Short communication: Effect of maternal heat stress in late gestation on blood hormones and metabolites of newborn calves.
Maternal heat stress alters immune function of the offspring, as well as metabolism and future lactational performance, but its effect on the hormonal and metabolic responses of the neonate immediately after birth is still not clear. The objective of this study was to investigate the blood profiles of hormones and metabolites of calves born to cows that were cooled (CL) or heat-stressed (HS) during the dry period. Within 2 h after birth, but before colostrum feeding, blood samples were collected from calves [18 bulls (HS: n=10; CL: n=8) and 20 heifers (HS: n=10; CL: n=10)] born to CL or HS dry cows, and hematocrit and plasma concentrations of total protein, prolactin, insulin-like growth factor-I, insulin, glucose, nonesterified fatty acid, and β-hydroxybutyrate were measured. Compared with CL, HS calves had lower hematocrit and tended to have lower plasma concentrations of insulin, prolactin, and insulin-like growth factor-I. However, maternal heat stress had no effect on plasma levels of total protein, glucose, fatty acid, and β-hydroxybutyrate immediately after birth. These results suggest that maternal heat stress desensitizes a calf's stress response and alters the fetal development by reducing the secretion of insulin-like growth factor-I, prolactin, and insulin.
College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China, 163319; Department of Animal and Dairy Science, University of Georgia, Tifton 31793.
J-R
JR
Guo
Department of Animal and Dairy Science, University of Georgia, Tifton 31793.
A P A
APA
Monteiro
Department of Animal and Dairy Science, University of Georgia, Tifton 31793.
X-S
XS
Weng
Department of Animal Sciences, University of Florida, Gainesville 32611.
B M
BM
Ahmed
Department of Animal Sciences, University of Florida, Gainesville 32611.
J
J
Laporta
Department of Animal Sciences, University of Florida, Gainesville 32611.
M J
MJ
Hayen
Department of Animal Sciences, University of Florida, Gainesville 32611.
G E
GE
Dahl
Department of Animal and Dairy Science, University of Georgia, Tifton 31793.
J K
JK
Bernard
Department of Animal and Dairy Science, University of Georgia, Tifton 31793. Electronic address: stao@uga.edu.
S
S
Tao
D020155:3-Hydroxybutyric Acid; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002417:Cattle; D002418:Cattle Diseases / Q000378:metabolism; D003126:Colostrum / Q000276:immunology; D005260:Female; D018882:Heat Stress Disorders / Q000378:metabolism / Q000662:veterinary*; D006358:Hot Temperature; D008297:Male
D020155:3-Hydroxybutyric Acid
dairy calves; heat stress; hormones