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Virginia Cooperative Extension -
 Knowledge for the CommonWealth

Beef Management Tips

Livestock Update, June 2002

John Hall, Extension Animal Scientist, Beef, VA Tech

June Beef Management Calendar

Spring Calving Herds

Fall Calving Herds

Eazi-Breed® CIDR® finally approved for use in US
In early May, the FDA approved a new tool for estrous synchronization in US cattle. Producers in other countries have been able to use Controlled Intervaginal Drug Release devices (CIDRs) for several years. The CIDR supplies progesterone to keep cows and heifers out of heat during the synchronization process. Research indicates that when CIDRs are used in combination with analogs for prostaglandin F2a (Lutalyse, Prostamate, Estrumate) they are very effective in synchronizing estrus in cows and heifers. Combinations with GnRH or estradiol ciponate (ECP) should allow for effective timed insemination. Look for a publication early this fall on using CIDRs.

Stocker cattle benefit from reimplanting and ionophores
Stocker cattle will gain an extra 20 to 25 lbs if reimplanted in mid summer. Producers should use the same implant as previously given or another implant for that weight and sex of cattle. Ionophores can also benefit grazing stockers. Products like GainPro® or Rumensin® are approved for grazing cattle and can result in increased gain of 10 to 15%. Remember that response to implants and especially ionophores require abundant good quality pasture. Results with these products after July may be disappointing if you are grazing over-mature grasses or have limited grazing available.

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