The various compounds within the cephalosporin class of antibiotics have features similar to penicillin with ceftiofur, a third-generation cephalosporin approved to treat Bovine pneumonia and also Gram-negative infections in companion species. This drug is effective against susceptible Pseudomonas spp., Proteus spp., and Enterobacter spp. which are frequently encountered in hatcheries and are responsible for omphalitis in chicks.
It is common practice in the broiler industry to incorporate either gentamycin or ceftiofur in Marek’s disease diluents administered in ovo to enhance livability of chicks. In the egg industry, either of these antibiotics are added to Marek’s disease diluents and injected subcutaneously to replacement pullets at the hatchery. The use of gentamycin and ceftiofur has been questioned by the FDA, which conducted investigations in broiler hatcheries in 2008 to review the possibility that routine use might contribute to emerging drug resistance. Since ceftiofur is used extensively in human medicine, specifically to treat Gram-negative infections including meningitis, restricting use to approved applications is considered prudent by the FDA.
There is considerable doubt as to the justification for administering antibiotics as a routine to day old pullet chicks. Elevation in first week mortality following withdrawal of routine antibiotics generally denotes a defect in the chain of hygiene extending from egg collection from the parent flock through hatching. Administration of antibiotics is regarded as a “cover up” by many producers. Continued routine use of ceftiofur and gentamycin may have adverse implications for human health and consumer acceptance of the practice, especially with regard to the broiler industry.