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PubMed · 1659025

Adrenocortical function testing in dairy cows and its effect on milk yield.

J H van der Kolk·H J Breukink·T Wensing·J A Mol
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Abstract

Administration of 6IU synthetic ACTH1-24 intravenously to six Holstein-Friesian cows resulted in a cortisol peak concentration after 1 hour of 148 +/- 34.2 ng/ml. Basal plasma cortisol concentration (4.84 +/- 0.83 ng/ml) was reached 5 hours after ACTH injection. Until 7 days after ACTH administration no effect on milk yield was recorded. So it is concluded that a dose of 6 IU ACTH1-24 is sufficient for a conspicuous release of cortisol without any alteration in milk production. This dose can be used as a standard test for the evaluation of adrenocortical function in lactating cows when administered intravenously at 9 a.m. and when plasma samples for cortisol assay are collected just prior to administration and at 10 a.m.

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Adrenal CortexAdrenal Cortex Function TestsAdrenocorticotropic HormoneAnimalsCattleFemaleHydrocortisoneLactationMammary Glands, AnimalMilkJournal Article

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J H van der Kolk, H J Breukink, T Wensing, J A Mol. 1991. Adrenocortical function testing in dairy cows and its effect on milk yield.. https://doi.org/10.1080/01652176.1991.9694299

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