THE EFFECT OF COLD ACCLIMATION ON THE SIZE OF ORGANS AND TISSUES OF THE RAT, WITH SPECIAL REFERENCE TO MODES OF EXPRESSION OF RESULTS

1958 ◽  
Vol 36 (2) ◽  
pp. 209-216 ◽  
Author(s):  
O. Heroux ◽  
N. T. Gridgeman
Keyword(s):  
Experimental Data ◽  
Body Weight ◽  
Special Reference ◽  
Cold Acclimation ◽  
Muscle Mass ◽  
Cold Adaptation ◽  
Organ Weight ◽  
Organ Weights ◽  
White Rats ◽  
Body Weights

In experiments in which two groups of animals of different mean body weight are compared, individual organ weights of the animals can be expressed as absolute weights, as fractional weights, or as absolute weights statistically regressed onto constant body weights. The second, and commonest, mode of expression involves the assumption that the part is directly proportional to the whole, and this is shown to be unlikely for all organs except the muscle mass. Practical as well as theoretical justifications for the use of regressed weights (which utilize the actual slope of the line relating the organ weight to the whole) are given.The experimental data are from white rats kept for 4 weeks in a warm (30 °C.) or a cold (6 °C.) environment. It is shown that cold adaptation had no effect on brain, genitals, and lung weights, but that it reduced the growth of muscle, pelt, fat, skeleton, spleen, and thymus, and that it hypertrophied the liver, intestine, kidney, heart, and adrenals. Apparently cold acclimated rats are smaller than the controls mainly because they have a smaller muscle mass.

THE EFFECT OF COLD ACCLIMATION ON THE SIZE OF ORGANS AND TISSUES OF THE RAT, WITH SPECIAL REFERENCE TO MODES OF EXPRESSION OF RESULTS

1958 ◽  
Vol 36 (1) ◽  
pp. 209-216 ◽  
Author(s):  
O. Heroux ◽  
N. T. Gridgeman
Keyword(s):  
Experimental Data ◽  
Body Weight ◽  
Special Reference ◽  
Cold Acclimation ◽  
Muscle Mass ◽  
Cold Adaptation ◽  
Organ Weight ◽  
Organ Weights ◽  
White Rats ◽  
Body Weights

In experiments in which two groups of animals of different mean body weight are compared, individual organ weights of the animals can be expressed as absolute weights, as fractional weights, or as absolute weights statistically regressed onto constant body weights. The second, and commonest, mode of expression involves the assumption that the part is directly proportional to the whole, and this is shown to be unlikely for all organs except the muscle mass. Practical as well as theoretical justifications for the use of regressed weights (which utilize the actual slope of the line relating the organ weight to the whole) are given.The experimental data are from white rats kept for 4 weeks in a warm (30 °C.) or a cold (6 °C.) environment. It is shown that cold adaptation had no effect on brain, genitals, and lung weights, but that it reduced the growth of muscle, pelt, fat, skeleton, spleen, and thymus, and that it hypertrophied the liver, intestine, kidney, heart, and adrenals. Apparently cold acclimated rats are smaller than the controls mainly because they have a smaller muscle mass.

scholarly journals Evaluation of 2'fucosyllactose and Bifidobacterium longum subsp. infantis Supplementation to Formula on Growth, Organ Weights, and Intestinal Development of Piglets

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 789-789
Author(s):  
Marcia Monaco ◽  
Victoria Daniels ◽  
Mei Wang ◽  
Johanna Hirvonen ◽  
Henrik Max Jensen ◽  
...  
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Fixed Effects ◽  
Dry Matter ◽  
Bifidobacterium Longum ◽  
Milk Replacer ◽  
Intestinal Development ◽  
Organ Weights ◽  
Body Weights ◽  
The Impact

Abstract Objectives Human milk contains both prebiotic oligosaccharides and live bacteria, which are thought to bring health benefits to breastfed infants. Herein, we investigated the impact of formula supplementation with 2'-fucosyllactose (2'FL) and Bifidobacterium longum subsp. infantis (Bi-26) alone or in combination on growth, organ weights, and intestinal development of neonatal piglets. Methods Two-day-old intact male piglets (N = 53) were randomized to be fed a nutritionally-adequate milk replacer ad libitum without (CON) or with 1.0 g/L 2'FL (FL). Pigs were further stratified to receive either 12% glycerol solution alone or Bi-26 (109 CFU) in glycerol orally once daily (BI and FLBI). Body weights and food intake were monitored from postnatal day (PND) 2 to 33/34. On PND 34/35, animals were euthanized, intestine, liver and brain weights were assessed, and intestinal samples were collected for morphological analyses and disaccharidase activity. Dry matter of intestinal contents was also measured. Growth and food intake were analyzed as a 3-way, repeated-measures ANOVA with fixed effects of prebiotic, probiotic, and day, whereas all other variables were analyzed by a 2-way ANOVA with fixed effects of prebiotic and probiotic. Level of significance was set at P ≤ 0.05 and trends are reported at 0.05 > P < 0.1. Results All diets were well tolerated and food intake did not differ among the treatment groups. Daily body weights were affected by 2’FL, Bi26, and day, but no interaction was observed. However, there was a trend (p = 0.075) for greater body weight gain in CON vs. all other groups. No differences were observed for intestine, liver, or brain weight per kg body weight, jejunal or ileal lactase or sucrase activities, or fecal dry matter among the groups. Histomorphological outcomes in jejunum, ileum, and ascending colon were similar in all groups, except for a trend (p = 0.069) for larger ileal crypt volume in FL vs. CON piglets. Conclusions The addition of 2'FL and/or Bi-26 to milk replacer supported piglet growth with no detrimental effects on body and organ weights, or intestinal structure and function. Funding Sources DuPont Nutrition & Biosciences.

scholarly journals Determining organ weight toxicity with Bayesian causal models: Improving on the analysis of relative organ weights

2019 ◽  
Author(s):  
Stanley E. Lazic ◽  
Elizaveta Semenova ◽  
Dominic P. Williams
Keyword(s):  
Body Weight ◽  
Multiple Testing ◽  
Weight Ratio ◽  
Organ Damage ◽  
Organ Weight ◽  
Analysis Of Covariance ◽  
Toxicity Tests ◽  
Weight Changes ◽  
Organ Weights ◽  
Chemically Induced

AbstractRegulatory authorities require animal toxicity tests for new chemical entities. Organ weight changes are accepted as a sensitive indicator of chemically induced organ damage, but can be difficult to interpret because changes in organ weight might reflect chemically-induced changes in overall body weight. A common solution is to calculate the relative organ weight (organ to body weight ratio), but this inadequately controls for the dependence on body weight – a point made by statisticians for decades, but which has not been widely adopted. The recommended solution is an analysis of covariance (ANCOVA), but it is rarely used, possibly because both the method of statistical correction and the interpretation of the output may be unclear to those with minimal statistical training. Using relative organ weights can easily lead to incorrect conclusions, resulting in poor decisions, wasted resources, and an ethically questionable use of animals. We propose to cast the problem into a causal modelling framework as it directly assesses questions of scientific interest, the results are easy to interpret, and the analysis is simple to perform with freely available software. Furthermore, by taking a Bayesian approach we can model unequal variances, control for multiple testing, and directly provide evidence of safety.

WEIGHTS AND COMPOSITION OF MUSCLES OF WARM- AND COLD-ACCLIMATED RATS

1958 ◽  
Vol 36 (3) ◽  
pp. 289-293 ◽  
Author(s):  
O. Heroux
Keyword(s):  
Connective Tissue ◽  
Cold Acclimation ◽  
Muscle Mass ◽  
Cross Sections ◽  
Muscle Fibers ◽  
Protein Deposition ◽  
Content Difference ◽  
White Rats ◽  
Gastrocnemius Muscles ◽  
Exposure Measurements

After cold acclimation at 6 °C. white rats have a smaller muscle mass than control animals of the same age kept at 30 °C. Water and protein determinations in soleus and gastrocnemius muscles as well as in the whole muscular mass revealed that the reduction in the muscle mass after cold acclimation is a real tissue difference due to a reduced protein deposition and not only a water content difference. Apparently red and white fibers are equally affected in their growth by the prolonged cold exposure. Measurements of number and size of muscle fibers in soleus cross sections strongly suggest that protein deposition had been reduced in the same proportion in both muscle fibers and connective tissue.

Oral (Drinking Water) Two-Generation Reproductive Toxicity Study of Dibromoacetic Acid (DBA) in Rats

2002 ◽  
Vol 21 (4) ◽  
pp. 237-276 ◽  
Author(s):  
M. S. Christian ◽  
R. G. York ◽  
A. M. Hoberman ◽  
J. Frazee ◽  
L. C. Fisher ◽  
...  
Keyword(s):  
Drinking Water ◽  
Body Weight ◽  
Female Rats ◽  
Male Rats ◽  
Feed Consumption ◽  
Organ Weights ◽  
Body Weights ◽  
Group Generation ◽  
Generation Male ◽  
F1 Generation

In a two-generation study of dibromoacetic acid (DBA), Crl SD rats (30 rats/sex/group/generation) were provided DBA in drinking water at 0 (reverse osmosis-deionized water), 50,250, and 650 ppm (0,4.4 to 11.6,22.4 to 55.6, and 52.4 to 132.0 mg/kg/day, respectively; human intake approximates 0.1 μg/kg/day [0.0001 mg/kg/day]). Observations included viability, clinical signs, water and feed consumption, body and organ weights, histopathology, and reproductive parameters (mating, fertility, abortions, premature deliveries, durations of gestation, litter sizes, sex ratios and viabilities, maternal behaviors, reproductive organ weights, sperm parameters and implantation sites, sexual maturation). Histopathological evaluations were performed on at least 10 P and F1 rats/sex at 0 and 650 ppm (gross lesions, testes, intact epididymis; 10 F1 dams at 0, 250, and 650 ppm for primordial follicles). Developmental observations included implantations, pup numbers, sexes, viabilities, body weights, morphology, and reproductive performance. At 50 ppm and higher, both sexes and generations had increased absolute and relative liver and kidneys weights, and female rats in both generations had reduced absolute and relative adrenal weights; adrenal changes were probably associated with physiological changes in water balance. The livers and kidneys (10/sex/group/generation) had no histopathological changes. Other minimal effects at 50 ppm were reduced water consumption and a transient reduction in body weight. At 250 and 650 ppm, DBA reduced parental water consumption, body weight gains, body weights, feed consumption, and pup body weights. P and F1 generation male rats at 250 and 650 ppm had altered sperm production (retained step 19 spermatids in stages IX and X tubules sometimes associated with residual bodies) and some epididymal tubule changes (increased amounts of exfoliated spermatogenic cells/residual bodies in epididymal tubules, atrophy, and hypospermia), although inconsistently and at much lower incidences. Unilateral abnormalities of the epididymis (small or absent epididymis) at 650 ppm in four F1 generation male rats were considered reproductive tract malformations. The no-observable-adverse-effect level (NOAEL) and reproductive and developmental NOAELs for DBA were at least 50 ppm (4.5 to 11.6 mg/kg/day), 45,000 to 116,000 times the human adult exposure level. Reproductive and developmental effects did not occur in female rats exposed to DBA concentrations as high as 650 ppm. Based on the high multiples of human exposure required to produce effects in male rats, DBA should not be identified as a human reproductive or developmental risk.

scholarly journals Multiple-trait QTL mapping for body and organ weights in a cross between NMRI8 and DBA/2 mice

2007 ◽  
Vol 89 (1) ◽  
pp. 47-59 ◽  
Author(s):  
CHRISTINA NEUSCHL ◽  
GUDRUN A. BROCKMANN ◽  
SARA A. KNOTT
Keyword(s):  
Body Weight ◽  
Abdominal Fat ◽  
Multiple Trait ◽  
Organ Weights ◽  
Lean Control ◽  
Genome Wide ◽  
Body Weights ◽  
Inner Organs ◽  
Liver And Kidney ◽  
Parental Lines

Multiple-trait analyses have been shown to improve the detection of quantitative trait loci (QTLs) with multiple effects. Here we applied a multiple-trait approach on obesity- and growth-related traits that were surveyed in 275 F2 mice generated from an intercross between the high body weight selected line NMRI8 and DBA/2 as lean control. The parental lines differed 2·5-fold in body weight at the age of 6 weeks. Within the F2 population, the correlations between body weight and weights of abdominal fat weight, muscle, liver and kidney at the age of 6 weeks were about 0·8. A least squares multiple-trait QTL analysis was performed on these data to understand more precisely the cause of the genetic correlation between body weight, body composition traits and weights of inner organs. Regions on Chr 1, 2, 7 and 14 for body weights at different early ages and regions on Chr 1, 2, 4, 7, 14, 17 and 19 for organ weights at 6 weeks were found to have significant multiple effects at the genome-wide level.

ORGAN WEIGHT – BODY WEIGHT RELATIONS IN THE FAMILY MUSTELIDAE: THE MINK (MUSTELA VISON)

1965 ◽  
Vol 43 (1) ◽  
pp. 55-68 ◽  
Author(s):  
A. J. Wood ◽  
I. McT. Cowan ◽  
M. J. Daniel
Keyword(s):  
Body Weight ◽  
Mustela Vison ◽  
Organ Weight ◽  
The Body ◽  
Heart Weight ◽  
Organ Weights ◽  
The Family ◽  
Independent Variable

The relation between certain of the organs and the body weight of ranch raised mink has been examined. The lethal agent used for killing the mink is shown to affect the relative weights of the organs studied. The unsuitability of body weight as an independent variable against which to express organ weights is discussed and it is suggested that heart weight may be a more useful base.

WEIGHTS AND COMPOSITION OF MUSCLES OF WARM- AND COLD-ACCLIMATED RATS

1958 ◽  
Vol 36 (1) ◽  
pp. 289-293 ◽  
Author(s):  
O. Heroux
Keyword(s):  
Connective Tissue ◽  
Cold Acclimation ◽  
Muscle Mass ◽  
Cross Sections ◽  
Muscle Fibers ◽  
Protein Deposition ◽  
Content Difference ◽  
White Rats ◽  
Gastrocnemius Muscles ◽  
Exposure Measurements

After cold acclimation at 6 °C. white rats have a smaller muscle mass than control animals of the same age kept at 30 °C. Water and protein determinations in soleus and gastrocnemius muscles as well as in the whole muscular mass revealed that the reduction in the muscle mass after cold acclimation is a real tissue difference due to a reduced protein deposition and not only a water content difference. Apparently red and white fibers are equally affected in their growth by the prolonged cold exposure. Measurements of number and size of muscle fibers in soleus cross sections strongly suggest that protein deposition had been reduced in the same proportion in both muscle fibers and connective tissue.

RUMEN MOTILITY RESPONSES TO ADRENALINE AND NORADRENALINE AND ORGAN WEIGHTS OF WARM- AND COLD-ACCLIMATED SHEEP

1982 ◽  
Vol 62 (3) ◽  
pp. 777-786 ◽  
Author(s):  
A. D. GRAHAM ◽  
A. M. NICOL ◽  
R. J. CHRISTOPHERSON
Keyword(s):  
Small Intestine ◽  
Key Words ◽  
Cold Acclimation ◽  
Organ Weight ◽  
Acclimation Temperature ◽  
Inhibitory Effects ◽  
Internal Organs ◽  
Organ Weights ◽  
Dose Rates

The rumen motility responses to 2.5 h adrenaline (A) and noradrenaline (NA) intrajugular infusions at 0, 0.15, 0.30, 0.60 and 0.90 μg∙kg−1∙min−1 were studied in 10 shorn wethers which had been acclimated for 4–8 wk to either a warm (19–24 °C) or cold (8–13 °C) environment. Preinfusion rumen motility was not significantly influenced by acclimation temperature. Adrenaline infusions at the highest dose rates depressed motility in both warm-acclimated (WA) and cold-acclimated (CA) sheep and during the final 90 min of infusion the inhibition appeared greater in the WA sheep. Noradrenaline resulted in a depression of two contractions per hour in rumen motility of WA sheep but an increase of five contractions per hour in CA sheep. The results suggest that the CA sheep were resistent to the inhibitory effects of catecholamines on rumen motility. Six WA and six CA sheep were sacrificed and internal organs and gastrointestinal content weights were compared. Cold acclimation was associated with a significant increase in the weight of the liver, kidneys, reticulorumen and small intestine and of the content of the colon. Because CA sheep were fed 800 g more feed per day than WA sheep the effect of cold acclimation on organ and organ content weights cannot be separated from the effect that the increase in intake alone might have had. Key words: Adrenaline, noradrenaline, rumen motility, sheep, cold acclimation, organ weight

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