Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Concentration of thyroid hormones and prolactin in dairy cattle serum and milk at three stages of lactation

Journal Article · · J. Dairy Sci.; (United States)
; ; ;
Eighteen lactating Holstein cows were used with six each in early, mid, and late lactation. Blood samples were obtained on 7 successive d. Blood serum and milk were measured by radioimmunoassay for thyroxine, 3,5,3'-triiodothyronine, and 3,3',5'-triiodothyronine. Prolactin was also measured in serum by radioimmunoassay. Serum thyroxine increased as lactation progressed and milk production declined (50, 55, and 62 ng/ml). Serum concentrations of triiodothyronine and reverse triiodothyronine were unchanged throughout lactation. Prolactin in serum declined as lactation advanced linearly (14.4, 11.8, and 10.5 ng/ml). Concentrations of thyroxine and triiodothyronine in milk declined significantly between early and mid but not mid and late lactation. Reverse triiodothyronine in milk did not change over the lactation. Serum triiodothyronine contained 1200 to 1300 pg/ml, whereas that in milk was 200 to 300 pg/ml. Reverse triiodothyronine was over 300 pg/ml in serum and only 80 to 90 pg/ml in milk. Amounts of thyroxine and triiodothyronine available to offspring from milk were calculated to be minor sources (4 to 5%) of total requirements for maintenance of metabolic function.
Research Organization:
Univ. of Missouri, Columbia
OSTI ID:
6020191
Journal Information:
J. Dairy Sci.; (United States), Journal Name: J. Dairy Sci.; (United States) Vol. 70:2; ISSN JDSCA
Country of Publication:
United States
Language:
English

Similar Records

Serum thyrotropin and thyroxine after thyrotropin releasing hormone in dairy cows fed varying amounts of iodine
Journal Article · Wed Jun 01 00:00:00 EDT 1977 · J. Dairy Sci.; (United States) · OSTI ID:7212779
Changes in serum prolactin and corticosterone and pituitary prolactin and hypothalamic catecholamines in response to immobilization stress
Conference · Fri Feb 28 23:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) · OSTI ID:5385657
L-lactate utilization by dairy goats
Thesis/Dissertation · Sat Dec 31 23:00:00 EST 1983 · OSTI ID:5220637

Related Subjects

553005* -- Agriculture & Food Technology-- Animal Husbandry-- (1987-)
60 APPLIED LIFE SCIENCES
AMINO ACIDS
ANIMALS
BIOLOGICAL MATERIALS
BLOOD SERUM
BODY FLUIDS
CARBOXYLIC ACIDS
CATTLE
COWS
DOMESTIC ANIMALS
FOOD
GONADOTROPINS
HORMONES
IMMUNOASSAY
IMMUNOLOGY
ISOTOPE APPLICATIONS
LACTATION
LTH
MAMMALS
MATERIALS
METABOLISM
MILK
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
PEPTIDE HORMONES
PITUITARY HORMONES
PRODUCTION
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RUMINANTS
THYROID HORMONES
THYROXINE
TRACER TECHNIQUES
TRIIODOTHYRONINE
VERTEBRATES