| Disease | THE EFFECTS OF LOW DIETARTY BETA-CAROTENE-I LEVELS ON SERUM CONCNS. OF LUTROPIN PREGNENOLONE, 17-ALPHA-HYDROXYPREGNENOLONE PROGESTERONE, 17-ALPHA-HYDROXYPROGESTERONE ANDROSTENDIONE, DEHYDROEPIANDROSTERONE TESTOSTERONE, AND ESTRADIOL AS WELL AS
ON VITAMIN A AND E. I AND CHOLESTEROL WERE EXAMINED IN NONLACTATING COWS. THE EXPERIMENT COMPRISED 1 COMPLETE ESTROUS CYCLE PER ANIMAL DURING A PERIOD OF I DEPLETION (50-60 DAYS), OF I SUBITITUTION (30 DAYS), AND A SUBSEQUENT CONTROL PHASE (22 DAYS).
IN THE COURSE OF THE I SUBSTITUTION PHASE I ANIMAL SHOWED A DELAY IN THE CORPUS LUTEUM DEVELOPMENT, WHEREAS DURING THE I DEPLETION PHASE, SIGNS OF GYNECOL. DISORDERS (VAGUE EXTERNAL ESTRUS SYMPTOMS, ENDOMETRITIS, PERSISTENCE OF CORPUS LUTEUM)
WERE OBSD. IN OTHERS. MEAN ESTRUS DURATION LASTED LONGER DURING THE I DEPLETION PHASE, SIGNS OF GYNECOL. DISORDERS (VAGUE EXTERNAL ESTRUS SYMPTOMS, ENDOMETRITIS, PERSISTENCE OF CORPUS LUTEUM) WERE OBSD. IN OTHERS. MEAN ESTRUS DURATION LASTED
LONGER DURING THE I DEPLETION PHASE THAN DURING THE SUBSTITUTION PHASE OF THE COMPARATIVE CONTROL PHASE. IN THE COMPARISON TO THE SERUM CONCNS. MEASURED THROUGHOUT THE I SUBSTITUTION AND CONTROL PHASE TESTOSTERONE (DURING THE COMPLETE ESTROUS
CYCLE) AND ESTRADIOL VALUES (DURING THE 44 H PRECEEDING UVULATION) WERE ELEVATED IN THE COURST OF THE I DEPLETION PERIOD. DURING THIS PERIOD THE TIME BETWEEN LUTROPIN RELEASE AND SUBSEQUENT OVULATION WAS MARKEDLY LENGHTENED IN SOME OF THE
ANIMALS ALTHOUGH NOT TO A SIGNIFICANT EXTENT. THUS, I DEFICIENCY STATES IN COWS MAY LEAD TO A DISTURBANCE OF THE PHYSIOL. FOLLICULAR STEROID HORMONE PRODN. WHICH THEN CAUSES THE OSB. CLIN. CHANGES. |