# Why does a cow magnet work?

**URL:** <https://boards.straightdope.com/t/why-does-a-cow-magnet-work/454679>\
**Category:** Factual Questions\
**Created:** [June 29, 2008, 6:58pm UTC](https://boards.straightdope.com/t/why-does-a-cow-magnet-work/454679 "2008-06-29T18:58:07Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\
**Post date:** [June 29, 2008, 6:58pm UTC](https://boards.straightdope.com/t/why-does-a-cow-magnet-work/454679/1 "2008-06-29T18:58:07Z")

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Farmers drop a cow magnet down the cattle’s throat. It’s supposed to collect metal the cows eat so they don’t die from metal in the stomachs. Why would metal collected to the magnet be any less harmful than metal not collected by the magnet still in the digestive tract?

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [June 29, 2008, 7:07pm UTC](https://boards.straightdope.com/t/why-does-a-cow-magnet-work/454679/2 "2008-06-29T19:07:16Z")

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Not exactly. The magnet remains the cow’s rumen, collecting any ferrometallic material the cow my ingest incidentally. Since it remains in the rumen–which is tougher by nature than the rest of the digestive system, as it’s used to process the tough plant material the cow eats–it can’t cause damage to the more delicate lower digestive tract. See Wiki on [Cow Magnets](http://en.wikipedia.org/wiki/Cow_magnet).

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**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\
**Post date:** [June 29, 2008, 9:17pm UTC](https://boards.straightdope.com/t/why-does-a-cow-magnet-work/454679/3 "2008-06-29T21:17:08Z")

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Thanks