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Updated: Aug 17, 2026

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A Tissue Culture Model of Estrogen-producing Primary Bovine Granulosa Cells
Published on: September 6, 2018
Testosterone and libido in holstein bulls of various ages
Journal of Dairy Science
|November 1, 1976
Abstract:
Testosterone was measured by radio-immunoassay in the blood plasma collected from 197 and 195 Holstein bulls in the spring and fall seasons, respectively. Bulls ranged in age from 8 mo to 13.5 yr. The average value for spring was 8.0 ng/ml, higher than the value of 5.7 ng/ml in the fall. Also, there was a tendency for testosterone to increase with age of the bulls up to 6 to 7 yr. The concentration of circulating testosterone was unrelated to libido or semen quality.
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