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Updated: Jul 30, 2026
05:36
A Tissue Culture Model of Estrogen-producing Primary Bovine Granulosa Cells
Published on: September 6, 2018
Effect of some steroid compounds on ovine rumen function
Science (New York, N.Y.)
|September 17, 1954
Summary
Stilbestrol, cholesterol, and estrone enhance the digestion of cellulose by rumen microorganisms. However, high levels of stilbestrol were not tolerated by sheep, indicating potential limitations for its use in animal feed.
Area of Science:
- Rumen microbiology
- Animal nutrition
- Endocrinology
Background:
- Cellulose digestion is crucial for ruminant nutrition.
- Rumen microorganisms play a key role in breaking down plant fiber.
- Hormonal compounds can influence microbial activity in the rumen.
Purpose of the Study:
- To investigate the effects of stilbestrol, cholesterol, and estrone on cellulose digestion by ovine rumen microorganisms.
- To evaluate the in vitro and in vivo efficacy of these compounds.
- To determine the tolerance levels of stilbestrol in sheep.
Main Methods:
- In vitro incubation of ovine rumen microorganisms with varying concentrations of stilbestrol, cholesterol, and estrone.
- In vivo studies using wethers to assess the effects of stilbestrol on cellulose digestion.
- Measurement of cellulose digestion rates.
Main Results:
- Stilbestrol (10 or 20 ppm) significantly increased cellulose digestion both in vitro and in vivo.
- Ovine wethers could not tolerate high levels of stilbestrol.
- Cholesterol and estrone also enhanced cellulose digestion by rumen microorganisms in vitro.
Conclusions:
- Stilbestrol, cholesterol, and estrone demonstrate potential as enhancers of cellulose digestion in ruminants.
- The high dosage of stilbestrol is not tolerated by sheep, suggesting a narrow therapeutic window.
- Further research is needed to optimize the use of these compounds for improved feed efficiency in livestock.
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