Clinical evaluation of growth hormone secretion in cattle using insulin tolerance test.
Growth hormone secretion was evaluated in cattle. Clinically healthy bovine growth hormone (bGH) concentrations were 10.7 +/- 1.6 ng/ml in Holstein and 7.8 +/- 3.9 ng/ml in Japanese black cattle. The bGH concentration alternated at three-hour intervals, and tended to be higher at midnight and lower in the morning and before feeding. Insulin tolerance test (ITT) at an insulin dosage of 0.25 U/kg showed a significant increase of bGH concentration to 331 +/- 153% at 60 to 90 min after injection. In ITT applied to five under-growth calves of Japanese black cattle, the basal bGH concentrations were lower and peak values after insulin injection were shown to be significantly low. The ITT is useful for the clinical examination of bGH secretion in cattle.
Oguro
Masafumi
M
Department of Veterinary Internal Medicine, Kitasato University, Towada, Aomori, Japan.
Ishikawa
Hirotaka
H
Ohtsuka
Hiromichi
H
Hoshi
Fumio
F
Kawamura
Seiichi
S
D000818:Animals; D001835:Body Weight; D002417:Cattle / Q000254:growth & development / Q000378:metabolism*; D005260:Female; D013006:Growth Hormone / Q000096:biosynthesis / Q000378:metabolism*; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D013997:Time Factors
D007328:Insulin; D013006:Growth Hormone