The Food and Drug Administration's approval of Pfizer Animal Health's Excede for Swine has changed the pre-slaughter withdrawal period for the company's Excenel RTU and Naxcel products from zero to four days.

The approval doesn't change the pre-slaughter withdrawal period of 48 hours for the use of Excenel (ceftiofur hydrochloride) in cattle. And it doesn't affect the zero withdrawal period for the use of Naxcel (ceftiofur sodium) in other species.

Pfizer swine veterinarian Shelley Stanford says Excede for Swine has been assigned a 14-day withdrawal period because of its time-release formulation. Excenel and Naxcel have been reassigned a four-day withdrawal period.

By doing so, all three ceftiofur-based products for swine comply with the 0.25 ppm tolerance level established in the kidney, the target organ for monitoring tissue residues.

“The new kidney tolerance must be applied to all ceftiofur products because they all share the same metabolic pathway and the active metabolites from each cannot be differentiated,” adds Steve Sornsen, DVM, director, Veterinary Services for Pfizer.

The safety profile for Excenel and Naxcel remains unchanged, stresses Stanford.

Excede for Swine will be available to producers sometime in August.