On-farm management decisions to improve beef quality of market dairy cows.
A 3-phase study was conducted to assess on-farm management decisions to reduce antibiotic residue violations and improve carcass characteristics in market (cull) dairy cows. In Phase 1, questionnaires were mailed to dairy producers (n = 142) to determine current on-farm management strategies for reducing antibiotic residues in market dairy cattle. In Phase 2, Holstein market cows (n = 77) were assigned randomly to each of the 3 feeding treatments (0, 30, or 60 d). Average daily gain (ADG), body condition score (BCS), and carcass characteristics were assessed. Phase 3 determined the meat withdrawal time of Holstein cows (n = 62) administered procaine penicillin G. Eighty-six percent of dairy farms responding to the questionnaire had at least one cow condemned annually, and no producer had a designated feeding protocol for market cows prior to selling. In Phase 2, ADG was greater in cows fed for 30 d (1.4+/-0.6 kg/d) than in cows fed for 60 d (0.9+/-0.4 kg/d). Additional feeding did not influence the carcass characteristics studied with the exception of kidney, pelvic and heart fat, which was higher in cows fed for 60 d compared with those fed for 0 and 30 d. In Phase 3, 31% of cows treated with procaine penicillin G exceeded the 10-d label withdrawal recommendation by an average of 3.1+/-1.9 d. Feeding market cows may not influence carcass characteristics, but can increase ADG and may ensure that recommended meat withdrawal times for antibiotics are exceeded.
Department of Animal and Range Sciences, New Mexico State University, Las Cruces, NM 88003, USA.
C A
CA
Rogers
A C
AC
Fitzgerald
M A
MA
Carr
B R
BR
Covey
J D
JD
Thomas
M L
ML
Looper
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D001823:Body Composition; D002417:Cattle; D003612:Dairying / Q000379:methods*; D004032:Diet; D004350:Drug Residues / Q000032:analysis*; D005260:Female; D008460:Meat / Q000032:analysis*; D010402:Penicillin G Procaine / Q000008:administration & dosage; D011786:Quality Control; D011795:Surveys and Questionnaires; D015430:Weight Gain
D000900:Anti-Bacterial Agents; D010402:Penicillin G Procaine