First Defense Bolus & Gel

First Defense from Immucell is used as an aid in the prevention of neonatal beef and dairy calf scours caused by K99+ E. coli and Coronavirus. The only product available that protects against the 2 major causes of scours in calves. Maximum protection when administered to neo-natal calves within 12 hours of birth. Available in bolus or gel tube form.

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  • 100% bovine antibodies from colostrum
    • Vaccination concept perfected
  • Immediate protection
  • Consistent guaranteed antibody levels
  • USDA Proven results
  • 24 month shelf life
  • OMRI listed
    • OMRI listed for use on organic farms

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Calf scours (diarrhea) is one of the most common and costly diseases in calves, resulting from lack of sufficient protection from colostrum. The first 12 hours of a calf's life are critical for antibody absorption. ImmuCell continues to be on the forefront of scours prevention technology, manufacturing and selling First Defense®, the most popular and convenient scours preventive administered to calves.


Prepared from hyperimmune bovine colostrum, First Defense® is a bolus which dissolves readily upon reaching the calf's stomach, providing protective levels of antibodies to potential sites of intestinal infection. These highly specific antibodies serve to block enterotoxigenic E. coli adherence and interfere with coronavirus infection of intestinal epithelial cells, thereby reducing scours related morbidity and mortality. First Defense® delivers preformed immunity and immediate protection when calves need it most. Maximal protection is achieved when administered in the first 12 hours after birth and used in conjunction with good colostrum feeding and calf nutrition programs.


Quick and easy to administer. Do not vaccinate calves with oral coronavirus products within 5 days of administration of First Defense.

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