bSTH and IGF-I levels in blood and milk of black and white dairy cows before and after application of recombinantly derived bovine somatotropin.
In an 8 week trial period six black and white dairy cows were injected with Optiflex, a slow release formulation of recombinantly derived bovine somatotropin (BST). Three cows each were injected at two-weeks (BST-14) or four weeks (BST-28) intervals. The dosage was 640 mg BST per injection. Average milk yield increased by 18.3% and 13.8% in groups BST-14 and BST-28 respectively. Blood plasma levels of bSTH and IGF-I increased till day 10 post-injection; thereafter they declined, except IGF-I levels in group BST-14 which persisted continuously elevated with minor variations. No bSTH above detection level could be assayed in the milk of treated animals. The IGF-I level in milk was slightly elevated after BST-application but stayed within the normal range.
Mielke
H
H
Department of Animal Physiology, Karl-Marx-University, Leipzig, GDR.
Lochmann
G
G
Simon
I
I
Bier
H
H
Jahreis
G
G
Hesse
V
V
Gallowitsch
F
F
D000818:Animals; D002417:Cattle / Q000378:metabolism*; D005260:Female; D013006:Growth Hormone / Q000032:analysis / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007774:Lactation / Q000187:drug effects; D008892:Milk / Q000737:chemistry*; D011994:Recombinant Proteins / Q000494:pharmacology
D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone