Evaluation of oral administration of cortisol as a model for prenatal stress in pregnant sows.
OBJECTIVE
To design a treatment that increases plasma corticosteroid concentrations to mimic prenatal stress in pregnant sows.


METHODS
24 pregnant sows.


METHODS
Sows were assigned to 1 of 4 treatment groups; treatment consisted of twice-daily oral administration of a placebo or 20, 60, or 180 mg of hydrocortisone acetate (HCA)/sow from 7 to 11 weeks of gestation. Blood and saliva samples for determination of cortisol concentrations were obtained hourly on treatment days 3 and 25 and twice weekly for the remainder of the treatment period. The WBC, neutrophil, and lymphocyte counts and concentrations of interleukin (IL)-2 and IL-4 were determined on 4 days during treatment. Litter characteristics were recorded.


RESULTS
Plasma and salivary cortisol concentrations were significantly increased in sows that received 60 or 180 mg of HCA (0.30 to 0.37 mg/kg and 0.95 to 1.15 mg/kg, respectively), compared with control sows. Except for the second day of treatment, the number of WBCs and the IL-2:IL-4 ratio did not differ among treatment groups. The neutrophil-to-lymphocyte ratio was significantly higher in sows that received 180 mg of HCA. Gestation duration was significantly shorter in sows that received 180 mg of HCA.


CONCLUSIONS
Oral administration of 60 mg of HCA is suitable to increase plasma and salivary cortisol concentrations in pregnant sows in a controlled manner to concentrations comparable to concentrations detected after psychologic stressors. This model seems to be suitable to study the effects of increased maternal corticosteroid concentrations on young pig behavior, physiologic variables, and development.
Kranendonk
Godelieve
G
Section of Foetal and Perinatal Biology, Department of Farm Animal Health, Faculty of Veterinary Medicine, University of Utrecht, Yalelaan 7, 3584 CL Utrecht, The Netherlands.
Hopster
Hans
H
van Eerdenburg
Frank
F
van Reenen
Kees
K
Fillerup
Maaike
M
de Groot
Johanna
J
Korte
Mechiel
M
Taverne
Marcel
M
D000284:Administration, Oral; D000818:Animals; D002940:Circadian Rhythm; D005260:Female; D006854:Hydrocortisone / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012469:Salivary Glands; D013312:Stress, Physiological / Q000139:chemically induced / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000139:chemically induced*
D006854:Hydrocortisone