New research from The Ohio State University shows just how important a double plastic sheath can be during artificial insemination (A.I.).

The field trial included 2,220 lactating Holstein cows from three commercial herds. Cows were enrolled in a Presynch/Ovsynch or Presynch/Cosynch program. At the time of A.I., cows were randomly assigned to one of two groups:

  1. Treatment: A disposable sheath protector on top of the regular A.I. sheath. 
  2. Control: Cows were bred without the use of a protective sheath. 

Following breeding, researchers cultured swab samples from the A.I. catheter to determine level of bacterial contamination.

Researchers concluded that the use of a disposable sheath protector reduced contamination of the A.I. catheter, with only 51.9 percent contamination in the treatment group, compared to 98 percent in the control. It also improved pregnancies per A.I. in the treatment group to 30.1 percent versus 25.4 percent in the control group.

Although the study involved lactating cows, the cleanliness of A.I. procedures and equipment should not be compromised in heifers either. Please see the Gold Standards II for breeding guidelines.

The study results were presented in July at the 2011 American Dairy Science Association's annual meeting.

Sheath protectors improve fertility, reduce contamination