title: Influence of ceftiofur sodium biobullet administration on tenderness and tissue damage in beef round muscle.
abstract: The effect of a biobullet (BB) containing freeze-dried ceftiofur sodium antibiotic on the presence of injection lesions, tissue damage, and histological properties, as well as Warner-Bratzler shear force (WBSF), of the biceps femoris was investigated. Steer calves (n = 25) were individually identified and assigned randomly to a product administration treatment date (7, 14, 21, 28, or 35 d before slaughter). At each pre-slaughter ceftiofur BB administration time, identified steers (n = 5) were humanely placed into a standard commercial restraining chute, where a BB implant was administered from a distance of 6.09 m. Following a standard finishing period (120 d), steers were transported to a commercial beef processing and humanely slaughtered. Following a 36-h postmortem chilling (1 degree C) period, carcasses were graded and fabricated according to industry-accepted procedures. Paired muscle samples were individually identified, collected, and aged for 14 d postmortem. Muscles were dissected into 1.27-cm strips, followed by observation and palpation for the presence of injection site lesions. Preslaughter administration times of 7 and 14 d resulted in the presence of injection lesions (80 and 20%, respectively). In addition to the control samples, no muscle damage was observed in cattle treated with BB implants 21, 28, or 35 d before slaughter. Warner-Bratzler shear force measurements taken near lesions of BB steaks and in areas 5.08 cm from lesions of control steaks tended to be higher (P < 0.10) than for other BB and control sample locations. Concentrations of insoluble and soluble collagen were higher (P < 0.05) at the site of the lesion center in lesion-afflicted vs. with control steaks. Histological determinations of the relative proportions of muscle, connective tissue, and fat were altered (P < 0.05) in BB lesion-afflicted steak cores; however, these differences were negated outside the core location of BB-treated and control steaks. It seems that using the ceftiofur BB implant system within 14 d of slaughter does create injection site lesions and increase WBSF; however, when the BB implant system, containing 100 mg of freeze-dried ceftiofur sodium, was used according to the recommended procedure (> or = 30 d preslaughter), tissue damage, alterations in histological and collagen properties, and increased meat toughness were not observed.
authors.affiliation: Department of Animal Science, Oklahoma State University, Stillwater 74078, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Morgan
authors.forename: A W
authors.initials: AW
authors.lastname: Tittor
authors.forename: W R
authors.initials: WR
authors.lastname: Lloyd
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002417:Cattle; D002511:Cephalosporins / Q000008:administration & dosage / Q000494:pharmacology*; D005524:Food Technology / Q000379:methods* / Q000592:standards; D007273:Injections, Intramuscular / Q000009:adverse effects / Q000662:veterinary*; D008297:Male; D008460:Meat / Q000592:standards*; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; C053503:ceftiofur