EFFECT OF CONFINEMENT ON THE CIRCADIAN RHYTHM OF OVINE CORTISOL

in Journal of Endocrinology
Authors:
D. C. HOLLEY
Search for other papers by D. C. HOLLEY in
Current site
Google Scholar
PubMed
Close
,
D. A. BECKMAN
Search for other papers by D. A. BECKMAN in
Current site
Google Scholar
PubMed
Close
, and
J. W. EVANS
Search for other papers by J. W. EVANS in
Current site
Google Scholar
PubMed
Close
Restricted access
Rent on DeepDyve

Sign up for journal news

Department of Animal Science, University of California, Davis, California 95616, U.S.A.

(Received 8 October 1974)

Few studies have dealt with diurnal cortisol rhythm in sheep (McNatty, Cashmore & Young, 1972; McNatty & Young, 1973). The present results elucidate further the circadian rhythm of ovine plasma cortisol and describe the effect of sudden and continuous cage restraint.

Experimental methods and conditions were reported in detail by Holley & Evans (1974). Six mature rams were sampled at 4 h intervals for 32 days. On day 17 the animals were placed singly in small cages. Throughout the experiment the sheep received lucerne pellets at 16.00 h and the lighting schedule was maintained at 14 h light: 10 h darkness. Plasma cortisol was determined in duplicate without correction for other steroids as described by Bassett & Hinks (1969) and adjusted for extraction efficiency.

Fig. 1. Daily percentage variations (means ± s.e.m.) in plasma cortisol

 

  • Collapse
  • Expand