Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-09T09:12:47.099Z Has data issue: false hasContentIssue false

Evaporative cooling in fowls

Published online by Cambridge University Press:  27 March 2009

J. C. D. Hutchinson
Affiliation:
A.R.C. Poultry Research Centre, King's Buildings, Edinburgh

Extract

Part I

1. Reasons are given for expressing the evaporative loss of the resting fowl in the following way:

where C is a constant, f(tr) is a function of rectal temperature, ps is the vapour pressure of a saturated atmosphere at the temperature of the evaporative surfaces, and pa is the vapour pressure of the ambient air.

2. It was found that for practical physiological purposes the rectal temperature may be taken as that of evaporation, from which ps, is deduced. The real temperature of evaporation is probably a few degrees below this, as would be expected.

3. It is concluded from this, that atmospheric humidity hinders the evaporative cooling of fowls less than that of men. Therefore, a farmer cannot estimate the comfort of his fowls in hot weather from his own subjective impressions. The experiments also explain theoretically, why evaporative coolers for poultry houses are successful in practice.

PART II

1. The evaporative loss over a wide range of rectal temperature is plotted in Fig. 1. By applying formula (ii) it was possible to prepare curves for 28 and 5 mm. Hg atmospheric vapour pressure. These vapour pressures are near the extremes of absolute humidity, which fowls naturally encounter in hot climates. Brown Leghorns were used, and it is pointed out that the results with other breeds might not be quite the same.

2. It was calculated that part of the increase in evaporative cooling in hyperthermia is due to the rise in temperature of evaporation. At high rectal temperatures its importance is comparable with that of increased pulmonary ventilation.

3. There was no significant sex difference in the relation between evaporative loss and rectal temperature (Fig. 2).

4. The maximum possible evaporative cooling of fowls in equilibrium with their environment was 41 Kg.cal./sq.m./hr. at a humidity of 28 mm. Hg atmospheric vapour pressure and 64 Kg.cal./sq.m./hr. at 5 mm. This is much less than the maximum attained by man and somewhat less than that of the dog. Although evaporation per unit surface area was less than in the cow, it was much the same in relation to metabolic requirements.

5. Next, certain discrepancies are considered in the relation between rectal temperature and evaporative loss (Tables 3–5). At rectal temperatures near the panting threshold evaporation was found to be greater at high air temperatures and during the night. For the night tests fragmentary data only were available. These findings are tentatively attributed to a lower normal body temperature, which lowered the panting threshold.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1954

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Baldwin, S. P. & Kendeigh, S. C. (1932). Sci. Publ. Cleveland Mus. Nat. Hist. 3, 1.Google Scholar
Barott, H. G. & Pringle, E. M. (1941). J. Nutr. 22, 273.CrossRefGoogle Scholar
Beakley, W. R. (1953). Studies in the interchange of heat between the bovine and its environment. Thesis, University, Glasgow.Google Scholar
Benedict, F. G., Landauer, W. & Fox, E. L. (1932). Bull. Storrs Agric. Exp. Sta. no. 177.Google Scholar
Büttner, K. (1935). Biol. Zbl. 55, 356.Google Scholar
Canny, A. J. & Martin, C. J. (1939). J. Hyg., Camb., 39, 60.CrossRefGoogle Scholar
Dalton, J. (1802). Mem. Manchr Lit. Phil. Soc. 5, 535.Google Scholar
Eichna, L. W., Park, C. R., Nelson, N., Horvath, S. M. & Palmes, E. D. (1950). Amer. J. Physiol. 163, 585.CrossRefGoogle Scholar
Findlay, J. D. & Yang, S. H. (1950). J. Agric Sci. 40, 126.CrossRefGoogle Scholar
Glaser, E. M. & Lee, T. S. (1953). J. Physiol. 122, 59.CrossRefGoogle Scholar
Hammouda, M. (1933). J. Physiol. 77, 319.CrossRefGoogle Scholar
Hardy, J. D. (1949). Physiology of Heat Regulation and the Science of Clothing, edited by Newburgh, L. H., ch. 5. Philadelphia: Saunders.Google Scholar
Hutchinson, J. C. D. (1954 a). J. Agric. Sci. (in the Press.)Google Scholar
Hutchinson, J. C. D. (1954 b). Recent Advances in the Physiology of Farm Animals, ed. by Hammond, J., ch. 7. London: Butterworth.Google Scholar
Hutchinson, J. C. D. & Sykes, A. H. (1953). J. Agric. Sci. 43, 494.CrossRefGoogle Scholar
Kibler, H. H. & Brody, S. (1950). Res. Bull. Mo. Agric. Exp. sta. no. 461.Google Scholar
Kibler, H. H., Brody, S. & Worstell, D. M. (1949). Res. Bull. Mo. Agric. Exp. sta. no. 435.Google Scholar
Lee, D. H. K., Robinson, K. W., Yeates, N. T. M. & Scott, M. I. R. (1945). Poult. Sci. 24, 195.CrossRefGoogle Scholar
Nelson, N., Eichna, L. W., Horvath, S. M., Shelley, W. B. & Hatch, T. F. (1947). Amer. J. Physiol. 151, 626.CrossRefGoogle Scholar
Randall, W. C. (1943). Amer. J. Physiol. 139, 56.CrossRefGoogle Scholar
Riek, R. F. & Lee, D. H. K. (1948 a). J. Dairy Res. 15, 221.Google Scholar
Riek, R. F. & Lee, D. H. K. (1948 b). J. Dairy Res. 15, 227.CrossRefGoogle Scholar
Robinson, S. (1949). Physiology of Heat Regulation and the Science of Clothing, ed. by Newburgh, L. H., ch. 5. Philadelphia: Saunders.Google Scholar
Robinson, K. W. & Lee, D. H. K. (1946). Pap. Dep. Physiol. Univ. Qd, 1, no. 9.Google Scholar
Romijn, C. (1950). Tijdschr. Diergeneesk. 75, 719.Google Scholar
Saalfeld, E. F. Von (1936). Z. vergl. Physiol. 23, 727.CrossRefGoogle Scholar
Schierbeck, N. P. (1895). Arch. Hyg., Berl., 25, 196.Google Scholar
Shelley, W. B. & Hemmingway, A. (1940). Amer. J. Physiol. 129, 623.CrossRefGoogle Scholar
Simpson, S. & Galbraith, J. J. (1905). J. Physiol. 33, 225.CrossRefGoogle Scholar
Stefan, M. J. (1873). S. B. Akad. Wiss. Wien. (Math.-Naturwiss. Kl.), 68, 385.Google Scholar
Thompson, H. J., McCroskey, R. M. & Brody, S. (1949). Res. Bull. Mo. Agric. Exp. Sta. no. 451.Google Scholar
Thompson, H. J., McCroskey, R. M. & Brody, S. (1951). Res. Bull. Mo. Agric. Exp. Sta. no. 479.Google Scholar
Thompson, H. J., Worstell, D. M. & Brody, S. (1951). Res. Bull. Mo. Agric. Exp. Sta. no. 481.Google Scholar
Wilson, W. O. & Hillerman, J. P. (1952). Poult. Sci. 31, 847.CrossRefGoogle Scholar
Wilson, W. O., Hillerman, J. P. & Edwards, W. H. (1952). Poult. Sci. 31, 843.CrossRefGoogle Scholar
Yaglou, C. P. (1949). Physiology of Heat Regulation and the Science of Clothing, ed. by Newburgh, L. H., ch. 9. Philadelphia: Saunders.Google Scholar