, in general, an indicator of the maturation of the brain, because there are several other parameters which approach mature levels around the 15th day. A review of the data on other species supports this suggestion.

scholarly journals Identifying Characteristics of Frailty in Female Mice Using a Phenotype Assessment Tool

2019 ◽  
Vol 75 (4) ◽  
pp. 640-646 ◽  
Author(s):  
Dongmin Kwak ◽  
Cory W Baumann ◽  
LaDora V Thompson
Keyword(s):  
Physical Activity ◽  
Body Weight ◽  
Life Span ◽  
Walking Speed ◽  
Assessment Tool ◽  
Preclinical Studies ◽  
Frailty Phenotype ◽  
Female Mice ◽  
Yield Information ◽  
Underlying Mechanisms

Abstract Preclinical studies are important in identifying the underlying mechanisms contributing to frailty. Frailty studies have mainly focused on male rodents with little directed at female rodents. Therefore, the purposes of this study were to identify the onset and prevalence of frailty across the life span in female mice, and to determine if frailty predicts mortality. Female C57BL/6 (n = 27) mice starting at 17 months of age were assessed across the life span using a frailty phenotype, which included body weight, walking speed, strength, endurance, and physical activity. The onset of frailty occurred at approximately 17 months (1/27 mice), with the prevalence of frailty increasing thereafter. At 17 months, 11.1% of the mice were pre-frail and by 26 months peaked at 36.9%. The percentage of frail mice progressively increased up to 66.7% at 32 months. Non-frail mice lived to 29 months whereas frail/pre-frail mice lived only to 26 months (p = .04). In closing, using a mouse frailty phenotype, we are able to identify that the prevalence of frailty in female mice increases across the life span and accurately predicts mortality. Together, this frailty phenotype has the potential to yield information about the underlying mechanisms contributing to frailty.

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