Changes in hormones, metabolites, and milk after treatment with sometribove (recombinant methionyl bST) in Deutsches Fleckvieh and German black and white cows.
Twelve second-lactation Deutsches Fleckvieh cows, (FV, a dual-purpose breed) and 12 German Black and White (BW, a dairy breed) were used to evaluate similarities and differences in the response to a prolonged-release formulation of sometribove (N-methionyl bovine somatotropin, bST). Cows were milked twice daily and fed a basic diet (70% corn silage, 30% alfalfa hay) ad libitum plus 1 kg of concentrate. Additionally, concentrates and supplements were offered at the rate of 1 kg for each 22 kg of milk produced above 12 kg/d. Six cows of each breed were treated s.c. with 500 mg of sometribove at 14-d intervals from wk 9 to 29 postpartum (pp). Blood was collected by jugular vein puncture once weekly from wk 7 to 33 pp and daily for 14 d after the first and last (11th) injection of bST. Somatotropin (ST), insulin-like growth factor I (IGF-I), insulin, thyroid hormones, nonesterified fatty acids (NEFA), liver enzymes, and blood metabolites were evaluated. During bST treatment, plasma ST increased significantly on d 7 in both breeds and then decreased on d 14 after injection. Plasma IGF-I was positively correlated with ST. Plasma NEFA were high on d 7 and decreased on d 14. In response to bST, the average milk yield increased for FV and BW cows by 5.1 kg/d (29.7%) and 5.0 kg/d (28%), respectively, and 4% fat-corrected milk (FCM) increased by 5.0 kg/d (28%) and 5.3 kg/d (19.9%), respectively. Milk content of fat, protein, lactose, number of somatic cells, and body weight were similar across treatments.(ABSTRACT TRUNCATED AT 250 WORDS)
Schams
D
D
Dept. of Physiol., Technical University of Munich-Weihenstephan, Freising, Germany.
Graf
F
F
Meyer
J
J
Graule
B
B
Mauthner
M
M
Wollny
C
C
D000818:Animals; D001947:Breeding; D002417:Cattle / Q000378:metabolism*; D003692:Delayed-Action Preparations; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D013006:Growth Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology; D006728:Hormones / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology*; D019382:Human Growth Hormone; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007774:Lactation / Q000187:drug effects*; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology; D015430:Weight Gain / Q000187:drug effects
D003692:Delayed-Action Preparations; D005230:Fatty Acids, Nonesterified; D006728:Hormones; D007328:Insulin; D011994:Recombinant Proteins; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone