THE EFFECTS OF CEFTIOFUR SODIUM (NAXCEL) ON BOVINE OOCYTE AND PREIMPLANTATION EMBRYONIC-DEVELOPMENT ASSESSED BY IN-VITRO EMBRYO PRODUCTION TECHNIQUES

Ceftiofur sodium is a third-generation cephalosporin antibiotic with b road spectrum bactericidal activity against Gram-positive and Gram-neg ative bacteria including the beta-lactamase producing strains, In this study, we use in vitro techniques to examine the effects of low and h igh levels of ceftiofur sodium on the development of bovine oocytes/em bryos during oocyte maturation, oocyte fertilization and embryo cultur e, A total of 8590 oocytes was used in six independent experiments, ea ch in a randomized complete block design. Each replication within each experiment consisted of oocytes from the same abattoir collection of ovaries. There was no difference in embryo development when oocytes we re exposed to ceftiofur sodium during oocyte maturation or fertilizati on at low (10 and 50 mu g/mL) or high (100 and 200 mu g/mL) concentrat ions. However, when fertilized oocytes were exposed to concentrations greater than or equal to 50 mu g/mL during culture, ceftiofur sodium s ignificantly retarded embryo development: (e.g. the numbers of ova dev eloping to the morula and blastocyst stages were reduced, and a large proportion of embryos were blocked at the 8-cell stage). We conclude t hat ceftiofur sodium does not appear to have detrimental effects on oo cyte maturation and fertilization. However, long term exposure to high dosages of ceftiofur sodium during post-fertilization culture adverse ly affects embryo development in vitro.