Bovine Estrus Detection

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Bovine Estrus Detection

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Bovine Estrus ("Heat") Detection Summary

by Karen L. Jacobsen, BS, DVM, MS,

Farm Animal Resources & Management (F.A.R.M.), LLC

1120 Cherokee Circle, Athens, GA 30606

706-340-0999 (mobile)

Heat detection has a larger impact on the success of bovine artificial insemination (A.I.) programs than any other management factor. The dairy or beef producer must become proficient at heat detection to be successful as an A.I. breeder.

The only reliable sign of bovine estrus is the cow standing to allow other cows to mount her.  The cow may stand only 4-6 seconds each time.  There will be an average of 1.5 mounts per hour.

The only primary sign of estrus in the cow:

  • Cow standing to be mounted

The secondary signs of estrus in the cow include:

  • Clear mucous discharge
  • Swollen, red vulva
  • Frequent urination
  • Restless behavior, Vocalization ("bawling")
  • Sniffing behavior
  • Chin resting and rubbing
  • Ruffled hair on tailhead and/or flanks
  • Decreased milk production/off feed
  • Mounting other cows (unreliable sign)