Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-03T05:36:17.293Z Has data issue: false hasContentIssue false

The efficiency of food utilization, digestibility of foodstuffs and energy expenditure of mice selected for large or small body size

Published online by Cambridge University Press:  14 April 2009

Ruth E. Fowler
Affiliation:
Institute of Animal Genetics, University of Edinburgh

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The efficiency of food utilization, the digestibility of foodstuffs, energy metabolism, and body activity have been studied in three lines of mice, one selected for large, another for small body size, and a third, control, line.

The gross efficiency of food utilization was highest in the large line, intermediate in the control line and lowest in the small line between 21 and approximately 35 days of age. During this period, gross efficiency declined in the large and control lines with increasing size and decreasing growth-rate, presumably due to an increase in maintenance costs in comparison with the weight gained. In the small line, the efficiency of food utilization increased up to 35 days of age but declined thereafter. The energetic efficiency (measured in Calories) was higher in the large than in the small line up to 4 weeks of age, i.e. when the growth-rate was high, and after 6 weeks of age, when fat was being deposited at an increased rate.

The increased efficiency of large mice was not entirely associated with a greater proportion of the ingested food being absorbed from the gut. Large mice absorbed a greater proportion of protein, though the difference was not sufficient to account for the large weight difference between the large and small lines.

The energy expenditure of mice of the large line was greater than that of the small line at all ages and similar for the same body weights. The reduced growth-rate of small mice was not due to abnormally high or low energy costs. There was no evidence that body activity determined or restricted the rate of growth in either line.

Mice selected for small size were phenotypically unlike pituitary dwarf mice, although the low nitrogen retention during the growing-period indicated a deficiency of some growth stimulus.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1962

References

REFERENCES

Benedict, F. G. & Lee, R. C. (1936). La production de chaleur de la souris. Etude de plusiers races de souris. Ann. Physiol. Physicochim. biol. 12, 9831064.Google Scholar
Brody, S. (1945). Bioenergetics and Growth. New York: Reinhold Publishing Corporation.Google Scholar
Dewar, A. D. & Newton, W. H. (1948 a). The determination of total metabolism in the mouse. Brit. J. Nutrit. 2, 123141.CrossRefGoogle ScholarPubMed
Dewar, A. D. & Newton, W. H. (1948 b). The relationship between food intake and respiratory quotient in mice. Brit. J. Nutrit. 2, 142145.CrossRefGoogle ScholarPubMed
Dickerson, G. E. (1947). Composition of hog carcasses as influenced by heritable differences in rate and economy of gain. Res. Bull. Ia agric. Exp. Sta. no. 354, 489524 (B).Google Scholar
Dickerson, G. E. & Grimes, J. C. (1947). Effectiveness of selection for efficiency of gain in Duroc swine. J. Anim. Sci. 6, 265287.CrossRefGoogle ScholarPubMed
Dickerson, G. E. & Gowen, J. W. (1947). Hereditary obesity and efficiency of food utilisation in mice. Science, 105, 496498.CrossRefGoogle ScholarPubMed
Elftman, H. & Wegelius, O. (1959). Anterior pituitary cytology of the dwarf mouse. Anat. Rec. 135, 4347.CrossRefGoogle ScholarPubMed
Falconer, D. S. (1953). Selection for large and small size in mice. J. Genet. 51, 470501.CrossRefGoogle Scholar
Fowler, R. E. (1958). The growth and carcass composition of strains of mice selected for large and small body size. J. agric. Sci. 51, 137148.CrossRefGoogle Scholar
Fowler, R. E. & Edwards, R. G. (1960). The fertility of mice selected for large or small body size. Genet. Res., Camb., 1, 393407.CrossRefGoogle Scholar
Goodale, H. D. (1938). A study of the inheritance of body weight in the albino mouse by selection. J. Hered. 29, 101112.CrossRefGoogle Scholar
Haldane, J. (1892). A new form of apparatus for measuring the respiratory exchange of animals. J. Physiol. 13, 419430.CrossRefGoogle ScholarPubMed
MacArthur, J. N. (1944). Genetics of body size and related characters. I. Selecting small and large races of the laboratory mouse. Amer. Nat. 78, 142157.CrossRefGoogle Scholar
Mayer, J. (1955). Mechanism of regulation of food intake and multiple etiology of obesity. Voeding, 16, 6288.Google Scholar
Morris, H. P., Palmer, L. S. & Kennedy, C. (1933). An experimental study of inheritance as a factor influencing food utilisation in the rat. Tech. Bull. Minn. Agric. Exp. Sta. no. 92, 56 pp.Google Scholar
Palmer, L. S., Kennedy, C., Calverley, C. E., Lohn, C. & Weswig, P. H. (1946). Genetic differences in the biochemistry and physiology influencing food utilization for growth in rats. Tech. Bull. Minn, agric. Exp. Sta. no. 176, 54 pp.Google Scholar
Schonholz, D. H. & Osborn, C. M. (1949). Temperature studies in dwarf mice. Anat. Rec. 105, 605 (Abstr.).Google Scholar
Widdowson, E. M. (1955). Assessment of energy value of human foods. Proc. Nutr. Soc. 14, 142154.CrossRefGoogle ScholarPubMed