scholarly journals Thermogenesis, aging and obesity in the LA Ntul/-cp (corpulent) rat

2021 ◽  
Vol 11 (2) ◽  
pp. 37-43 ◽  
Author(s):  
Orien L Tulp ◽  
George P Einstein
Keyword(s):  
Oxygen Consumption ◽  
Cold Exposure ◽  
Resting Metabolic Rate ◽  
Age Groups ◽  
Fold Increase ◽  
The Body ◽  
Metabolic Rates ◽  
Body Weights ◽  
Old Rats ◽  
Obese Phenotype

Obesity and mild to moderate impaired carbohydrate tolerance develops in the obese phenotype of the LA/Ntul//-cp (corpulent) rat strain by 6 weeks of age. Groups (n=12-20 rats/phenotype] of female congenic lean and obese LA/Ntul//-cp (corpulent) rats were fed ad libitum standardized Purina #5012 diet ad house water for 4, 14, or 24 months of age. Measures of Body weight (BW) and of resting oxygen consumption (RMR; VO2) at thermal neutrality and for up to 45 minutes of (4°C) spontaneous cold exposure, and norepinephrine-stimulated thermogenesis (100 ug. s.c.) were determined at each age. Body weights of lean rats increased only gradually during the study (p=n.s.), but weights of obese phenotype were ~2-fold greater at 4 months (p=<0.05), 14 months (p-<0.01), and ~3.5 to 4-fold greater at 24 months of age (p=<0.01). Resting metabolic rates in the lean phenotype trended to decrease modestly by 24 months (p=<0.05) and were greater than resting metabolic rates in the obese phenotype at all ages studied (p=<0.05). Cold exposure at 4°C resulted in a dramatic ~5-fold increase in the oxygen consumption after 5 minutes in 4-month-old rats, which subsided to ~2x resting metabolic rate within 15 minutes and remained constant thereafter in the lean phenotype. In 14-months old lean rats the increase in oxygen consumption at 5 minutes averaged ~4-fold increase over resting levels and returned to ~2x resting levels from 15 to 45 minutes 4°C exposure. In 24-month-old lean rats however, the cold induced increases in metabolism were markedly diminished to only ~3x resting metabolic rates at 5 minutes cold exposure but remained similar to the other lean age groups thereafter. In the obese phenotype, the peak responses at 5 minutes were lower than those of lean rats at 5 minutes in 4- and 14-month-old rats and were significantly impaired in 24-month-old rats at all times measured. Norepinephrine resulted in a >1.5-fold increase in oxygen consumption in the lean phenotype at all ages studied, while in obese rats norepinephrine resulted in a~1.4-fold increase in oxygen consumption at 4 months of age with non-significant ~1.1 to 1.2-fold increases at the two older ages. In both phenotypes, the resting and the norepinephrine-stimulated oxygen consumption responses tended to decrease with increasing age. The results of this study demonstrate that the body weights of the obese phenotype are significantly greater than their lean littermates throughout the age spectrum studied, and that both resting metabolic rates, 4°C cold, and norepinephrine-stimulated thermogenesis are decreased in the obese compared to the lean phenotype and become further decreased with advancing age

Prediction of body weights of Nellore sheep under field condition

2015 ◽  
Author(s):  
M. Rani ◽  
B. Ekambaram ◽  
B. Punya Kumari
Keyword(s):  
Body Weight ◽  
Body Length ◽  
Age Groups ◽  
The Body ◽  
Coefficient Of Determination ◽  
Regression Equations ◽  
Body Weights ◽  
Chest Girth ◽  
Males And Females ◽  
Nellore Sheep

Data on 1350 Nellore sheep of 2, 4, 6 and 8-teeth age, reared under field conditions in 12 mandals of Chittoor district of Andhra Pradesh were utilized for development of prediction equations and study the phenotypic association among body measurements and body weights. The coefficients of correlation between body weight with the height at withers, chest girth, paunch girth, hip width and body length were positive and high in magnitude in both males and females in majority of the age groups studied. Step-down regression equations were fitted to predict the body weight based on biometrical measurements at different ages. The height at withers, chest girth, paunch girth, hip width and body length have contributed significantly to the expression of body weights at the majority of the ages studied. High coefficient of determination (R2) value was observed in males at 6 and 8-teeth age as 88 per cent, while in females 50 per cent at 2-teeth age.

scholarly journals SUMMIT METABOLISM OF NEWBORN CALVES WITH AND WITHOUT COLOSTRUM FEEDING

1986 ◽  
Vol 66 (4) ◽  
pp. 937-944 ◽  
Author(s):  
M. OKAMOTO ◽  
J. B. ROBINSON ◽  
R. J. CHRISTOPHERSON ◽  
B. A. YOUNG
Keyword(s):  
Body Weight ◽  
Metabolic Rate ◽  
Rectal Temperature ◽  
Cold Water ◽  
Water Immersion ◽  
Resting Metabolic Rate ◽  
The Body ◽  
Metabolic Rates ◽  
Colostrum Feeding ◽  
Time Required

Resting and summit metabolic rates were measured in 13 newborn (2.5–15 h old) male Holstein calves exposed to warm and cold tempertures in a water immersion system. Six calves were bottle fed 1 kg of colostrum 30 min before the measurements commenced. In the remaining seven calves, colostrum was withheld until after the end of the measurement period. There were no significant effects of colostrum feeding on resting or summit metabolic rates or the time required for rectal temperature to drop to 35 °C when the calves were immersed in cold water. The time required for rectal temperature to drop to 35 °C increased as the body weight of the calves increased; for each kilogram additional body weight, cooling was delayed for an extra 2.9 min. The resting metabolic rate averaged for both feeding treatments was 2.0 ± 0.1 W kg−1 while mean rectal temperature was 39.1 ± 0.2 °C. Mean summit metabolic rate was 7.2 ± 0.4 W kg−1 and occurred at a mean rectal temperature of 35.4 ± 0.3 °C. The average ratio of the summit to resting metabolic rate was 3.7 ± 0.2. Cooling via water immersion was associated with increases in plasma levels of glucose and free fatty acids. The feeding of 1 kg of colostrum 30 min prior to exposure to acute cold did not improve the apparent resistance of the calves to hypothermia. Key words: Newborn calf, summit metabolism, cold tolerance

CHARACTERIZATION AND CONSERVATION OF THE MALPURA SHEEP BREED

1995 ◽  
Vol 16 ◽  
pp. 75-82
Author(s):  
S. C. Mehta ◽  
P. K. Vij ◽  
B. K. Joshi ◽  
R. Sahai ◽  
A. E. Nivsarkar
Keyword(s):  
Body Length ◽  
Age Groups ◽  
Morphological Characteristics ◽  
Tail Length ◽  
The Body ◽  
Body Measurements ◽  
Face Width ◽  
Body Weights ◽  
Face Length ◽  
Chest Girth

SUMMARYObservations were recorded on morphological characteristics, body weights and body measurements of 344 Malpura sheep belonging to nine age groups during a survey conducted in 18 randomly selected villages of three blocks of the Chittorgarh district of Rajastha. The body weights at birth, 1, 3, 6 and 9 months and adult weight averaged 3.3, 6.7±0.88, 12.9±0.71, 16.4±0.71, 21.0±1.00 and 31.4 kg respectively. Height, body length, chest girth, paunch girth, face length, face width, tail length and ear length of adult Malpura sheep averaged 63.6, 66.8, 77.1, 80.9, 20.7, 9.8, 30.3 and 6.3 cm respectively. Sex of the animal had significant effect on weight, height, body length and chest girth at 8 teeth stage. Phenotypic correlations of body weight with height, chest girth and paunch girth ranged from 0.76±0.04 to 0.88±0.03 and regression of weight on these body measurements ranged from 0.63±0.02 to 0.98±0.05.

scholarly journals PUBERAL DEVELOPMENT IN THE NIGERIAN DWARF SHEEP

2021 ◽  
Vol 7 (1) ◽  
pp. 71-76
Author(s):  
B. I. Orji ◽  
J. Steinbach
Keyword(s):  
Body Weight ◽  
Reproductive Tract ◽  
Age Groups ◽  
Reproductive Organs ◽  
The Body ◽  
Endocrine Function ◽  
Physiological Age ◽  
Body Weights ◽  
Pituitary Glands ◽  
Ram Lambs

Eleven ram lambs, all born between June and July (rainy season) were slaughtered at four age groups — 75, 100, 125 and 150 days. The body weights of animals prior to slaughter, the weights of the testes, the epididymis, the vesicular glands, the ampullae, the adrenals, the thyroids and the pituitary glands were determined and subjected to a step-wise multiple regression analysis using age or body weight as the independent variable. The weights of the reproductive organs – testes, epididymides, ampullae, vesicular glands - showed significantly higher correlation with the body weight than with the age, thus emphasizing the greater importance of the physiological age over the chronological age in the development of the body organs. The highest growth rate of the organs of the reproductive tract occurred during puberty and thus coincided with the enhanced endocrine function observed in ram lambs at this stage.

Winter bioenergetics of Rocky Mountain bighorn sheep

1978 ◽  
Vol 56 (11) ◽  
pp. 2388-2393 ◽  
Author(s):  
R. W. Chappel ◽  
R. J. Hudson
Keyword(s):  
Dry Matter ◽  
Resting Metabolic Rate ◽  
Rocky Mountain ◽  
Bighorn Sheep ◽  
Dry Matter Intake ◽  
Metabolic Rates ◽  
Critical Temperatures ◽  
Wind Speeds ◽  
Body Weights ◽  
Voluntary Intake

Changes in voluntary dry matter intake, body weight, and resting metabolic rates at 10 and −10 °C were measured in four adult Rocky Mountain bighorn sheep from October until May. Voluntary intake in mid-February decreased to 0.55 of that in mid-October. Body weights increased until January after which stasis or slight declines occurred. Resting metabolic rate at 10 °C fluctuated without a consistent pattern over winter. Resting metabolic rates at −10 °C were lowest in February and highest in May. The lower critical temperatures of fed animals in winter pelage were below −20 °C. As temperatures were lowered from −20 to −30 °C, metabolic rates increased 1.37- to 1.39-fold. Wind speeds from 4 to 8 m/s increased metabolic rates only at temperatures below −20 °C.

Effect of age on cold acclimation in rats: metabolic and behavioral responses

1991 ◽  
Vol 260 (2) ◽  
pp. R284-R289 ◽  
Author(s):  
T. L. Owen ◽  
R. L. Spencer ◽  
S. P. Duckles
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Cold Acclimation ◽  
Cold Exposure ◽  
Resting Metabolic Rate ◽  
Age Groups ◽  
Behavioral Responses ◽  
Mortality And Morbidity ◽  
Ambient Temperatures ◽  
Reduced Body

To determine whether senescence affects the metabolic and behavioral responses of rats to chronic cold exposure, 8- and 22-mo-old male Fischer 344 rats were studied before and after 6 wk of cold (6-10 degrees C) exposure. Measurements of body weight, food consumption, oxygen consumption, body temperature, and ambient temperature selection in a thermocline (7-37 degrees C linear gradient) were made at regular intervals throughout the acclimation period. Before acclimation, age groups differed significantly only by weight. During acclimation, older rats had increased mortality and morbidity below 10 degrees C. After acclimation at 10 degrees C, younger and older rats both selected cooler ambient temperatures (7 and 5 degrees C cooler than preacclimation, respectively), and older rats had a significantly greater decrease in body temperature in the thermocline. Both age groups increased resting metabolic rate at 25 degrees C with cold acclimation (16.5 and 10% increase for younger and older rats, respectively). This study indicates distinct differences in metabolic and behavioral responses of younger and older rats to cold acclimation. Chronic cold exposure is detrimental to thermoregulatory function in older rats, since it is not as effective in stimulating sustained increases in metabolic rate in older rats as in young adults and it leads to a preference for cooler ambient temperatures, resulting in increased heat loss and reduced body temperature.

Energetics of Sablefish, Anoplopoma fimbria, under Laboratory Conditions

1982 ◽  
Vol 39 (7) ◽  
pp. 1012-1020 ◽  
Author(s):  
Kathleen M. Sullivan ◽  
Kenneth L. Smith Jr.
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
Growth Rates ◽  
The Body ◽  
Fish Growth ◽  
Metabolic Rates ◽  
Anoplopoma Fimbria ◽  
Consumption Rates ◽  
Excretion Rates ◽  
Conversion Efficiencies

We measured respiration, growth, ingestion, and excretion rates for sablefish, Anoplopoma fimbria, collected off southern California at a depth of 500 m and maintained in the laboratory. We also measured the water, protein, and lipid content of white skeletal muscle in both laboratory-held and field fish. Sablefish fed a large ration (14% of wet body weight) every 7–10 d showed growth rates two to three times higher than known growth rates for field fish. On a reduced ration (4% of wet body weight) sablefish grew at rates similar to field fish, but white muscle composition varied significantly from field fish. Oxygen consumption rates under constant temperature conditions showed a decrease in the weight-specific oxygen consumption rates with increase in body weight, ranging from routine metabolic rates of 195.8 mg O2∙kg−1∙h−1 for a 0.25-kg fish to 60.8 mg O2∙kg−1∙h−1 for a 2.78-kg fish. Based on measurements of respiration and excretion, sablefish were estimated to have 162 d of energy stored in the body lipids and did not show signs of starvation stress with food deprivation up to 6 mo in the laboratory. Energy allocation shows very slow growth rates, low conversion efficiencies, and low metabolic rates as adjustments made to large, infrequent meals.Key words: physiological responses, benthopelagic fish, growth, metabolic rate, respiration, excretion

Cellular proliferation and UCP content in brown adipose tissue of cold-exposed aging Fischer 344 rats

1998 ◽  
Vol 274 (1) ◽  
pp. R196-R203 ◽  
Author(s):  
Maria Florez-Duquet ◽  
Barbara A. Horwitz ◽  
Roger B. McDonald
Keyword(s):  
Cell Proliferation ◽  
Cold Exposure ◽  
Fold Increase ◽  
Brown Fat ◽  
Male Rats ◽  
Nonshivering Thermogenesis ◽  
Fischer 344 ◽  
Brown Adipose ◽  
Igf I ◽  
Old Rats

Previous investigations have demonstrated that older vs. younger rats respond to cold exposure with blunted cold-induced nonshivering thermogenesis of brown adipose tissue (BAT). This reduction in nonshivering thermogenesis is associated with reduced mass and blunted nonshivering thermogenic capacity of BAT. The purpose of this study was to test the hypothesis that brown fat in 26-mo-old Fischer 344 (F344) male rats has an impaired capacity to respond to the trophic stimulus of chronic cold exposure with increases in cell number, mass, and uncoupling protein (UCP) content. To test this hypothesis, the response of BAT to chronic cold exposure was evaluated in young and old rats. We exposed 6-, 12-, and 26-mo-old F344 male rats to 10°C for 5 days and measured interscapular BAT (IBAT) mass, cell size and proliferation, and mitochondrial UCP1 content. Plasma concentrations of insulin-like growth factor I (IGF-I) and norepinephrine (NE) were also determined. The 26-mo-old rats did not increase IBAT mass, cell proliferation, or UCP1 content in response to chronic cold, whereas the 6-mo-old rats had a nearly 2-fold cold-induced increase in IBAT mass, a 26-fold increase in cell proliferation, and a 4-fold increase in UCP1 content. Cold exposure also produced an increase of 29, 19, and 20% in mature brown adipocyte cell size of the 6-, 12-, and 26-mo-old animals, respectively. Plasma levels of IGF-I were unaffected by cold at all ages, whereas NE levels were increased by the cold exposure and by increasing age. These data support the hypothesis that brown fat in old F344 rats does not respond to the trophic stimulus of chronic cold exposure to the same degree as younger animals. Moreover, these data indicate that the observed cold- or age-induced changes in levels of growth factors evaluated in this study were not associated with the lack of cold-induced preadipocyte proliferation or increased UCP1 in brown fat of the 26-mo-old rats.

THE EFFECT OF AGEING ON THE NUMBER OF THE ISLETS OF LANGERHANS IN THE RAT

1959 ◽  
Vol XXXII (I) ◽  
pp. 78-91 ◽  
Author(s):  
Bo Hellman
Keyword(s):  
Body Weight ◽  
Age Groups ◽  
The Body ◽  
Male Rats ◽  
Quantitative Relation ◽  
List Type ◽  
Positive Correlation ◽  
Islet Volume ◽  
Old Rats ◽  
Lower Size

ABSTRACT Information concerning the so called 'total number' of islets is inexact. The number of islets should instead be expressed as that number which exceeds a well defined and easily identifiable lower size boundary. Studies on the numerical distribution of the islets show, in a comparison between two animals, that while the same lower size limit must be set in each case, considerable latitude may be exercised in selecting its actual value without disturbing the results. In this investigation only those islets, whose diameter was equal to or exceeded 46.9 μ were counted. The effect of ageing on the number of islets has been studied in a total of 75 male rats, which were nourished on a diet well defined calorically. The rats were killed on the 1st, 5th, 21st, 100th and 480th days of life. The following observations were made: With increase in age there was a marked increase in the number of islets. The value in the oldest animals was on the average more than 13 times that in the new-born. If the number of islets is expressed in relation to the total body weight or the weights of liver or pancreas, the ratio is markedly reduced with increasing age. The 480 days old rats were, however, an exception, as the values for this age showed a statistically significant increase as compared with 100 days old rats. When plotted in a double logarithmic co-ordinate system the liver and pancreatic weights were linear functions of the body weight in all the age groups studied. The corresponding regression between the islet number and the body weight was, however, curvilinear, so that the rate of increase was initially slow (between 0–5 days) but between the two oldest groups (100 and 480 days) it approached that of the pancreatic and liver weights. In each age group there is a strongly positive correlation between the number of islets and the total islet volume. In most of the age groups there was statistical support for a positive correlation between body weight and number of islets. Within the different age groups a quantitative relation between the number of islets and the weight of the pancreas was not apparent after the common positive correlation with the body weight had been eliminated by calculating the partial correlations. The regular mathematical arrangement of the islet tissue makes it possible to determine the actual number of islets by only counting the number of islet section surfaces which exceed a certain defined size.

scholarly journals Effect of adrenalectomy and glycemic status on caloric efficiency and adiposity in the congenic LA/Ntul//-cp (corpulent) rat

2021 ◽  
Vol 11 (6) ◽  
pp. 168-176
Author(s):  
Orien L Tulp ◽  
Aftab R Awan ◽  
George P Einstein
Keyword(s):  
Caloric Intake ◽  
Fold Increase ◽  
Chow Diet ◽  
Treatment Schedule ◽  
Dietary Regimen ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose ◽  
Body Weights ◽  
Obese Rats ◽  
Obese Phenotype

Obesity develops in the obese phenotype of the congenic LA/Ntul//-cp (corpulent) rat strain by 6 weeks of age.1 To gain insight into the contributors to the expression of obesity in the obese phenotype of this strain, groups [n=12-20 rats/phenotype] of congenic male lean and obese LA/Ntul//-cp (corpulent) rats were fed an ad libitum standardized Purina chow diet (CHOW) from 6 to 12 weeks or age, and subgroups (n=6 rats / subgroup) were overfed with a highly palatable cafeteria diet (CAFÉ) from 9 to 12 weeks of age (WOA). A subgroup of obese rats (n=6) were subjected to bilateral adrenalectomy (ADX) at 6 WOA and followed the same dietary regimen and treatment schedule. BW of lean and obese animals were similar at 6 WOA and increased by 88% in lean phenotype and 281% in obese phenotype during the 6 weeks study, while in ADX obese rats, BW were similar at 6 and 9 WOA but BW increased to 2.5-fold above starting weights and 1.8-fold above 9-week weights between 9 and 12 WOA. The CAFE supplement was without significant effect on final body weights in the lean phenotypes, but was associated with significantly greater body weights at ages 9 and 12 WOA in the obese phenotype (p=<0.05) and in the obese-ADX at 12 WOA. CE (kcal/gram gain of BW per day) remained relatively constant in lean and obese-ADX rats throughout the study, but CE was more efficient in the obese phenotype at all ages studied and was more efficient with the CAFE supplement feeding regimen. Fasting I:G ratios at 12 weeks of age were 4.2-fold greater in obese than lean and were partially normalized in obese-ADX to 1.7-fold increase at 12 WOA. Relative adiposity of obese rats was 3.8-fold greater in obese than lean phenotype, with the greatest increase in the SQ depot. Resting VO2 (RMR) was lower in obese than lean rats at each age studied and was increased by ADX. Thermogenic interscapular brown adipose tissue (IBAT) mass was greater in obese and obese-ADX than lean rats. The results of this study indicate that CE is associated with the predisposition for the expression and development of adiposity in the obese phenotype of this strain and is associated with an increased I:G ratio and IBAT mass that is consistent with insulin resistance and an impaired capacity for energy expenditure and became normalized on the Chow but not the CAFE diet following ADX. These observations implicate likely multiple metabolic factors that contribute to a greater efficiency of energy storage, utilization and or energy conservation in the obese than in the lean phenotype of this strain and which is partially corrected in the obese phenotype by ADX. The metabolic impact of added caloric intake was associated with an additive impact on the CE of weight gain and adiposity in the obese phenotype of this congenic rodent strain and was partially corrected via ADX

Sign in / Sign up

Export Citation Format

Share Document